Single-cell RNA sequencing reveals transdifferentiation of parathyroid chief cells into oxyphil cells in patients with uremic secondary hyperparathyroidism.

The parathyroid gland is one of the main organs that regulate calcium and phosphorus metabolism. It is mainly composed of chief cells and oxyphil cells. Oxyphil cell counts are low in the parathyroid glands of healthy adults but are dramatically increased in patients with uremia and secondary hyperparathyroidism (SHPT). Increased oxyphil cell counts are related to drug treatment resistance, but the origin of oxyphil cells and the mechanism of proliferation remain unknown. Herein, three types of parathyroid nodules (chief cell nodules, oxyphil cell nodules and mixed nodules, respectively) excised from parathyroid glands of uremic SHPT patients were used for single-cell RNA sequencing (scRNA-seq), other molecular biology studies, and transplantation into nude mice. Through scRNA-seq of parathyroid mixed nodules from three patients with uremic SHPT, we established the first transcriptomic map of the human parathyroid and found a chief-to-oxyphil cell transdifferentiation characterized by gradual mitochondrial enrichment associated with the uremic milieu. Notably, the mitochondrial enrichment and cellular proliferation of chief cell and oxyphil cell nodules decreased significantly after leaving the uremic milieu via transplantation into nude mice. Remarkably, the phenotype of oxyphil cell nodules improved significantly in the nude mice as characterized by decreased mitochondrial content and the proportion of oxyphil cells to chief cells. Thus, our study provides a comprehensive single-cell transcriptome atlas of the human parathyroid and elucidates the origin of parathyroid oxyphil cells and their underlying transdifferentiating mechanism. These findings enhance our understanding of parathyroid disease and may open new treatment perspectives for patients with chronic kidney disease.

Integrated transcriptomic and proteomic analyses for the characterization of parathyroid oxyphil cells in uremic patients.

Chief cells are the predominant cells in parathyroid glands of healthy adults; however, parathyroid oxyphil cells, whose function is unknown, increase dramatically in patients with secondary hyperparathyroidism (SHPT). Calcitriol and calcimimetics are the most powerful treatments for SHPT, while the mechanisms leading to calcitriol or calcimimetic resistance in oxyphil cell-predominant SHPT are unknown. Here we used transcriptomic and proteomic techniques to characterize oxyphil cells by comparing the differences between chief and oxyphil cell nodules of parathyroid glands in uremic patients. Compared to chief cell nodules, the most marked expression increases in oxyphil cell nodules were for mitochondrion-associated proteins. The mitochondria number and mitochondrial DNA content were also significantly increased in oxyphil cell nodules. Moreover, oxyphil cell nodules expressed parathyroid-specific factors, and exhibited lower levels of proliferation-related proteins but higher synthesis and secretion level of parathyroid hormone (PTH). The protein expression of SHPT-regulating factors, including vitamin-D receptor, calcium-sensing receptor and Klotho, were significantly downregulated in oxyphil cell nodules. Therefore, oxyphil cells characterized by enrich mitochondria in uremic patients showed higher synthesis and secretion of PTH but lower expression of SHPT regulators than chief cells, which may contribute to the pathophysiology of SHPT and the treatment resistance to calcitriol and calcimimetics.

Early Renal-Replacement Therapy May Reduce the All-Cause Mortality of Severe COVID-19: An Observational Cohort Study.

INTRODUCTION: The efficacy of renal-replacement treatment (RRT) remains to be validated in COVID-19. In this retrospective cohort study, we aimed to assess the efficacy of early initiation of RRT in intensive care unit (ICU) adults with severe COVID-19. METHODS: Fifty-eight adult patients in ICU with critically ill or severe COVID-19 with a tendency of critical illness were recruited from February 9, 2020, to March 30, 2020. Early RRT were determined by the ICU medical team based on boom in cytokines levels, increased organs injury/failure, and rapid aggravation of condition. All participants were followed up from the first day of ICU admission to March 30, 2020. The primary outcome was all-cause mortality in ICU. RESULTS: The mean age of the cohort was 68.4 ± 14.6 years, with 81.0% having at least one comorbidity before hospitalization. Twenty patients (34.5%) initiated early RRT after 24.1 ± 10.4 days from the onset and 6.4 ± 3.6 days from ICU admission. Thirty-four of 58 participants (58.6%) died during ICU follow-up. Univariate and multivariate Cox proportional-hazards model showed that early RRT was associated with a lower risk of all-cause mortality in ICU with an adjusted HR of 0.280 (95% CI: 0.106-0.738, p = 0.010). Sudden unexpected death (SUD) was remarkably reduced in the early RRT group, compared with the control group (0.2 vs. 2.9 per 100 person-day, p = 0.02). CONCLUSION: Early RRT can reduce the all-cause in-hospital mortality, especially SUD in patients with severe COVID-19, but not improve multi-organ impairment or increase the risk of AKI. Early initiation of RRT merits an optional strategy in critically ill patients with COVID-19 (ChiCTR2000030773).

The Utility of Rise in Red Cell Distribution Width in Determining the Risk of Renal Relapse in Lupus Nephritis.

BACKGROUND: We hypothesized that the levels of red cell distribution width (RDW) would correlate with lupus nephritis (LN) disease activity, therapeutic response after induction therapy, and its rise would be associated with future renal relapse in patients who had achieved clinical remission. METHODS: The associations of RDW and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), renal response, and renal relapse after induction therapy were examined in 172 biopsy-proven LN patients at the Division of Nephrology, Huashan Hospital Fudan University between 2007 and 2017. RESULTS: The median RDW of LN patients was significantly higher than that of healthy individuals (p < 0.001). Baseline RDW demonstrated positive correlation with baseline SLEDAI (r = 0.239, p = 0.004). Overall RDW after induction treatment was significantly decreased (p = 0.005), especially in the complete remission (CR) group (p = 0.02), and the partial remission (PR) group had a decreasing trend (p = 0.09), while the change of RDW in the no response (NR) group was not statistically significant (p = 0.70). Among the 153 patients who achieved remission after induction therapies, 37 (24.2%) patients developed 42 episodes of subsequent renal flare during a median follow-up of 36.0 (IQR, 20 - 66) months. The median time from remission to renal flare was 18.0 (IQR, 7.0 - 45.0) months. The overall renal flare rate was 0.065 relapse per patient-year. During follow up, 54 RDW rises (defined as more than 0.5% increase in RDW) were identified. There were 33 episodes (61.1%) of renal flares in patients with RDW rises, while there were only 9 renal flares (8.65%) in 104 patients without RDW rise (p < 0.001). Survival analysis showed that RDW rise was associated with a significantly higher risk of future renal relapse (adjusted HR, 14.03; 95% CI, 5.29 to 37.20; p < 0.001). CONCLUSIONS: In addition to correlating with disease activity and therapeutic response to induction therapy in patients with LN, RDW rise is a significant predictor of future renal relapse in patients who achieve remission.

Complete remission of nephrotic syndrome in a young woman with anti-LRP2 nephropathy after immunosuppressive therapy.

BACKGROUND: Anti-low density lipoprotein receptor-related protein 2 (LRP2) nephropathy/anti-brush border antibody (ABBA) disease is a disorder characterized by acute tubulointerstitial injury associated with circulating antibodies to kidney proximal tubular brush border protein LRP2/megalin. Patients are typically elderly and present with acute kidney injury and subnephrotic proteinuria. They progress to end-stage renal disease with poor response to immunosuppressive therapies. CASE PRESENTATION: We report a case of a 29-year-old Chinese woman, who presented with nephrotic syndrome with normal kidney function. Kidney biopsy showed no obvious tubular injury or interstitial inflammation. Positive immunoglobulin G (IgG) staining was revealed along the brush border of proximal tubular cells. Anti-LRP2 antibody was identified in serum, consistent with a diagnosis of anti-LRP2 nephropathy. The patient achieved complete remission after receiving prednisone and cyclophosphamide. CONCLUSIONS: Anti-LRP2 nephropathy can also present as nephrotic syndrome in young patients and complete remission from nephrotic syndrome may be achieved after immunosuppressive therapy.

EGF Receptor-Dependent YAP Activation Is Important for Renal Recovery from AKI.

BACKGROUND: Increasing evidence indicates that renal recovery from AKI stems from dedifferentiation and proliferation of surviving tubule epithelial cells. Both EGF receptor (EGFR) and the Hippo signaling pathway are implicated in cell proliferation and differentiation, and previous studies showed that activation of EGFR in renal proximal tubule epithelial cells (RPTCs) plays a critical role in recovery from ischemia-reperfusion injury (IRI). In this study, we explored RPTC activation of Yes-associated protein (YAP) and transcriptional coactivator with PDZ binding motif (TAZ), two key downstream effectors of the Hippo pathway, and their potential involvement in recovery from AKI. METHODS: We used immunofluorescence to examine YAP expression in kidney biopsy samples from patients with clinical AKI and controls (patients with minimal change disease). Studies of RPTC activation of YAP and TAZ used cultured human RPTCs that were exposed to hypoxia-reoxygenation as well as knockout mice (with inducible deletions of Yap, Taz, or both occurring specifically in RPTCs) that were subjected to bilateral IRI. RESULTS: YAP was activated in RPTCs in kidneys from post-AKI patients and post-IRI mouse kidneys. Inhibition of the interaction of YAP and the TEA domain (TEAD) transcription factor complex by verteporfin or conditional deletion of YAP in RPTCs delayed renal functional and structural recovery from IRI, whereas TAZ deletion had no effect. Activation of the EGFR-PI3K-Akt pathway in response to IRI signaled YAP activation, which promoted cell cycle progression. CONCLUSIONS: This study shows that EGFR-PI3K-Akt-dependent YAP activation plays an essential role in mediating epithelial cell regeneration during kidney recovery from AKI.

Plasma Aß42:Aß40 ratio as a biomarker for cognitive impairment in haemodialysis patients: a multicentre study.

Background: Mild cognitive impairment (MCI) and dementia are more prevalent in patients undergoing haemodialysis (HD). Although the cerebrospinal fluid amyloid beta (Aß) and tau (τ) have proven to be valid biomarkers for the diagnosis of Alzheimer's disease (AD) in the general population, the roles of plasma Aß and τ for the diagnosis of cognitive impairment in HD patients remain unknown. Methods: We conducted a cross-sectional study including patients receiving HD in three hospitals in Shanghai. All patients completed the Montreal Cognitive Assessment-Basic (MoCA-B). To validate the effectiveness of the MoCA-B score for screening MCI, a subset group underwent neuropsychological batteries. Serum proteomes were compared in HD patients with normal cognitive function and dementia. Plasma Aß42, Aß40 and total τ were measured using a single molecule array. Results: A total of 311 HD patients were enrolled (mean age 63 years, 55% male). The best cut-off score of MoCA-B for differentiating MCI and normal cognition was 24, with an area under the curve of 0.94. Serum proteomics revealed that neurodegenerative pathways related to AD were enriched in HD patients with dementia. The plasma Aß42:Aß40 ratio was significantly reduced in patients with MCI and dementia and was independently associated with cognitive function after adjusting for age, sex and education levels. Conclusions: We validated the MoCA-B as an optimal cognitive function screening instrument for MCI in HD patients. The plasma Aß42:Aß40 ratio was a potential biomarker in distinguishing normal cognition, MCI and dementia in HD populations.

Bromodeoxyuridine Methodology for Labeling Renal Stem Cells During Kidney Development of Mice.

A continuous Bromodeoxyuridine (BrdU) labeling approach was used during the whole process of the mice kidney development to explore the best BrdU-labeling time, the distribution of BrdU-retaining cells, and to probe into the niche of stem cells in adult kidney. BrdU was injected intraperitoneally to the mice once daily for 3 consecutive days from day 11.5 of embryonic period (E11.5) to the postnatal day 21.5 (P21.5). The kidneys were harvested 24 h after the last BrdU injection and 6 months of age. A renal injury model of subtotal nephrectomy (Nx) in adult mice treated with BrdU was used to observe the response of BrdU-retaining cells to renal injury. When BrdU labeled at E11.5-13.5, the BrdU-retaining cells were mainly detected in the papilla and inner medulla in adult mice. When BrdU labeled at P0.5-11.5, the BrdU-retaining cells were mainly detected in the inner medulla and outer medulla. When BrdU labeled at P12.5-17.5, the BrdU-retaining cells were mainly detected in the outer medulla. When BrdU labeled at P18.5-21.5, almost no BrdU-positive cells could be found, except the cortex. Seventy-two hours after Nx operation in adult mice by BrdU-labeling at P0.5-2.5 or P15.5-17.5, a significant increase of BrdU-retaining cells was found in many cortical proximal tubules, while a dramatic decrease was detected in medulla near the incision edge. Moreover, most of BrdU-positive cells were not costained with proliferating cell nuclear antigen. The distributions of label-retaining cells in the mice kidney were different if BrdU was administered in different periods of kidney development. Most of BrdU-retaining cells were quiescent, the proximal tubules were the only segments that always contained BrdU positive cells, which may have the niche of stem cells in adult kidney.

High sodium reduced the expression of PTH1R and Klotho by inhibiting 1,25(OH)2D3 synthesis in cultured proximal tubule epithelial cells.

Background: The proximal tubule is the sensing site of sodium and phosphate and the main place for the synthesis and metabolism of 1,25(OH)2D3. We aimed to investigate the effects of high sodium on the synthesis and function of active vitamin D and local phosphate regulation in proximal tubular epithelial cells. Methods: Human proximal tubule epithelial (HK-2) cells were treated with different concentrations of sodium/phosphate. The expression of 1α-OHase and 24-OHase was determined. Liquid chromatography/mass spectrometry (LC/MS) and enzyme-linked immunosorbent assay (ELISA) were used to detect the levels of 1,25(OH)2D3. RNA sequencing and bioinformatics analysis was used to probe into the possible pathways. Chromatin samples were immunoprecipitated with antibodies against parathyroid receptor 1 (PTH1R) and Klotho. Results: We found that high sodium decreased the expression of 1,25(OH)2D3 by reducing 1α-OHase and 24-OHase, reduced the expression of PTH1R and Klotho, and increased the intracellular calcium concentration. These effects were reversed by sodium phosphate transporter inhibitor, sodium hydrogen transporter inhibitor, and a chelator of the extracellular calcium, whereas enhanced by ouabain. Vitamin D receptor (VDR) agonists significantly increased the recruitment of VDR to the vitamin D response element (VDRE) of PTH1R and Klotho promoter, thus increasing the expression of PTH1R and Klotho. Conclusions: High sodium can decrease the synthesis of active vitamin D in the proximal tubules, affect the gene regulation of 1,25(OH)2D3/VDR, and significantly reduce the expression of PTH1R and Klotho. It revealed the influence of a high-sodium diet on mineral metabolism and the core role of vitamin D in kidney mineral metabolism.

The ratio of CRP to prealbumin levels predict mortality in patients with hospital-acquired acute kidney injury.

BACKGROUND: Animal and human studies suggest that inflammation and malnutrition are common in acute kidney injury (AKI) patients. However, only a few studies reported CRP, a marker of inflammation, albumin, prealbumin and cholesterol, markers of nutritional status were associated with the prognosis of AKI patients. No study examined whether the combination of inflammatory and nutritional markers could predict the mortality of AKI patients. METHODS: 155 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. C-reactive protein (CRP), and the nutritional markers (albumin, prealbumin and cholesterol) measured at nephrology consultation were analyzed in relation to all cause mortality of these patients. In addition, CRP and prealbumin were also measured in healthy controls (n = 45), maintenance hemodialysis (n = 70) and peritoneal dialysis patients (n = 50) and then compared with AKI patients. RESULTS: Compared with healthy controls and end-stage renal disease patients on maintenance hemodialysis or peritoneal dialysis, patients with AKI had significantly higher levels of CRP/prealbumin (p < 0.001). Higher level of serum CRP and lower levels of albumin, prealbumin and cholesterol were found to be significant in the patients with AKI who died within 28 days than those who survived >28 days. Similarly, the combined factors including the ratio of CRP to albumin (CRP/albumin), CRP/prealbumin and CRP/cholesterol were also significantly higher in the former group (p < 0.001 for all). Multivariate analysis (Cox regression) revealed that CRP/prealbumin was independently associated with mortality after adjustment for age, gender, sepsis and sequential organ failure assessment (SOFA, p = 0.027) while the others (CRP, albumin, prealbumin, cholesterol, CRP/albumin and CRP/cholesterol) became non-significantly associated. The hazard ratio was 1.00 (reference), 1.85, 2.25 and 3.89 for CRP/prealbumin increasing according to quartiles (p = 0.01 for the trend). CONCLUSIONS: Inflammation and malnutrition were common in patients with AKI. Higher level of the ratio of CRP to prealbumin was associated with mortality of AKI patients independent of the severity of illness and it may be a valuable addition to SOFA score to independent of the severity of illness and it may be a valuable addition to SOFA score to predict the prognosis of AKI patients.

High-phosphorus diet controlled for sodium elevates blood pressure in healthy adults via volume expansion.

Whether increasing exposure to dietary phosphorus can lead to adverse clinical outcomes in healthy people is not clear. In this open-label prospective cross-over study, we are to explore the impact of various dietary phosphorus intake on mineral, sodium metabolisms and blood pressure in young healthy adults. There were 3 separate study periods of 5 days, each with a 5 days washout period between different diets interventions. Six young healthy male volunteers with normal nutrition status were recruited in Phase I Clinical Research Center and sequentially exposed to the following diets: (a) normal-phosphorus diet (NPD): 1500 mg/d, (b) low-phosphorus diet (LPD): 500 mg/d, (c) high-phosphorus diet (HPD): 2300 mg/d. HPD induced a significant rise in daily average serum phosphate (1.47 ± 0.02 mmol/L [4.56 ± 0.06 mg/dl]) compared to NPD (1.34 ± 0.02 mmol/L [4.15 ± 0.06 mg/dL]) and LPD (1.17 ± 0.02 mmol/L [3.63 ± 0.06 mg/dL]) (p < .05). Daily average levels of serum parathyroid hormone and fibroblast growth factor 23 in HPD were significantly higher, and serum 1,25(OH)2 D3 was remarkably lower than those in LPD. HPD induced a significant decrease in daily average serum aldosterone and an increase in daily average atrial natriuretic peptide level compared to LPD. The 24-hour urine volume in HPD subjects was less than that in LPD subjects. HPD significantly increased daily average systolic blood pressure by 6.02 ± 1.24 mm Hg compared to NPD and by 8.58 ± 1.24mm Hg compared to LPD (p < .05). Our study provides the first evidence that 5-day high-phosphorus diet can induce elevation in SBP in young healthy adults, which may due to volume expansion.

Mannitol is an independent risk factor of acute kidney injury after cerebral trauma: a case-control study.

We retrospectively studied a random cohort of patients with cerebral trauma to investigate the risk factors of acute kidney injury (AKI) following cerebral trauma. AKI was determined using the RIFLE (risk, injury, failure, loss, or end-stage kidney) staging criteria. About 171 patients were chosen in the study, with 53 patients in AKI group and 118 patients without AKI in non-AKI group. By logistic regression analysis, univariate analysis revealed that age, hypertension, emergent surgery, systemic inflammatory response syndrome (SIRS), Glasgow coma score (GCS), sequential organ failure assessment (SOFA) score, the respiration, coagulation, and cardiovascular components of the SOFA score, mechanical ventilation time, red blood cell transfusion, plasma transfusion, and the accumulative doses of furosemide, torsemide, and mannitol were significantly related to AKI after cerebral trauma. Logistic multivariate regression analysis showed that SOFA score [odds ratio (OR) = 1.516, 95% confidence interval (CI) 1.222-1.881, p < 0.001], the accumulative doses of torsemide (OR = 0.016, 95% CI 1.002-1.031, p = 0.016), and the accumulative doses of mannitol (OR = 2.687, 95% CI 1.062-6.800, p = 0.037) were independent risk factors of AKI. This model had a good discrimination for AKI with an area under the receiver operating characteristic (ROC) curve of 0.901 (p < 0.001). The accumulative doses of mannitol as a risk factor of AKI were identified by propensity score match (PSM) method. We concluded that AKI was a common complication in patients with cerebral trauma. SOFA score and the accumulative doses of torsemide and mannitol were independent risk factors of AKI following cerebral trauma.

Intima-media thickness of the carotid artery and its correlation factors in maintenance hemodialysis patients: a cross-sectional study.

BACKGROUND: To investigate the relationship between the intima-media thickness of the carotid artery (CA-IMT) and its major risk factors in maintenance hemodialysis (MHD) patients. METHODS: Seventy-five MHD patients and 30 healthy volunteers were enrolled. The MHD patients were divided into 3 subgroups according to their CA-IMT value. RESULTS: CA-IMT values in the MHD group were significantly higher than those in the control group. The differences in age, systolic blood pressure (SBP), and levels of serum albumin, prealbumin, cholesterol and serum phosphate between the increased IMT group and the normal IMT group were significant. SBP and serum phosphate levels were also greater in the abnormal IMT group than those in the normal IMT group. Significant relationships were found between CA-IMT and age, SBP, and serum levels of phosphate, albumin and prealbumin. In multiple regression analysis, a high serum phosphate level, low serum prealbumin level and high SBP were significant independent risk factors of increased CA-IMT. CONCLUSIONS: CA-IMT was increased dramatically in MHD patients. A high serum phosphate level, low serum prealbumin level and high SBP may be associated with advanced arteriosclerosis.

Advanced oxidation protein products induce vascular calcification by promoting osteoblastic trans-differentiation of smooth muscle cells via oxidative stress and ERK pathway.

Vascular calcification is an actively regulated process similar to bone formation. Advanced oxidation protein products (AOPPs) have been demonstrated to be novel markers of oxidant-mediated protein damage. The present study investigated the role of AOPPs in inducing osteoblastic trans-differentiation and calcification of smooth muscle cells in vitro. We found that AOPPs directly increased the calcium deposition and expression of core binding factor-alpha1 (CBF-alpha1) and osteopontin (OPN) and significantly decreased SM-alpha-actin expression in human aortic smooth muscle cells (HASMCs). AOPPs increased intracellular oxidative stress, which was inhibited by vitamin E. Vitamin E also inhibited AOPP-induced calcium content and osteoblast differentiation of HASMCs. Furthermore, the inhibitor of ERK significantly suppressed the effects of AOPPs on calcification and osteoblast marker expression. These findings suggest that AOPPs induce vascular calcification by promoting osteoblast differentiation of smooth muscle cells via oxidative stress and ERK pathway.

Effects of HELP therapy on acute ischemic stroke and vascular endothelial cell function.

To evaluate the therapeutic effects of the HELP system (heparin-induced extracorporeal low-density lipoprotein-apolipoprotein(a)-fibrinogen precipitation) in patients with acute ischemic stroke and probe into its possible mechanism, 10 patients with acute ischemic stroke were included in this study and received the HELP therapy in addition to low molecular weight dextran, salvia miltiorrhiza and aspirin. Matched with gender, age, European Stroke Scale (ESS) and fibrinogen, 20 patients with cerebral infarction treated with low molecular heparin were chosen as controls during the same period. We compared the efficacy and prognosis between the two groups. In order to clarify the effects of HELP treatment on endothelial function, human umbilical vein endothelial cells (HUVEC) were cultured with the serum of pre- and post-HELP therapy and control patients, then endothelial permeability and biomarkers of endothelial dysfunction or activation in the supernatant of incubated HUVEC, such as soluble thrombomodulin (sTM), soluble intracellular adhesion molecule-1 (sICAM-1) and monocyte chemoattractant protein-1 (MCP-1), were tested. Twenty-one days after treatment, ESS scores in the HELP group (70.4 +/- 23.06) were higher than those in control group (60.7 +/- 18.94), but there was no statistical significance (P > 0.05). In the HELP group, total efficacy rate reached 60% with ESS score (6 cases of recovery and efficacy, 4 cases of inefficacy), while it was 40% in control group (8 cases of recovery and efficacy, 12 cases of inefficacy), but unfortunately there was no significant difference between both groups using the chi(2)-test (P > 0.05). Interestingly, with the activities of daily living (ADL) score, the efficacy rate in the HELP group (60%) was markedly higher than that in the control group (20%) (P < 0.05). Furthermore, Pearson correlation analysis showed that the therapeutic window (the time from the patient's onset to receiving the therapy) was correlated to final ADL scores (P = 0.044) and the mean therapeutic window was 14.08 +/- 3.41 h in patients who achieved efficacy criteria. After therapy, no difference was found in hemorheology, fibrinogen, blood lipid, oxidized low-density lipoprotein (oxLDL) or C-reactive protein (CRP) in the control group, while there was a significant decrease in the HELP group immediately after treatment (P < 0.01). But the hospital stay time was similar between the HELP group and the controls (23.11 +/- 10.65 vs. 21.53 +/- 8.73 days; P > 0.05) and 21 days later, the dimension of the largest cross-sectioned infarction area by CT scan did not significantly change for the two groups' of patients (P > 0.05). When cultured with the patient's serum after HELP therapy, the concentration of sTM, sICAM-1, and MCP-1 in the supernatant of cultured HUVEC remained unchanged at 24 h (P > 0.05), while it was remarkably higher when HUVEC was cultured with the serum of the controls and patients before HELP therapy (P < 0.01), except for sTM. The endothelial permeability was also improved after the HELP treatment. With the effects of improving hemorheology, decreasing acute phase reactive proteins such as CRP and fibrinogen, ameliorating endothelial cell function, HELP system may be a novel therapy for acute ischemic stroke.

Citrate Pharmacokinetics in Critically Ill Patients with Acute Kidney Injury.

INTRODUCTION: Regional citrate anticoagulation (RCA) is gaining popularity in continous renal replacement therapy (CRRT) for critically ill patients. The risk of citrate toxicity is a primary concern during the prolonged process. The aim of this study was to assess the pharmacokinetics of citrate in critically ill patients with AKI, and used the kinetic parameters to predict the risk of citrate accumulation in this population group undergoing continuous veno-venous hemofiltration (CVVH) with RCA. METHODS: Critically ill patients with AKI (n = 12) and healthy volunteers (n = 12) were investigated during infusing comparative dosage of citrate. Serial blood samples were taken before, during 120 min and up to 120 min after infusion. Citrate pharmacokinetics were calculated and compared between groups. Then the estimated kinetic parameters were applied to the citrate kinetic equation for validation in other ten patients' CVVH sessions with citrate anticoagulation. RESULTS: Total body clearance of citrate was similar in critically ill patients with AKI and healthy volunteers (648.04±347.00 L/min versus 686.64±353.60 L/min; P = 0.624). Basal and peak citrate concentrations were similar in both groups (p = 0.423 and 0.247, respectively). The predicted citrate curve showed excellent fit to the measurements. CONCLUSIONS: Citrate clearance is not impaired in critically ill patients with AKI in the absence of severe liver dysfunction. Citrate pharmacokinetic data can provide a basis for the clinical use of predicting the risk of citrate accumulation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00948558.

Is the serum vitamin D level at the time of hospital-acquired acute kidney injury diagnosis associated with prognosis?

BACKGROUND: Low circulating vitamin D levels have been suggested to potentially contribute to acute complications in critically ill patients. However, in patients with acute kidney injury (AKI), whether vitamin D deficiency occurs and is a potential contributor to worse early outcomes at the time of AKI diagnosis remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: Two hundred patients with AKI were enrolled in our study. Healthy subjects and critically ill patients without AKI served as controls. Serum vitamin D concentrations were measured in the three groups. The patients with AKI were followed up for 90 days and grouped according to median serum vitamin D concentrations. In addition, vitamin D receptor polymorphisms (BsmI and FokI) were measured in these patients; they were also followed up for 90 days and grouped according to vitamin D receptor gene mutations. Low serum 1,25-dihydroxyvitamin D levels (59.56±53.00 pmol/L) were detected in patients with AKI and decreased with increasing severity of AKI. There were no significant findings with respect to 25-hydroxyvitamin D. The 90-day survival curves of individuals with high vitamin D concentrations showed no significant differences compared with the curves of individuals with low concentrations. The survival curves of patients with BB/Bb or FF/Ff genotypes also showed no significant differences compared with patients with bb or ff genotypes. In Cox regression analysis, the vitamin D status in patients with AKI was not an independent prognostic factor as adjusted by age, sex, Sequential Organ Failure Assessment score, or vitamin D receptor polymorphisms. CONCLUSIONS/SIGNIFICANCE: Patients with AKI manifested a marked decrease in the 1,25-dihydroxyvitamin D level at the time of AKI diagnosis, and the degree of 1,25-dihydroxyvitamin D deficiency increased with the severity of AKI. No association between the serum vitamin D level at the time of AKI diagnosis and 90-day all-cause mortality was found in patients with AKI.

Nitrotyrosine level was associated with mortality in patients with acute kidney injury.

BACKGROUND: To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI. METHODOLOGY/PRINCIPAL FINDINGS: 158 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. Twelve critically ill patients without AKI and 15 age and gender-matched healthy subjects served as control. Plasma 3-nitrotyrosine was analyzed in relation to 90-day all cause mortality of patients with AKI. The patients with AKI were followed up for 90 days and grouped according to median plasma 3-nitrotyrosine concentrations. Highest 3-NT/Tyr was detected in patients with AKI compared with healthy subjects, and critically ill patients without AKI (ANOVA p<0.001). The 90-day survival curves of patients with high 3-NT/Tyr showed significant differences compared with the curves of individuals with low 3-NT/Tyr (p = 0.001 by log rank test). Multivariate analysis (Cox regression) revealed that 3-NT/Tyr (p = 0.025) was independently associated with mortality after adjustment for age, gender, sepsis and Acute Physiology and Chronic Health Evaluation (APACHE) II score. CONCLUSIONS/SIGNIFICANCE: There is excess plasma protein oxidation in patients with AKI, as evidenced by increased nitrotyrosine content. 3-NT/Tyr level was associated with mortality of AKI patients independent of the severity of illness.

Twelve weeks of pioglitazone therapy significantly attenuates dysmetabolism and reduces inflammation in continuous ambulatory peritoneal dialysis patients--a randomized crossover trial.

BACKGROUND: The aim of the present study was to investigate the effect of oral pioglitazone (PIO) on lipid metabolism, insulin resistance, inflammation, and adipokine metabolism in continuous ambulatory peritoneal dialysis (CAPD) patients. METHODS: In this randomized crossover trial, 36 CAPD patients with serum triglyceride levels above 1.8 mmol/L were randomly assigned to receive either oral PIO 15 mg once daily or no PIO for 12 weeks. Then, after a 4-week washout, the patients were switched to the alternative regimen. The primary endpoint was change in serum triglycerides during the PIO regimen compared with no PIO. Secondary endpoints included changes in other lipid levels, homeostatic model assessment of insulin resistance (HOMA-IR), adipocytokines, and C-reactive protein (CRP). RESULTS: All 36 CAPD patients (age: 64 ± 11 years; 33% men; 27.8% with diabetes mellitus) completed the study. Comparing patients after PIO and no PIO therapy, we found no significant differences in mean serum triglycerides (3.83 ± 1.49 mmol/L vs 3.51 ± 1.98 mmol/L, p = 0.2). However, mean high-density lipoprotein (0.94 ± 0.22 mmol/L vs 1.00 ± 0.21 mmol/L, p = 0.004) and median total adiponectin [10.34 µg/mL (range: 2.59 - 34.48 µg/mL) vs 30.44 µg/mL (3.47 - 93.41 µg/mL), p < 0.001] increased significantly. Median HOMA-IR [7.51 (1.39 - 45.23) vs 5.38 (0.97 - 14.95), p = 0.006], mean fasting blood glucose (7.31 ± 2.57 mmol/L vs 6.60 ± 2.45 mmol/L, p = 0.01), median CRP [8.78 mg/L (0.18 - 53 mg/L) vs 3.50 mg/L (0.17 - 26.30 mg/L), p = 0.005], and mean resistin (32.70 ± 17.17 ng/mL vs 28.79 ± 11.83 ng/mL, p = 0.02) all declined. The PIO was well tolerated, with only one adverse event: lower-extremity edema in a patient with low residual renal function. CONCLUSIONS: Blood triglycerides were not altered after 12 weeks of PIO 15 mg once daily in CAPD patients, but parameters of dysmetabolism were markedly improved, including insulin resistance, inflammation, and adipokine balance, suggesting that PIO could be of value for this high-risk patient group. Larger, more definitive studies are needed to confirm these findings.