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WO3 and silicone rubber (SR)-based gasochromic composites were fabricated to detect hydrogen leaks at room temperature. WO3 rod-like nanostructures were uniformly distributed in the SR matrix, with a particle size of 60-100 nm. The hydrogen permeability of these composites reached 1.77 cm3·cm/cm2·s·cmHg. At a 10% hydrogen concentration, the visible light reflectance of the composite decreased 49% during about 40 s, with a color change rate of 6.4% s-1. Moreover, the composite detected hydrogen concentrations as low as 0.1%. And a color scale was obtained for easily assessing hydrogen concentrations in the environment based on the color of composites. Finally, the composite materials as disposable sensors underwent testing at several Sinopec hydrogen refueling stations.
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In this study, the influences of mulberry leaf extract (MLE) addition on the physicochemical properties including the specific volume, texture and sensory features of white bread (WB) were evaluated by the sensory analysis technology. A double-blind, randomised, repeat-measure design was used to study the impact of MLE addition on the postprandial blood glucose response as well as the satiety index of WB. Results showed that the addition of MLE showed no significant effects on the physicochemical properties of WB except for the slight changes of color and bitterness. The addition of MLE significantly reduced the total blood glucose rise after ingestion of WB over 120 minutes, and reduced the GI value of WB in a dose-effect relationship. When the concentration of MLE reached 1.5 g per 100 g available carbohydrate, the GI value of WB could be reduced from 77 to 43. This study provides important information in terms of the appropriateness of MLE when added to more complex real food, the dose-dependent relationship could supply a reference for the application of MLE.
Subject(s)
Bread , Glycemic Index , Morus , Plant Extracts , Blood Glucose/analysis , Blood Glucose/drug effects , Bread/adverse effects , Cross-Over Studies , Glycemic Index/drug effects , Insulin , Morus/chemistry , Plant Extracts/pharmacology , Postprandial Period , Triticum , Double-Blind Method , HumansABSTRACT
Induced pluripotent stem cells (iPSCs) have been the focus of cellular therapy studies. The use of iPSCs in regenerative medicine is limited by their tumorigenic potential. This study sought to determine whether iPSCs-derived podocytes attenuate acute kidney injury (AKI) and the molecular mechanism. Inoculation of iPSCs-podocytes significantly promoted the repair of kidney injury in AKI mice, reduced the levels of kidney injury factors Scr, BUN, and urinary NAG, and alleviated the inflammatory response. Histological analysis revealed a significant increase in the number of M2 macrophages and a significant decrease in M1 macrophages in the kidney tissues. Subsequently, the genes and signaling pathways that may be associated with kidney injury repair in mice were analyzed by RNA-seq and bioinformatics prediction. The polarization of M2 macrophages was promoted by MAF bZIP transcription factor B (Mafb)-mediated activation of C-C motif chemokine receptor 5 (Ccr5) and nicotinamide phosphoribosyltransferase (Nampt) signaling pathway. Taken together, these results show that iPSCs-podocytes depend on Mafb to activate the Nampt signaling pathway through transcriptional activation of Ccr5, thereby promoting the repair of AKI caused by ischemia-reperfusion.
Subject(s)
Acute Kidney Injury , Induced Pluripotent Stem Cells , Podocytes , Reperfusion Injury , Mice , Animals , Induced Pluripotent Stem Cells/metabolism , Nicotinamide Phosphoribosyltransferase/metabolism , Podocytes/metabolism , Macrophages/metabolism , Acute Kidney Injury/pathology , Kidney/metabolism , Reperfusion Injury/metabolism , MafB Transcription Factor/genetics , MafB Transcription Factor/metabolismABSTRACT
Background: Elderly patients exhibit a higher incidence of chronic heart failure (CHF). Patients with CHF can develop acute kidney injury (AKI) during follow-up, which can result in poor prognosis. This relationship between kidney dysfunction and levels of N-terminal pro-brain natriuretic peptides (NT-proBNP), with regard to prognosis, is complicated and has rarely been analyzed in elderly patients with CHF. Method: We conducted a retrospective cohort study involving patients with a CHF history aged ≥ 65 years, who experienced an episode of AKI. Kaplan-Meier curves and Cox or logistic proportional hazards regression models were used to evaluate the association between serum NT-proBNP concentrations and mortality or renal recovery by day 90. Results: A total of 1,160 eligible patients with AKI were available for the study. Of this sample, 41.5% of patients died within 90 days of the onset of AKI. Patients with a decreased change in NT-proBNP accompanying the episode of AKI had a lower risk (adjusted OR = 0.56, 95% CI = 0.34-0.91) of more severe AKI (stage 2 and 3 vs. stage 1). The more severe AKI were associated with higher mortality and non-recovery of renal function in elderly patients with CHF, independent of NT-proBNP levels. Elevated levels of baseline lnNT-proBNP (adjusted HR = 1.27, 95% CI = 1.17-1.38) predicted mortality in elderly patients with CHF within 90 days of AKI onset. Patients with a decrease in NT-proBNP accompanying AKI had a lower risk of mortality (adjusted HR = 0.62, 95% CI = 0.48-0.79). However, a decrease in NT-proBNP is a risk factor (adjusted OR = 1.59, 95% CI = 1.02-2.48) for the non-recovery of renal function following AKI-especially in elderly survivors with low baseline NT-proBNP levels. Conclusion: A decreased change in NT-proBNP maybe protective for elderly patients with CHF by improving survival outcomes and preventing severe AKI. However, an excessive decrease in NT-proBNP is a risk factor for the non-recovery of renal function following AKI. Avoiding excessive changes in NT-proBNP may be protective for survival and renal injury prognosis.
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The risk of fire in the chemical industry's production process is fatal. Gel foam has been widely employed in petroleum storage tanks, oil pools, and other petrochemical equipment for fire extinguishing and thermal protection. Recently, nanoparticles have been doped into gel foam to enhance thermal stability and insulation. However, heat transfer behaviors of the gel foam layer containing nanoparticles are still missing. In this study, a numerical heat transfer model of a gel foam layer containing silica nanoparticles under a radiative heat flux was established. Through simulation, the changes in foam thickness and temperature distribution were analyzed. The effects of the maximum heating temperature, initial gas content, nanoparticle size, and concentration on the thermal insulation behavior of the gel foam layer were systematically studied. The results showed that the thermal stability and insulation performance of the three-phase gel foam layer decreased with the increase in the initial gas content and particle size. Increasing the nanoparticle concentration could enhance the foam's thermal stability and insulation performance. The results provide guidance for a designing gel foam with high thermal protection performance.
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INTRODUCTION: While patients with diabetes are at higher risk of developing acute kidney injury (AKI), there are few studies on the recurrence of AKI in older adult patients. This study therefore aimed to examine the impact of diabetes on AKI recurrence and long-term outcomes in older male patients. METHODS: This retrospective cohort study included older male patients who experienced AKI during hospitalization from July 2007 to August 2011. Medical records of all patients were followed up for 10 years. Patients with AKI were classified into groups with and without diabetes. We analyzed differences in common geriatric comorbidities, AKI recurrence frequency, and severity between the two groups, identified risk factors affecting recurrence frequency, and assessed outcomes. RESULTS: Of all 266 patients, 128 had diabetes and 138 did not. The AKI recurrence rate was significantly higher in the group with diabetes (80.5 vs. 66.7%; P = 0.011). There was a significantly higher proportion of AKI caused by infections in patients with diabetes (43.3 vs. 33.2%, P = 0.006). The proportion of patients with an AKI recurrence frequency ≥ 3 was significantly higher in the group with diabetes (44.7 vs. 29.4%, P = 0.027). Diabetes and coronary heart disease were independent risk factors for AKI recurrence (P < 0.05), diabetes control was associated with multiple AKI recurrences (P = 0.016), and no significant difference was found between the groups regarding the 10-year prognosis (P = 0.522). However, a subgroup analysis showed that patients with multiple AKI recurrences within 2 years had the worst survival outcome (P = 0.004). CONCLUSIONS: Older male patients with diabetes are prone to AKI recurrence after initial onset of AKI. Diabetes is an independent risk factor for AKI recurrence, and active diabetes control (HbA1c < 7%) may thus reduce the recurrence of AKI and improve the very poor outcomes of patients with multiple recurrences of AKI within 2 years.
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In this study, the effect of corn oligopeptides (COPs) with liver protection activity on mice with hepatic fibrosis (HF) induced by carbon tetrachloride (CCl4 ) was studied. It was proved that COPs can ameliorate the liver injury and inflammation caused by CCl4 by histopathology and enzyme-linked immunosorbent assay in mice. The expression of Akt/NF-κB inflammatory pathway was determined by real-time polymerase chain reaction (RT-PCR) and western blotting (WB). The results showed that COPs inhibited the expression of key proteins in the inflammatory pathway. In conclusion, the results of this study suggested that COPs could improve CCl4 -induced HF by improving liver injury, reducing the expression of inflammatory factors, and inhibiting the expression of inflammatory signaling pathways. PRACTICAL APPLICATIONS: The corns around the world are mainly used as animal feed, and the liver protective activity of corn oligopeptides (COPs) is rarely applied to the market. The development of COPs liver protective food can prevent the occurrence of liver-related diseases such as hepatic fibrosis to a certain extent. Developing COPs liver protecting food can improve the utilization value of corn. It is hoped that this study can provide experimental support for the application of COPs in liver protection food.
Subject(s)
NF-kappa B , Proto-Oncogene Proteins c-akt , Animals , Liver Cirrhosis/chemically induced , Liver Cirrhosis/drug therapy , Mice , NF-kappa B/genetics , NF-kappa B/metabolism , Oligopeptides/pharmacology , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Zea mays/metabolismABSTRACT
Background: In patients with acute heart failure (AHF) coexisting with oliguria, high doses of loop diuretics are often ineffective in increasing urine output and may adversely affect the patient's prognosis, especially in elderly patients. We investigated the efficacy of adding tolvaptan (TLV) on improving the prognosis in elderly patients with AHF coexisting with oliguria. Methods: All data for this retrospective cohort study were extracted from the electronic medical record system of the Second Medical Center of Chinese PLA General Hospital from January 2018 to December 2020. Patients diagnosed with AHF coexisting with oliguria were enrolled in this study and were divided into TLV and non-TLV groups based on the use of TLV. The primary outcome was all-cause mortality at 7 and 90-day. The secondary outcomes were the remission of AHF within 7 and 30 days or continued progression of AHF, and new-onset chronic kidney disease (CKD) after 90 days. Cox proportional hazards regression was used to assess the relationships between all-cause mortality and diuretic regimens, demographics, laboratory parameters, comorbidities, and medications. Results: A total of 308 patients met the study criteria for the final statistical analysis, and they had a median age of 91 years (88, 95). The results showed that the addition of TLV was associated with a decreased risk of the 7 and 90-day all-cause mortality in patients with AHF with oliguria [adjusted HR, 95% CI: 0.60 (0.37, 0.98), p = 0.042; 0.56 (0.41, 0.75), p < 0.001, respectively]. Adding TLV significantly increased urine output and decreased N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in 7 days, and alleviated the progression of AHF within 30 days. There were no statistically significant differences between the patients with or without TLV in terms of the occurrence of hypernatremia, the development of hepatic impairment within 30 days, and new-onset CKD after 90 days. Conclusions: This study demonstrated that the addition of TLV was clinically effective in increasing urine output, and had favorable effects on alleviating AHF progression and may reduce the risk of all-cause mortality at 7 and 90-day in elderly patients with AHF with oliguria, and TLV had a good safety profile. Trial registration: http://www.chictr.org.cn/showprojen.aspx?proj=148046, identifier: ChiCTR2200055518.
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BACKGROUND: Food allergy is a serious public nutritional health problem that has attracted extensive worldwide attention. Shellfish allergy is a long-lasting disorder that has a lifelong impact on health. Sarcoplasmic calcium-binding protein (SCP) plays a vital role in cell and muscle functions and has been identified as an allergen in oyster. RESULTS: In this study, recombinant SCP (rSCP) with a molecular mass of 21 kDa was produced and identified based on SCP amino acid sequencing of Pacific oyster (Crassostrea gigas), and was used as a follow-up experimental material. Its physicochemical characterization showed that purified rSCP is highly stable to heat and acid-alkali and trypsin digestion but less resistant to pepsin digestion. We established an animal sensitization model and rSCP displayed stronger Immunoglobulin E (IgE)-binding activity with rat serum in the rSCP + cholera toxin (CT) group compared with the CT group and a control group. Five epitope peptides were identified as linear immunodominant epitopes by indirect competitive enzyme-linked immunosorbent assay (icELISA) for the first time. We also found that conformational epitopes may play a major role in the immunoreactivity of SCP. CONCLUSION: These results are significant for understanding hypersensitization of humans to oyster and offer available preventive measures and treatment programs in further research. © 2021 Society of Chemical Industry.
Subject(s)
Allergens , Crassostrea , Allergens/chemistry , Allergens/genetics , Amino Acid Sequence , Animals , Calcium-Binding Proteins/chemistry , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/metabolism , Crassostrea/genetics , Epitopes/chemistry , RatsABSTRACT
BACKGROUND: Molluscan shellfish, including oysters, often cause allergic reactions in sensitive people throughout the world. It has been demonstrated that arginine kinase (AK) is one of the major allergens of oyster. The present study aimed to evaluate the immunoreactivity and structure of oyster AK as affected by heat treatment, pH change, and in vitro digestion. What is more, the immunoglobulin E-binding epitopes of this allergen were also predicted and validated. RESULTS: Thermal and pH assays revealed that AK was unstable at temperature >40 °C or pH ≤5.0 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and circular dichroism, and the digestibility assays suggested that AK was more easily digested by pepsin than by trypsin and chymotrypsin. The potential epitopes were predicted through immunoinformatics tools, and seven linear epitopes were identified by indirect competition enzyme-linked immunosorbent assay with pooled sera and individual serum from oyster-allergic patients. The critical amino acids in each epitope were also confirmed using mutant peptides. These linear epitopes and critical amino acids were apt to distribute on the outer surface of homology-based AK model. Moreover, the three denaturants (sodium dodecyl sulfate, ß-mercaptoethanol, and urea) can destroy the spatial structure of AK and increase or reduce its allergenicity by denaturation treatments. CONCLUSION: Processing conditions lay the foundation for the variation of allergenicity. Seven linear epitopes and their critical amino acids were identified by indirect competitive enzyme-linked immunosorbent assay. These findings will be helpful in allergy diagnosis and development of hypoallergenic products in the near future. © 2021 Society of Chemical Industry.
Subject(s)
Arginine Kinase , Crassostrea , Allergens/chemistry , Amino Acid Sequence , Amino Acids , Animals , Arginine Kinase/chemistry , Arginine Kinase/metabolism , Epitopes/chemistry , Humans , Sodium Dodecyl SulfateABSTRACT
BACKGROUND: The renal artery plays a central role in renal perfusion and is critical for proper renal function. Ageing is an independent risk factor for both impaired renal function and vascular disorders, and associated with an increase in the expression of the vasoconstrictor endothelin-1 (ET-1), and caloric restriction (CR) without malnutrition has been shown to be an effective inhibitor of renal dysfunction induced by ageing. The objective of this study was to determine whether CR-mediated alleviation of renal dysfunction is mediated by ET-1 expression. METHODS: The young (2 months, 2 M) and old (12 months, 12 M) Sprague-Dawley male rats were used and fed ad libitum. The 12-month-old rats were further divided into 12 M and 12 M-caloric restriction (CR) (30% calorie restriction). After 8 weeks, the renal tissues were showed by PAS staining, and age-related metabolic parameters and renal functions were detected in each group of rats. The inflammatory cytokines of interleukin (IL)-6, IL-1ß, tumor necrosis factor alpha (TNF-α), and transforming growth factor beta 1 (TGF-ß1) were analyzed using ELISA. The mRNA and protein expression in the renal artery were analysis by qRT-PCR and Immunoblot analysis. RESULTS: Ageing was associated with significant increases in 24 h urine protein content and serum triglyceride and cholesterol in 12 M rats, both of which were significantly inhibited in 12 M-CR. The mRNA expression and the secretion of IL-6, IL-1ß, TNF-α, and TGF-ß1 in the renal artery was significantly increased with ageing and inhibited by CR. CR also inhibited ageing-induced Edn1 (encoding ET-1) mRNA and protein expression in the renal artery. In addition, CR could regulate ET-1 expression by inhibiting the activation of NF-κB signaling and activation and induction in the expression of NF-E2-related factor 2 (Nrf2) and histone deacetylase and gene repressor sirtuin 1 (SIRT1), both of which play a central role in mitigating oxidative stress in young rats. CONCLUSIONS: Moderate CR can reverse the ageing related kidney dysfunction by reducing the ET-1 expression. CR might be used as an alternative to prevent the ageing induced renal artery dysfunction.
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This study investigated the effectiveness of bio-augmenting aerobic cell culture to mitigate ammonia and hydrogen sulfide emission in sewage sludge composting amended with reed straw (with the weight ratio of 1:0.3-0.4). During the 20-day aerated lab-scale composting, adding 200-mL culture (56.80 NTU) reduced ammonia and hydrogen sulfide emissions by 38.00% and 54.32%, and conserved total nitrogen and sulfate by 39.42% and 70.75%, respectively. Organic matters degradation was quick started 1 day ahead. Comparing to the control, nitrate content increased 38.75% at the end of the compost. Bioaugmentation evened the distributions of bacterial communities in the thermophilic phase. The shift was mainly due to 22.97% of relative abundance of Proteobacteria depressed and 157.16% of Bacteroidetes increased, which were beneficial for nitrogen conservation and glycan breakdown, respectively. In summary, the results demonstrated that bioaugmentation addition could be an effective strategy for enhanced sludge composting.
Subject(s)
Composting , Hydrogen Sulfide , Ammonia , Nitrogen/analysis , Sewage , SoilABSTRACT
OBJECTIVE: To investigate the effect of Shexiang Baoxin Pill (, SBP) on early hypertensive renal injury in rats and to explore the possible mechanism. METHODS: Twelve-week-old spontaneous hypertensive rats (SHRs) with high-salt diet (dietary containing 8% NaCl) were randomized into the SBP group [40 mg/(kg·d)], losartan potassium group [20 mg/(kg·d)] and saline group by stratified random sampling method, 12 in each group. Blood pressure and urea albumin creatinine ratio were measured. After 10 weeks, the expression levels of serum creatinine (Scr), hypersensitive C-reactive protein (hs-CRP), interleukin (IL)-1 ß, IL-6, tumor necrosis factor α (TNF-α), and transforming growth factor ß (TGF-ß) in serum were assessed. Kidney pathology periodate-schiff staining was performed. Semi-quantitative count of macrophage infiltration was determined by immunochemistry of CD68 staining. Real-time quantitative polymerase chain reaction and Western blot were performed to examine the mRNA and protein expressions of Toll-like receptor 4 (TLR4), nuclear factor κB (NF-κB), monocyte chemokine peptide (MCP-1), inducible nitric oxide synthase (iNOS), and arginase-1 (Arg-1). RESULTS: SBP did not affect the mortality of SHR (P<0.05). SBP significantly reduced the level of elevated blood pressure of SHRs, but the effect was less significantly than that of losartan potassium. SBP decreased urine protein (P<0.01) and the expression levels of IL-1 ß, IL-6, TNF-α, and TGF-ß in serum. The 22-week-old SHRs showed mild proliferation of glomerular endothelial cells, glomerular ischemic lesions, inflammatory cell infiltration in renal tubular interstitium and arteriosclerosis. Both SBP and losartan potassium had alleviated renal pathological change, and significantly reduced the infiltration of macrophage (P<0.05, P<0.01). SBP and losartan potassium decreased the expressions of TLR4, NF-κB, MCP-1, iNOS, and Arg-1. CONCLUSION: SBP significantly modified the early hypertensive renal injury by reducing inflammation, and the effect was similar to losartan potassium.
Subject(s)
Hypertension , Animals , Drugs, Chinese Herbal , Endothelial Cells , Hypertension/drug therapy , Kidney , Rats , Rats, Inbred SHRABSTRACT
The Yellow River Delta is the largest and youngest estuarine and coastal wetland in China and is experiencing the most active interactions of seawater and freshwater in the world. Bacteria played multifaceted influence on soil biogeochemical processes, and it was necessary to investigate the intermodulation between the soil factors and bacterial communities. Soil samples were collected at sites with different salinity degree, vegetations, and interference. The sequences of bacilli were tested using 16S rRNA sequencing method and operational taxonomic units were classified with 97% similarity. The soil was highly salinized and oligotrophic, and the wetland was nitrogen-restricted. Redundancy analysis suggested that factors related with seawater erosion were principal to drive the changes of soil bacterial communities and then the nutrient level and human disturbance. A broader implication was that, in the early succession stages of the coastal ecosystem, seawater erosion was the key driver of the variations of marine oligotrophic bacterial communities, while the increasing nutrient availability may enhance in the abundance of the riverine copiotrophs in the late stages. This study provided new insights on the characteristics of soil bacterial communities in estuarine and coastal wetlands.
Subject(s)
Soil , Wetlands , Bacteria/genetics , China , Ecosystem , Humans , Nutrients , RNA, Ribosomal, 16S/genetics , Rivers , SalinityABSTRACT
To investigate the effects of the water-sediment regulation on the spatial variations of metals in the surface sediments of the Yellow River Estuary (YRE), sampling sites were set in 2015 (51 sites in June and 33 in October). The content of Cu, Pb, Cd, Cr, Zn, Ni and Mn was determined using inductively coupled plasma spectrometry and of Hg and As atomic fluorescence spectrometry. The results showed that the concentrations of metals in the sediments of YRE were lower after the regulation, while that of most metals increased in the tidal areas of the current estuary with fine particles. Environmental pollution and ecological risk of metals were mainly from Hg and Cd. Metals carried with the silt of the river should be focused. The findings were expected to update the current status of metal pollution of YRE and be helpful for the delicacy management of the regime and silt-laden rivers.
Subject(s)
Arsenic/analysis , Geologic Sediments/analysis , Metals, Heavy/analysis , Water Pollutants, Chemical/analysis , Wetlands , China , Environmental Monitoring/methods , Environmental Policy , Estuaries , Geologic Sediments/chemistry , Rivers/chemistryABSTRACT
This study aimed to examine the effects of atorvastatin on early hypertensive renal damage and explored the underlying mechanisms. 12-week-old salt-loaded spontaneous hypertensive rats (SHRs) were divided into four groups: atorvastatin (AVT), losartan potassium (LP), atorvastatin combined with peroxisome proliferators-activated receptor γ (PPAR-γ) inhibitor (AVT + GW9662), and saline. During 10 weeks administration blood pressure and urea albumin creatinine ratio were determined. We also examined the renal function, pathological changes of kidney, inflammatory cytokines in the serum and the association of the change of inflammatory factors in the kidney tissue. AVT did not reduce the mortality of the SHRs. AVT reduced the blood pressure of SHRs, but the effect was not comparable to that of LP. AVT significantly decreased urine protein. AVT and LP displayed comparable effects by significantly decreasing inflammatory cytokines (hs-CRP, IL-1ß, IL-6, TNF-α, and TGF-ß) levels in serum. AVT and LP both apparently improved renal pathological changes and significantly reduced the infiltration of macrophage in renal tubular interstitial. Both mRNA and protein expression levels of TLR4, NFκB, MCP-1 were significantly down regulated in AVT and LP groups. There was no significant change in macrophage polarity. The addition of PPAR-γ inhibitor partially reduced the anti-inflammatory effect of AVT. These results mean that Atorvastatin can alleviates the pathology of hypertensive renal damage. Atorvastatin protects the kidney by reducing the apparent inflammation in salt-loaded SHRs. Atorvastatin alleviates inflammation partially by augmenting expression of PPAR-γ.
Subject(s)
Atorvastatin/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hypertension/drug therapy , Inflammation Mediators/antagonists & inhibitors , Kidney Diseases/drug therapy , Animals , Atorvastatin/pharmacology , Blood Pressure/drug effects , Blood Pressure/physiology , Female , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Hypertension/metabolism , Hypertension/pathology , Inflammation Mediators/metabolism , Kidney Diseases/metabolism , Kidney Diseases/pathology , Male , Rats , Rats, Inbred SHRABSTRACT
The Yellow River Delta is the most intact estuary wetland in China and suffers from great pressure of metals. Seventy-seven surface sediment samples were collected in the delta, and contents of Cu, Pb, Cd, Cr, Zn, Ni, and Mn were analyzed by inductively coupled plasma spectrometry and those of Hg and As by atomic fluorescence spectrometry. The results showed that means of metal contents (ppm, dry weight) were as follows: Hg, 0.04; Cr, 61.72; Cu, 20.97; Zn, 60.73; As, 9.47; Pb, 21.91; Cd, 0.12; Ni, 27.24; and Mn, 540.48. 43.8% of Hg and 14.3% of Cd were from the allogenic source while others from the authigenic source. The results of the geoaccumulation indexes appeared that 6.5% of sites from the estuarine and the Gudao areas were moderately polluted by Hg. All ecological risk index values of Hg and 37.7% of Cd were more than 40, which were the main factors of strongly and moderately potential ecological risks of 37.7% of sites in the delta. High Cd contents may be due to the alkaline conditions of the delta and the unreasonable management of the farmland, while the abnormal distribution of Hg to the wet or dry deposition and the erosion of the seawater. It was suggested to monitor Hg content in the atmosphere of the Yellow River Delta. The results were expected to update the pollution status of metals in the delta and created awareness of preserving the sound condition of the Yellow River Delta.
Subject(s)
Environmental Monitoring , Geologic Sediments , Metals, Heavy , China , Risk Assessment , Rivers , Water Pollutants, ChemicalABSTRACT
OBJECTIVE: To investigate the effects of atorvastatin (AVT) on renal function and renal pathological changes in the aged rat and explore their possible mechanisms. METHODS: Twenty-month-old, normal female Wistar rats were divided into three groups: group A (n=8) was fed high-dose AVT (10mg/kg/d); group B (n=8) was fed low-dose AVT (1mg/kg/d); and group C (controls, n=8) received the same volume of normal saline; 3-month-old, normal female Wistar rats served as young normal controls (n=8). All rats were sacrificed following a 4-month treatment period. Serum creatinine and blood lipid levels were measured. The glomerular sclerosis index and tubulointerstitial lesions were determined using renal periodic acid-Schiff-stained paraffin sections. The mRNA and protein expressions of matrix metalloproteinases (MMP)-9 and -2, tissue inhibitors of metalloproteinase (TIMP)-1 and -2, transforming growth factor-ß1 (TGF-ß1), and peroxisome proliferator-activated receptors (PPARs) were examined using reverse transcription polymerase chain reactions and Western blots, respectively. RESULTS: Serum lipid (including serum cholesterol and serum triglycerides) levels in aged rats were significantly higher than those in young rats (p<0.05). Compared to the aged control group, high-dose AVT was associated with significantly lower serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels in aged rats (p<0.05); low-dose AVT was associated only with lower serum LDL-C levels (p<0.05). Renal morphological changes in aged rats included focal glomerulosclerosis, infiltration of inflammatory cells, and arteriole sclerosis. Improved renal pathology was observed in aged, AVT-treated rats, and included a decreased glomerular sclerosis index and tubulointerstitial lesion score, especially in those receiving high-dose AVT. Additionally, renal artery wall thickening, luminal narrowing, and arteriolosclerosis were significantly less severe in aged rats receiving high-dose AVT. Upregulated expression of MMP-9 and TGF-ß1 was observed in the renal tissue of aged rats. AVT treatment was associated with a reversal of these phenomena and upregulated expression of TIMP-1, PPARα, PPARß, and PPARγ in aged rats. CONCLUSION: AVT improved the renal pathology of aged rats. These effects may have been induced by the lowering of blood lipids, maintaining the MMP/TIMP balance, and downregulating the expression of TGF-ß1. AVT may reduce the levels of MMP-9 and TGF-ß in aged rats by upregulating the expression of PPARs.