Complete genome sequence provides insights into the quorum sensing-related spoilage potential of Shewanella baltica 128 isolated from spoiled shrimp.

Shewanella baltica 128 is a specific spoilage organism (SSO) isolated from the refrigerated shrimp that results in shrimp spoilage. This study reported the complete genome sequencing of this strain, with the primary annotations associated with amino acid transport and metabolism (8.66%), indicating that S. baltica 128 has good potential for degrading proteins. In vitro experiments revealed Shewanella baltica 128 could adapt to the stress conditions by regulating its growth and biofilm formation. Genes that related to the spoilage-related metabolic pathways, including trimethylamine metabolism (torT), sulfur metabolism (cysM), putrescine metabolism (speC), biofilm formation (rpoS) and serine protease production (degS), were identified. Genes (LuxS, pfs, LuxR and qseC) that related to the specific QS system were also identified. Complete genome sequence of S. baltica 128 provide insights into the QS-related spoilage potential, which might provide novel information for the development of new approaches for spoilage detection and prevention based on QS target.

Restless legs syndrome in end stage renal disease patients undergoing hemodialysis.

BACKGROUND: The prevalence of Restless legs syndrome (RLS) in End Stage Renal Disease (ESRD) patients is higher than that in the general population. However, the associations of RLS within the ESRD population are inconsistent and RLS is usually neglected in dialysis centers, although it impairs the life quality among ESRD patients. We aim to investigate the prevalence of RLS in patients with ESRD undergoing maintenance hemodialysis and evaluate the risk factors of developing RLS and the effect of RLS on quality of life among ESRD patients. METHODS: ESRD patients undergoing maintenance hemodialysis in Shanghai General Hospital dialysis unit from July 2016 to October 2016 were enrolled in the study. RLS was diagnosed according to the criteria of the International Restless Legs Syndrome Study Group (IRLSSG). IRLSSG Severity Scale was used to evaluate the severity of RLS. Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality, and Hospital Anxiety and Depression Scale (HADS) was used to estimate anxiety and depression. Serologic and historic variables were analyzed to determine predictors of RLS in the ESRD population. RESULTS: A total of 137 ESRD patients were enrolled. The prevalence of RLS among the ESRD patients was 20.44%. The risk of RLS was increased significantly in females (OR = 2.729, p = 0.032) and daily alcohol drinkers (OR = 4.716, p = 0.022). RLS increased the risks of sleep disorders (25/28, 89.3% vs 73/109, 67.0%, p = 0.02) and sedative hypnotics intake (7/28, 25.0% vs 10/109, 9.2%, p = 0.047) and impaired the sleep quality (7/109 vs 11/28, p = 0.001) according to PSQI sum scores. CONCLUSION: A high RLS prevalence among the ESRD patients undergoing hemodialysis was confirmed. ESRD patients who are women and drinking alcohol have a higher risk of RLS. The sleep quality was significantly impaired and sleeping medication use was more common among the ESRD patients with RLS.

Quantitative Proteomic Analysis Uncovers the Mediation of Endoplasmic Reticulum Stress-Induced Autophagy in DHAV-1-Infected DEF Cells.

Autophagy is a tightly regulated catabolic process and is activated in cells in response to stress signals. Despite extensive study, the interplay between duck hepatitis A virus type 1 (DHAV-1) and the autophagy of host cells is not clear. In this study, we applied proteomics analysis to investigate the interaction mechanism between DHAV-1 and duck embryo fibroblast (DEF) cells. In total, 507 differentially expressed proteins (DEPs) were identified, with 171 upregulated proteins and 336 downregulated proteins. The protein expression level of heat shock proteins (Hsps) and their response to stimulus proteins and zinc finger proteins (ZFPs) were significantly increased while the same aspects of ribosome proteins declined. Bioinformatics analysis indicated that DEPs were mainly involved in the "response to stimulus", the "defense response to virus", and the "phagosome pathway". Furthermore, Western blot results showed that the conversion of microtubule-associated protein 1 light chain 3-I (LC3-I) to the lipidation form of LC3-II increased, and the conversion rate decreased when DEF cells were processed with 4-phenylbutyrate (4-PBA). These findings indicated that DHAV-1 infection could cause endoplasmic reticulum (ER) stress-induced autophagy in DEF cells, and that ER stress was an important regulatory factor in the activation of autophagy. Our data provide a new clue regarding the host cell response to DHAV-1 and identify proteins involved in the DHAV-1 infection process or the ER stress-induced autophagy process.

AHLs-produced bacteria in refrigerated shrimp enhanced the growth and spoilage ability of Shewanella baltica.

Shewanella baltica is the predominant bacteria in spoiled shrimp (Litopenaeus vannamei), however, the spoilage ability and the mechanism of S. baltica is still unknown. S. baltica can't produce the signal molecule of acyl-homoserine-lactones (AHLs), so the aim of this study was to investigate how wild type S. baltica SA03 (WT SA03) eavesdrop exogenous AHLs to enhance its spoilage ability through LuxR receptor. The results indicated that Aeromonas spp. (Aer), Acinetobacter spp. (Aci) and Serratia spp. (Ser) isolated from refrigerated shrimp can produce different AHLs. WT SA03 can eavesdrop the AHLs of Aer (C4-HSL), Aci (O-C6-HSL) and Ser (C6-HSL, O-C6-HSL) to enhance its growth, especially Ser. Exogenous C4-HSL and C6-HSL enhanced biofilm formation of WT SA03, and C6-HSL and O-C6-HSL enhanced thioredoxin reductase trxB mRNA expression. However, the luxR mutant of WT SA03 (ΔluxR SA03) lost or weakened the role of using environmental AHLs. In vivo experiments, the lag time of WT SA03 was shortened by 6.4 h, 6.2 h and 14.4 h by co-inoculated with Aer, Aci and Ser, respectively. The total volatile basic nitrogen (TVB-N) were significantly enhanced in the samples co-inoculated with WT SA03 and Aer (or Aci, Ser) than those of ΔluxR SA03 and Aer (or Aci, Ser) (p < 0.05). The results showed that S. baltica SA03 can utilize AHLs produced by other bacteria to enhance its growth and spoilage ability through LuxR receptor system. Quorum sensing based on AHLs of bacteria might as the potential targets for food spoilage control.

Phosphate stimulates myotube atrophy through autophagy activation: evidence of hyperphosphatemia contributing to skeletal muscle wasting in chronic kidney disease.

BACKGROUND: Accelerated muscle atrophy is associated with a three-fold increase in mortality in chronic kidney disease (CKD) patients. It is suggested that hyperphosphatemia might contribute to muscle wasting, but the underlying mechanisms remain unclear. Although evidence indicates that autophagy is involved in the maintenance of muscle homeostasis, it is not known if high phosphate levels can result in activation of autophagy, leading to muscle protein loss. METHODS: Immortalized rat L6 myotubes were exposed to a high concentration of phosphate, with or without autophagy inhibition. Myotube atrophy was examined by phase contrast microscopy. Autophagic activity was assessed by measuring the expression of microtubule-associated protein 1 light chain 3 (LC3) and p62 using quantitative real-time polymerase chain reaction and western blot. RESULTS: Phosphate induced cell atrophy in L6 myotubes in a dose- and time-dependent manner, and these responses were not associated with calcification or osteogenesis. Phosphate also dose- and time-dependently increased the LC3-II/LC3-I ratio. Inhibition of autophagy with wortmannin or knockdown of Atg5 significantly suppressed myotube atrophy caused by high phosphate concentration. CONCLUSIONS: High phosphate concentration induces muscle cell atrophy through the activation of autophagy. Targeting autophagy could be a therapeutic strategy for preventing muscle wasting caused by hyperphosphatemia.

Acyl-homoserine-lactones receptor LuxR of Shewanella baltica involved in the development of microbiota and spoilage of refrigerated shrimp.

Numerous bacterial species utilize quorum sensing molecules acyl-homoserine-lactones (AHLs) to communicate, however, crosstalk often complicates the dynamics and behaviors of mixed populations. In this study, we developed a luxR mutant of wild type Shewanella baltica SA03 (WT SA03), and aimed to investigate the role of S. baltica LuxR (AHLs receptor) involved in the spoilage of refrigerated shrimp (Litopenaeus vannamei) by inoculating WT SA03 and luxR mutant of S. baltica SA03 (ΔluxR SA03), respectively. The results indicated the maximum growth rate of total viable bacteria in shrimp inoculated with ΔluxR SA03 was 73.34% lower than that of WT SA03. The lag time of total bacteria in shrimp treated with ΔluxR SA03 were 87.6 h, significantly longer than that of WT SA03. Meanwhile, the total volatile basic nitrogen concentrations of shrimp treated with WT SA03 were significantly higher than that of ΔluxR SA03 after 2 days of storage, which were in agreement with the decrease of the content of AHLs of the shrimp. The results indicated S. baltica might utilize AHLs produced by other bacteria and accelerate the shrimp spoilage process through LuxR receptor system.

Potassium metabolism in continuous ambulatory peritoneal dialysis patients.

BACKGROUND: Hypokalemia is common and may have contributed to the poor clinical outcome in peritoneal dialysis (PD) patients. In this study, we made a detailed investigation on the potassium metabolism in continuous ambulatory peritoneal dialysis (CAPD) patients and tried to find out the possible factors associated with the high prevalence of hypokalemia in PD patients. METHODS: A cross-sectional survey in 243 clinically stable CAPD patients was made in our PD center in 2010. Patients were divided into four groups according to whether they were anuric or not and different dialysis regimens. Patients' demographic data and data on potassium metabolism including dietary potassium intakes, residual renal potassium, and peritoneal dialysis potassium removal were collected. RESULTS: The average potassium intake in our 243 PD patients was 32.1 ± 11.1 mmol/day. The total potassium removal was significantly higher in non-anuric patients as compared to anuric patients (33.2 ± 9.1 vs. 23.0 ± 4.7 mmol/day for 3 exchanges per day and 35.2 ± 8.9 vs. 28.6 ± 6.3 mmol/day for 4 exchanges per day, respectively, p < 0.01) and in anuric patients dialyzed with 4 exchanges per day as compared to anuric patients dialyzed with 3 exchanges per day (28.6 ± 6.3 vs. 23.0 ± 4.7 mmol/L, p < 0.05). Compared to non-anuric patients dialyzed with 3 exchanges per day, serum potassium level was significantly lower (4.1 ± 0.7 vs. 4.5 ± 0.7 mmol/L, p < 0.05) while the prevalence of hypokalemia was significantly higher (22.2% vs. 9.3%, p < 0.05) in non-anuric patients that dialyzed with 4 exchanges per day. There was a strong correlation between renal potassium removal and renal urea Kt/V (R(2) linear = 0.645, p < 0.05). In a linear multiregression analysis, dietary potassium intake, intracellular water (ICW) significantly positively predicted serum potassium level while dialysis exchanges, residual renal function (RRF), D/P potassium all significantly negatively predicted serum potassium levels. CONCLUSIONS: Our study suggested that if potassium intake was limited in PD patients, we should be aware of the risk of hypokalemia with high doses of PD when patients have good RRF. Our study also suggested that potassium removal in PD patients may not necessarily reflect potassium intake even if serum potassium is normal, the effect of ICW should be considered when evaluating potassium homeostasis.

Nonstructural protein 2A2 from Duck hepatitis A virus type 1 inhibits interferon beta production by interaction with mitochondrial antiviral signaling protein and TANK-binding kinase 1.

Type I interferon (IFN-I) is essential for the regulation of host-virus interactions, and viruses have evolved strategies to escape the host immune response. Duck hepatitis A virus type 1 (DHAV-1) causes severe liver necrosis and hemorrhage, neurological symptoms, and high mortality in ducklings. However, how DHAV-1 interacts with the duck innate immune system remains unclear. In this study, DHAV-1-encoded proteins were cloned, and DHAV-1 2A2 was shown to strongly suppress IFN-ß-luciferase activity, triggered by Sendai virus and polyriboinosinic polyribocytidylic acid [poly(I:C)], along with the transcription of IFN-ß and downstream antiviral genes, including OASL, PKR, and TNF-a. In addition, 2A2 interacts with the central adaptor proteins mitochondrial antiviral signaling (MAVS) and TANK-binding kinase 1 (TBK1) by its N-terminal 1-100 amino acids (aa), thus leading to the inhibition of IFN-ß production. Importantly, the deletion of the N-terminal 1-100 aa region of 2A2 abolished inhibition of IFN-I production. Moreover, the transmembrane domain of the MAVS protein and the ubiquitin domain of TBK1 were demonstrated to be required for interaction with DHAV-1 2A2. These findings revealed a novel strategy by which DHAV-1 hijacks cellular immunosurveillance and provided new insights into controlling the disease.

[Effect of Cordyceps sinensis on the expression of HIF-1α and NGAL in rats with renal ischemia-reperfusion injury].

OBJECTIVE: To observe the level of urinary neutrophil gelatinase-associated lipocalin (NGAL), the expression of hypoxia inducible factor-1α (HIF-1α) and NGAL in rat kidney after renal ischemia and reperfusion (I/R), before and after the treatment with Cordyceps Sinensis (C. sinensis), and to explore the mechanism of C. sinensis against I/R injury. METHODS: A total of 45 healthy male Sprague-Dawley rats were randomly divided into a sham group, a renal I/R model group, and a C. sinensis group (15 in each group).The rats in the sham group and the renal I/R model group were intragastrically administered saline (2 mL/d), and rats in the treatment group were intragastricabby administered of C. sinensis [5.0 g/(kg.d)]. The rats were sacrificed at 24, 48, and 72 h, respectively after the reperfusion and urinary N-acetyl-ß-D-glucosaminidase (NAG) level was measured, renal function in rats was detected, and the pathological changes were observed with HE staining. We determined the urinary NGAL levels in the rats by ELISA, the expression of HIF-1α mRNA by RT-PCR, and the expressions of HIF-1α and NGAL proteins by confocal immunofluorescence. RESULTS: Compared with the sham group, the levels of BUN, SCr, levels of NAG and NGAL in urine were increased in the I/R group and the C. sinensis group, reached a peak at 24 h after the reperfusion and slowly declined at 48 and 72 h. Glomerular and tubulointerstitial areas in the sham group did not show any pathological change. Induced pathological changes included tubular cell necrosis, focal areas of proximal tubular dilation, distal tubular casts, effacement and loss of proximal tubule brush border, etc. Compared with the sham group, the expression of HIF-1α and NGAL in the kidney tissues of the I/R group and the C. sinensis group increased. C. sinensis can lower the level of NAG and NGAL in the urine and the expression of NGAL protein in the kidney tissues. It up-regulated the expression of HIF-1α mRNA and protein in the kidney tissues whilst attenuated the pathological changes. CONCLUSION: Renal I/R injury in rats can lead to pathological changes in renal tubular epithelial cells and renal interstitial damage, which are consistent with the pathological features of acute kidney injury (AKI).The level of urinary NAGL increases after the I/R, and positively correlates with the level of urinary NAG and pathological changes, suggesting that urinary NGAL may serve as a urinary biomarker for specific detection of tubular injury in AKI. C. sinensis can attenuate the renal I/ R-induced AKI. Its mechanism may be associated with up-regulating the expression of HIF-1α and down-regulating the expression of NGAL in the kidney tissues.

Long Noncoding RNA Expression Rofiles Elucidate the Potential Roles of lncRNA- XR_003496198 in Duck Hepatitis A Virus Type 1 Infection.

Duck hepatitis A virus type 1 (DHAV-1) is a highly lethal virus that severely affects the duck industry worldwide. Long noncoding RNAs (lncRNAs) exert crucial roles in pathogen attacks. Here, we conducted deep transcriptome analysis to investigate the dynamic changes of host lncRNAs profiles in DHAV-1-infected duck embryo fibroblasts. We identified 16,589 lncRNAs in total and characterized their genomic features. Moreover, 772 and 616 differentially expressed lncRNAs (DELs) were screened at 12 and 24 h post-infection. Additionally, we predicted the DELs' cis- and trans-target genes and constructed lncRNA-target genes regulatory networks. Functional annotation analyses indicated that the putative target genes of DELs participated in diverse vital biological processed, including immune responses, cellular metabolism, and autophagy. For example, we confirmed the dysregulation of pattern recognition receptors (TLR3, RIG-I, MDA5, LGP2, cGAS), signal transducers (STAT1), transcription factors (IRF7), immune response mediators (IL6, IL10, TRIM25, TRIM35, TRIM60, IFITM1, IFITM3, IFITM5), and autophagy-related genes (ULK1, ULK2, EIF4EBP2) using RT-qPCR. Finally, we confirmed that one DHAV-1 induced lncRNA-XR_003496198 is likely to inhibit DHAV-1 replication in DEFs. Our study comprehensively analyzed the lncRNA profiles upon DHAV-1 infection and screened the target genes involved in the innate immune response and autophagy signaling pathway, thereby revealing the essential roles of duck lncRNAs and broadening our understanding of host-virus interactions.

Notch2/Hes-1 pathway plays an important role in renal ischemia and reperfusion injury-associated inflammation and apoptosis and the γ-secretase inhibitor DAPT has a nephroprotective effect.

UNLABELLED: This study aims to investigate the role of Notch pathway in the renal ischemia/reperfusion injury (IRI)-associated inflammation and apoptosis. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into three groups: normal saline (NS)-treated sham rats, NS-treated ischemia/reperfusion (I/R) rats, and N-[N-(3,5-difluorophenacetyl-l-alanyl)]-S-phenylglycine t-butyl ester (DAPT) (a γ-secretase inhibitor) treated I/R rats. I/R rat model underwent nephrectomy of the right kidney and was subjected to 60 min of left renal pedicle occlusion followed by 24 h, 48 h, and 72 h of reperfusion, respectively. The levels of creatinine, urea nitrogen (BUN), interleukin (IL)-6, tumor necrosis factor (TNF)-α in serum samples and urinary N-acety-ß-d-glucosaminidase (NAG) were assayed. Histological examinations were performed. The protein expression of Notch2, hairy/enhancer of split 1 (hes-1), NF-κB2, monocyte chemoattractant protein (MCP)-1, B-cell lymphoma 2 (bcl-2), and bcl-2-associated X (bax) were detected and the degree of apoptosis of tubular cells was evaluated. RESULTS: Renal IR induced severe tubular damage, caused significant increases in the Scr, BUN, IL-6, TNF-α, urinary NAG, Notch2, hes-1, NF-κB2, MCP-1, ratio of tubule cells apoptosis, and reduction in the ratio of bcl-2 to bax. However, DAPT treatment significantly reduced the level of Scr, BUN, IL-6, TNF-α, and NAG. Thus, I/R activates Notch2/hes-1 signaling and DAPT treatment can ameliorate the severity of tubular damage after renal IRI, lower the expression of NF-κB2, MCP-1, and bax protein, increase the expression of bcl-2 protein, and reduce the ratio of terminal 2-deoxyuridine 5-triphosphate nick end-labeling-positive cells. CONCLUSION: Notch signaling plays an important role in the renal IRI-associated inflammation and apoptosis. DAPT can protect against IRI through partly suppressing inflammation and apoptosis, which could constitute a new target for AKI.

Integrated miRNA and mRNA Expression Profiles Reveal Differentially Expressed miR-222a as an Antiviral Factor Against Duck Hepatitis A Virus Type 1 Infection.

Duck hepatitis A virus 1 (DHAV-1) is a highly contagious etiological agent that causes acute hepatitis in young ducklings. MicroRNAs (miRNAs) play important regulatory roles in response to pathogens. However, the interplay between DHAV-1 infection and miRNAs remains ambiguous. We characterized and compared miRNA and mRNA expression profiles in duck embryo fibroblasts cells (DEFs) infected with DHAV-1. In total, 36 and 96 differentially expressed (DE) miRNAs, and 4110 and 2595 DE mRNAs, were identified at 12 and 24 h after infection. In particular, 126 and 275 miRNA-mRNA pairs with a negative correlation were chosen to construct an interaction network. Subsequently, we identified the functional annotation of DE mRNAs and target genes of DE miRNAs enriched in diverse Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, which may be important for virus resistance, cell proliferation, and metabolism. Moreover, upregulated miR-222a could negatively regulate DHAV-1 replication in DEFs and downregulate integrin subunit beta 3 (ITGB3) expression by targeting the 3' untranslated region (3'UTR), indicating that miR-222a may modulate DHAV-1 replication via interaction with ITGB3. In conclusion, the results reveal changes of mRNAs and miRNAs during DHAV-1 infection and suggest miR-222a as an antiviral factor against DHAV-1.

High Mobility Group Box 1 Promotes Aortic Calcification in Chronic Kidney Disease via the Wnt/ß-Catenin Pathway.

Vascular calcification (VC) is common in chronic kidney disease (CKD), where cardiovascular mortality remains the leading cause of death. Here, we examined the role of high-mobility group box1 (HMGB1), a nuclear DNA-binding protein involved in inflammation, in aortic calcification and renal dysfunction induced by high phosphate in a mouse model of CKD induced by 5/6 nephrectomy. HMGB1 and kidney function markers were measured by ELISA in the serum of CKD patients and in CKD mice. Sections of the aortas of mice were analyzed by immunofluorescence and Alizarin red staining, and protein lysates were generated to analyze the expression of related proteins in response to silencing of HMGB1 or ß-catenin by western blotting. Our results showed that serum HMGB1 levels were significantly higher in CKD patients than in healthy controls and related to disease stage. High phosphate promoted the translocation of HMGB1 from the nucleus to the cytosol and aortic calcification in CKD mice in vivo, whereas HMGB1 knockdown ameliorated part of renal and vascular function. ß-catenin silencing reversed high phosphate-induced calcification and restored renal marker levels. Taken together, our results suggest that HMGB1 is involved in VC associated with CKD via a mechanism involving the ß-catenin.

[Measurement of dissolved organic nitrogen with nanofiltration pretreatment and its distribution characteristics in landscape water].

In this study, we present a nanofiltration (NF90, NF270) pretreatment to increase the precision of dissolved organic nitrogen (DON) measurements in water samples. The variations of DON measurements with and without NF pretreatment were investigated. And the effects on the removal of dissolved inorganic nitrogen (DIN) by NF90 and NF270 were compared. As shown in the results, the average removal rates reached 30.7%, 55.9% of NH4(+)-N, 50.0%, 73.1% of NO3(-) -N and 42.9%, 72.0% of NO2(-)-N for NF90 and NF270 pretreatment, respectively. NF270 was obviously more effective to remove the DIN species. Concentrations of DON measured using traditional methods varied from 0.09 to 0.46 mg x L(-1), with negative concentration (-0.08 mg x L(-1)) at site 2 and the DIN/TDN ratio ranged from 85.3% to 105%; while the concentrations of DON measurements varied from 0.03 to 0.58 mg x L(-1), and the DIN/TDN ratio ranged from 76.1% to 90.6% for NF90 pretreatment and varied from 0.10 to 0.59 mg x L(-1), and the DIN/TDN ratio ranged from 47.5% to 84.5% for NF270 pretreatment. The results indicated that nanofiltration pretreatment could effectively remove the DIN species, decrease the standard deviation of DON measurements and increase the precision of DON measurements. The distribution of DON in water samples of Beijing Olympic Forest Park was investigated. The results showed that there was seasonal variation in the concentrations of DON in landscape water from the Olympic Forest Park. And there was significant difference between the north and south part. The DON concentrations were less than 0.2 mg x L(-1) in November, March and May and higher in July in the north part, while the DON concentrations were lower in May and higher in November and March in the south part, ranging from 0.40-0.65 mg x L(-1).

Fibroblast growth factor-23 and interleukin-6 are risk factors for left ventricular hypertrophy in peritoneal dialysis patients.

BACKGROUND: Left ventricular hypertrophy (LVH) is a major risk factor for cardiovascular death in dialysis patients. Fibroblast growth factor-23 (FGF-23) and interleukin-6 (IL-6) were thought to be related to cardiovascular diseases (CVDs) in dialysis. METHODS: To determine the relationship between FGF-23, IL-6 and LVH in continuous ambulatory peritoneal dialysis (CAPD) patients, serum FGF-23 and IL-6 levels as well as standard laboratory parameters were assessed in 62 CAPD patients and 30 healthy controls. LVH was determined by echocardiography in dialysis patients. RESULTS: Serum FGF-23 and IL-6 levels were significantly higher in CAPD patients than in healthy controls, whereas both were higher in patients with LVH than in patients without LVH. FGF-23 was found to be positively associated with left ventricle mass index (LVMI) and serum phosphate. IL-6 level was positively associated with LVMI and negatively correlated with serum albumin and hemoglobin. Serum FGF-23 level was positively correlated with IL-6 level. CONCLUSION: FGF-23 and IL-6 are independent risk factors for LVH in CAPD patients and both collaborated in causing LVH in CAPD.

Lack of an association between a newly identified promoter polymorphism (-1702G > A) of the leukotriene C4 synthase gene and aspirin-intolerant asthma in a Korean population.

Aspirin-intolerant asthma (AIA) is a distinct clinical syndrome that refers to the development of bronchoconstriction in asthmatic individuals following the ingestion of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs). It is widely recognized that increased cysteinyl leukotriene (cysLT) biosynthesis is associated with the development and progression of AIA. Leukotriene C4 synthase (LTC4S) is the terminal enzyme in cysLT production and is a strong candidate gene in the pathogenesis of aspirin-intolerant asthma (AIA). In this paper, we report a new single nucleotide polymorphism (SNP) of the LTC4S promoter, -1702G>A, in AIA patients and evaluate its genetic role in the association with the LTC4S-444 A>C polymorphism. We enrolled 110 AIA patients, 125 aspirin-tolerant asthma (ATA) patients, and 125 normal controls. SNP genotyping of the LTC4S-1702G>A and -444A>C polymorphisms was performed using SNP-IT assays. Haplotype analyses were performed using Haploview version 2.05, which is based on an estimation-maximization (EM) algorithm. There were no significant differences in the allele or genotype frequencies of the LTC4S-1702G>A and -444A>C polymorphisms among the three groups (p > 0.05), with no significant differences in the observed haplotype frequencies (p > 0.05). Moreover, no significant associations were found between the genotype of each SNP in AIA patients with the clinical characteristics, including a forced expiratory volume in one second (FEV1) %, a provocation concentration of methacholine to induce more than 20% decrease of FEV1 (PC20) to methacholine, and serum total IgE levels (p > 0.05). These results indicate that there is no association between these two promoter polymorphisms of LTC4S and the phenotype of AIA in a Korean population.