RÉSUMÉ
BACKGROUND: Microwave ablation (MWA) is an effective treatment option for patients with primary liver cancer. However, it has been reported that the MWA procedure induces a hepatic inflammatory response and injury, which may negatively affect the efficacy of MWA. As such, the discovery of reliable markers to monitor the patient's response to MWA is needed. Golgi protein 73 (GP73) has been shown to be associated with chronic liver disease. To date, the potential value of serum GP73 in the dynamic monitoring during MWA of liver cancer remains unclear. AIM: To examine the effects of MWA on the serum levels of GP73 in patients with primary liver cancer. METHODS: A total of 150 primary liver cancer patients with a single small lesion (≤ 3 cm in diameter) were retrospectively enrolled spanning the period between January 2016 and October 2018. All of the patients received MWA for the treatment of primary liver cancer. Serum GP73, alpha-fetoprotein (AFP), and widely used liver biochemical indicators [serum albumin, total bilirubin (TBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST)] were compared before MWA and at different time points, including 1, 2, and 4 wk following the ablation procedure. RESULTS: Complete tumor ablation was achieved in 95.33% of the patients at 1 mo after MWA. The 1-, 2-, and 3-year disease-free survival rates were 74.67%, 59.33%, and 54.00%, respectively. The serum AFP levels were significantly decreased at 1, 2, and 4 wk after MWA; they returned to the normal range at 12 wk after MWA; and they remained stable thereafter during follow-up in those cases without recurrence. In contrast, the serum GP73 levels were significantly increased at 1 and 2 wk after MWA. The serum GP73 levels reached the peak at 2 wk after MWA, started to decline after hepatoprotective treatment with glycyrrhizin and reduced glutathione, and returned to the pretreatment levels at 12 and 24 wk after MWA. Notably, the changes of serum GP73 in response to MWA were similar to those of TBIL, ALT, and AST. CONCLUSION: Serum GP73 is markedly increased in response to MWA of liver cancer. Thus, serum GP73 holds potential as a marker to monitor MWA-induced inflammatory liver injury in need of amelioration.
Sujet(s)
Carcinome hépatocellulaire , Tumeurs du foie , Alanine transaminase , Aspartate aminotransferases , Bilirubine , Marqueurs biologiques , Carcinome hépatocellulaire/chirurgie , Glutathion , Acide glycyrrhizique , Humains , Tumeurs du foie/chirurgie , Protéines membranaires , Micro-ondes/effets indésirables , Études rétrospectives , Sérumalbumine , Alphafoetoprotéines/métabolismeRÉSUMÉ
BACKGROUND AND PURPOSE: Enhancing phagocytosis can facilitate the removal of inflammatory molecules, limit the toxicity of dead cells and debris, and promote recovery after brain injury. In this study, we aimed to explore the role of bexarotene (Bex), a retinoid X receptor (RXR) agonist, in promoting astrocyte phagocytosis and neurobehavioral recovery after subarachnoid hemorrhage (SAH). METHODS: Mice SAH model was induced by pre-chiasmatic injection of blood. Modified Garcia score, novel object recognition, rotarod test, and Morris water maze were performed to assess neurological function. Immunofluorescence and electron microscopy were used to evaluate astrocyte phagocytosis in vivo. In additionï¼ ABCA1/MEGF10&GULP1, the primary astrocyte phagocytosis pathway, were stimulated by Bex or suppressed by HX531 (a RXR antagonist) to evaluate their impacts on astrocyte phagocytosis and neurological recovery. RESULTS: Astrocytes phagocytosis of blood components were observed in mice after SAH induction, which is further increased by Bex treatment. Bex dramatically attenuated neuroinflammation, reduced brain edema, improved early neurological performance and promoted neurocognitive recovery. Meanwhile, Bex decreased neurotoxic reactive astrocytes and preserved neurogenesis after SAH. Bex increased the expression of astrocyte phagocytosis-related proteins ABCA1, MEGF10, and GULP1. Bex also increased the lysosomal processing of engulfed blood components in astrocytes. Moreover, Bex significantly promoted astrocytes to phagocytize debris in vitro by increasing the expression of ABCA1, MEGF10 and GULP1, while HX531 inhibited astrocyte phagocytosis and decreased these protein levels. CONCLUSIONS: Bex enhanced astrocyte phagocytosis through the ABCA1-mediated pathways, and promoted neurobehavior recovery in mice after SAH induction.
Sujet(s)
Hémorragie meningée , Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP , Animaux , Astrocytes/métabolisme , Benzoates , Bexarotène/pharmacologie , Bexarotène/usage thérapeutique , Dérivés du biphényle , Modèles animaux de maladie humaine , Protéines membranaires/métabolisme , Souris , Phagocytose , Récepteurs X des rétinoïdes/agonistes , Hémorragie meningée/traitement médicamenteuxRÉSUMÉ
A shortage of freshwater resources has become a fundamental and chronic problem for sustainable agriculture development in arid regions. Use of saline water irrigation has become an important means for alleviating freshwater scarcity. However, long-term irrigation with saline water may cause salt accumulation in the soil, and further affect nitrogen transformation and N2O emission. To investigate this, we conducted a ten-year field experiment to evaluate the effect of irrigation water salinity and N amount on N2O emission and denitrifying bacterial communities. The experimental design was a 2×2 factorial with two irrigation water salinity levels (salinity levels are expressed as electrical conductivity), 0.35 dS·m-1 and 8.04 dS·m-1, and two N amounts, 0 kg·hm-2 and 360 kg·hm-2, representing SFN0, SHN0, SFN360, and SHN360, respectively. The results indicated that long-term saline water irrigation significantly increased soil salinity, moisture, and NH4+-N content, whereas it decreased soil pH, NO3--N, organic matter, and total nitrogen content. Irrigation with saline water significantly inhibited N2O emission, being associated with a decreased in level of 45.19% (unfertilized plots) and 43.50% (fertilized plots) compared with irrigation with fresh water. N2O emission increased as the N amount increased; the N2O emission was 161% higher in the fertilized plots than in the unfertilized plots. In the unfertilized plots, saline water irrigation significantly reduced the activity of denitrifying enzymes, the abundance of nirK, nirS, and nosZ, and the diversity of denitrifying bacterial communities. In the fertilized plots, saline water irrigation did not significantly affect the abundance of nosZ, whereas it significantly reduced the abundance of nirK and nirS. Saline water irrigation and nitrogen application altered the community structures of denitrifying bacteria with nirK, nirS, and nosZ; the irrigation water salinity seemed to have a greater impact on the denitrifying bacterial community in comparison with fertilization. Linear discriminant analysis (LDA) effect size (LEfSe) analysis demonstrated that denitrifying bacterial potential biomarkers increased as the water salinity increased, meaning that saline water irrigation could alter the community structures of denitrifying bacteria, and promote the growth of dominant species. Our findings indicate that increased abundance of nosZ, nirK, and nirS promoted N2O emission, and although long-term saline water reduced soil N2O emission, it resulted in a continuous increase of soil salinity. The emission of N2O had extremely positive correlation with soil NO3--N, organic matter, total nitrogen, denitrifying bacteria abundance, and denitrifying enzyme activities, and was negatively correlated with soil moisture. The soil physiochemical properties and the community structure of denitrifying bacteria had a significant influence on soil N2O emission in cotton fields, and nirS bacteria showed the highest association with N2O emission, thus it might be a dominant microflora in the process of denitrification. This information will aid in reducing atmospheric N2O emissions in agriculturally productive alluvial grey desert soils.
Sujet(s)
Protoxyde d'azote/analyse , Microbiologie du sol , Bactéries , Dénitrification , Eaux salées , SolRÉSUMÉ
A Gram-stain-negative, aerobic, motile, yellow-pigmented, rod-shaped with a single polar flagellum bacterial strain, designated strain DHG54T, was isolated from a forest soil sample of Dinghushan Biosphere Reserve, Guangdong Province, China. Strain DHG54T grew at 12-37 °C (optimum, 28 °C), pH 4.5-8.0 (optimum, pH 6.0-7.0) and in the presence of 0-3.0â% (w/v) NaCl (optimum, 0-1.5â%, w/v). Based on 16S rRNA gene sequence analysis, strain DHG54T formed a clade with the members of the genus Dyella and showed highest sequence similarities of 98.2â% to Dyella japonica DSM 16301T and Dyella terrae KACC 12748T. This was also supported by phylogenetic analysis based on the concatenated partial gyrB, lepA and recA housekeeping gene sequences. DNA-DNA hybridization results between strain DHG54T and closely related Dyella species were all lower than 70â%. Ubiquinone-8 was the only respiratory quinone, and iso-C15â:â0, iso-C17â:â0 and iso-C17â:â1 ω9c were major fatty acids. The DNA G+C content of strain DHG54T was 65.4 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. On the basis of the polyphasic characterization results presented here, strain DHG54T represents a novel species of the genus Dyella, for which the name Dyellasolisilvae sp. nov. (type strain DHG54T=GDMCC 1.1187T = LMG 30091T) is proposed.
Sujet(s)
Forêts , Phylogenèse , Microbiologie du sol , Xanthomonadaceae/classification , Techniques de typage bactérien , Composition en bases nucléiques , Chine , ADN bactérien/génétique , Acides gras/composition chimique , Hybridation d'acides nucléiques , Pigmentation , Pinus , ARN ribosomique 16S/génétique , Analyse de séquence d'ADN , Ubiquinones/composition chimique , Xanthomonadaceae/isolement et purificationRÉSUMÉ
Ursodeoxycholic acid (UDCA) is a type of hydrophilic bile acid extracted from animal bile with a wide range of biological functions. The present results demonstrated that UDCA could effectively inhibit the proliferation of two human melanoma cell line (M14 and A375) with time and concentrationdependence. Following exposure to various concentrations of UDCA, M14 cells exhibited typical morphological changes and weaker ability of colony forming. Flow cytometry analysis demonstrated that UDCA could induce a decrease of mitochondrial membrane potential and an increase in reactive oxygen species (ROS) levels in M14 cells. The cell cycle was arrested in the G2/M phase, which was confirmed by the decrease of cyclindependent kinase 1 and cyclinB1 at the protein level. However, when M14 cells were treated with UDCA and ZVADFMK (caspase inhibitor) synchronously, the apoptosis rate of the cells was reduced significantly. In addition, it was demonstrated that UDCA induced apoptosis of human melanoma M14 cells through the ROStriggered mitochondrialassociated pathway, which was indicated by the increased expression of cleavedcaspase3, cleavedcaspase9, apoptotic protease activating factor1, cleavedpoly (ADPribose) polymerase 1 and the elevation of B cell lymphoma2 (Bcl2) associated X protein/Bcl2 ratio associated with apoptosis. Therefore, UDCA may be a potential drug for the treatment of human melanoma.
Sujet(s)
Apoptose/effets des médicaments et des substances chimiques , Mitochondries/effets des médicaments et des substances chimiques , Acide ursodésoxycholique/pharmacologie , Chlorométhyl cétones d'acides aminés/pharmacologie , Inhibiteurs des caspases/pharmacologie , Caspases/métabolisme , Lignée cellulaire tumorale , Tests de criblage d'agents antitumoraux , Points de contrôle de la phase G2 du cycle cellulaire/effets des médicaments et des substances chimiques , Humains , Mélanome/traitement médicamenteux , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Microscopie électronique à transmission , Mitochondries/métabolisme , Mitochondries/ultrastructure , Espèces réactives de l'oxygène/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Tumeurs cutanées/traitement médicamenteux , Acide ursodésoxycholique/usage thérapeutiqueRÉSUMÉ
MicroRNAs (miRNA) play important roles in the initiation and progression of breast cancer. Here, we investigated the role of miR-601 in breast cancer and found that its expression was significantly down-regulated in breast cancer tissues compared with matched adjacent non-cancerous breast tissues. Moreover, we found that down-regulation of miR-601 was closely associated with distant metastasis and poor distant metastasis-free survival in breast cancer. In addition, miR-601 levels were inversely correlated with metastatic potential of human breast cancer cell lines. Further experiments showed that ectopic overexpression of miR-601 suppressed breast cancer cell proliferation, migration and invasion, whereas miR-601 knockdown promoted breast cancer cell proliferation, migration and invasion. Furthermore, protein tyrosine phosphatase type IVA 1 (PTP4A1) was identified as a direct target of miR-601. Overexpression of miR-601 repressed PTP4A1 mRNA and protein expression. Conversely, inhibition of miR-601 increased PTP4A1 mRNA and protein expression. Taken together, our data suggest that miR-601 inhibits growth and invasion of breast cancer cells by targeting PTP4A1 and that miR-601 is a potential biomarker for prognosis and therapeutic target in breast cancer.
Sujet(s)
Marqueurs biologiques tumoraux/métabolisme , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Protéines du cycle cellulaire/métabolisme , Protéines membranaires/métabolisme , microARN/métabolisme , Protein Tyrosine Phosphatases/métabolisme , Séquence nucléotidique , Lignée cellulaire tumorale , Mouvement cellulaire , Prolifération cellulaire , Survie sans rechute , Régulation négative , Femelle , Humains , microARN/génétique , Invasion tumorale , Pronostic , Test clonogénique de cellules souches tumoralesRÉSUMÉ
Some microRNAs (miRNAs) have been implicated in hepatocellular carcinoma (HCC) development and progression. However, the roles and mechanisms of several miRNAs in HCC remain poorly understood. Here, we report that miR-379-5p, which is down-regulated in HCC tissues and cell lines, is associated with advanced TNM stage and metastasis in HCC. The ectopic overexpression of miR-379-5p inhibited HCC cell migration, invasion, epithelial-to-mesenchymal transition (EMT) and metastasis both in vitro and in vivo. Conversely, miR-379 knockdown increased migration, invasion and EMT in HCC cells. Moreover, miR-379-5p exerted this function by directly targeting focal adhesion kinase (FAK) 3'-UTR and repressing FAK expression, thus leading to suppression of AKT signaling. Furthermore, the tumor suppressive effects of miR-379-5p in HCC cells were reversed by activating AKT signaling or restoring FAK expression. In clinical samples of HCC, miR-379-5p negatively correlated with FAK, which was up-regulated in HCC. Taken together, our findings highlight the important role of miR-379-5p in regulating the EMT and metastasis of HCC by targeting FAK/AKT signaling, suggesting that miR-379-5p may represent a novel potential therapeutic target and prognostic marker for HCC.
Sujet(s)
Carcinome hépatocellulaire/métabolisme , Focal adhesion kinase 1/métabolisme , Tumeurs du foie/métabolisme , microARN/physiologie , Protéines proto-oncogènes c-akt/métabolisme , Régions 3' non traduites , Animaux , Séquence nucléotidique , Sites de fixation , Carcinome hépatocellulaire/secondaire , Lignée cellulaire tumorale , Mouvement cellulaire , Transition épithélio-mésenchymateuse , Régulation de l'expression des gènes tumoraux , Humains , Tumeurs du foie/anatomopathologie , Souris de lignée BALB C , Souris nude , Invasion tumorale , Transplantation tumorale , Interférence par ARNRÉSUMÉ
AIM: The present case-control study was conducted to explore the association of MTHFR gene polymorphism and relations of P16, MGMT and HMLH1 to MTHFR and folate intake. METHODS: A total of 257 cases of esophageal squamous cell carcinoma confirmed by histopathological examination were collected. Genotyping of P16, MGMT and HMLH1 was accomplished by methylation-specific polymerase chain reaction (PCR) after sodium bisulfate modification of DNA and the MTHFR C677T genetic polymorphism was detected by PCR- restriction fragment-length polymorphism (PCR-RFLP). RESULTS: The proportions of DNA hypermethylation in P16, MGMT and hMLH1 in cancer tissues were significantly higher than in paracancerous normal tissue. The proportion of hypermethylation in at least one gene was 88.5% in cancer tissue, and was also significantly higher than that in paracancerous normal tissue. Our finding showed individuals with homozygotes (TT) of MTHFR C677T had significant risk of DNA hypermethylation of MGMT in cancer tissues, with an OR (95% CI) of 3.15 (1.12-6.87). Similarly, patients with high intake of folate also showed a slight high risk of DNA methylation of MGMT, with OR (95% CI) of 2.03 (1.05-4.57). CONCLUSION: Our study found the P16, MGMT and hMLH1 demonstrate a high proportion of hypermethylation in esophageal squamous cell cancer cancer tissues, which might be used as biomarkers for cancer detection.
Sujet(s)
Protéines adaptatrices de la transduction du signal/génétique , Carcinome épidermoïde/génétique , Méthylation de l'ADN , DNA modification methylases/génétique , Enzymes de réparation de l'ADN/génétique , Tumeurs de l'oesophage/génétique , Acide folique/métabolisme , Methylenetetrahydrofolate reductase (NADPH2)/génétique , Protéines tumorales/génétique , Protéines nucléaires/génétique , Polymorphisme génétique/génétique , Protéines suppresseurs de tumeurs/génétique , Études cas-témoins , Inhibiteur p16 de kinase cycline-dépendante , ADN/génétique , Femelle , Génotype , Humains , Mâle , Adulte d'âge moyen , Protéine-1 homologue de MutL , Stadification tumorale , Réaction de polymérisation en chaîne , Polymorphisme de restriction , Pronostic , Facteurs de risqueRÉSUMÉ
AIM: To evaluate the association of glutathione S-transferases gene polymorphisms with the risk of gastric cancer, with reference to smoking and Helicobacter pylori infection. METHODS: We conducted a 1:1 matched case-control study with 410 gastric cancer cases and 410 cancer-free controls. Polymorphisms of GSTM1, GSTT1 and GSTP1 were determined using PCR-CTPP. RESULTS: The GSTM1 and GSTT1 null genotypes were significantly associated with the risk of gastric cancer after adjusting for potential confounding factors (OR=1.68, 95% CI=1.32-2.23 for null GSTM1, OR=1.73; 95% CI=1.24-2.13 for null GSTT1). The combination of null GSTM1 and null GSTT1 conferred an elevated risk (OR=2.54, 95% CI=1.55-3.39). However, no association was found for GSTP1 polymorphism The smoking modified the association of GSTM1 and GSTT1 null genotypes with the risk of gastric cancer. CONCLUSION: GSTM1 and GSTT1 null genotypes are associated with increased risk of gastric cancer, and smoking modifies the association.
Sujet(s)
Glutathione transferase/génétique , Infections à Helicobacter/génétique , Helicobacter pylori/isolement et purification , Fumer/génétique , Tumeurs de l'estomac/génétique , Tumeurs de l'estomac/microbiologie , Sujet âgé , Études cas-témoins , Femelle , Prédisposition génétique à une maladie , Génotype , Glutathione S-transferase pi/génétique , Infections à Helicobacter/complications , Infections à Helicobacter/enzymologie , Humains , Mâle , Polymorphisme génétique , Risque , Fumer/effets indésirables , Tumeurs de l'estomac/enzymologieRÉSUMÉ
BACKGROUND AND AIMS: The effects of polymorphism of NAD(P)H quinone oxidoreductase 1 (NQO1 Pro187Ser, rs1800566) on the risks of colorectal adenoma and cancer have been widely studied and results remain controversial. Therefore, the aim of this meta-analysis was to quantitatively assess the relationships. METHODS: Databases of Medline, Embase and Wanfang were retrieved until May 15, 2011. Pooled odds ratio (OR) and 95% confidence interval (95% CI) as effect sizes were calculated by using fixed- or random-effect model. Cochrane Q-test was used to explore between-study heterogeneity; p <0.10 indicated statistical significance. RESULTS: A total of 12 case-control studies with 11,700 individuals (including 5528 cases and 6172 controls) were included in this meta-analysis. Of these studies, four studies conducted in Caucasian populations were for colorectal adenoma, and eight studies were for colorectal cancer. NQO1 187Ser allele was significantly associated with increased risk of colorectal adenoma in co-dominant and dominant comparison models (OR = 1.07, 95% CI = 1.04-1.32 for ProSer vs. ProPro and OR = 1.19, 95% CI = 1.06-1.33 for Ser carries vs. ProPro), without between-study heterogeneity. Overall, NQO1 Pro187Ser was not associated with risk of colorectal cancer, without between-study heterogeneity. Subgroup analyses indicated that Ser allele was significantly associated with increased risk of colorectal cancer for Caucasians (OR = 1.14, 95% CI = 1.00-1.30 for ProSer vs. ProPro and OR = 1.16, 95% CI = 1.02-1.31 for Ser carries vs. ProPro). CONCLUSIONS: This meta-analysis suggested that Ser allele of NQO1 Pro187Ser significantly contributed to the increased risks of colorectal adenoma and cancer in Caucasians.
Sujet(s)
Adénomes/génétique , Tumeurs colorectales/génétique , Mutation faux-sens , NADPH dehydrogenase (quinone)/génétique , Polymorphisme de nucléotide simple , , Adénomes/enzymologie , Adénomes/ethnologie , Études cas-témoins , Tumeurs colorectales/enzymologie , Tumeurs colorectales/ethnologie , Études d'associations génétiques , Humains , Modèles linéaires , Odds ratio , Facteurs de risqueRÉSUMÉ
AIM: To explore the effect of protein metabolism and immunologic function of glutamine after operation in elder gastrointestinal tumor. METHODS: Form march 2007 to 2010, 87 cases of elder gastrointestinal tumor were given parenteral nutrition and glutamine 0.6 g/( Kg x d).The period of treatment were 8 days. IgA, IgG, IgM were CD4, measured by single immunodiffusion, CD3(+), CD4(+), CD8(+), CD4(+) /CD8(+) were measured by immunohistochemical method, and the index(Alb, PAB, TF, nitrogen equilibrium) were monitored the proteid catabolism distribution. RESULTS: After the treatment, CD3(+), CD4(+), CD8(+), CD4(+)/CD8(+), IgG, IgA, IgM were evidently declined( P <0.05). Alb, PAB, TF were evidently declined in 4 days postoperatively (P < 0.05), the restore were more obvious in 8 days postoperatively (P < 0. 05). Nitrogen equilibrium was worse in the early postoperative and the restore were more obvious in 8 days postoperatively (P < 0.05). CONCLUSION: Glutamine can improve patient's nutrition, enhance their immunologic function.
Sujet(s)
Lymphocytes T CD4+/métabolisme , Tumeurs gastro-intestinales/traitement médicamenteux , Tumeurs gastro-intestinales/chirurgie , Glutamine/administration et posologie , Immunoglobuline A/métabolisme , Immunoglobuline G/métabolisme , Immunoglobuline M/métabolisme , Sujet âgé , Rapport CD4-CD8 , Lymphocytes T CD8+/métabolisme , Traitement médicamenteux adjuvant , Femelle , Tumeurs gastro-intestinales/immunologie , Humains , Numération des lymphocytes , Mâle , Adulte d'âge moyen , Nutrition parentérale , Période postopératoire , Sérumalbumine/métabolismeRÉSUMÉ
By means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-particle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the composition, morphology, particle size and zeta potential of urinary microcrystalline in urine of magnesium ammonium phosphate stone formers were investigated. The components of stones were also analyzed. The results showed that there was a close relationship among stone components, urinary microcrystalline composition and urine pH. A high pH value of 6.5 or more usually appeared in the urine of magnesium ammonium phosphate stone formers. The main component of urine microcrystalline was magnesium ammonium phosphate crystals with different crystal water such as monohydrate or hexahydrate. Magnesium ammonium phosphate crystals are mainly petal-shaped, crosswise shape. These microcrystalline have an uneven particle size distribution, a wider distribution range, and apparent aggregation. There is no significant difference in the zeta potential between the magnesium ammonium phosphate stone formers (mean (-9.83 +/- 0.66) mV) and healthy control subjects (mean (-10.74 +/- 0.25) mV). This study can help predict the occurrence of urolithiasis, and provide inspiration to the prediction of the type of urinary stones.
Sujet(s)
Composés du magnésium/composition chimique , Phosphates/composition chimique , Calculs urinaires/composition chimique , Humains , Concentration en ions d'hydrogène , Microscopie électronique à balayage , Microscopie électronique à transmission , Spectroscopie infrarouge à transformée de Fourier , Struvite , Calculs urinaires/urine , Diffraction des rayons XRÉSUMÉ
The difference of urine crystallites under 1000 nm in 10 patients with urolithiasis and 10 healthy subjects with no history of urolithiasis was comparatively studied with the nanoparticle size analyzer. By comparing the differences of intensity-autocorrelation curve, polydispersity index (PDI), Zeta potential, and relative error of average diameter of the two kinds of urine crystallites, it was concluded that the urine crystallites of healthy subjects were more stable than those of patients. The urine crystallites of healthy subjects had a narrower size distribution from 100 nm to 350 nm and a better dispersion (PDI < 0.3). However, the urine crystallites of patients with urolithiasis had a wider distribution from dozens of nanometers to 1000 nm and a worse dispersion (PDI > 0.5). The best processing method for urine crystallites detection was found: after antisepticising and protein-coagulating with formaldehyde, the urine was diluted with distilled water of the same volume, then filtrated through a micropore film of 3 microm, and the filtrate was centrifugalized at 4000 rpm for 15 minutes. This method can remove the cell fragments and macromolecular substances in the urine without affecting the detection of the urine crystallites under 1000 nm. The results were consistent with those obtained by transmission electron microscope (TEM).
Sujet(s)
Nanoparticules/composition chimique , Calculs urinaires/composition chimique , Centrifugation , Éthanol/composition chimique , Filtration , Formaldéhyde/composition chimique , Humains , Microscopie électronique à transmission , Nanoparticules/ultrastructure , Taille de particule , Porosité , Protéinurie/urine , Calculs urinaires/ultrastructure , Urolithiase/urine , Diffraction des rayons XRÉSUMÉ
The components, zeta potential, morphology of nanocrystallites in urines of 10 uric acid stone formers as well as their relationship with the formation of uric acid stones were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nanoparticle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The urine pH of uric acid stone formers was relatively low within the range of 4.8 to 5.7. The main constituent of urinary crystallites was uric acid. Their particle size distribution was highly uneven, ranging from several nanometers to several tens of micrometers, and obvious aggregation was observed. The zeta potential of urinary crystallites in ten lithogenic patients was -6.02 mV, which was higher than that in ten normal subjects (-10.1 mV). After drug therapies (potassium citrate was taken), the urine pH value of the uric acid stone formers increased to 6.5 or so, and at this pH value most of the uric acid had changed to urate. Since the solubility of urate increased greatly than uric acid, the risk of the formation of uric acid stone reduced. The results in this paper showed that there was a close relationship among stone components, urinary crystallites composition and urine pH.
Sujet(s)
Spectroscopie infrarouge à transformée de Fourier , Acide urique/composition chimique , Calculs urinaires/composition chimique , Humains , Microscopie électronique à balayage , Microscopie électronique à transmission , Nanoparticules , Taille de particule , Diffraction des rayons XRÉSUMÉ
The crystallites in urine are related closely with the formation of urolithiasis. In the present paper the composition, morphology and Zeta potential of crystallites of twenty calcium oxalate stone formers were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nanoparticle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that calcium oxalate calculi usually coexisted with a little of uric acid, calcium phosphate, and magnesium ammonium phosphate. By contrast, the compositions of urine crystallites of the patients with calcium oxalate calculi were mainly uric acid, phosphate, calcium oxalate and so on. Most of them had sharp angularity with a particle size distribution ranging from tens of nanometers to tens of microns; and obvious aggregation was observed. The negative value of Zeta potential of urine crystallites in the twenty stone formers (average value -5.92 mV) was less than that in the twenty normal subjects (-12.9 mV). However, there was no obvious difference in the urine pH between stone formers (average pH 6.03) and normal subjects (average pH 5.92). The study on the relationship between urine crystallites and urinary calculi components will be helpful for finding out the causes of urolithiasis and providing an important basis for the scientific prevention methods and reasonable treatments in clinic.