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1.
World J Gastroenterol ; 13(47): 6385-95, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18081228

RESUMO

AIM: To characterize the correlation between severity of hepatopulmonary syndrome (HPS) and degree of hepatic dysfunction, and to explore how intestinal endotoxemia (IETM) affects the development of HPS in cirrhotic rats. METHODS: Male Wister rats were fed with a diet containing maize flour, lard, cholesterol, and alcohol and injected subcutaneously with CCl(4) oil solution every two days for 8 wk to induce typical cirrhosis and development of HPS. The animals were also given a nitric oxide (NO) production inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME) intraperitoneally, and an iNOS inhibitor, aminoguanidine hydrochloride (AG) via gavage daily from the end of the 4th wk to the end of the 6th or 8th wk, or a HO-1 inhibitor, zinc protoporphyrin (ZnPP) intraperitoneally 12 h prior to killing. Blood, liver and lung tissues were sampled. RESULTS: Histological deterioration of the lung paralleled to that of the liver in the cirrhotic rats. The number of pulmonary capillaries was progressively increased from 6.1 +/- 1.1 (count/filed) at the 4th wk to 14.5 +/- 2.4 (count/filed) at the 8th wk in the cirrhotic rats. Increased pulmonary capillaries were associated with increased blood levels of lipopolysaccharide (LPS) (0.31 +/- 0.08 EU/mL vs control 0.09 +/- 0.03 EU/mL), alanine transferase (ALT, 219.1 +/- 17.4 U/L vs control 5.9 +/- 2.2 U/L) and portal vein pressure. Compared with normal control animals, the number of total cells in bronchoalveolar lavage fluid (BALF) of the cirrhotic rats at the 8th wk was not changed, but the number of macrophages and the ratio of macrophages to total cells were increased by nearly 2-fold, protein expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) started to increase significantly at the 4th wk, and reached its peak at the 8th wk in the lung of cirrhotic rats. The increase of iNOS expression appeared to be quicker than that of eNOS. NO(2)(-)/NO(3)(-) was also increased, which was correlated to the increase of iNOS (r = 0.7699, P < 0.0001) and eNOS (r = 0.5829, P < 0.002). mRNA expression of eNOS and iNOS was highly consistent with their protein expression. CONCLUSION: Progression and severity of HPS as indicated by both increased pulmonary capillaries and histological changes are closely associated with LPS levels and progression of hepatic dysfunction as indicated by increased levels of ALT and portal vein pressure. Intestinal endotoxemia plays a central role in the development of HPS in the cirrhotic rat model by inducing NO and/or CO.


Assuntos
Endotoxemia/complicações , Síndrome Hepatopulmonar/etiologia , Enteropatias/complicações , Cirrose Hepática Experimental/complicações , Fígado/patologia , Pulmão/patologia , Alanina Transaminase/sangue , Animais , Líquido da Lavagem Broncoalveolar/citologia , Capilares/patologia , Carboxihemoglobina/metabolismo , Citocinas/sangue , Progressão da Doença , Endotoxemia/metabolismo , Endotoxemia/patologia , Endotoxemia/fisiopatologia , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Heme Oxigenase (Desciclizante)/metabolismo , Síndrome Hepatopulmonar/metabolismo , Síndrome Hepatopulmonar/patologia , Síndrome Hepatopulmonar/fisiopatologia , Enteropatias/metabolismo , Enteropatias/patologia , Enteropatias/fisiopatologia , Lipopolissacarídeos/sangue , Fígado/enzimologia , Fígado/fisiopatologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Pulmão/fisiopatologia , Masculino , Malondialdeído/sangue , NG-Nitroarginina Metil Éster/farmacologia , Neovascularização Patológica/etiologia , Neovascularização Patológica/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III , Pressão na Veia Porta , Protoporfirinas/farmacologia , Ratos , Ratos Wistar , Índice de Gravidade de Doença , Fatores de Tempo , Regulação para Cima
2.
World J Gastroenterol ; 13(25): 3500-7, 2007 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-17659698

RESUMO

AIM: To develop and characterize a practical model of Hepatopulmonary syndrome (HPS) in rats. METHODS: The experimental animals were randomized into five feeding groups: (1) control (fed standard diet), (2) control plus intraperitoneal injection with lipopolysaccharide (LPS), (3) cirrhosis (fed a diet of maize flour, lard, cholesterol, and alcohol plus subcutaneously injection with carbon tetrachloride (CCl(4)) oil solution), (4) cirrhosis plus LPS, and (5) cirrhosis plus glycine and LPS. The blood, liver and lung tissues of rats were sampled for analysis and characterization. Technetium 99m-labeled macroaggregated albumin (Tc99m-MAA) was used to test the dilatation of pulmonary microvasculature. RESULTS: Typical cirrhosis and subsequent hepato-pulmonary syndrome was observed in the cirrhosis groups after an 8 wk feeding period. In rats with cirrhosis, there were a decreased PaO(2) and PaCO(2) in arterial blood, markedly decreased arterial O(2) content, a significantly increased alveolar to arterial oxygen gradient, an increased number of bacterial translocated within mesenteric lymph node, a significant higher level of LPS and tumor necrosis factor-alpha (TNF-alpha) in plasma, and a significant greater ratio of Tc99m-MAA brain-over-lung radioactivity. After LPS administration in rats with cirrhosis, various pathological parameters got worse and pulmonary edema formed. The predisposition of glycine antagonized the effects of LPS and significantly alleviated various pathological alterations. CONCLUSION: The results suggest that: (1) a characteristic rat model of HPS can be non-invasively induced by multiple pathogenic factors including high fat diet, alcohol, cholesterol and CCl(4); (2) this model can be used for study of hepatopulmonary syndrome and is clinically relevant; and (3) intestinal endotoxemia (IETM) and its accompanying cytokines, such as TNF-alpha, exert a crucial role in the pathogenesis of HPS in this model.


Assuntos
Endotoxemia/complicações , Síndrome Hepatopulmonar/etiologia , Cirrose Hepática Experimental/complicações , Animais , Translocação Bacteriana , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Pulmão/patologia , Masculino , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/sangue
3.
Zhonghua Gan Zang Bing Za Zhi ; 15(9): 676-80, 2007 Sep.
Artigo em Zh | MEDLINE | ID: mdl-17903370

RESUMO

OBJECTIVE: To investigate HMGB-1 expression and its extracellular release of cultured primary hepatic parenchymal cells (HC) and Kupffer cells (KC) that were induced by lipopolysaccharides (LPS). METHODS: Primary hepatic parenchymal cells and Kupffer cells were cultured in flasks, and some cells were treated with 500 microg/L LPS for 24 hours (induced group) and some were not treated with LPS and served as controls. All of the cells were repeatedly frozen-thawed, and the expression levels of HMGB1-mRNA and HMGB1 proteins were detected by semi-quantitative RT-PCR and Western blot respectively. Then HC and KC were subcultured in 24-well culture plates for 6 h, 12 h, 24 h and 48 h, and the HMGB1 protein in culture fluids was detected by Western blot at each time point. RESULTS: Compared with the cells in the control group, the expression levels of HMGB1-mRNA in the induced group were significantly increased in both HC and KC at 24 h (t=31.32 and 45.90, P<0.05) and the protein levels of HMGB1 showed the same results (t=46.19 and 38.44, P<0.05). There was a small quantity of HMGB1 protein in the culture fluids of two control groups and the induced group of HC. However the HMGB1 protein in the induced group of KC were obviously increased with prolonged culture time (F=42.74, P<0.05). Compared with the control group, the level of HMGB1 protein in the induced group of KC was not increased at 6 h (t=9.57, P>0.05) but was significantly increased at 12 h, 24 h and 48 h (t=21.95, 32.39, 44.16, respectively P<0.05). CONCLUSION: LPS could increase HMGB1 expression of HC and KC and HMGB1 release from KC, but not from HC. The results suggest that KC play an important role in triggering inflammation and liver injury.


Assuntos
Proteína HMGB1/metabolismo , Hepatócitos/metabolismo , Células de Kupffer/metabolismo , Animais , Células Cultivadas , Feminino , Lipopolissacarídeos , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , RNA Mensageiro/genética , Ratos , Ratos Wistar
4.
Medicine (Baltimore) ; 96(48): e8948, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29310392

RESUMO

RATIONALE: Hemangiomas are benign tumors characterized by an abnormal proliferation of blood vessels, most often occur in the skin and subcutaneous tissue, intramuscular hemangioma, a distinctive type of hemangioma within the skeletal muscle, account for <1% of all hemangiomas, temporalis muscle is a very uncommon site, cavernous hemangioma of the temporalis muscle with prominent formation of phleboliths is rare reported. PATIENT CONCERNS: A 62-year-old man presented with a slowly increased mass in his right temporal fossa. DIAGNOSES: Computed tomography (CT) scan showed the lesion across the zygomatic arch, with many calcified nodules differ in sizes and no erosion to the bone, magnetic resonance imaging (MRI) showed an oval lesion with hypointense and isointense on T2-weighted imaging within the temporal muscle, and preoperation diagnosis was hemangioma. INTERVENTIONS: The tumor was resected under general anesthesia. OUTCOMES: The mass was excised completely, and the histopathology examination confirmed the diagnosis of cavernous hemangioma with prominent formation of phleboliths. The patient recovered very well without dysfunctions. LESSONS: Cavernous hemangioma should be suspected when mass occurs in this region. CT and MRI are important for the early diagnosis of tumor, and resection the tumor completely is recommended.


Assuntos
Hemangioma Cavernoso/complicações , Neoplasias Musculares/complicações , Calcificação Vascular/complicações , Diagnóstico Diferencial , Hemangioma Cavernoso/diagnóstico por imagem , Hemangioma Cavernoso/patologia , Hemangioma Cavernoso/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Musculares/diagnóstico por imagem , Neoplasias Musculares/patologia , Neoplasias Musculares/cirurgia , Músculo Temporal/diagnóstico por imagem , Músculo Temporal/patologia , Músculo Temporal/cirurgia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/patologia , Calcificação Vascular/cirurgia
5.
World J Gastroenterol ; 12(37): 6046-9, 2006 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-17009407

RESUMO

AIM: To observe the inhibition of hepatitis B virus replication and expression by transfecting vector-based small interference RNA (siRNA) pGenesil-HBV X targeting HBV X gene region into HepG2.2.15 cells. METHODS: pGenesil-HBV X was constructed and transfected into HepG2.2.15 cells via lipofection. HBV antigen secretion was determined 24, 48, and 72 h after transfection by time-resolved immunofluorometric assays (TRFIA). HBV replication was examined by fluorescence quantitative PCR, and the expression of cytoplasmic viral proteins was determined by immunohistochemistry. RESULTS: The secretion of HBsAg and HBeAg into the supernatant was found to be inhibited by 28.5% and 32.2% (P < 0.01), and by 38.67% (P < 0.05) and 42.86% (P < 0.01) at 48 h and 72 h after pGenesil-HBV X transfection, respectively. Immunohistochemical staining for cytoplasmic HBsAg showed a similar decline in HepG2.2.15 cells 48 h after transfection. The number of HBV genomes within culture supernatants was also significantly decreased 48 h and 72 h post-transfection as quantified by fluorescence PCR (P < 0.05). CONCLUSION: In HepG2.2.15 cells, HBV replication and expression is inhibited by vector-based siRNA pGenesil-HBV X targeting the HBV X coding region.


Assuntos
Replicação do DNA/genética , Vírus da Hepatite B/genética , Hepatoblastoma/genética , Neoplasias Hepáticas/genética , Interferência de RNA/fisiologia , Transativadores/metabolismo , Linhagem Celular Tumoral , Replicação do DNA/fisiologia , DNA Viral/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Regulação Viral da Expressão Gênica/genética , Regulação Viral da Expressão Gênica/fisiologia , Vetores Genéticos , Antígenos da Hepatite B/genética , Antígenos da Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/metabolismo , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Plasmídeos/genética , RNA Interferente Pequeno/genética , RNA Viral/genética , Transativadores/genética , Transfecção , Proteínas Virais Reguladoras e Acessórias
6.
World J Gastroenterol ; 22(10): 2949-59, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26973391

RESUMO

AIM: To evaluate the effect of artesunate (AS) supplementation on bacterial translocation (BT) and gut microbiota in a rat model of liver cirrhosis. METHODS: Fifty-four male Sprague-Dawley rats were randomly divided into a normal control group (N), a liver cirrhosis group (M) and a liver cirrhosis group intervened with AS (MA). Each group was sampled at 4, 6 and 8 wk. Liver cirrhosis was induced by injection of carbon tetrachloride (CCl4), intragastric administration of 10% ethanol, and feeding a high fat diet. Rats in the MA group were intragastrically administered with AS (25 mg/kg body weight, once daily). Injuries of the liver and intestinal mucosa were assessed by hematoxylin-eosin or Masson's trichrome staining. Liver index was calculated as a ratio of the organ weight (g) to body weight (g). The gut microbiota was examined by automated ribosomal intergenic-spacer analysis of fecal DNA. BT was assessed by standard microbiological techniques in the blood, mesenteric lymph nodes (MLNs), liver, spleen, and kidney. RESULTS: Compared to group N, the body weight was reduced significantly in groups M and MA due to the development of liver cirrhosis over the period of 8 wk. The body weight was higher in group MA than in group M. The liver indices were significantly elevated at 4, 6 and 8 wk in groups M and MA compared to group N. AS supplementation partially decreased the liver indices in group MA. Marked histopathologic changes in the liver and small intestinal mucosa in group M were observed, which were alleviated in group MA. Levels of pro-inflammatory interleukin-6 and tumor necrosis factor-α were significantly elevated at 8 wk in ileal homogenates in group M compared to group N, which were decreased after AS supplementation in group MA. The dysbiosis of gut microbiota indicated by the mean diversity (Shannon index) and mean similarity (Sorenson index) was severe as the liver cirrhosis developed, and AS supplementation had an apparent intervention effect on the dysbiosis of gut microbiota at 4 wk. The occurrence of BT was increased in the liver of group M compared to that of group N. AS supplementation reduced BT in group MA at 8 wk. BT also occurred in the MLNs, spleen, and kidney, which was reduced by AS supplementation. BT was not detected in the blood in any group. CONCLUSION: Dysbiosis of gut microbiota, injury of intestinal mucosal barrier and BT occurred as liver cirrhosis progressed, which might enhance inflammation and aggravate liver injury. AS may have other non-antimalarial effects that modulate gut microbiota, inhibit BT and alleviate inflammation, resulting in a reduction in CCl4, alcohol and high fat-caused damages to the liver and intestine.


Assuntos
Anti-Inflamatórios/farmacologia , Artemisininas/farmacologia , Bactérias/efeitos dos fármacos , Translocação Bacteriana/efeitos dos fármacos , Disbiose , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Cirrose Hepática Experimental/tratamento farmacológico , Animais , Artesunato , Bactérias/imunologia , Bactérias/metabolismo , Tetracloreto de Carbono , Citocinas/imunologia , Citocinas/metabolismo , Progressão da Doença , Fezes/microbiologia , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Intestinos/microbiologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/imunologia , Cirrose Hepática Experimental/microbiologia , Masculino , Ratos Sprague-Dawley , Fatores de Tempo
7.
Zhonghua Gan Zang Bing Za Zhi ; 11(10): 592-4, 2003 Oct.
Artigo em Zh | MEDLINE | ID: mdl-14572333

RESUMO

OBJECTIVES: To develop a new method for amplifying and sequencing the full-length of HBV genome. METHODS: A pair of primers located at the nick region of HBV molecule and a thermostable polymerase with high fidelity and sensitivity were used. After cloning the PCR products into a plasmid, the sequences of HBV genome were analyzed. RESULTS: The full-length of HBV genome were acquired using this method. The sensitivity and fidelity of the new method were also analyzed. The least quantity of initial templates was 10(2) and the artificial mutation rate was 1.2 bp/kb. CONCLUSION: This method can be used in amplification and sequence analysis of the full-length of HBV genome on a large scale.


Assuntos
Genoma Viral , Vírus da Hepatite B/genética , Mutação Puntual , Primers do DNA/genética , Amplificação de Genes , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Vírion/genética , Vírion/imunologia , Vírion/isolamento & purificação
8.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 30(3): 199-203, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-25244780

RESUMO

OBJECTIVE: To explore the mechanism of tanshinol on alleviate the inflammatory injury of lung tissue in rat hepatopulmonary syndrome (HPS). METHODS: SD rats were randomly divided into normal control group (n = 8), hepatopulmonary syndrome (HPS) group (n = 11) and tanshinol intervention group (n = 9). HE staining was used to observe the histopathology changes of pulmonary and hepatic tissues, and to count the number of macrophages in lung tissues. The activity of alanine transferase (ALT) and concentrations of endotoxin, tumor necrosis factor-a (TNF-alpha) and homocystein (Hcy) in plasma were detected. The concentrations of TNF-alpha, nitric oxide (NO) and malondialdehyde (MDA) and the activity of inducible nitric oxide synthase (iNOS) in the lung tissues were measured, respectively. RESULTS: Thickened alveolar septum and increased macrophages were observed in lungs in HPS rat. After administered with tanshinol, the pulmonary pathological changes were alleviated and the number of macrophages in lung tissue was decreased compared with HPS group. The activity of ALT and the concentrations of endotoxin, TNF-alpha and Hcy in plasma ,and TNF-alpha, iNOS, NO and MDA in lung tissue in HPS group were higher than those of normal control group; meanwhile, those tanshinol group were less those that of HPS group. CONCLUSION: Tanshinol may play an important role in delaying the development of HPS through protecting liver or directly antagonizing the effect of intestinal endotoxemia so as to alleviate the inflammatory reaction in lung tissue.


Assuntos
Ácidos Cafeicos/farmacologia , Síndrome Hepatopulmonar/tratamento farmacológico , Alanina Transaminase/metabolismo , Animais , Modelos Animais de Doenças , Endotoxinas/sangue , Síndrome Hepatopulmonar/patologia , Homocisteína/sangue , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
10.
World J Gastroenterol ; 18(14): 1680-8, 2012 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-22529699

RESUMO

AIM: To investigate the effects of heme oxygenase (HO)-1 on liver fibrosis and the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and nuclear factor-kappa B (NF-κB) in rats. METHODS: Sixty Wistar rats were used to construct liver fibrosis models and were randomly divided into 5 groups: group A (normal, untreated), group B (model for 4 wk, untreated), group C (model for 6 wk, untreated), group D [model for 6 wk, treated with zinc protoporphyrin IX (ZnPP-IX) from week 4 to week 6], group E (model for 6 wk, treated with hemin from week 4 to week 6). Next, liver injury was assessed by measuring serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and albumin levels. The degree of hepatic fibrosis was evaluated by measuring serum hyaluronate acid (HA), type IV collagen (IV-C) and by histological examination. Hydroxyproline (Hyp) content in the liver homogenate was determined. The expression levels of alpha-smooth muscle actin (α-SMA) in liver tissue were measured by real-time quantitative polymerase chain reaction (RT-PCR). The expression levels of PPARγ and NF-κB were determined by RT-PCR and Western blotting. RESULTS: The expression of HO-1 increased with the development of fibrosis. Induction of HO-1 by hemin significantly attenuated the severity of liver injury and the levels of liver fibrosis as compared with inhibition of HO-1 by ZnPP-IX. The concentrations of serum ALT, AST, HA and IV-C in group E decreased compared with group C and group D (P < 0.01). Amount of Hyp and α-SMA in the liver tissues in group E decreased compared with group C (0.62 ± 0.14 vs 0.84 ± 0.07, 1.42 ± 0.17 vs 1.84 ± 0.17, respectively, P < 0.01) and group D (0.62 ± 0.14 vs 1.11 ± 0.16, 1.42 ± 0.17 vs 2.56 ± 0.37, respectively, P < 0.01). The expression of PPARγ at levels of transcription and translation decreased with the development of fibrosis especially in group D; and it increased in group E compared with groups C and D (0.88 ± 0.15 vs 0.56 ± 0.19, 0.88 ± 0.15 vs 0.41 ± 0.11, respectively, P < 0.01). The expression of NF-κB increased with the development of fibrosis especially in group D; and it decreased in group E compared with groups C and D (1.43 ± 0.31 vs 1.89 ± 0.29, 1.43 ± 0.31 vs 2.53 ± 0.54, respectively, P < 0.01). CONCLUSION: Our data demonstrate a potential mechanism that HO-1 can prevent liver fibrosis by enhancing the expression of PPARγ and decreasing the expression of NF-κB in liver tissues.


Assuntos
Heme Oxigenase (Desciclizante)/fisiologia , Cirrose Hepática/metabolismo , Fígado/patologia , NF-kappa B/metabolismo , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Animais , Heme Oxigenase (Desciclizante)/efeitos dos fármacos , Hemina/farmacologia , Fígado/efeitos dos fármacos , Masculino , Protoporfirinas/farmacologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
13.
J Colloid Interface Sci ; 345(2): 168-73, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20202642

RESUMO

CaCO(3) nanoparticles were coated with stearate through a salt-exchange procedure. Their coverage had been successfully controlled by extraction in a Soxhlet apparatus, based on which a series of CaCO(3) nanoparticles were obtained with different surface coverages. They were characterized with thermogravimetric analysis, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. It was found that free stearate, intercalated stearate and chemically-bonded alkyl chains could be extracted sequentially with the Soxhlet apparatus. Thus, the coverages of CaCO(3) nanoparticles could be adjusted through carefully extracting the stearates from the CaCO(3) nanoparticles with multi-layer coverage. Spectroscopic results revealed that the alkyl chains tended to adopt an extended-chain conformation in the monolayer coverage as well as the bi-layer coverage, but less ordered conformation in partially-coated coverage and random orientation at the outmost surface of the coated nanoparticles.

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