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1.
Br Poult Sci ; 64(4): 467-475, 2023 Aug.
Article En | MEDLINE | ID: mdl-36939295

1. The H9N2 subtype avian influenza virus can infect both chickens and humans. Previous studies have reported a role for erythrocytes in immunity. However, the role of H9N2 against chicken erythrocytes and the presence of complement-related genes in erythrocytes has not been studied. This research investigated the effect of H9N2 on complement-associated gene expression in chicken erythrocytes.2. The expression of complement-associated genes (C1s, C1q, C2, C3, C3ar1, C4, C4a, C5, C5ar1, C7, CD93 and CFD) was detected by reverse transcription-polymerase chain reaction (RT-PCR). Quantitative Real-Time PCR (qRT-PCR) was used to analyse the differential expression of complement-associated genes in chicken erythrocytes at 0 h, 2 h, 6 h and 10 h after the interaction between H9N2 virus and chicken erythrocytes in vitro and 3, 7 and 14 d after H9N2 virus nasal infection of chicks.3. Expression levels of C1q, C4, C1s, C2, C3, C5, C7 and CD93 were significantly up-regulated at 2 h and significantly down-regulated at 10 h. Gene expression levels of C1q, C3ar1, C4a, CFD and C5ar1 were seen to be different at each time point. The expression levels of C1q, C4, C1s, C2, C3, C5, C7, CFD, C3ar1, C4a and C5ar1 were significantly up-regulated at 7 d and the gene expression of levels of C3, CD93 and C5ar1 were seen to be different at each time point.4. The results confirmed that all the complement-associated genes were expressed in chicken erythrocytes and showed the H9N2 virus interaction with chicken erythrocytes and subsequent regulation of chicken erythrocyte complement-associated genes expression. This study reported, for the first time, the relationship between H9N2 and complement system of chicken erythrocytes, which will provide a foundation for further research into the prevention and control of H9N2 infection.


Influenza A Virus, H9N2 Subtype , Influenza in Birds , Humans , Animals , Chickens/genetics , Influenza A Virus, H9N2 Subtype/genetics , Influenza in Birds/genetics , Influenza in Birds/prevention & control , Complement C1q/genetics , Real-Time Polymerase Chain Reaction/veterinary
2.
Zhonghua Gan Zang Bing Za Zhi ; 29(11): 1041-1045, 2021 Nov 20.
Article Zh | MEDLINE | ID: mdl-34933420

Objective: To study the inhibitory effect of ezetimibe in an experimental model of human hepatoma cell line (HepaRG) infected with hepatitis B virus (HBV) positive human serum in vitro. Methods: Mature HepaRG cells were divided into a treatment group (received drugs) and a control group (did not receive drugs). In the ezetimibe prevention experiment, the cells in the treatment group was treated with drugs 2 h before infection and 24 h during infection. In the ezetimibe treatment experiment, the cells in the treatment group were treated with drugs for 6 ~ 10 days continuously after 24 hours of HBV infection. The expression of HBV DNA and intracellular cccDNA in the supernatant was detected by fluorescence quantitative PCR. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) content in the cell supernatant were detected by chemiluminescence. Analysis of variance was used to compare the differences between multiple groups. Pairwise comparisons among groups were followed by t- test with normal distribution. P < 0.05 was considered as statistically significant. Results: Ezetimibe prevention experiment showed that compared with control group, the treatment group was added with 20, 60, and 100 µmol/L ezetimibe before and during infection, and the HBV DNA content in the supernatant 2 days before was significantly reduced (P < 0.05) in the treatment group. Compared with the control group, the HBsAg expression level 2 days before was significantly reduced (P < 0.05) with the addition of 60 µmol/L ezetimibe in the treatment group. Compared with the control group, the expression level of intracellular cccDNA was significantly reduced (P < 0.05) after 10 days with the addition of 100µmol/L ezetimibe in the treatment group. Ezetimibe treatment experiment showed that cccDNA content in the cells were significantly lowered with the immediate addition of 60µmol/L ezetimibe 24 hours after infection for 10 days when compared to control group (P < 0.05). Conclusion: Ezetimibe, as a cytosolic inhibitor, has a certain inhibitory effect on hepatitis B virus infection in both prevention and treatment experiment.


Hepatitis B, Chronic , Hepatitis B , DNA, Viral , Ezetimibe , Hepatitis B/drug therapy , Hepatitis B Surface Antigens , Hepatitis B e Antigens , Hepatitis B virus/genetics , Humans , Virus Internalization
3.
Zhonghua Bing Li Xue Za Zhi ; 47(6): 438-443, 2018 Jun 08.
Article Zh | MEDLINE | ID: mdl-29886588

Objective: To study clinical and pathologic characteristics of leiomyomas of the gastrointestinal tract, and to investigate the distribution characteristics of interstitial cells of Cajal ( ICCs ) in gastrointestinal leiomyomas. Methods: One hundred and forty-seven cases of leiomyomas of gastrointestinal tract were collected at the Second Affiliated Hospital of Zhengzhou University from June 2012 to June 2017. Clinical and pathologic findings were analyzed, combined with immunohistochemistry, Alcian blue-osafranin staining and molecular study. Results: The age of patients ranged from 13-82 years with mean age of 52 years. Male to female ratio was about 1∶2. Histologically, all tumors were composed of ovoid to spindle cells arranged in short intersecting fascicles. All tumors were diffusely and strongly positive for smooth muscle antibodies, desmin and h-caldesmon by immunohistochemical staining. A prominent interspersed subpopulation of elongated/dendritic-like cells with CD117 and DOG1 positivity (accounting for 1% to 30% of all tumor cells) and negative for Alcian blue-osafranin staining was identified in all esophageal leiomyomas, 16 of 20 (80%) gastric leiomyomas and 3 of 12 small bowel leiomyomas, but none in colonic/rectal leiomyomas. Mutational analysis in 16 cases showed absence of mutation in exons 9, 11, 13 or 17 of C-KIT and exons 12 or 18 of PDGFRA. Conclusions: ICCs are identified in esophageal and gastric leiomyomas, as well as in small percentage of intestinal leiomyomas. Such findings may bring significant diagnostic pitfalls for misdiagnosis as gastrointestinal stromal tumor. Careful attention to the distribution of CD117 and DOG1 positive cells and molecular mutation analysis of C-KIT and PDGFRA may be necessary to establish the correct diagnosis.


Gastrointestinal Neoplasms/pathology , Gastrointestinal Stromal Tumors/pathology , Interstitial Cells of Cajal/pathology , Leiomyoma/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Anoctamin-1/analysis , Calmodulin-Binding Proteins/analysis , Colonic Neoplasms/chemistry , Colonic Neoplasms/pathology , DNA Mutational Analysis , Desmin/analysis , Diagnosis, Differential , Esophageal Neoplasms/chemistry , Esophageal Neoplasms/pathology , Exons , Female , Gastrointestinal Neoplasms/chemistry , Gastrointestinal Neoplasms/genetics , Gastrointestinal Stromal Tumors/chemistry , Gastrointestinal Stromal Tumors/genetics , Humans , Immunohistochemistry , Interstitial Cells of Cajal/chemistry , Leiomyoma/chemistry , Leiomyoma/genetics , Male , Middle Aged , Mutation , Neoplasm Proteins/analysis , Proto-Oncogene Proteins c-kit/analysis , Proto-Oncogene Proteins c-kit/genetics , Receptor, Platelet-Derived Growth Factor alpha/genetics , Young Adult
4.
Zhonghua Nei Ke Za Zhi ; 57(6): 450-453, 2018 Jun 01.
Article Zh | MEDLINE | ID: mdl-29925132

In order to study the significance of CD(276) and CD(133) in the development and progression of colorectal cancer (CRC), the expression of CD(276) and CD(133) was detected by immunohistochemistry in CRC and precancerous lesions. The results showed that the intensity of CD(276) and CD(133) in CRC samples was higher than that in adenoma group and non-adenoma group. CD(276) and CD(133) single and double positive expression were significantly correlated with CRC lymph node metastasis, distant metastasis and survival. CD(276) and CD(133) are significantly correlated to the development and progression of CRC and associated with poor prognosis.


Adenoma/genetics , Antigens, CD/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Lymphatic Metastasis/genetics , AC133 Antigen , Adenoma/metabolism , Aged , Antigens, CD/analysis , Biomarkers, Tumor , Disease Progression , Humans , Immunohistochemistry , Prognosis , Real-Time Polymerase Chain Reaction
5.
Zhonghua Bing Li Xue Za Zhi ; 47(4): 258-262, 2018 Apr 08.
Article Zh | MEDLINE | ID: mdl-29690664

Objective: To analyse the clinicopathologic features of gastric plexiform fibromyxoma (PF) including diagnosis, differential diagnosis, immunohistochemistry and molecular pathology. Methods: Eight cases of PF were collected from June 2006 to June 2017 at the Second Affiliated Hospital of Zhengzhou University and the First Affiliated Hospital of Zhengzhou University. The clinicopathologic findings of eight cases of PF were retrospectively analyzed, and immunohistochemistry (EnVision method) and molecular detection of glioma-associated oncogene homologue 1 (GLI1) gene translocation were performed. All cases were histologically reviewed with immunohistochemical staining for smooth muscle actin (SMA), CD10, CD117, DOG1, CD34, ER, PR, ALK and S-100. Fluorescence in situ hybridization (FISH) was used to detect the GLI1 gene translocation, and mutation of CKIT exons 9, 11, 13 and 17; and PDGFRA exons 12, 14 and 18 were identified by Sanger sequencing in four cases. Relevant literature was reviewed. Results: The study included four men and four women, age ranged from 26 to 72 years (mean 51 years). Histologically, the tumors were rich in small thin-walled blood vessels and myxoid matrix, and exhibited multiple nodular growth pattern in the gastric wall. The tumor cells were bland, spindled or oval. Immunohistochemically, all cases strongly expressed vimentin and SMA, and some expressed CD10 (4/8), desmin (3/8), H-caldesmon (5/8) and PR (5/8), but were negative for CD34, S-100, ER, ALK, CD117 and DOG1. The GLI1 gene translocation detection was performed in eight cases by FISH with three positive cases and five negative cases. Mutation analyses for exons 9, 11, 13, and 17 of CKIT genes and exons 12, 14, and 18 of the PDGFRA genes were performed and the tumors all of four tested cases were wild-type. Seven patients were followed up (ranged from 24 to 95 months, mean 50 months) after diagnosis and none of the patients had recurrence or metastasis. Conclusions: PF is a rare novel mesenchymal tumor of the stomach. Its distinct clinicopathologic features and immunohistochemical positivity for SMA, CD10 and PR can help differentiating this entity from other gastrointestinal mesenchymal tumors. FISH detection of GLI1 gene translocation offers an additional molecular diagnostic marker for the diagnosis.


Fibroma/pathology , Stomach Neoplasms/pathology , Adult , Aged , Calmodulin-Binding Proteins/metabolism , DNA Mutational Analysis , Desmin/metabolism , Diagnosis, Differential , Exons , Female , Fibroma/genetics , Fibroma/metabolism , Gastrointestinal Neoplasms/pathology , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Male , Middle Aged , Mutation , Neoplasm Recurrence, Local , Proto-Oncogene Proteins c-kit/genetics , Receptor, Platelet-Derived Growth Factor alpha/genetics , Retrospective Studies , Stomach Neoplasms/metabolism , Translocation, Genetic , Vimentin/metabolism , Zinc Finger Protein GLI1/genetics
7.
Oncogene ; 37(5): 601-615, 2018 02 01.
Article En | MEDLINE | ID: mdl-28991232

Mindin, a secreted, highly conserved extracellular matrix (ECM) protein, exerts a broad spectrum of effects on the innate immune system. However, its function in colorectal cancer (CRC) progression is not well established, and its upstream regulation mechanisms remain unclear. Contrary to previous reports, this study used two different enzyme-linked immunosorbent assay (ELISA) kits to show that the serum level of mindin was significantly decreased in CRC patients and that this decreased level is more significantly associated with the early stages of the disease. To explore the regulation of mindin, we used a bioinformatics approach to predict potential transcription factors and determined that early growth response factor (Egr)-1 directly regulates mindin expression at the transcriptional level using dual luciferase, chromatin immunoprecipitation (ChIP) DNA and electrophoretic mobility shift assay (EMSA) methods. Egr-1 regulates mindin mRNA and protein expression in CRC cells, and the protein expression of both Egr-1 and mindin was significantly decreased in tumor lesions of patients compared with adjacent control tissues. Mindin is essential for Egr-1-mediated inhibition of endothelial cell tube formation, and mindin inhibits endotheliocyte proliferation, migration and angiogenic sprouts in vitro. Overexpression of mindin suppressed xenograft tumor growth by blocking angiogenesis instead of directly suppressing CRC cell proliferation. Mechanically, mindin inhibits the hypoxia-induced HIF-1a and VEGFA protein expression in CRC cells and the phosphorylation of VEGFR-2 in endothelial cells. The results suggest that the serum level of mindin can be used as a novel biomarker for early detection of CRC and that the Egr-1/mindin axis is a potential therapeutic target for the inhibition of angiogenesis in CRC development.


Colorectal Neoplasms/genetics , Early Growth Response Protein 1/metabolism , Extracellular Matrix Proteins/genetics , Gene Expression Regulation, Neoplastic , Neoplasm Proteins/genetics , Neovascularization, Pathologic/genetics , Aged , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Cell Proliferation/genetics , Colectomy , Colon/pathology , Colon/surgery , Colorectal Neoplasms/blood , Colorectal Neoplasms/pathology , Colorectal Neoplasms/therapy , Computational Biology , Down-Regulation , Early Growth Response Protein 1/genetics , Endothelial Cells/pathology , Extracellular Matrix Proteins/blood , Extracellular Matrix Proteins/metabolism , Female , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Male , Mice, Nude , Middle Aged , Neoplasm Proteins/blood , Neoplasm Proteins/metabolism , Promoter Regions, Genetic , RNA, Messenger/metabolism , Signal Transduction/genetics , Vascular Endothelial Growth Factor Receptor-2/metabolism
8.
Eur Rev Med Pharmacol Sci ; 21(24): 5711-5716, 2017 12.
Article En | MEDLINE | ID: mdl-29272007

OBJECTIVE: To investigate the effects of extended in-patient training on swallowing function of patients with post-stroke dysphagia. PATIENTS AND METHODS: 40 patients with post-stroke dysphagia treated between January 2013-December 2015 were randomly divided into the treatment group and the control group. During the hospitalization, patients in both groups underwent routine examinations, graded swallowing training, radio frequency electrotherapy, acupuncture, dietary guidance, body position and compensation training, etc. In addition, patients in the treatment group received training with ice stimulation. The swallowing functions and prevalence rate of adverse events of the two groups during the first three months after discharge from the hospital were compared. Twenty healthy people coming for a regular checkup during the same period were also included in this study. ELISA was used to compare the peripheral blood S100ß levels of the patients with post-stroke dysphagia and the healthy population. RESULTS: After 3-month follow-up, statistical analysis showed that 70.00% patients in the treatment group regained normal (excellent/very good) swallowing function, which was much higher than the normal rate of people in the control group (25%). The difference was statistically significant (χ2 = 8.12, p<0.05). Patients in the treatment had a lower prevalence rate of adverse events (e.g. aspiration, choking, aspiration pneumonia) (5.00%) lower than the control group (25.00%), and the difference was statistically significant (χ2 = 4.02, p<0.05). ELISA assay indicated that the peripheral blood S100ß levels in patients with dysphagia were significantly higher than the healthy population (p<0.05). But compared with the control group, patients in the treatment group patients had lower S100ß level after the treatment, and the difference was statistically significant (p<0.05). CONCLUSIONS: The extended ward training could significantly improve the swallowing function of patients with post-stroke dysphagia, restore their swallowing function, and reduce adverse events of swallowing. The operations were simple, safe and practical. The training is worthy of promotion.


Acupuncture Therapy , Deglutition Disorders , Electric Stimulation Therapy , Stroke , Deglutition , Deglutition Disorders/etiology , Deglutition Disorders/therapy , Diet , Humans , Posture , Stroke/complications , Treatment Outcome
9.
Sci Rep ; 6: 21967, 2016 Feb 25.
Article En | MEDLINE | ID: mdl-26912191

The plastic flow of bulk metallic glasses (BMGs) is characterized by intermittent bursts of avalanches, and this trend results in disastrous failures of BMGs. In the present work, a double-side-notched BMG specimen is designed, which exhibits chaotic plastic flows consisting of several catastrophic avalanches under the applied loading. The disastrous shear avalanches have, then, been delayed by forming a stable plastic-flow stage in the specimens with tailored distances between the bottoms of the notches, where the distribution of a complex stress field is acquired. Differing from the conventional compressive testing results, such a delaying process is independent of loading rate. The statistical analysis shows that in the specimens with delayed catastrophic failures, the plastic flow can evolve to a critical dynamics, making the catastrophic failure more predictable than the ones with chaotic plastic flows. The findings are of significance in understanding the plastic-flow mechanisms in BMGs and controlling the avalanches in relating solids.

10.
Neoplasma ; 62(6): 872-80, 2015.
Article En | MEDLINE | ID: mdl-26458321

Hepatocellular carcinoma (HCC) is among the most common cancers in the world with a low survival rate. Our previous study showed Short chain enoyl-CoA hydratase (ECHS1) could bind to HBsAg (HBs) and that ECHS1's localization in mitochondria induced HepG2 cell apoptosis. However, the role of the ECHS1 in energy metabolism and autophagy during hepatocellular carcinoma development remains undefined. We aimed to determine what ECHS1 does to energy metabolism and its effects on HCC progression. We performed CCK-8, EdU assays in hepatocellular carcinoma cell lines (HepG2 and HuH7) with stable ECHS1 knock-down. ATP and NADP+/NADPH levels were measured using an colorimetric assay. Our data demonstrated that ECHS1 silencing inhibited cell proliferation and induced autophagy. ECHS1 knockdown did not increase fatty acid synthesis, but decreased cellular ATP. This resulted in AMP-activated protein kinase (AMPK) activation and induced HCC cell autophagy. Our results showed that silencing ECHS1 to attenuate proliferation and induce autophagy may make it a novel cancer therapy target.

11.
Parasite Immunol ; 36(12): 647-57, 2014 Dec.
Article En | MEDLINE | ID: mdl-25099746

Our and others' previous studies have shown that Schistosoma japonicum (SJ) infection can inhibit allergic reactions. We recently reported that DCs played an important role in SJ infection-mediated inhibition of allergy, which was associated with enhanced IL-10 and T regulatory cell responses. Here, we further compared the role of CD8α(+) DC and CD8α(-) DC subsets for the inhibitory effect. We sorted CD8α(+) DC (SJCD8α(+) DC) and CD8α(-) DC (SJCD8α(-) DC) from SJ-infected mice and tested their ability to modulate allergic responses in vivo. The data showed that the adoptive transfer of SJCD8α(-) DC was much more efficient than SJCD8α(+) DC for the suppression of allergic airway eosinophilia, mucus overproduction, antigen-specific IgE responses, and Th2 cytokines (IL-4 and IL-5). More importantly, we found that the transfer of SJCD8α(-) DC, but not SJCD8α(+) DC, significantly increased IL-10 and TGF-ß production following OVA exposure. As control, the transfer of DC subsets from naïve mice had no significant effect on allergic inflammation. In addition, SJCD8α-DC expressed significantly higher IL-10 but lower IL-12, CD80 and CD86 than SJCD8α(+) DC, fitting a tolerogenic phenotype. The results suggest that CD8α(-) DC is the predominant DC subset which is involved in the parasitic infection-mediated inhibition of allergic inflammation and possibly through enhancing immunomodulatory cytokine (IL-10 and TGF-ß) production.


Dendritic Cells/immunology , Hypersensitivity/immunology , Schistosomiasis japonica/immunology , Adoptive Transfer , Animals , Antigens, Helminth/immunology , CD11b Antigen , Dendritic Cells/cytology , Female , Hypersensitivity/prevention & control , Interleukin-10/immunology , Mice , Mice, Inbred BALB C , Ovalbumin , Pneumonia/chemically induced , Pneumonia/immunology , T-Lymphocytes, Helper-Inducer/immunology , Transforming Growth Factor beta/immunology
12.
Clin Radiol ; 69(1): 13-7, 2014 Jan.
Article En | MEDLINE | ID: mdl-24156795

AIM: To investigate the feasibility and advantages of cholangiobiopsy during percutaneous transhepatic cholangiography in the histopathological diagnosis of anastomotic stenosis after cholangiojejunostomy for malignant obstructive jaundice. MATERIALS AND METHODS: Using biopsy forceps, specimens were collected from the site of stenosis in patients with recurrent jaundice (n = 24) who had previously undergone cholangiojejunostomy for malignant obstructive jaundice. RESULTS: Stenosis occurred in all patients at the biliary-enteric anastomosis based on percutaneous transhepatic cholangiography, and was the location of the biopsy. Satisfactory specimens were obtained from 22 out of 24 patients. The sensitivity was 91.7% (22/24). Tumour tissue was obtained in 18 cases, confirming disease recurrence. Histopathological changes in four patients were diagnosed as fibroplasia and/or inflammation. These were considered cicatricial stenoses based on histopathological, imaging, and laboratory findings. The remaining two histopathology-negative patients were proven to have recurrent tumour based on imaging, laboratory, and follow-up data. No complications occurred during biopsy, including gastrointestinal haemorrhage or perforation. Either cholangial drainage and/or an inner stent was used following biopsy, which resulted in a noticeable decrease in jaundice postoperatively (p < 0.05). CONCLUSION: Percutaneous transhepatic cholangiobiopsy using biopsy forceps for the diagnosis of anastomotic stenosis after cholangiojejunostomy for malignant biliary obstructive jaundice is easy to perform and safe, with a high level of sensitivity. Interventional therapies, such as percutaneous transhepatic cholangial drainage and stent placement, can be performed concurrently, markedly improving the symptoms of patients with obstructive jaundice.


Cholangiocarcinoma/surgery , Cholangiography , Gallbladder Neoplasms/surgery , Jaundice, Obstructive/surgery , Jejunostomy , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology , Adult , Aged , Anastomosis, Surgical , Biopsy , Cholangiocarcinoma/pathology , Constriction, Pathologic , Female , Gallbladder Neoplasms/pathology , Humans , Male , Middle Aged , Sensitivity and Specificity , Stents
13.
Bioresour Technol ; 99(5): 1465-73, 2008 Mar.
Article En | MEDLINE | ID: mdl-17446063

The chemical modification of sugarcane bagasse with succinic anhydride using pyridine as solvent after ultrasound irradiation was studied. The optimized parameters included ultrasound irradiating time 0-50 min, reaction time 30-120 min, succinic anhydride concentration by the ratio of dried sugarcane bagasse to succinic anhydride from 1:0.25 to 1:1.50, and reaction temperature 75-115 degrees C are required in the process. The extent of succinoylation was measured by the weight percent gain (WPG), which increased with increments of reaction time, succinic anhydride concentration, and reaction temperature. The ultrasound irradiation has a positive effect on bagasse succinoylation process. On the other hand, the ultrasonic pre-treatment application broke down the cell wall polymers, resulting in, therefore, a negative effect on the WPG. Evidences of succinoylation were also provided by FT-IR and CP MAS (13)C NMR and the results showed that the succinoylation at C-2 and C-3 occurred. The thermal stability of the succinylated bagasse decreased upon chemical modification.


Cellulose/chemistry , Cellulose/radiation effects , Refuse Disposal/methods , Saccharum/chemistry , Ultrasonics , Industrial Waste , Succinic Anhydrides/chemistry
14.
Carbohydr Res ; 342(7): 919-26, 2007 May 21.
Article En | MEDLINE | ID: mdl-17324384

The homogeneous chemical modification of sugarcane bagasse cellulose with succinic anhydride using 1-allyl-3-methylimidazolium chloride (AmimCl) ionic liquid as a reaction medium was studied. Parameters investigated included the molar ratio of succinic anhydride/anhydroglucose units in cellulose in a range from 2:1 to 14:1, reaction time (from 30 to 160min), and reaction temperature (between 60 and 110 degrees C). The succinylated cellulosic derivatives were prepared with a low degree of substitution (DS) ranging from 0.071 to 0.22. The results showed that the increase of reaction temperature, molar ratio of SA/AGU in cellulose, and reaction time led to an increase in DS of cellulose samples. The products were characterized by FT-IR and solid-state CP/MAS (13)C NMR spectroscopy, and thermal analysis. It was found that the crystallinity of the cellulose was completely disrupted in the ionic liquid system under the conditions given. The data also demonstrated that homogeneous modification of cellulose with succinic anhydride in AmimCl resulted in the production of cellulosic monoester. The thermal stability of the succinylated cellulose decreased upon chemical modification.


Cellulose/chemistry , Ionic Liquids/chemistry , Saccharum/chemistry , Succinic Anhydrides/chemistry , Calorimetry, Differential Scanning , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Spectroscopy, Fourier Transform Infrared , Temperature , Thermogravimetry , Time Factors
15.
Carbohydr Res ; 341(16): 2677-87, 2006 Nov 27.
Article En | MEDLINE | ID: mdl-16934239

In this study, we investigated the physicochemical properties of the cellulosic preparations obtained from both untreated perennial ryegrass leaves and de-juiced leaves. It was found that treatment at 22 degrees C with 18% NaOH and 18% KOH for 2h, and 10% NaOH and 10% KOH for 16 h yielded 28.2%, 28.8%, 22.7%, 23.4%, respectively, of 'cellulose' residue from untreated ryegrass leaves and 35.7%, 36.8%, 32.8% and 34.6%, respectively, from the de-juiced leaves. For each cellulosic fraction, the glucose content was 71.6%, 69.6%, 67.8%, 66.7%, 69.7%, 68.6%, 63.9% and 61.7%, respectively. The structure of the cellulose samples was examined using FTIR and CP/MAS (13)C NMR spectroscopy and X-ray diffraction. The cellulosic preparations were free of bound lignin except for noticeable amounts of residual hemicelluloses (28.4-38.3%), and had intrinsic viscosities between 275.1 and 361.0 mL/g, along with molecular weights from 144,130 to 194,930 g/mol. This study found that the cellulose samples isolated from both de-juiced ryegrass leaves and the untreated leaves had a much lower percent crystallinity (33.0-38.6%) than that from wood-based fibres (60-70%) and had much shorter fibres (0.35-0.49 mm) than those of either cereal straws, bagasse or wood. In addition, a partial disruption of the hydrogen bonds and microfibrils may occur during the de-juicing process by mechanical activity, which results in a decreased cellulose crystallinity and fibre length. These findings are significant in relation to hydrolysing ryegrass cellulose for bio-ethanol production.


Cellulose/chemistry , Lolium/chemistry , Carbon Isotopes , Chemical Phenomena , Chemistry, Physical , Nuclear Magnetic Resonance, Biomolecular , Plant Leaves/chemistry , Spectroscopy, Fourier Transform Infrared , Viscosity , X-Ray Diffraction
16.
Carbohydr Res ; 341(12): 2073-82, 2006 Sep 04.
Article En | MEDLINE | ID: mdl-16750181

Sequential three-stage treatments with 80% EtOH containing 0.2% NaOH, 2.5% H2O2-0.2% EDTA containing 1.5% NaOH and 2.5% H2O2-0.2% TAED containing 1.0% NaOH at 75 degrees C for 3h released 8.0% and 10.4%, 79.1% and 77.0% and 12.9% and 12.5% of the original hemicelluloses from perennial grass and cocksfoot grass, respectively. It was found that the four alkaline peroxide-soluble hemicellulosic fractions contained higher amounts of xylose (33.4-38.2%), uronic acids (9.3-15.3%) and rhamnose (3.0-3.9%), but were lower in glucose (25.1-28.3%), galactose (13.3-15.3%) and mannose (0.4-1.5%) than those of the two alkaline EtOH-soluble hemicellulosic fractions in which glucose (32.9-36.0%), xylose (20.1-22.6%), arabinose (14.1-21.4%), galactose (16.6-19.9%), mannose (4.1-9.9%) and uronic acids (3.4-7.4%) were the major sugar components. 13C NMR spectroscopy confirmed that all the six hemicellulosic fractions were composed of galactoarabinoxylans, 4-O-methylglucuronoarabinoxylans and beta-glucan. In addition, the studies showed that the four alkaline peroxide-soluble hemicellulosic fractions were more linear and acidic and had larger molecular weights (Mw, 28,400-38,650 g mol(-1)) than those of the two alkaline EtOH-soluble hemicellulosic fractions (Mw, 16,460-17,420 g mol(-1)).


Chemical Fractionation/methods , Dactylis/chemistry , Lolium/chemistry , Polysaccharides/chemistry , Galactose/chemistry , Glucose/chemistry , Magnetic Resonance Imaging/methods , Mannose/chemistry , Peroxides/chemistry , Polysaccharides/isolation & purification , Rhamnose/chemistry , Uronic Acids/chemistry , Xylose/chemistry
17.
Apoptosis ; 11(3): 327-36, 2006 Mar.
Article En | MEDLINE | ID: mdl-16520896

Cell volume can be altered by two different ways, swelling and shrinkage. Cell swelling is regulated by volume-regulated Cl- channel (VRC). It is not well understood whether shrinkage is regulated by VRC. We previously found that antisense oligonucleotide specific to ClC-3 (ClC-3 antisense) prevented cell proliferation, which was related to cell swell volume regulation. In the present study, we further studied the role of ClC-3 Cl- channel in cell apoptosis which was related to cell shrinkage volume regulation by using antisense oligonucleotide specific to ClC-3 (ClC-3 antisense) and ClC-3 cDNA transfection techniques. We found that thapsigargin (TG), a specific inhibitor of the endoplasmic reticulum calcium ATPase, evoked apoptotic morphological changes (including cytoplasmic blebbing, condensation of nuclear chromatin, and the formation of apoptotic bodies), DNA laddering, and caspase-3 activation in PC12 cells (Pheochromocytoma-derived cell line). TG increased the cell apoptotic population with a decrease in cell viability. These effects were consistent with the decrease in endogenous ClC-3 protein expression, which was also induced by TG. Overexpression of ClC-3 significantly inhibited TG effect on PC12 cell apoptosis, whereas the ClC-3 antisense produced opposite effects and facilitated apoptosis induced by TG. Our data strongly suggest that ClC-3 channel in PC12 cells mediates TG-induced apoptotic process through inhibitory mechanism. Thus, it appears that ClC-3 Cl- channel mediates both cell proliferation and apoptosis through accelerative and inhibitory fashions, respectively.


Apoptosis/physiology , Chloride Channels/metabolism , Enzyme Inhibitors/metabolism , Thapsigargin/metabolism , Animals , Caspase 3/metabolism , Cell Shape , Cell Size , Chloride Channels/genetics , DNA Fragmentation , Enzyme Activation , Oligonucleotides, Antisense/genetics , Oligonucleotides, Antisense/metabolism , PC12 Cells , Rats
18.
Analyst ; 126(5): 698-702, 2001 May.
Article En | MEDLINE | ID: mdl-11394317

A modification of the aluminium-lumogallion fluorescence measurement in the presence of the non-ionic surfactant Triton X-100 is presented. The detection limit for dissolved Al is 0.7 nM, with a relative standard deviation of 3.6% at an Al level of 5.0 nM. Compared with previously reported methods in the literature, the method described here is free from matrix effects and can be used for the determination of aluminium in fresh, estuarine and saline waters. The interferences from iron and fluoride were minimized by the addition of o-phenanthroline and Be2+, respectively. The analysis of NIST SRM 1643C and PRC standard 2430101 by the proposed method provides results consistent with the certified values. A successful inter-laboratory calibration exercise also demonstrates the merit of the proposed method for the determination of Al in environmental and marine sciences.


Aluminum/analysis , Water Pollutants, Chemical/analysis , Octoxynol , Spectrometry, Fluorescence , Surface-Active Agents
19.
Burns ; 24(2): 162-5, 1998 Mar.
Article En | MEDLINE | ID: mdl-9625244

Fourteen cases suffering full-thickness burns of more than 70 per cent total body surface area (TBSA) have been successfully treated during the last 8 years (1988-1995). Among these patients, 10 cases suffered from burns of more than 90 per cent TBSA. Five cases had full-thickness burns of 80-90 per cent TBSA. Escharectomy, followed by coverage of wounds with a homograft to the lower surface of which, adjacent to the wound bed, microautoskin grafts had been attached was employed to close wounds in the early stages after burn. The remaining non-surgically treated wound was treated by exposure and topical silver sulfadiazine. The temperature and humidity of the ward was controlled by air conditioning and dehumidification. Aggressive excision of eschar and auto-skingrafting was carried out 3 weeks post-injury. Strictly limiting the uncovered wound to less than 5 per cent appeared to be the major effective measure in preventing burn infection.


Anti-Infective Agents, Local/therapeutic use , Burns/therapy , Silver Sulfadiazine/therapeutic use , Skin Transplantation , Administration, Topical , Adult , Anti-Bacterial Agents , Anti-Infective Agents, Local/administration & dosage , Burns/diagnosis , Child , Drug Therapy, Combination/therapeutic use , Female , Fluid Therapy , Follow-Up Studies , Humans , Male , Retrospective Studies , Shock, Traumatic/therapy , Silver Sulfadiazine/administration & dosage , Transplantation, Homologous , Trauma Severity Indices , Treatment Outcome , Wound Healing , Wound Infection/prevention & control
20.
Am J Physiol ; 261(3 Pt 1): G417-25, 1991 Sep.
Article En | MEDLINE | ID: mdl-1887890

Our aim in this study was to determine the effect of variations in intrabolus pressure on esophageal peristalsis. In five cats, intrabolus pressure was altered by increasing intragastric pressure to 20-45 mmHg by use of a pressure cuff to compress the abdomen. In each cat, increases in intragastric pressure were associated with comparable increases in pressure of the esophageal bolus while the bolus was in the distal esophagus during esophageal peristalsis. Secondary peristalsis induced by a 5-ml injection of barium into the proximal esophagus was recorded by synchronized videofluoroscopy and esophageal manometry. Graded increases in intrabolus pressure caused an increased prevalence of ineffective, incomplete peristaltic sequences that did not completely clear barium from the esophagus. At intragastric pressures greater than 45 mmHg, 63% of the peristaltic sequences were incomplete. Increases in intrabolus pressure elicited by increased intragastric pressure also caused 1) slowing of the peristaltic wave in the distal esophagus, 2) increased pressure wave duration in the distal esophagus, 3) increased esophageal diameter, and 4) increased duration of lower esophageal sphincter opening. The incidence of retrograde bolus escape was inversely related to the difference between peristaltic wave amplitude and intrabolus pressure. A pressure difference of greater than 20 mmHg prevented retrograde barium escape at all esophageal levels, whereas a difference of less than 20 mmHg was generally associated with retrograde escape of barium in the distal esophagus. We conclude that an increase in intrabolus pressure causes an increase in esophageal distension that is transduced into alterations of esophageal peristalsis by either a myogenic or neural mechanism.


Abdomen/physiology , Esophagus/physiology , Muscle, Smooth/physiology , Peristalsis/physiology , Animals , Cats , Female , Fluoroscopy , Gastrointestinal Transit/physiology , Male , Manometry , Pressure , Stomach/physiology
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