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Biomedical subjects

Li Zhou

Publications and source records attributed to Li Zhou.

At least 55 records · Page 3Linked to original sources
PubMed2006

[Experimental study of the therapeutic effect and mechanism of "Shenxian Fuyuan capsule" on chronic renal failure in rats].

OBJECTIVE: To study the therapeutic effect and mechanism of "Shenxian Fuyuan Capsule" (SXFYC) on chronic renal failure in rats with 5/6 nephrectomy. METHODS: The animal model with chronic renal failure was established by using the method of 5/6 nephrectomy. The animals were randomly divided into four groups: SXFYC treatment group, losartan treatment group, control group and pseudo-operation group (normal group). Since the next day after operations, the rats in the SXFYC treatment group and the losartan treatment group had been intragastrically administrated with SXFYC 300 mg/kg x d and losartan 150 mg/kg x d respectively. The rats in the normal group and control group were fed with sodium chloride twice a day. Four, eight and twelve weeks later, histological and biochemical tests were undertaken to examine changes of the remnant kidney such as alpha-SMA, collagen I, blood urea nitrogen, serum creatinine and proteinuria. The connective tissue growth factor (CTGF) mRNA was detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Both SXFYC and losartan ameliorated the histological change of remnant kidney, decreased the level of CTGF mRNA, serum creatinine and proteinuria (P<0.01). There were no significant differences between the SXFYC and losartan treatment groups (P>0.05). CONCLUSION: "Shenxian Fuyuan Capsule" can improve the renal function of the 5/6 nephrectomized rats. It performs as well as losartan. "Shenxian Fuyuan Capsule" might have played an important role in preventing CTGF-mediated renal fibrosis in the 5/6 nephrectomized rats.

Animals↗
PubMed2006

[Clinical study of periocline on peri-implantitis treatment].

OBJECTIVE: To evaluate the clinical outcome and the effects of treating peri-implantitis with periocline. METHODS: Thirty-two sites in 32 implants with peri-implantitis were treated with periocline. The parameters including plaque index, probing depth (PD) of pocket, sulcular bleeding index (SBI) were measured at baseline, 1, 3, 6 and 12 weeks after treatment and followed up for 6 months. RESULTS: Statistically significant decrease (P < 0.05) in SBI, and PD occurred at all time intervals compared to baseline. The treatment could last for at lest four weeks in peri-implantitis cases without fistula. CONCLUSIONS: Periocline could be safely and effectively used in treating peri-implantitis in cases without peri-implant fistula. Peri-implantitis with fistula should be treated in combination with surgical methods, and periocline can also be used to control inflammation before surgery.

Adult↗
PubMed2006

[Effects of rosiglitazone on the expression of beta1, integrin and ICAM-1 in high glucose-induced rat glomerular mesangial cells].

OBJECTIVE: To observe the effects of PPARgamma activators thiazolidinediones (Rosiglitazone) on the expression of intercellular adhesion molecule-1 (ICAM-1) and beta1 integrin in high glucose-induced rat glomerular mesangial cells (GMC) in order to elucidate the relationship between PPARgamma and adhesion molecules. METHODS: Rat HBZY-1 GMCs were cultured in vitro and divided into 9 groups: Normal Glucose group (N), High Glucose group (H), Mannitiol group (M), Normal and High Glucose plus 1, 5, 10 micromol/L Rosiglitazone. Every group was treated for 24 hours. The expression of ICAM-1 was measured by immunohistochemistry, the expression of beta1 integrin by indirect immunofluorescence staining and flow cytometry. RESULTS: It was found that high glucose can significantly increase the expression of ICAM-1 and beta1 integrin in GMCs, which is independent of the osmotic pressure. Rosiglitazone can inhibit the expression of ICAM-1 and beta1 integrin in normal and high glucose treated GMCs, and the inhibition is stronger in high glucose treated-group, which is in a dose-dependent manner. The expression of beta1 integrin is positively correlated with ICAM-1. CONCLUSION: Adhesion molecules involves in the pathogenesis of diabetic nephropathy (DN). PPARgamma activators-Rosiglitazone may exert effect on mesangial expansion and glomerulosclerosis in DN through the inhibition of expressions of adhesion molecules induced by high glucose.

Animals↗
PubMed2006

[A randomized controlled trial of acupuncture treatment of acute ischemic stroke].

OBJECTIVE: To explore effects of acupuncture on ability of daily living (ALD) and the incidence rate of disability and mortality of the patient of acute ischemic stroke. METHODS: Forty patients with acute ischemic stroke were randomly assigned to an acupuncture group and a control group, 20 cases in each group. The treatment group were treated with acupuncture for 3-4 weeks, 5 times each week, and routine therapy. The control group were treated with routine therapy alone. RESULTS: No statistically significant differences between the two groups in the score of neurological defection, and the incidence rate of disability and mortality at following survey of 3 and 6 months were found. CONCLUSION: Acupuncture is safe and feasible for stroke at early stage.

Acupuncture↗
PubMed2005

Disordered osteoclast formation in RAGE-deficient mouse establishes an essential role for RAGE in diabetes related bone loss.

The mechanisms underlying diabetes-mediated bone loss are not well defined. It has been reported that the advanced glycation endproducts (AGEs) and receptor for AGEs (RAGEs) are involved in diabetic complications. Here, mice deficient in RAGE were used as a model for investigating the effects of RAGE on bone mass. We found that RAGE-/- mice have a significantly increased bone mass and bone biomechanical strength and a decreased number of osteoclasts compared to wild-type mice. The serum levels of IL-6 and bone breakdown marker pyridinoline were significantly decreased in RAGE-/- mice. RAGE-/- mice maintain bone mass following ovariectomy, whereas wild-type mice lose bone mass. Furthermore, osteoclast-like cells do express RAGE mRNA. Our data therefore indicate that RAGE serves as a positive factor to regulate the osteoclast formation, directly implicates a role for RAGE in diabetes-promoted bone destruction, and documents that the AGE-RAGE interaction may account for diabetes associated bone loss.

Animals↗
PubMed2005

Methane sorption in ordered mesoporous silica SBA-15 in the presence of water.

Methane or natural gas is a practical alternative fuel of vehicles. To develop more efficient technology of on-board storage, a possibility of using SBA-15 as the methane carrier is tested. An ordered mesoporous silica molecular sieve SBA-15 is synthesized aimed at collecting the data of methane sorption in the presence of water. The synthesized material is examined with SEM, TEM, and XRD analyses, and the hexagonal channel structure is confirmed. Its textual parameters are evaluated on the basis of the adsorption data for nitrogen at 77 K, and it gives the results of 802 m2/g for the specific surface area, 1.31 cm3/g for the pore volume, a narrow pore size distribution centered at 7.7 nm, and 4 nm for the width of the partition wall. Methane sorption isotherms on SBA-15 are collected with a volumetric method for samples of different contents of water, and the enhancement of the sorption capacity due to the presence of water is observed. A discussion on the mechanism of the sorption enhancement is presented.

Journal Article↗
PubMed2005

[Related factor analysis of avascular necrosis of the femoral head after internal fixation with cannulated screws in femoral neck fractures].

OBJECTIVE: To observe the accident of avascular necrosis of the femoral head after internal fixation with cannulated screws in femoral neck fractures and analysis of the related factors. METHODS: 212 cases of femoral neck fracture treated with cannulated screws between Sep. 1989 and Dec. 1999 were reviewed retrospectively. The average age was 45.2 years old, ranging from 13 to 70 years. Among the fractures, 3 were Garden stage I, 32 were Garden stage II, 107 were Garden stage III, 53 were Garden stage IV, and 17 unclassified. Average duration of follow-up was 32.7 months, ranging from 12 to 101 months. RESULTS: Fracture healing occurred in 203 cases (95.8%). Avascular necrosis of the femoral head occurred in 70 cases (33.0%) and late collapse developed in 30 cases (14.3%). The rate of the avascular necrosis and late collapse of the femoral head according to the Garden stage was 0/0, Garden stage I; 6.3%/0, Garden stage II; 33.6%/15.9%, Garden stage III; 49.1%/20.8%, Garden stage IV. Avascular necroses of the femoral head were observed within 3 years in most cases (95.7%). Correlation analysis shows Garden stage of the fracture was the major factor contributed to the accident of avascular necrosis and late collapse of the femoral head. It also shows the low risk of avascular necrosis and late collapse of the femoral head was related to the patient's age over 60; time of surgery within 14 days and Garden's reduction index within 155-180 degrees on both AP and Lateral views. CONCLUSION: Garden stage of the fracture is the major factor contributed to the accident of avascular necrosis and late collapse of the femoral head, emergency operation and good reduction is beneficial to reduce the accident of avascular necrosis of femoral head.

Adolescent↗
PubMed2005

Molecular cloning and expression pattern of 14 kDa apolipoprotein in orange-spotted grouper, Epinephelus coioides.

A novel fish-specific apolipoprotein (apo-14 kDa) has been recently cloned from eel and pufferfish. However, its expression pattern has not been elucidated. In this study, EcApo-14 has been screened from hypothalamic cDNA library of male orange-spotted grouper, which shows 62.9%, 51%, 46.9%, 43.2%, and 31.9% identities to Apo-14 of European flounder, pufferfish, Japanese eel, gibel carp, and grass carp, respectively. RT-PCR analysis reveals that this gene is first transcribed in neurula embryos and maintains a relatively stable expression level during the following embryogenesis. EcApo-14 transcripts are at a very high level during embryonic and early larval development in the yolk syncytial layer (YSL), and decrease in YSL and form intense staining in liver at 3 days after hatching. In adult tissues, EcApo-14 is predominantly expressed in liver and brain. The data suggested that EcApo-14 might play an important role in liver and brain morphogenesis and growth.

Amino Acid Sequence↗
PubMed2005

Intron 1 sequences are required for pancreatic expression of the human proglucagon gene.

The mammalian proglucagon gene is expressed in pancreatic islet A-cells, intestinal L-cells, and select neurons of the brain, where posttranslational processing results in the liberation of a unique profile of peptides. Despite the importance of proglucagon-derived peptides in human biology, little is known about the regulation of the human gene, as the rat gene has been the preferred model for understanding the regulation of proglucagon gene expression. Previously, we have shown that although the immediate promoter region of the rat proglucagon gene is sufficient for expression in pancreatic islet cells, the homologous human proglucagon promoter sequences are not sufficient. We have now used a comparative genomic approach to identify noncoding sequences near the human proglucagon gene that are conserved among mammals, and thus potentially are regulatory sequences. Our alignments identified three evolutionarily conserved noncoding regions (ECR), one is the immediate promoter region (ECR1), the second is about 5 kb 5' to the mRNA start site (ECR2), and the third is near the 3' end of the first intron (ECR3). Our in vitro transient transfection assays with reporter gene constructs that include the human ECR3 support expression in rodent islet cell lines. Complementary studies with transgenic mice possessing a reporter gene regulated by a human proglucagon gene promoter-intron 1 (including ECR3) sequences express the reporter gene in the pancreas, as well as the intestine and selected neurons. These studies suggest that conserved sequences within intron 1 of the human proglucagon gene are important for expression in the pancreas.

Animals↗
PubMed2005

Hydrogen and methane sorption in dry and water-loaded multiwall carbon nanotubes.

Both H2 and CH4 are clean energy sources. Adsorption was considered a measure to enhance their storage, and many efforts have been dedicated to creating novel materials including carbon nanotubes as efficient carriers for them. In order to understand the uptake mechanism and the viability of practical application, eight adsorption isotherms of H2 on a sample of multiwall carbon nanotubes were collected. The heat of adsorption was determined and an isotherm model was presented. Isotherms of CH4 on the same sample were also collected. While the adsorption on dry samples behaves similarly to that of H2, the sorption behavior of CH4 in the water-loaded sample is quite different and five times higher uptake capacity was observed in the wet sample due to the formation of methane hydrates. However, carbon nanotubes are unlikely to be used as an energy carrier due to its limited surface area and pore volume.

Adsorption↗
PubMed2005

Effect of metallic ions on silk formation in the Mulberry silkworm, Bombyx mori.

A protein conformation transition from random coil and/or helical conformation to beta-sheet is known to be central to the process used by silk-spinning spiders and insects to convert concentrated protein solutions to tough insoluble threads. Several factors including pH, metallic ions, shear force, and/or elongational flow can initiate this transition in both spiders and silkworms. Here, we report the use of proton induced X-ray emission (PIXE), inductively coupled plasma mass spectroscopy (ICP-MS) and atomic adsorption spectroscopy (AAS) to investigate the concentrations of six metal elements (Na, K, Mg, Ca, Cu, and Zn) at different stages in the silk secretory pathway in the Bombyx mori silkworm. We also report the use of Raman spectra to monitor the effects of these six metallic ions on the conformation transition of natural silk fibroin dope and concentrated regenerated silk fibroin solution at concentrations similar to the natural dope. The results showed that the metal element contents increased from the posterior part to the anterior part of silk gland with the exception of Ca which decreased significantly in the anterior part. We show that these changes in composition can be correlated with (i) the ability of Mg2+, Cu2+, and Zn2+ to induce the conformation transition of silk fibroin to beta-sheet, (ii) the effect of Ca2+ in forming a stable protein network (gel), and (iii) the ability of Na+ and K+ to break down the protein network.

Animals↗
PubMed2005

A temporal constraint structure for extracting temporal information from clinical narrative.

INTRODUCTION: Time is an essential element in medical data and knowledge which is intrinsically connected with medical reasoning tasks. Many temporal reasoning mechanisms use constraint-based approaches. Our previous research demonstrates that electronic discharge summaries can be modeled as a simple temporal problem (STP). OBJECTIVE: To categorize temporal expressions in clinical narrative text and to propose and evaluate a temporal constraint structure designed to model this temporal information and to support the implementation of higher-level temporal reasoning. METHODS: A corpus of 200 random discharge summaries across 18 years was applied in a grounded approach to construct a representation structure. Then, a subset of 100 discharge summaries was used to tally the frequency of each identified time category and the percentage of temporal expressions modeled by the structure. Fifty random expressions were used to assess inter-coder agreement. RESULTS: Six main categories of temporal expressions were identified. The constructed temporal constraint structure models time over which an event occurs by constraining its starting time and ending time. It includes a set of fields for the endpoint(s) of an event, anchor information, qualitative and metric temporal relations, and vagueness. In 100 discharge summaries, 1961 of 2022 (97%) identified temporal expressions were effectively modeled using the temporal constraint structure. Inter-coder evaluation of 50 expressions yielded exact match in 90%, partial match with trivial differences in 8%, partial match with large differences in 2%, and total mismatch in 0%. CONCLUSION: The proposed temporal constraint structure embodies a sufficient and successful implementation method to encode the diversity of temporal information in discharge summaries. Placing data within the structure provides a foundational representation upon which further reasoning, including the addition of domain knowledge and other post-processing to implement an STP, can be accomplished.

Database Management Systems↗
PubMed2005

Electroanatomical systems to guided circumferential pulmonary veins ablation for atrial fibrillation: initial experience from comparison between the Ensite/NavX and CARTO system.

BACKGROUND: The circumferential pulmonary vein ablation (CPVA) has been proved effective for atrial fibrillation (AF) treatment and is becoming more widely accepted and practiced. This study aims to evaluate the characteristics of the CARTO and the Ensite/NavX system and draw a comparison between them on the aspects of procedural parameters and clinical effectiveness. METHODS: Seventy-five cases with paroxysmal or chronic symptomatic AF were randomly assigned to CPVA procedure guided by the Ensite/NavX system (group I, n = 40) and by the CARTO system (group II, n = 35). After successful transseptal procedure, the geometry of left atrium was created under the guidance of the two systems. Radiofrequency energy was applied to circumferentially ablate tissues out of pulmonary veins' (PVs') ostia. In cases with chronic AF, linear ablation was applied to modify the substrate of left atrium (LA). The endpoint of the procedure was complete PVs isolation. RESULTS: Seventy-five cases underwent the procedure successfully. The total procedure and fluoroscopic durations in group II were significantly shorter than in group I [(150 +/- 23) min and (18 +/- 17) min versus (170 +/- 34) min and (25 +/- 16) min, P = 0.03 and 0.04, respectively]. There was no significant difference in the fluoroscopic and procedure durations for geometry creation between group I and group II [(8 +/- 4) min and (16 +/- 11) min versus (5 +/- 4) min and (14 +/- 8) min, respectively]. The fluoroscopic durations for CPVA were (15 +/- 5) min in group I versus (10 +/- 6) min in group II (P = 0.05), and the CPVA procedural durations were significantly shorter in group II than in group I [(18 +/- 11) min versus (25 +/- 10) min, P = 0.04]. AF was terminated by radio frequency delivery in 14 cases (35%) in group I versus 5 cases (14%) in group II (P = 0.035). After CPVA complete PV isolation was attained in 26 cases (65%) in group I versus 11 cases (31%) in group II (P = 0.004). During a mean follow-up of 7 months, 32 (80%) cases in group I and 24 (69%) cases in group II were arrhythmia-free (P = 0.06). One case developed pericardium effusion and another one case was found to have intestinal artery thrombosis in group II. One case had moderate hemothorax in group I. All the complications were cured by proper treatment. No PV stenosis was observed. CONCLUSIONS: The CPVA procedure for atrial fibrillation is effective and safe. Although there is difference between the CARTO and the Ensite/NavX system, the CPVA procedure guided by either of them yields similar clinical results.

Adult↗
PubMed2005

Combined human growth hormone and lactulose for prevention and treatment of multiple organ dysfunction in patients with severe chronic hepatitis B.

AIM: To evaluate the efficiency and safety of combined recombinant human growth hormone (rhGH) and lactulose for treatment and/or prevention of multiple organ dysfunction in patients with chronic severe hepatitis B. METHODS: Forty-eight inpatients with chronic severe hepatitis B were randomly divided into rhGH group (n=28) and control group (n=20). In rhGH group, 4-4.5 IU of rhGH was injected intramuscularly once daily for 2-4 wk, and 100 mL of enema containing 30 mL of lactulose, 2 g of metronidazole and 0.9% saline was administered every 2 d for 2-4 wk. Their symptoms and complications were noted. Liver and kidney functions were analyzed by an Olympus analyzer. Serum GH, IGF-1, IGFBP1 and IGFBP3 were measured by ELISA. RESULTS: Clinical symptoms of 90% of these patients in rhGH group were obviously improved. The total effectiveness in rhGH group was better than that in control group (75% vs 40%, P<0.05). After 2- and 4-wk treatment of rhGH respectively, serum albumin (26.1+/-4.1 vs 30.2+/-5.3, 31.9+/-5.1 g/L), prealbumin (79.6+/-28.0 vs 106.6+/-54.4, 108.4+/-55.0 g/L), cholesterol (76.3+/-16.7 vs 85.6+/-32.3, 96.1+/-38.7 mg/dL), and IGFBP1 (56.8+/-47.2 vs 89.7+/-50.3 ng/mL after 2 wk) were significantly increased compared to control group (P<0.05). However, serum GH was decreased. The increase of serum IGF1 and IGFBP3 after rhGH treatment was also observed. CONCLUSION: rhGH in combination with lactulose may be beneficial to the prevention and treatment of multiple organ dysfunction in patients with chronic severe hepatitis.

Adult↗
PubMed2005

Molecular and expression characterization of three gonadotropin subunits common alpha, FSHbeta and LHbeta in groupers.

A SMART cDNA plasmid library was constructed from protogyous greasy grouper (Epinephelus coioides) pituitary, and the full-length cDNAs of three gonadotropin (GTH) subunits common alpha, FSHbeta and LHbeta were cloned and sequenced from the library. The nucleotide sequences of common alpha, FSHbeta and LHbeta subunit cDNAs are 647, 594 and 574 bp in length, and encode for mature peptides of 94, 99 and 115 aa, respectively. High homology was observed by amino acid sequence alignment and identity comparison of the grouper mature peptides of common alpha, FSHbeta and LHbeta with that of other fishes. Phylogenetic tree analyses of the three GTH mature subunits revealed similar phylogeny relationships among the studied fish species. Three polyclonal antibodies were prepared from the in vitro expressed common alpha, FSHbeta and LHbeta mature proteins, respectively. Western blot analysis and immunofluoresence localization were performed on two typical stages of ovarian development stages in red-spotted grouper. Significant differences in protein expression levels of three gonadotropin subunits were revealed between the two ovarian development stages. In the individuals with resting ovary, common alpha was almost not detected in pituitaries, and FSHbeta and LHbeta expression levels were very low. While in the individuals with developing ovary, the expression of all three gonadotropin subunits reached to a high level. Immunofluoresence localization indicated that the grouper FSHbeta cells mainly distributed in the middle area of PPD, while the LHbeta cells distributed more widely, including in the area similar to the FSHbeta cells and at the external periphery of pituitary near to the PI side. The common alpha might be expressed in both FSHbeta and LHbeta cells. Double immunofluoresence localization further demonstrated FSHbeta and LHbeta expression in distinct cells in the PPD area, although the FSHbeta and LHbeta cells were detected in the identical area of PPD.

Amino Acid Sequence↗
PubMed2005

JIP1 regulates neuronal apoptosis in response to stress.

We examined if the relative expression of JNK-interacting protein 1 (JIP1) and phosphorylated c-Jun N-terminal kinase (JNK) regulates cell signaling and contributes to selective neuronal vulnerability in response to environmental stress. In clonal neuroblastoma cultures, stresses such as hypoxia, ischemia, Abeta peptides, and UV irradiation rapidly reduced JIP1 expression. JIP1 mRNA expression was also down-regulated by UV stress and was accompanied by increased JNK and c-Jun activation and cell death. JIP1 protein reduction was partially reversed both by inhibitors predominantly of caspase 3 and of the JNK pathway and resulted in significantly increased cell survival. Conversely, overexpression of JIP1 decreased both nuclear translocation of activated-JNK, and c-Jun phosphorylation induced by either UV irradiation, or the JNK upstream activators, MKK7 or MEKK1. Cell death was reduced about 50% compared to GFP-transfected controls. JIP1 overexpression did not facilitate either JNK expression or activation. In the normal, non-stressed human hippocampus and rat hippocampal organotypic cultures, JIP1 and JNK3 were inversely expressed with more JIP1 in CA2 and CA3 and less in CA1 neurons. In the human hippocampus, transient hypoxia/ischemia selectively spares neurons in CA2 and CA3 and induces death of neurons in the hippocampal CA1 subregion. In the cultures, ischemia reduced JIP1 expression and activated JNK, c-Jun, and caspase 3. Inhibitors of the JNK pathway, JNK activation directly and of caspase 3 activation each partially reversed these effects. Thus, under certain stress conditions, down-regulation of JIP1 expression makes neurons more susceptible to apoptosis, suggesting JIP may serve as an anti-apoptosis factor.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Characterization and purification of Saccharomyces cerevisiae RNase MRP reveals a new unique protein component.

In the yeast Saccharomyces cerevisiae, RNase mitochondrial RNA processing (MRP) is an essential endoribonuclease that consists of one RNA component and at least nine protein components. Characterization of the complex is complicated by the fact that eight of the known protein components are shared with a related endoribonuclease, RNase P. To fully characterize the RNase MRP complex, we purified it to apparent homogeneity in a highly active state using tandem affinity purification. In addition to the nine known protein components, both Rpr2 and a protein encoded by the essential gene YLR145w were present in our preparations of RNase MRP. Precipitation of a tagged version of Ylr145w brought with it the RNase MRP RNA, but not the RNase P RNA. A temperature-sensitive ylr145w mutant was generated and found to exhibit a rRNA processing defect identical to that seen in other RNase MRP mutants, whereas no defect in tRNA processing was observed. Homologues of the Ylr145w protein were found in most yeasts, fungi, and Arabidopsis. Based on this evidence, we propose that YLR145w encodes a novel protein component of RNase MRP, but not RNase P. We recommend that this gene be designated RMP1, for RNase MRP protein 1.

Amino Acid Sequence↗