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Zhou M, Yu K, Wang XH, Yang CS, Lei YP, Wang YG, Xue YZ, Yao HC, Gao B. Analysis on application timing of IABP in emergency PCI treatment of patients with combined acute myocardial infarction and cardiac shock. Eur Rev Med Pharmacol Sci 2017; 21:2934-2939. [PMID: 28682422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To study the application timing and effect of intra-aortic balloon pump (IABP) in the emergency PCI treatment of patients with combined acute myocardial infarction (AMI) and cardiogenic shock (CS). PATIENTS AND METHODS 84 cases of patients with combined AMI and CS under PCI in emergency treatment were randomly divided into the control group (n=42) and observational group (n=42). The control group underwent IABP again, after the invalidation of internal medicine drug treatment, while the observational group underwent IABP before the operation. We compared the effects of treatment. RESULTS After the intervention, the averages of arterial pressure and urine volume were increased in both groups than before (p <0.05). The average of heart rate was decreased, and the improvement in the observational group was more significant (p <0.05). However, the mortality rate in the observational group during the perioperative period was decreased than the control group as well as, the success rate of off-respirator was significant (p <0.05). The comparison of IABP complication occurrence rate as well as the survival rate after 1-year follow-up between both groups was not significantly different. Additionally, whereas the NYHA grouping in two groups was gradually improved, the difference was not statistically significant between both groups. However, in the observational group, the LVEF after one-month follow-up was significantly higher than in the control group (p <0.05), but not when comparing 1-year. VEDd at each time point in two groups were also similar. CONCLUSIONS The early IABP can improve hemodynamics of patients with combined AMI and CS under emergency PCI. It can reduce perioperative mortality rate, improve the success rate of off-respirator, but cannot increase IABP complication incidence rate while having little influence on the long-term survival rate and cardiac function indicator.
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Affiliation(s)
- M Zhou
- Department of Cardiology of Liaocheng People' Hospital, Donghangxi Road, Liaocheng, China.
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He WH, Zhu Y, Zhu Y, Liu P, Zeng H, Xia L, Huang X, Lei YP, Lü NH. [Comparison of severity and clinical outcomes between hypertriglyceridemic pancreatitis and acute pancreatitis due to other causes]. Zhonghua Yi Xue Za Zhi 2016; 96:2569-72. [PMID: 27596553 DOI: 10.3760/cma.j.issn.0376-2491.2016.32.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the difference in severity and clinical outcomes between hypertriglyceridemic pancreatitis (HTGP) and acute pancreatitis (AP) of other causes, and to analyze the correlation between the serum triglyceride (TG) level <24 h after onset and the disease severity. METHODS Patients were selected from the AP database of the First Affiliated Hospital of Nanchang University, who were admitted between January 2005 and December 2013, aged ≥18 and ≤85 years, excluding pregnant or lactating women. Severity and etiology of AP were classified according to the latest relevant guidelines. The severity and clinical outcomes of HTGP patients (HTGP group) were compared with those of patients with AP of other causes (non-HTGP group). Among the HTGP patients, those admitted within 24 hours of onset were selected for comparison of serum TG levels on the first day of hospitalization day among patients with mild, moderate, and severe HTGP, and the correlation between the serum TG level and the severity was analyzed. RESULTS Altogether 3 558 AP patients were selected, of which 623 (17.5%) were HTGP, and 2 935 (82.5%)were non-HTGP patients. Compared with the non-HTGP group, the HTGP group had higher incidence of pancreatic necrosis (28.3% vs 18.1%), infected pancreatic necrosis (6.1% vs 3.7%), organ failure(35.8% vs 29.1%), and persistent organ failure(24.4% vs 16.5%), with all the differences being statistically significant (all P<0.01). The mortality and average stay in intensive care unit were also higher in the HTGP group than in the non-HTGP group (all P<0.05). There were 291 patients with HTGP who were admitted to hospital within 24 hours of onset. The serum TG levels <24 h after onset were (9.38±9.00) mmol/L, (11.90±9.02) mmol/L, and (16.47±11.75) mmol/L in patients with mild, moderate, and severe HTGP, respectively (P<0.01). Spearman's correlation analysis showed a positive correlation between TG level <24 h after onset and disease severity (r=0.26, P<0.01). CONCLUSIONS Compared with AP of other causes, HTGP patients have more severe clinical course and worse clinical outcomes. The serum TG level within 24 hours of onset may be positively correlated with the severity of HTGP.
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Affiliation(s)
- W H He
- Department of Gastroenterology, First Affiliated Hospital of Nanchang University, Nanchang 330006, China
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Zhou XD, Chen HX, Guan RN, Lei YP, Shu X, Zhu Y, Lv NH. Protein kinase B phosphorylation correlates with vascular endothelial growth factor A and microvessel density in gastric adenocarcinoma. J Int Med Res 2013; 40:2124-34. [PMID: 23321169 DOI: 10.1177/030006051204000610] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVE The signalling molecule protein kinase B (Akt) modulates many cellular processes. Phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathways play important roles in tumour angiogenesis. The aim of this study was to determine the role of phosphorylated Akt (pAkt) in angiogenesis and its correlation with vascular endothelial growth factor (VEGF)-A in gastric adenocarcinoma. METHODS Tumour tissue and matched healthy gastric mucosa were obtained from patients undergoing surgical resection of gastric adenocarcinoma. Akt and pAkt were detected via Western blotting. VEGF-A, pAkt and CD34 were examined by immunohistochemistry. RESULTS Akt and pAkt protein levels were significantly higher in gastric cancer tissue than in normal tissue (n = 48 patients). Positive VEGF-A immunostaining was significantly associated with pAkt immunostaining. Microvessel density was correlated with both VEGF-A and pAkt positivity. CONCLUSIONS Phosphorylated Akt and VEGF-A are involved in angiogenesis of gastric adenocarcinoma, and Akt activation may contribute to angiogenesis via VEGF-A upregulation. The PI3K/Akt/VEGF signalling pathway may be involved in gastric adeno carcinoma.
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Affiliation(s)
- X D Zhou
- Department of Gastroenterology, First Affiliated Hospital of Nanchang University, Nanchang, China
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Ma QG, Gao X, Zhou T, Zhao LH, Fan Y, Li XY, Lei YP, Ji C, Zhang JY. Protective effect of Bacillus subtilis ANSB060 on egg quality, biochemical and histopathological changes in layers exposed to aflatoxin B1. Poult Sci 2012; 91:2852-7. [PMID: 23091142 DOI: 10.3382/ps.2012-02474] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis ANSB060 from the fish gut had strong ability to detoxify aflatoxins. The aim of this research was to investigate the protective effect of B. subtilis ANSB060 (ANSB060) on egg quality and biochemical and histopathological changes of liver and kidney in laying hens when exposed to aflatoxin B(1). Treatments (C20, C40, and C60) were prepared by substituting corn contaminated by aflatoxin B(1) (AFB1) at different proportions (20, 40, and 60%) for normal corn in basic diets. The aflatoxin degradation enzyme (E) treatments (E20, E40, and E60) were mixed with the fermentation liquor of ANSB060 with C20, C40, and C60, respectively. The results showed that ANSB060 can improve the eggshell strength in E60 compared with C60 (P ≤ 0.05), and toxin reduced the content of total protein (in groups C20, C40, and C60) and albumin (in C20 and C40; P < 0.05) and heightened the activities of GPT (in C60) and GOT (in C40 and C60) in serum (P < 0.05). In the liver, AFB1 inhibited the activity of superoxide dismutase and glutathione peroxidase (C40 and C60; P < 0.05) and increased the content of malonaldehyde (in C40 and C60), which induced the damage in the liver and kidney as shown in the photomicrographs of hematoxylin and eosin-stained sections. The addition of ANSB060 can enhance the activity of antioxidant enzymes, and it recovered the protein synthesis in liver. Moreover, ANSB060 also ameliorated the damage of liver and kidney tissue and restored them to normal. Hence, ANSB060 had the ability to inhibit the damage induced by AFB1; it will have a great potential in industrial applications.
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Affiliation(s)
- Q G Ma
- College of Animal Science and Technology, China Agricultural University, Beijing, China
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Zhao LH, Guan S, Gao X, Ma QG, Lei YP, Bai XM, Ji C. Preparation, purification and characteristics of an aflatoxin degradation enzyme from Myxococcus fulvus ANSM068. J Appl Microbiol 2010; 110:147-55. [PMID: 21040271 DOI: 10.1111/j.1365-2672.2010.04867.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS To prepare, purify and characterize an extracellular enzyme from Myxococcus fulvus ANSM068, designated as myxobacteria aflatoxin degradation enzyme (MADE), which possesses degradation activity against aflatoxin B(1) (AFB(1) ), G(1) (AFG(1) ) and M(1) (AFM(1) ) in solution. METHODS AND RESULTS The culture supernatant of strain M. fulvus demonstrated high degradation ability against AFB(1) (71·89%), AFG(1) (68·13%) and AFM(1) (63·82%) after 48 h of incubation. An enzyme was purified from the supernatant of M. fulvus using ethanol precipitation and chromatography on DEAE-Sepharose and Superdex 75. An overall 166-fold purification of the enzyme with a recovery of 57% and a final specific activity of 569·44 × 10(3) U mg(-1) was obtained using the present purification protocol. The apparent molecular mass of MADE was estimated to be 32 kDa by SDS-PAGE. AFG(1) and AFM(1) were significantly degraded, by 96·96 and 95·80%, respectively, when treated with pure MADE (100 U ml(-1) ) produced by strain ANSM068. MADE exhibited the largest amount of activity at 35°C and pH 6·0, with Mg(2+) ions greatly promoting and Zn(2+) strongly inhibiting MADE activity. CONCLUSIONS An aflatoxin DEGRADATION ENZYME FROM BACTERIAL ISOLATES CAN EFFECTIVELY REMOVE AFLATOXIN B(1) , G(1) AND M(1) IN SOLUTION. SIGNIFICANCE AND IMPACT OF THE STUDY The high activity and wide temperature and pH range of MADE for the degradation of aflatoxin have promising applications in control of mycotoxins during food and feed processing.
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Affiliation(s)
- L H Zhao
- National Laboratory of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, China
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Abstract
Polymorphism of HLA-DPB1 was revealed with a sequencing-based typing (SBT) method in 47 unrelated healthy individuals from Yunnan Hani ethnic minority. The alleles DPB1*5901 and DPB1*7001 were detected for the first time in Chinese populations. A dendrogram showed that the Hani ethnic group belongs to the southern group of Chinese.
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Affiliation(s)
- W-H Hu
- Key Laboratory of Bioresources Conservation and Utilization & Human Genetics Center, Yunnan University, Kunming, Yunnan 650091, China
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Wen X, Lei YP, Zhou YL, Okamoto CT, Snead ML, Paine ML. Structural organization and cellular localization of tuftelin-interacting protein 11 (TFIP11). Cell Mol Life Sci 2005; 62:1038-46. [PMID: 15868102 DOI: 10.1007/s00018-005-4547-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Tuftelin-interacting protein (TFIP11) was first identified in a yeast two-hybrid screening as a protein interacting with tuftelin. The ubiquitous expression of TFIP11 suggested that it might have other functions in non-dental tissues. TFIP11 contains a G-patch, a protein domain believed to be involved in RNA binding. Using a green fluorescence protein tag, TFIP11 was found to locate in a novel subnuclear structure that we refer to as the TFIP body. An in vivo splicing assay demonstrated that TFIP11 is a novel splicing factor. TFIP11 diffuses from the TFIP body following RNase A treatment, suggesting that the retention of TFIP11 is RNA dependent. RNA polymerase II inhibitor (-amanitin and actinomycin D) treatment causes enlargement in size and decrease in number of TFIP bodies, suggesting that TFIP bodies perform a storage function rather than an active splicing function. The TFIP body may therefore represent a new subnuclear storage compartment for splicing components.
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Affiliation(s)
- X Wen
- Center for Craniofacial Molecular Biology, University of Southern California School of Dentistry, 2250 Alcazar Street, CSA room 103, Los Angeles, California, 90033-1004, USA
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Hu WH, Lu J, Lei YP, Chen BW, Tang WR, Cun YN, Dong YL, Tan SJ, Yu HJ, Xiao CJ. HLA-DPB1 allelic frequency of the Lisu ethnic group in the Southwest China and evolutionary relationship of Lisu with other populations. ACTA ACUST UNITED AC 2005; 65:289-92. [PMID: 15730526 DOI: 10.1111/j.1399-0039.2005.00361.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A sequencing-based typing of human leukocyte antigen-DPB1 (HLA-DPB1) gene was carried out in 37 unrelated healthy individuals from the Yunnan Lisu ethnic minority. A total of 12 DPB1 alleles, in which DPB1*1301 (33.3%), DPB1*0402 (16.6%), DPB1*040101 (13.8%), and DPB1*0501 (11.1%) were highly predominant, were found, and allele DPB1*200102 was found for the first time in a Chinese population. A dendrogram constructed by neighbor-joining method showed that the Lisu ethnic group belongs to East Asian cluster.
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Affiliation(s)
- W-H Hu
- Human Genetics Center, Key Laboratory of Bioresources Conservation and Utilization Yunnan University, Kunming, Yunnan, PR China
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Snead ML, Paine ML, Chen LS, Luo BY, Zhou DH, Lei YP, Liu YH, Maxson RE. The murine amelogenin promoter: developmentally regulated expression in transgenic animals. Connect Tissue Res 2001; 35:41-7. [PMID: 9084642 DOI: 10.3109/03008209609029173] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We are interested in understanding hierarchical regulation pathways that control gene expression in developing teeth. In pursuit of the molecular basis for the regulated expression of amelogenin by developing ameloblasts during tooth formation, we isolated the murine amelogenin promoter. Analysis of this promoter will provide additional details towards the identification of signals generated through instructive-, dissimilar-germ layer interactions that are for responsible for temporal- and spatial-regulation for amelogenin gene expression. Using transgenic mice we demonstrate that a 2263 nucleotide stretch of the murine amelogenin promoter conveys appropriate temporal- and spatial-regulation for amelogenin gene expression in response to instructive-signals. These transgenic animals are useful reagents to further dissect signaling pathways responsible for regulated gene expression by terminally differentiated ameloblasts.
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Affiliation(s)
- M L Snead
- Center for Craniofacial Molecular Biology, School of Dentistry, University of Southern California, Los Angeles 90033, USA.
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Snead ML, Paine ML, Luo W, Zhu DH, Yoshida B, Lei YP, Paine CT, Chen LS, Burstein JM, Jitpukdeebudintra S, White SN, Bringas P. Transgene animal model for protein expression and accumulation into forming enamel. Connect Tissue Res 2001; 38:279-86; discussion 295-303. [PMID: 11063035 DOI: 10.3109/03008209809017048] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Understanding the cellular and molecular events that regulate the formation of enamel is a major driving force in efforts to characterize critical events during amelogenesis. It is anticipated that through such an understanding, improvements in prevention, diagnosis and treatment-intervention into heritable and acquired diseases of enamel could be achieved. While knowledge of the precise role of an enamel-specific protein in directing the formation of inorganic crystallites remains refractory, progress has been made with other aspects of amelogenesis that can be brought to bear on the subject. One such area of progress has been with the identification of an ameloblast-lineage specific amelogenin gene promoter. This promoter can be used to direct the expression of enamel-specific proteins, as well as the expression of proteins foreign to amelogenesis, into the enamel extracellular matrix where their effect on biomineralization can be ascertained in a prospective manner. The resulting enamel from such animals can be examined by morphologic and biochemical modalities in order to identify the effect of the transgene protein on enamel crystallite formation and subsequent biomineralization. This manuscript outlines such a strategy with the potential for enhancing our understanding of amelogenesis.
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Affiliation(s)
- M L Snead
- The Center for Cranirofacial Molecular Biology, The University of Southern California, Los Angeles 90033, USA
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Paine ML, Zhu DH, Luo W, Bringas P, Goldberg M, White SN, Lei YP, Sarikaya M, Fong HK, Snead ML. Enamel biomineralization defects result from alterations to amelogenin self-assembly. J Struct Biol 2000; 132:191-200. [PMID: 11243888 DOI: 10.1006/jsbi.2000.4324] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Enamel formation is a powerful model for the study of biomineralization. A key feature common to all biomineralizing systems is their dependency upon the biosynthesis of an extracellular organic matrix that is competent to direct the formation of the subsequent mineral phase. The major organic component of forming mouse enamel is the 180-amino-acid amelogenin protein (M180), whose ability to undergo self-assembly is believed to contribute to biomineralization of vertebrate enamel. Two recently defined domains (A and B) within amelogenin appear essential for this self-assembly. The significance of these two domains has been demonstrated previously by the yeast two-hybrid system, atomic force microscopy, and dynamic light scattering. Transgenic animals were used to test the hypothesis that the self-assembly domains identified with in vitro model systems also operate in vivo. Transgenic animals bearing either a domain-A-deleted or domain-B-deleted amelogenin transgene expressed the altered amelogenin exclusively in ameloblasts. This altered amelogenin participates in the formation an organic enamel extracellular matrix and, in turn, this matrix is defective in its ability to direct enamel mineralization. At the nanoscale level, the forming matrix adjacent to the secretory face of the ameloblast shows alteration in the size of the amelogenin nanospheres for either transgenic animal line. At the mesoscale level of enamel structural hierarchy, 6-week-old enamel exhibits defects in enamel rod organization due to perturbed organization of the precursor organic matrix. These studies reflect the critical dependency of amelogenin self-assembly in forming a competent enamel organic matrix and that alterations to the matrix are reflected as defects in the structural organization of enamel.
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Affiliation(s)
- M L Paine
- University of Southern California, School of Dentistry, Center for Craniofacial Molecular Biology, 2250 Alcazar Street, CSA Room 142, Los Angeles, California 90033-1004, USA.
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Moradian-Oldak J, Paine ML, Lei YP, Fincham AG, Snead ML. Self-assembly properties of recombinant engineered amelogenin proteins analyzed by dynamic light scattering and atomic force microscopy. J Struct Biol 2000; 131:27-37. [PMID: 10945967 DOI: 10.1006/jsbi.2000.4237] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dynamic light scattering (DLS) analysis together with atomic force microscopy (AFM) imaging was applied to investigate the supramolecular self-assembly properties of a series of recombinant amelogenins. The overall objective was to ascertain the contribution of certain structural motifs in amelogenin to protein-protein interactions during the self-assembly process. Mouse amelogenins lacking either amino- or carboxy-terminal domains believed to be involved in self-assembly and amelogenins having single or double amino acid mutations identical to those found in cases of amelogenesis imperfecta were analyzed. The polyhistidine-containingfull-length recombinant amelogenin protein [rp(H)M180] generated nanospheres with monodisperse size distribution (hydrodynamic radius of 20.7 +/- 2.9 nm estimated from DLS and 16.1 +/- 3.4 nm estimated from AFM images), comparable to nanospheres formed by full-length amelogenin rM179 without the polyhistidine domain, indicating that this histidine modification did not interfere with the self-assembly process. Deletion of the N-terminal self-assembly domain from amelogenin and their substitution by a FLAG epitope ("A"-domain deletion) resulted in the formation of assemblies with a heterogeneous size distribution with the hydrodynamic radii of particles ranging from 3 to 38 nm. A time-dependent dynamic light scattering analysis of amelogenin molecules lacking amino acids 157 through 173 and containing a hemagglutinin epitope ("B"-domain deletion) resulted in the formation of particles (21.5 +/- 6.8 nm) that fused to form larger particles of 49.3 +/- 4.3 nm within an hour. Single and double point mutations in the N-terminal region resulted in the formation of larger and more heterogeneous nanospheres. The above data suggest that while the N-terminal A-domain is involved in the molecular interactions for the formation of nanospheres, the carboxy-terminal B-domain contributes to the stability and homogeneity of the nanospheres, preventing their fusion to larger assemblies. These in vitro findings support the notion that the proteolytic cleavage of amelogenin at amino- and carboxy-terminii occurring during enamel formation influences amelogenin to amelogenin interactions during self-assembly and hence alters the structural organization of the developing enamel extracellular matrix, thus affecting enamel biomineralization.
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Affiliation(s)
- J Moradian-Oldak
- Center for Craniofacial Molecular Biology, School of Dentistry, University of Southern California, California, Los Angeles 90033, USA
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Abstract
DSC was used to study the ability of glass-forming sugars to affect the gel-to-fluid phase transition temperature, T(m), of several phosphatidylcholines during dehydration. In the absence of sugars, T(m) increased as the lipid dried. Sugars diminished this increase, an effect we explain using the osmotic and volumetric properties of sugars. Sugars vitrifying around fluid phase lipids lowered T(m) below the transition temperature of the fully hydrated lipid, T(o). The extent to which T(m) was lowered below T(o) ranged from 12 degrees to 57 degrees, depending on the lipids' acyl chain composition. Sugars vitrifying around gel phase lipids raised T(m) during the first heating scan in the calorimeter, then lowered it below T(o) in subsequent scans of the sample. Ultrasound measurements of the mechanical properties of a typical sugar-glass indicate that it is sufficiently rigid to hinder the lipid gel-to-fluid transition. The effects of vitrification on T(m) are explained using the two-dimensional Clausius-Clapeyron equation to model the mechanical stress in the lipid bilayer imposed by the glassy matrix. Dextran and polyvinylpyrrolidone (PVP) also vitrified but did not depress T(m) during drying. Hydration data suggest that the large molecular volumes of these polymers caused their exclusion from the interbilayer space during drying.
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Affiliation(s)
- K L Koster
- Department of Biology, University of South Dakota, Vermillion, South Dakota 57069, USA.
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Lei YP. [Treatment of recurrent aphtha ulcer with placenta fluid: Clinical evaluation]. Shanghai Kou Qiang Yi Xue 1993; 2:192-3. [PMID: 15159799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Affiliation(s)
- Y P Lei
- Department of Beizhan Hospital. Shanghai 200005,China
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Sun SD, Luo Y, Zhao XW, Lei YP, Zhang Q, Ding JF. [Effects of microinjection of clonidine into nucleus tractus solitarii on atrial natriuretic factor in rats]. Sheng Li Xue Bao 1991; 43:400-4. [PMID: 1836674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In order to study whether atrial natriuretic factor (ANF) is involved in the depressor effect of clonidine, microinjection of the latter into nucleus tractus solitarii (NTS) was carried out in anesthetized stroke-prone spontaneously hypertensive rats (SHRsp) and normotensive Wistar-Kyoto (WKY) rats. Each strain was randomly divided into three groups by injecting: (1) clonidine (1.0 microgram/0.2 microliter); (2) yohimbine (3.3 micrograms/0.2 microliter) followed by (1); (3) artificial cerebral spinal fluid (ACSF, 0.2 microliter) as control. A decrease of blood pressure and heart rate and a suppression of ANF release elicited by clonidine were significantly greater in SHRsp than in WKY rats. After blockade of alpha 2-receptor with yohimbine, the hypotensive effect of clonidine was blocked completely in WKY rats, but only partially in SHRsp, while the suppression effect on ANF release was eliminated in both strains. In addition, the decrease of plasma catecholamine produced by clonidine could also be blocked after yohimbine. The results suggest that ANF probably does not contribute to the depressor effect of centrally administered clonidine, while in SHRsp the decrease of plasma ANF might be a blood pressure-dependent compensatory response.
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Affiliation(s)
- S D Sun
- Cardiovascular Institute, Chinese Academy of Medical Sciences, Beijing
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Liu LS, Zhao Y, Lei YP, Wang W, Zhang XE, Jin L. Calcium antagonists in prevention of hypertension and stroke in stroke-prone spontaneously hypertensive rats. Chin Med J (Engl) 1989; 102:106-13. [PMID: 2505975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
To investigate the effect of Calcium antagonists (Ca-An) with different tissue specificity in the development of hypertension and stroke in salt-loading SHRSP, three experiments were conducted. In experiment I (1), 50 8-week-old male SHRSP were divided into three groups and given nifedipine (NF, 32 mg/kg/day), menidipine (MN 32 mg/kg/day) and placebo (control group) respectively. In the control group 83.3% (15/18) died of stroke and 17 showed renal vascular sclerosis. Their average lifespan was 84 days. NF and MN significantly reduced systolic blood pressure (SBP), and no stroke of renal vascular sclerosis developed. In experiment I (2), 54 7-week-old male SHRSP were divided into three groups (18 in each group). They were treated with nimodipine (NM) 20 mg/kg/day, 2 mg/kg/day and placebo respectively. NM (20 mg/kg/day) markedly lowered SBP and postponed the onset of stroke. Only 11% died in 17 weeks. NM (2 mg/kg/day did not lower SBP but postpond the onset of stroke. In experiment II (1), 29 10-week-old female SHRSP were divided into three groups: Group A was given NF 32 mg/kg/day, group B was parathyroidectomized (PTX) and group C served as control. PTX group did not lower SBP but could postpone the onset of stroke. In experiment II (2), 33 male SHRSP were divided into three groups and ticated as described above in experiment II (1) (11 in each group). Seven weeks after the experiment, the brain blood flow of NF group was significantly greater (67.5%) than that of the control and PTX groups. In experiment III, 27 7-week-old male SHRSP were divided into three groups as described above in experiment I (2).(ABSTRACT TRUNCATED AT 250 WORDS)
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