Expression of the core promoter factors TATA box binding protein and TATA box binding protein-related factor 2 in Drosophila germ cells and their distinct functions in germline development.

In Drosophila, the expression of germline genes is initiated in primordial germ cells (PGCs) and is known to be associated with germline establishment. However, the transcriptional regulation of germline genes remains elusive. Previously, we found that the BTB/POZ-Zn-finger protein, Mamo, is necessary for the expression of the germline gene, vasa, in PGCs. Moreover, truncated Mamo lacking the BTB/POZ domain (MamoAF) is a potent vasa activator. In this study, we investigated the genetic interaction between MamoAF and specific transcriptional regulators to gain insight into the transcriptional regulation of germline development. We identified a general transcription factor, TATA box binding protein (TBP)-associated factor 3 (TAF3/BIP2), and a member of the TBP-like proteins, TBP-related factor 2 (TRF2), as new genetic modifiers of MamoAF. In contrast to TRF2, TBP was found to show no genetic interaction with MamoAF, suggesting that Trf2 has a selective function. Therefore, we focused on Trf2 expression and investigated its function in germ cells. We found that Trf2 mRNA, rather than Tbp mRNA, was preferentially expressed in PGCs during embryogenesis. Depletion of TRF2 in PGCs resulted in decreased mRNA expression of vasa. RNA interference-mediated knockdown showed that, while Trf2 is required for maintenance of germ cells, Tbp is needed for their differentiation during oogenesis. Therefore, these results suggest that Trf2 and Tbp expression is differentially regulated in germ cells and that these factors have distinct functions in Drosophila germline development.

A truncated form of a transcription factor Mamo activates vasa in Drosophila embryos.

Expression of the vasa gene is associated with germline establishment. Therefore, identification of vasa activator(s) should provide insights into germline development. However, the genes sufficient for vasa activation remain unknown. Previously, we showed that the BTB/POZ-Zn-finger protein Mamo is necessary for vasa expression in Drosophila. Here, we show that the truncated Mamo lacking the BTB/POZ domain (MamoAF) is a potent vasa activator. Overexpression of MamoAF was sufficient to induce vasa expression in both primordial germ cells and brain. Indeed, Mamo mRNA encoding a truncated Mamo isoform, which is similar to MamoAF, was predominantly expressed in primordial germ cells. The results of our genetic and biochemical studies showed that MamoAF, together with CBP, epigenetically activates vasa expression. Furthermore, MamoAF and the germline transcriptional activator OvoB exhibited synergy in activating vasa transcription. We propose that a Mamo-mediated network of epigenetic and transcriptional regulators activates vasa expression.

H3K36 Trimethylation-Mediated Epigenetic Regulation is Activated by Bam and Promotes Germ Cell Differentiation During Early Oogenesis in Drosophila.

Epigenetic silencing is critical for maintaining germline stem cells in Drosophila ovaries. However, it remains unclear how the differentiation factor, Bag-of-marbles (Bam), counteracts transcriptional silencing. We found that the trimethylation of lysine 36 on histone H3 (H3K36me3), a modification that is associated with gene activation, is enhanced in Bam-expressing cells. H3K36me3 levels were reduced in flies deficient in Bam. Inactivation of the Set2 methyltransferase, which confers the H3K36me3 modification, in germline cells markedly reduced H3K36me3 and impaired differentiation. Genetic analyses revealed that Set2 acts downstream of Bam. Furthermore, orb expression, which is required for germ cell differentiation, was activated by Set2, probably through direct H3K36me3 modification of the orb locus. Our data indicate that H3K36me3-mediated epigenetic regulation is activated by bam, and that this modification facilitates germ cell differentiation, probably through transcriptional activation. This work provides a novel link between Bam and epigenetic transcriptional control.

Active vitamin D analogs, maxacalcitol and alfacalcidol, as maintenance therapy for mild secondary hyperparathyroidism in hemodialysis patients - a randomized study.

BACKGROUND: The present randomized study was designed to compare the efficacy between two active vitamin D analogs, alfacalcidol (ACD) and maxacalcitol (OCT), for the management of mild secondary hyperparathyroidism (SHPT) in dialysis patients. METHODS: SHPT in all 32 patients analyzed in the study was initially treated with OCT. Once patients' intact PTH levels decreased to the target range of 150 - 180 pg/mL, they were randomized either to switch to ACD at 0.5 µg/day (n = 14), or to remain on an effectively unchanged dose of OCT (n = 13). Phosphate, calcium, and intact PTH levels were measured every 2 weeks for 12 weeks and vitamin D doses were changed according to target ranges of phosphate (3.5 - 6.0 mg/dL), calcium (albuminadjusted calcium: 8.4 - 10.0 mg/dL), and intact parathyroid hormone (60 - 180 pg/mL). Achievement rates of the target ranges of the parameters were estimated. RESULTS: Baseline calcium levels in the OCT group were significantly higher than in the ACD group. Changes in achievement rates of target ranges of intact PTH and calcium during the study did not differ significantly between the vitamin D drugs. Changes in calcium levels in the OCT and ACD groups were similar during the study. Achievement rates of the target range of phosphate in both groups were also similar until 8 weeks, although the rate in the OCT group declined at 10 weeks. CONCLUSIONS: The efficacy and safety of OCT for the treatment of mild SHPT are similar to those of ACD in hemodialysis patients.

Genetically encoded system to track histone modification in vivo.

Post-translational histone modifications play key roles in gene regulation, development, and differentiation, but their dynamics in living organisms remain almost completely unknown. To address this problem, we developed a genetically encoded system for tracking histone modifications by generating fluorescent modification-specific intracellular antibodies (mintbodies) that can be expressed in vivo. To demonstrate, an H3 lysine 9 acetylation specific mintbody (H3K9ac-mintbody) was engineered and stably expressed in human cells. In good agreement with the localization of its target acetylation, H3K9ac-mintbody was enriched in euchromatin, and its kinetics measurably changed upon treatment with a histone deacetylase inhibitor. We also generated transgenic fruit fly and zebrafish stably expressing H3K9ac-mintbody for in vivo tracking. Dramatic changes in H3K9ac-mintbody localization during Drosophila embryogenesis could highlight enhanced acetylation at the start of zygotic transcription around mitotic cycle 7. Together, this work demonstrates the broad potential of mintbody and lays the foundation for epigenetic analysis in vivo.

Binding of Drosophila maternal Mamo protein to chromatin and specific DNA sequences.

Alterations in chromatin structure dynamically occur during germline development in Drosophila and are essential for the production of functional gametes. We had previously reported that the maternal factor Mamo, which contains both a BTB/POZ domain and C2H2 zinc-finger domains and is enriched in primordial germ cells (PGCs), is required for the regulation of meiotic chromatin structure and the production of functional gametes. However, the molecular mechanisms by which Mamo regulates germline development remained unclear. To evaluate the molecular function of Mamo protein, we have investigated the binding of Mamo to chromatin and DNA sequences. Our data show that Mamo binds to chromatin and specific DNA sequences, particularly the polytene chromosomes of salivary gland cells. Overexpression of Mamo affected the organization of polytene chromosomes. Reduction in maternal Mamo levels impaired the formation of germline-specific chromatin structures in PGCs. Furthermore, we found that the zinc-finger domains of Mamo directly bind to specific DNA sequences. Our results suggest that Mamo plays a role in regulating chromatin structure in PGCs.

Effect of renal impairment on the pharmacokinetics of memantine.

The effect of renal impairment on the pharmacokinetics of a single oral dose of memantine (10 mg) was determined in Japanese subjects. Subjects were assigned to four groups based on baseline creatinine clearance (CL(CR)): normal renal function (> 80 mL/min, n = 6), and mild (50 to ≤ 80 mL/min, n = 6), moderate (30 to < 50 mL/min, n = 6), and severe renal impairment (5 to < 30 mL/min, n = 7). Mean memantine maximum plasma concentration (C(max)) was similar in the groups (12.66, 17.25, 15.75, and 15.83 ng/mL, respectively), as was mean time to C(max) (6.2, 5.2, 4.3, and 5.4 h, respectively). However, exposure to memantine determined from mean area under the plasma concentration-time curve was 1.62-, 1.97-, and 2.33-times higher in subjects with mild, moderate, and severe renal impairment, respectively, as compared to controls with normal renal function. Mean memantine plasma elimination half-life increased according to increasing renal impairment (61.15, 83.00, 100.13, and 124.31 h, respectively), while mean cumulative urinary recovery of unchanged memantine in 72 h after dosing decreased according to increasing renal impairment (33.68%, 33.47%, 23.60%, and 16.17%, respectively). These results are the same as those in the previous study on caucasian individuals, when compared per body weight. It is suggested that the dose of memantine should be halved in patients with renal impairment.

Occurrence and clinicotopographical correlates of brainstem infarction in patients with diabetes mellitus.

BACKGROUND: The goal of the study was to clarify the association between diabetes mellitus (DM) and brainstem infarctions (BSIs) and to investigate the clinicotopographic characteristics of BSIs in patients with diabetes. METHODS: Data were retrospectively reviewed for 1026 consecutive patients admitted to our hospital because of acute cerebral infarctions from January 2004 to August 2010. Acute symptomatic BSIs were explored on radiologic images and classified into multiple infarctions with BSIs, multifocal BSIs, and monofocal BSIs. Isolated BSIs were further classified based on the vertical distribution into midbrain, pontine, and medullary infarctions, and on the horizontal distribution into anterior-dominant, posterior-dominant, and anterior/posterior BSIs. Neurologic symptoms of BSIs and clinical background were compared between DM and non-DM patients. RESULTS: The prevalence of BSIs was 2.6-fold higher (P < .0001) in DM patients. Logistic regression analysis including age, sex, smoking, previous stroke, atrial fibrillation, other cardiac diseases, hypertension, hyperlipidemia, and DM showed that DM was independently associated with BSIs (odds ratio [OR] 2.814; 95% confidence interval [CI] 1.936-4.090; P < .0001). Compared with non-DM patients, DM patients showed more frequent monofocal BSIs (P < .0001) and multifocal BSIs (P = .0296). Monofocal BSIs (n = 114) more frequently involved the pons (P < .0001) and medulla (P = .0212). Anterior-dominant BSIs (P < .0001) were more common in DM patients than in non-DM patients. Symptoms of BSIs included more frequent motor paresis (P = .0180) and less frequent diplopia (P = .0298) in DM patients than in non-DM patients. CONCLUSIONS: DM is important in the development of BSIs, and the associated clinical characteristics include more frequent motor paresis and less frequent diplopia.

Deep white matter hyperintensities, decreased serum low-density lipoprotein, and dilative large arteriopathy.

Deep white matter hyperintensities (DWMHs) seen on magnetic resonance imaging (MRI) are thought to reflect small-vessel diseases (SVDs) and may have a background that differs from that of stenotic large-vessel diseases. We assessed risk factors for DWMHs and investigated the association between DWMHs and dilative changes in the basilar artery (BA) on MRI in nonstroke patients. We reviewed clinical information and MRI findings for 149 outpatients aged 46-90 years, excluding those with a previous symptomatic cerebrovascular event. DWMHs were graded 0-3, and the maximal BA diameter and area were measured from the flow void on axial T2-weighted MRI to assess dilatation. We divided the patients into groups with and without DWMH grade 2 or 3, and compared clinical information and BA parameters in these groups. The two groups demonstrated significant differences in age, serum low-density lipoprotein (LDL) level, estimated glomerular filtration rate (eGFR), and BA parameters. An adjusted logistic regression analysis including BA diameter found that age (odds ratio [OR], 1.974 per 10 years; 95% confidence interval [CI], 1.030-1.112; P = .0006), LDL (OR, 0.811 per 10 mg/dL; 95% CI, 0.964-0.965; P = .0085), eGFR (OR, 0.835 per 10 mL/min/1.73 m(2); 95% CI, 0.967-0.998; P = .0229), and BA diameter (OR, 2.515 per 1 mm; 95% CI, 1.191-4.098; P = .0119) were independently associated with the presence of DWMHs. An analysis including the BA area yielded similar results. DWMHs are manifestations of SVDs and show a strong association with lower serum LDL level, lower eGFR, and BA dilatation.

The brainstem is at high risk for recurrent noncardioembolic cerebral infarction in association with diabetes mellitus: a hospital-based study.

The goals of the study were to investigate the importance of brainstem infarction (BSI) in recurrent noncardioembolic ischemic stroke and to examine the relevant clinical background. Data were retrospectively reviewed for 655 consecutive patients with acute noncardioembolic infarction who were admitted to our hospital from January 2004 to August 2010. The patients were divided into first-stroke (n = 592) and recurrent-stroke (n = 63) groups. Acute infarcted lesions were explored on MRI, and clinical background factors including age, sex, smoking, atrial fibrillation, coronary heart disease, hypertension, hyperlipidemia and diabetes mellitus (DM) were assessed. The frequency of BSI in the recurrent-stroke group was significantly higher than that in first-stroke patients (30.2 vs. 14.9%, p = 0.0033). No other clinical background factors differed between the two groups. Only the frequency of DM differed significantly among four subgroups formed based on stroke recurrence and BSI (p < 0.0001): DM was present in 63.2% of recurrent-stroke patients with BSI, 54.5% of first-stroke patients with BSI, 27.4% of first-stroke patients without BSI, and 20.5% of recurrent-stroke patients without BSI. We conclude that the brainstem is at high risk for recurrent cerebral infarction in patients with DM.

Innexin2 gap junctions in somatic support cells are required for cyst formation and for egg chamber formation in Drosophila.

Germ cells require intimate associations with surrounding somatic cells during gametogenesis. During oogenesis, gap junctions mediate communication between germ cells and somatic support cells. However, the molecular mechanisms by which gap junctions regulate the developmental processes during oogenesis are poorly understood. We have identified a female sterile allele of innexin2 (inx2), which encodes a gap junction protein in Drosophila. In females bearing this inx2 allele, cyst formation and egg chamber formation are impaired. In wild-type germaria, Inx2 is strongly expressed in escort cells and follicle cells, both of which make close contact with germline cells. We show that inx2 function in germarial somatic cells is required for the survival of early germ cells and promotes cyst formation, probably downstream of EGFR pathway, and that inx2 function in follicle cells promotes egg chamber formation through the regulation of DE-cadherin and Bazooka (Baz) at the boundary between germ cells and follicle cells. Furthermore, genetic experiments demonstrate that inx2 interacts with the zero population growth (zpg) gene, which encodes a germline-specific gap junction protein. These results indicate a multifunctional role for Inx2 gap junctions in somatic support cells in the regulation of early germ cell survival, cyst formation and egg chamber formation. Inx2 gap junctions may mediate the transfer of nutrients and signal molecules between germ cells and somatic support cells, as well as play a role in the regulation of cell adhesion.

Cerebral microbleeds and dilative remodeling of the basilar artery: a magnetic resonance imaging study.

This study was conducted to examine the relationship between cerebral microbleeds (CMBs), one of the manifestations of small-vessel diseases (SVDs), and basilar artery (BA) dilatation on magnetic resonance imaging (MRI). Clinical information and MRI images were reviewed for 149 outpatients aged 46-90 years, excluding those who had a previous symptomatic cerebrovascular event. CMBs were evaluated on T2∗-weighted MRI, and BA diameters were measured as the maximal width of the flow void on axial T2-weighted MRI to assess dilatation. Patients were divided into 2 groups, with CMBs and without CMBs, and clinical information and BA diameters were compared between the groups. Regression analyses of the data also were performed. The 2 groups had significant differences in mean blood pressure (MBP), low-density lipoprotein (LDL) and uricemic acid levels, and BA diameter. Adjusted logistic regression analysis showed that MBP (odds ratio [OR], 1.059 per 1 mm Hg; 95% confidence interval [CI], 1.019-1.101; P = .0035), LDL (OR, 0.976 per 1 mg/dL; 95% CI, 0.960-0.994; P = .0072), and BA diameter (OR, 3.266 per 1 mm; 95% CI, 1.504-7.103; P = .0028) each had an independent association with the presence of CMB. Adjusted multiple regression analysis showed that only BA diameter (ß coefficient, 0.240; 95% CI, 0.775-3.734; P = .0031) was independently associated with the number of CMBs. Our data indicate that CMB, a manifestation of SVD, shows a strong association with BA dilatation.

Involvement of the basilar artery in diabetes mellitus: an MRI study of brainstem infarctions.

The relationships among diabetes mellitus (DM), brainstem infarctions (BSIs) and involvement of the basilar artery (BA) were investigated in 254 patients with acute cerebral infarctions detected on magnetic resonance (MR) imaging. Radiological findings included lesion topography and size (mm(2)) of BSIs on MR images, and the extent of BA stenosis measured by MR angiography. Adjusted logistic regression analyses showed that DM (OR 4.018; p = 0.0006) and BA stenosis (OR 1.003 per 1 mm; p < 0.0001) had an independent association with the incidence of BSIs, but the lesion size of the BSIs was only associated with BA stenosis (ß coefficient 0.280; p < 0.0001). Diabetic patients showed significantly more frequent isolated pontine infarctions and a lesser degree of BA stenosis (p < 0.005) compared to non-diabetic patients. Preferential involvement of the pons and smaller vessels may be characteristics of diabetic patients.

Impact of fibroblast growth factor 23 on lipids and atherosclerosis in hemodialysis patients.

Levels of fibroblast growth factor (FGF) 23, a phosphatonin, are frequently elevated in patients with end-stage renal disease (ESRD) who are on maintenance hemodialysis (MHD). However, the role of FGF23 remains unclear because renal FGF receptor function might be impaired. The present cross-sectional study examines a cohort of patients (n = 196) on MHD who were not undergoing therapy with lipid-lowering drugs including sevelamer. Non-fasting venous blood samples were withdrawn before the hemodialysis (HD) session on the third day after the previous HD session to measure serum levels of albumin, calcium (Ca), phosphate (P), alkaline phosphatase, intact parathyroid hormone (PTH), total cholesterol (C), high-density lipoprotein (HDL)-C, low-density lipoprotein(LDL)-C, oxidative LDL-C, high-sensitivity C-reactive protein (HsCRP), interleukin-6 (IL-6), and FGF23. Nutritional status was assessed using the geriatric nutritional risk index (GNRI). Carotid intima-medial thickness (CIMT) was assessed using a B-mode ultrasound scanner. FGF23 was positively correlated with P, Ca(alb)xP product, and intact PTH, and inversely correlated with C and non-HDL-C. In the higher FGF23 tertile, levels of both non-HDL-C and C were significantly decreased and CIMT was less elevated compared to the lower FGF23 tertile. Multivariate analysis showed that the higher FGF23 tertile was independently associated with decreases in C (adjusted r(2) = 0.14) and non-HDL-C (adjusted r(2) = 0.20) levels and with a less-pronounced increase in CIMT (adjusted r(2) = 0.14). High FGF23 appears to be an independent biomarker of a decrease in C and non-HDL-C that is negatively associated with atherosclerosis in patients on MHD.

Oxidized high-density lipoprotein is associated with protein-energy wasting in maintenance hemodialysis patients.

BACKGROUND AND OBJECTIVES: Oxidized HDL (oxHDL) may behave as proinflammatory HDL because of reduced anti-inflammatory capacity and is considered a risk factor for mortality in patients on maintenance hemodialysis (MHD). The study presented here assessed the effect of oxHDL on protein-energy wasting (PEW) in MHD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This prospective study examined a cohort of MHD patients (n = 176) who were not taking lipid-lowering drugs. Blood samples were obtained to measure albumin, lipids, high-sensitivity C-reactive protein (hsCRP), oxidized LDL (oxLDL), and oxHDL. PEW was assessed by subjective global assessment (SGA) and geriatric nutritional risk index (GNRI). Measurements and assessment of nutritional status were followed up 1 year later. RESULTS: OxHDL was significantly increased in patients with PEW at baseline. High oxHDL and high hsCRP were significantly associated with PEW, and receiver operating characteristic curves for oxHDL and hsCRP showed statistically similar accuracy for predicting SGA-positive status. According to multivariate regression models, high oxHDL had a significant influence on PEW in patients, particularly those with high hsCRP. Decreased changes in GNRI and high prevalence of SGA-positive status at 1 year were more common in patients with high oxHDL at baseline and 1 year later than in patients with low oxHDL at both time points. CONCLUSIONS: A high oxHDL state may be associated with PEW estimated by GNRI and SGA, particularly concomitant with inflammation in MHD patients.

Novel markers of left ventricular hypertrophy in uremia.

AIMS: Left ventricular hypertrophy (LVH) is the most frequent cardiac complication in chronic renal disease. Previous studies implicate elevated serum phosphorus as a risk factor for LVH. METHODS: We treated 5/6 nephrectomized rats with enalapril or enalapril + sevelamer carbonate for 4 months to determine if sevelamer carbonate had an additional beneficial effect on the development of LVH and uremia-induced left ventricle (LV) remodeling. RESULTS: Uremia increased LV weight and cardiomyocyte size. Enalapril and enalapril + sevelamer blunted the increase in left ventricular weight. Only enalapril + sevelamer diminished the increase in cardiomyocyte size. Uremia increased cyclin D2 and PCNA and decreased p27 protein expression in the heart. Enalapril + sevelamer diminished the decrease in p27 expression caused by uremia. Uremia increased Ki67-positive and phosphohistone H(3)-positive interstitial cells. This was not seen in cardiomyocytes. Multivariable regression analysis showed that increased phosphorus was an independent risk factor for both increased LV weight and cardiomyocyte size. CONCLUSIONS: These data suggest left ventricular remodeling consists of cardiomyocyte hypertrophy and interstitial cell proliferation, but not cardiomyocyte proliferation. p27 and cyclin D2 may play important roles in the development of LVH. In addition, phosphorus can be an independent risk factor for the development of LVH.

Intracranial dilative arteriopathy is associated with chronic kidney disease and small vessel diseases in the elderly.

OBJECTIVE: We sought to determine the responsible factors and clinical significance of dilatation of the internal carotid artery (ICA) and basilar artery (BA). METHODS: ICA and BA diameters were measured using magnetic resonance imaging (MRI) and their association with age, sex, conventional atherosclerotic factors, and estimated glomerular filtration rate (eGFR) were evaluated in 175 outpatients aged 40 to 89 years. The arterial diameters were measured as the maximal width of the flow void on T2-weighted MRI around the brainstem. The relationship between the arterial diameters and deep white matter hyperintensities (DWMHs) on MRI graded from 0 to 3 was also examined. Comparisons were performed between groups with diameters smaller and larger than the mean value for younger (40-69 years) and older (70-89 years) patients, and multiple regression analysis was conducted. RESULTS: Age differed significantly between the larger- and smaller-diameter groups in younger patients, but not in older patients. The larger-diameter group of older patients had a significantly lower eGFR (P = .0002 for ICA, P = .0035 for BA) and a higher DWMH grade (P = .0021 for ICA, P < .0001 for BA) compared to the smaller-diameter group. In multiple regression analysis adjusted for age and sex, a lower eGFR was an independent factor associated with larger arterial diameters (P = .0002 for ICA, P = .0021 for BA). CONCLUSION: Kidney dysfunction is an independent factor that is related to ICA and BA dilatation, which is also associated with DWMHs that reflect small vessel diseases in older patients.

Dilative arterial remodeling of the brain with different effects on the anterior and posterior circulation: an MRI study.

OBJECTIVE: The goal of the study was to investigate factors associated with dilation of the internal carotid artery (ICA) and basilar artery (BA), which reflect the anterior and posterior circulation respectively, and to examine if these arteries are affected differently by specific factors. METHODS: The diameters of ICA and BA were measured using T2-weighted magnetic resonance (MR) images at the level of the brainstem in 304 outpatients, with the maximal width of the flow void taken as the diameter for each artery. The association between the diameters and clinical data including hemoglobin A1c (HbA1c) and estimated glomerular filtration rate (eGFR) was investigated. The same analysis was performed for the BA/ICA ratio. RESULTS: Multiple regression analysis adjusted for confounding factors including gender and age showed that a lower eGFR was independently associated with dilation of both the ICA (beta coefficient -0.148, P=0.0135) and the BA (beta -0.219, P=0.0007). HbA1C was independently associated with a greater BA/ICA ratio (beta -0.183, P=0.0015) but eGFR did not show this association. Diabetes mellitus was significantly more frequent (P=0.0353) in patients with a BA/ICA ratio higher than the mean, compared to those with a lower BA/ICA ratio. CONCLUSION: Kidney dysfunction was shown to be a dilative factor for the anterior and posterior circulation as reflected by the ICA and BA diameters, respectively. The association of the BA/ICA ratio with HbA1c suggests that diabetes mellitus may affect each circulation differently.

Ultrapure dialysate influences serum myeloperoxidase levels and lipid metabolism.

BACKGROUND: Ultrapure dialysate (UD) might contribute to improvements in the morbidity and mortality of hemodialysis (HD) patients. However, it is unclear whether increasing dialysate purity affects chronic inflammation, oxidative stress, and lipid abnormalities. METHODS: In a prospective cohort study, 126 patients undergoing maintenance HD using conventional dialysate (CD) with one endotoxin cut filter were assigned to either continuation of the same HD or HD using UD (more purified dialysate). At baseline and 6 months we measured lipids, high-sensitive (hs)CRP, oxidative LDL-cholesterol, and myeloperoxidase. RESULTS: Serum myeloperoxidase and hsCRP levels in the UD group were significantly decreased at 6 months compared with the CD group. Multivariate analysis showed that decreases in non-HDL-cholesterol and ApoB at 6 months were independently correlated with changes in myeloperoxidase. CONCLUSION: Endotoxin-free UD can improve the chronic inflammatory status, oxidative stress, and lipid abnormalities, suggesting a possible contribution to reduced cardiovascular disease risk and ultimately to lowered mortality in HD patients.

Assessment of myeloperoxidase and oxidative alpha1-antitrypsin in patients on hemodialysis.

BACKGROUND AND OBJECTIVES: The present study assesses the effects of the oxidative stress marker, myeloperoxidase (MPO), and the possible MPO-related oxidative stress marker, oxidative alpha(1)-antitrypsin (oxAT), on carotid intima-media thickness (CIMT) and protein-energy wasting (PEW) in patients on hemodialysis (HD). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Blood samples were obtained from 383 patients before HD to measure WBC count, serum albumin, lipids, high-sensitivity C-reactive protein (CRP), alpha(1)-antitrypsin (AT), interleukin-6, oxidative LDL-C, MPO, and oxAT. We assessed both CIMT and the geriatric nutritional risk index (GNRI) in this cross-sectional competitive study. RESULTS: Levels of MPO and oxAT correlated. Myeloperoxidase was associated with max-CIMT, and oxAT correlated with max-CIMT and GNRI. Multivariate linear regression models showed that MPO and oxAT were independent predictors of increasing max-CIMT, whereas oxAT, but not MPO, independently correlated with GNRI. In four combined MPO and oxAT groups classified according to median values, a multinomial logistic regression model showed that high MPO together with high oxAT was independently associated with increased max-CIMT. Moreover, the OR for max-CIMT with positive PEW and high MPO was significantly increased in the four groups with combined MPO and PEW. CONCLUSIONS: High MPO with high oxAT and high MPO with PEW seem to contribute to plaque formation in patients on HD, whereas elevated MPO or oxAT alone might not predict increasing CIMT. In contrast, a high oxAT value seems to be an independent predictor of PEW in patients on HD.