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Enterococcus faecalis Extracellular Vesicles Promote Apical Periodontitis. J Dent Res 2024; 103:672-682. [PMID: 38679731 DOI: 10.1177/00220345241230867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2024] Open
Abstract
Enterococcus faecalis is an important contributor to the persistence of chronic apical periodontitis. However, the mechanism by which E. faecalis infection in the root canals and dentinal tubules affects periapical tissue remains unclear. Bacterial extracellular vesicles (EVs) act as natural carriers of microbe-associated molecular patterns (MAMPs) and have recently attracted considerable attention. In this study, we investigated the role of EVs derived from E. faecalis in the pathogenesis of apical periodontitis. We observed that E. faecalis EVs can induce inflammatory bone destruction in the periapical areas of mice. Double-labeling immunofluorescence indicated that M1 macrophage infiltration was increased by E. faecalis EVs in apical lesions. Moreover, in vitro experiments demonstrated the internalization of E. faecalis EVs into macrophages. Macrophages tended to polarize toward the M1 profile after treatment with E. faecalis EVs. Pattern recognition receptors (PRRs) can recognize MAMPs of bacterial EVs and, in turn, trigger inflammatory responses. Thus, we performed further mechanistic exploration, which showed that E. faecalis EVs considerably increased the expression of NOD2, a cytoplasmic PRR, and that inhibition of NOD2 markedly reduced macrophage M1 polarization induced by E. faecalis EVs. RIPK2 ubiquitination is a major downstream of NOD2. We also observed increased RIPK2 ubiquitination in macrophages treated with E. faecalis EVs, and E. faecalis EV-induced macrophage M1 polarization was notably alleviated by the RIPK2 ubiquitination inhibitor. Our study revealed the potential for EVs to be considered a virulence factor of E. faecalis and found that E. faecalis EVs can promote macrophage M1 polarization via NOD2/RIPK2 signaling. To our knowledge, this is the first report to investigate apical periodontitis development from the perspective of bacterial vesicles and demonstrate the role and mechanism of E. faecalis EVs in macrophage polarization. This study expands our understanding of the pathogenic mechanism of E. faecalis and provides novel insights into the pathogenesis of apical periodontitis.
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[Investigation of the chronic respiratory symptoms and pulmonary function of adult residents in Hongtong County, Shanxi Province]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2023; 57:1571-1580. [PMID: 37859373 DOI: 10.3760/cma.j.cn112150-20221107-01075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Objective: To investigate the chronic respiratory symptoms and pulmonary function of adult residents in 3 towns of Hongtong County, Shanxi Province, and to explore their risk factors. Methods: The investigation of chronic respiratory symptoms and lung function status of adult residents in Hongdong County is based on the regional population of the entire county in Hongdong County. The project was initiated by the Science and Technology Department of Linfen City and coordinated by the Hongdong County Government. The investigation will be conducted in 3 townships in Hongdong County, Linfen City, Shanxi Province from April to November 2021: Demographic characteristics, respiratory symptoms, smoking dust exposure and other personal history were collected through questionnaires. Physical examination, routine blood tests and lung function tests were also performed on each individual. SPSS 22.0 software was used to conduct t test, χ2 test, ANOVA or Kruskal-Wallis test for statistical analysis of the collected information. Results: 10 945 subjects aged 18-102 years were included in the analysis, of whom 3 754 (34.3%) were male, 1 222 (11.2%) had a history of dust exposure, 7 164 (65.5%) had used straw and firewood as cooking fuel, and 3 296 (30.1%) had a history of smoking. Among the participants, 394 (3.6%), 339 (3.1%), and 1 543 (14.1%) had respiratory symptoms such as chronic cough, sputum, and dyspnea. Statistics showed that the population with chronic respiratory symptoms was more elderly and had a smoking history, and the incidence of chronic respiratory symptoms was higher in those who smoked more than 40 packs a year (all P<0.05). Men with a history of dust exposure were more likely to suffer from chronic cough and expectoration, while emaciation and biofuel use for more than 40 years were more likely to suffer from chronic expectoration and dyspnea (all P<0.05). The median values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC in 1 second were 2.19 L/s, 3.24 L and 69.16%, respectively. Among them, the lung function of 5 801 (53.0%) respondents was lower than the expected value. The median FEV1/FVC decreased with the increase of age. The FEV1/FVC of people over 40 years old with smoking history was lower, the dust exposure history of people with decreased lung function was more than that of people with normal lung function, and the incidence of chronic expectoration and dyspnea was higher in people with decreased lung function (all P<0.05). The absolute value and ratio of eosinophils in patients with decreased ventilation function over 60 years old were significantly higher than those with normal ventilation function, but the level of body mass index (BMI) was lower (all P<0.05). Conclusion: In Hongdong County, Shanxi Province, grassroots residents have poor medical awareness, low lung function examination rate, chronic respiratory symptoms and lung function decline are associated with more risk factors. Primary medical institutions need to formulate prevention strategies and carry out lung function detection according to the actual situation, focusing on monitoring and follow-up of high-risk groups to achieve early and timely prevention, diagnosis and treatment of chronic obstructive pulmonary disease.
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[Development of a risk assessment scale and test of its validity and reliability for venous thromboembolism in adult burn patients]. ZHONGHUA SHAO SHANG YU CHUANG MIAN XIU FU ZA ZHI 2022; 38:778-787. [PMID: 36058701 DOI: 10.3760/cma.j.cn501120-20210322-00098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To develop a venous thromboembolism (VTE) risk assessment scale for adult burn patients and to test its reliability and validity. Methods: The scale research method and multi-center cross-sectional survey method were used. Based on the results of literature analysis method and brain-storming method, the letter questionnaire for experts was formulated. Then 27 experts (9 doctors of burn department, 9 vascular surgeons, and 9 nurses) were performed with two rounds of correspondences by Delphi method, and the reliability of the experts was analyzed. The weight of each item was determined by optimal sequence diagram method and expert importance evaluation to form the VTE Risk Assessment Scale for Adult Burn Patients. A total of 223 adult burn inpatients, who were admitted to 5 tier Ⅲ grade A general hospitals including the Affiliated Hospital of Southwest Medical University, West China Hospital of Sichuan University, the Affiliated Hospital of North Sichuan Medical College, Nanchong Central Hospital, and the Second People's Hospital of Yibin City from October 1st 2019 to January 1st 2020, were selected as respondents by convenience sampling method. The first assessment was performed with the VTE Risk Assessment Scale for Adult Burn Patients within 24 hours of admission of patients, and real-time assessment was performed as the patients' condition and treatment changed. The highest value was taken as the result. Correlation coefficient method and critical ratio method were used for item analysis; Cronbach's α coefficient was used to test the internal consistency of scale; content validity index was used to analyze the content validity of the scale, and receiver's operating characteristic (ROC) curve was drawn to test the predictive validity of the scale. Data were statistically analyzed with chi-square test, Pearson correlation analysis, independent sample t test, and Z test. Results: As four questionnaires in the first round of correspondence were rejected as unqualified, and another 4 experts were selected for the 2 rounds of correspondence. Most of them were aged 41 to 50 years with postgraduate degrees, engaging in the current profession for 11 to 30 years, and all of them had professional titles of associate senior or above. The scale, constructed through literature analysis, group brainstorming, and two rounds of correspondence, includes 3 primary items and 50 secondary items. In the first round of correspondence, the recovery rate of valid questionnaires and the ratio with expert opinions were 85.2% (23/27) and 47.8% (11/23), respectively. In the second round of correspondence, the recovery rate of valid questionnaires and the ratio with expert opinions were 100% (27/27) and 11.1% (3/27), respectively. The average collective authority coefficients of experts were both 0.90 in the 2 rounds of correspondence. The mean values of importance assignment, full score rate, and selection rate above 4 were 4.21, 52.5%, and 77.2%, respectively, in the first round of correspondence, and 4.28, 45.2%, and 85.8%, respectively, in the second round of correspondence. The mean coefficients of variation and the mean value of Kendall's coefficient of harmony for each item were 0.21 and 0.30 in the first round of correspondence, respectively, and 0.16 and 0.36 in the second round of correspondence, respectively. In the first and second rounds of correspondence, the Kendall's coefficients of harmony of 3 primary items (age and underlying diseases, burn injury factors, and burn treatment factors) and total secondary items were statistically significant (with χ2 values of 121.46, 107.09, 116.00, 331.97, 169.97, 152.12, 141.54, and 471.70, P<0.01). The weights of primary items for age and underlying diseases, burn injury factors, and burn treatment factors were 0.04, 0.05, and 0.07, respectively. The weights of secondary items ranged from 0.71 to 0.99, with assigned values of 3 to 6. The total burn area of 223 patients ranged from 1% to 89% total body surface area, and the patients were aged from 19 to 96 years, with the risk assessment score from 0 to 98. Nine patients developed VTE, with a risk assessment score of 41 to 90. The scores of 37 items were significantly positively correlated with the total score of scale (with r values of 0.14 to 0.61, P<0.05 or P<0.01), and the items were retained. There were 36 secondary items with statistically significant differences between the patients in high-score group and low-score group (with Z values of -4.88 to -2.09, t values of -11.63 to -2.09, P<0.05 or P<0.01), and the items were retained. The total Cronbach's α coefficient of scale was 0.88. The total content validity index of scale was 0.95. The optimal threshold of the scale for the diagnosis of VTE was 40, at which the sensitivity was 88.9%, the specificity was 87.4%, the Youden index was 0.87, and the area under the ROC curve was 0.96 (with 95% confidence interval of 0.93 to 0.99, P<0.01). Conclusions: The age and underlying diseases, burn injury factors, and burn treatment factors are the risk factors for VTE in adult burn patients. The VTE risk assessment scale for adult burn patients developed based on these factors has good reliability and validity, and provide good reference value for clinical VTE risk assessment.
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In-situ synchrotron X-ray diffraction data for the dynamic reaction processes between titanium and air under laser irradiation. Data Brief 2020; 29:105155. [PMID: 32368575 PMCID: PMC7187328 DOI: 10.1016/j.dib.2020.105155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/05/2020] [Accepted: 01/13/2020] [Indexed: 11/27/2022] Open
Abstract
This article presents data related to the research article entitled "Diffusion of oxygen and nitrogen into titanium under laser irradiation in air" [1]. When irradiated with varying laser parameters under ambient air, titanium surfaces are observed to exhibit differing colors. To better understand this phenomenon, the dynamic reaction steps between titanium and air under laser irradiation were investigated with in-situ synchrotron X-ray diffraction method. With a programmed laser profile, a set of diffraction patterns were collected by a 2D detector and then analyzed with the program FIT2D. Based on the data, the detailed high-temperature reactions between titanium and air during laser irradiation were clearly revealed. The presented raw in-situ synchrotron X-ray diffraction data can be reused for the further insights of laser surface modification of titanium in air, or for discovering the optimal laser conditions for industrial decoration or medical applications of titanium.
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Genetic Mapping of a Major Resistance Gene to Pea Aphid (Acyrthosipon pisum) in the Model Legume Medicago truncatula. Int J Mol Sci 2016; 17:E1224. [PMID: 27483247 PMCID: PMC5000622 DOI: 10.3390/ijms17081224] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 01/05/2023] Open
Abstract
Resistance to the Australian pea aphid (PA; Acyrthosiphon pisum) biotype in cultivar Jester of the model legume Medicago truncatula is mediated by a single dominant gene and is phloem-mediated. The genetic map position for this resistance gene, APR (Acyrthosiphon pisum resistance), is provided and shows that APR maps 39 centiMorgans (cM) distal of the A. kondoi resistance (AKR) locus, which mediates resistance to a closely related species of the same genus bluegreen aphid (A. kondoi). The APR region on chromosome 3 is dense in classical nucleotide binding site leucine-rich repeats (NLRs) and overlaps with the region harbouring the RAP1 gene which confers resistance to a European PA biotype in the accession Jemalong A17. Further screening of a core collection of M. truncatula accessions identified seven lines with strong resistance to PA. Allelism experiments showed that the single dominant resistance to PA in M. truncatula accessions SA10481 and SA1516 are allelic to SA10733, the donor of the APR locus in cultivar Jester. While it remains unclear whether there are multiple PA resistance genes in an R-gene cluster or the resistance loci identified in the other M. truncatula accessions are allelic to APR, the introgression of APR into current M. truncatula cultivars will provide more durable resistance to PA.
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Advancing multiscale structural mapping of the brain through fluorescence imaging and analysis across length scales. Interface Focus 2016; 6:20150081. [PMID: 26855758 DOI: 10.1098/rsfs.2015.0081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Brain function emerges from hierarchical neuronal structure that spans orders of magnitude in length scale, from the nanometre-scale organization of synaptic proteins to the macroscopic wiring of neuronal circuits. Because the synaptic electrochemical signal transmission that drives brain function ultimately relies on the organization of neuronal circuits, understanding brain function requires an understanding of the principles that determine hierarchical neuronal structure in living or intact organisms. Recent advances in fluorescence imaging now enable quantitative characterization of neuronal structure across length scales, ranging from single-molecule localization using super-resolution imaging to whole-brain imaging using light-sheet microscopy on cleared samples. These tools, together with correlative electron microscopy and magnetic resonance imaging at the nanoscopic and macroscopic scales, respectively, now facilitate our ability to probe brain structure across its full range of length scales with cellular and molecular specificity. As these imaging datasets become increasingly accessible to researchers, novel statistical and computational frameworks will play an increasing role in efforts to relate hierarchical brain structure to its function. In this perspective, we discuss several prominent experimental advances that are ushering in a new era of quantitative fluorescence-based imaging in neuroscience along with novel computational and statistical strategies that are helping to distil our understanding of complex brain structure.
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Cloning and characterization of the SERK1 gene in triploid Pingyi Tiancha [Malus hupehensis (Pamp.) Rehd. var. pingyiensis Jiang] and a tetraploid hybrid strain. GENETICS AND MOLECULAR RESEARCH 2015; 14:14576-86. [PMID: 26600517 DOI: 10.4238/2015.november.18.21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This study aims to explore the roles of somatic embryogenesis receptor-like kinase (SERK) in Malus hupehensis (Pingyi Tiancha). The full-length sequences of SERK1 in triploid Pingyi Tiancha (3n) and a tetraploid hybrid strain 33# (4n) were cloned, sequenced, and designated as MhSERK1 and MhdSERK1, respectively. Multiple alignments of amino acid sequences were conducted to identify similarity between MhSERK1 and MhdSERK1 and SERK sequences in other species, and a neighbor-joining phylogenetic tree was constructed to elucidate their phylogenetic relations. Expression levels of MhSERK1 and MhdSERK1 in different tissues and developmental stages were investigated using quantitative real-time PCR. The coding sequence lengths of MhSERK1 and MhdSERK1 were 1899 bp (encoding 632 amino acids) and 1881 bp (encoding 626 amino acids), respectively. Sequence analysis demonstrated that MhSERK1 and MhdSERK1 display high similarity to SERKs in other species, with a conserved intron/exon structure that is unique to members of the SERK family. Additionally, the phylogenetic tree showed that MhSERK1 and MhdSERK1 clustered with orange CitSERK (93%). Furthermore, MhSERK1 and MhdSERK1 were mainly expressed in the reproductive organs, in particular the ovary. Their expression levels were highest in young flowers and they differed among different tissues and organs. Our results suggest that MhSERK1 and MhdSERK1 are related to plant reproduction, and that MhSERK1 is related to apomixis in triploid Pingyi Tiancha.
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Characterization and genetic dissection of resistance to spotted alfalfa aphid (Therioaphis trifolii) in Medicago truncatula. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:5157-72. [PMID: 24058162 PMCID: PMC3830491 DOI: 10.1093/jxb/ert305] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Aphids cause significant yield losses in agricultural crops worldwide. Medicago truncatula, a model legume, cultivated pasture species in Australia and close relative of alfalfa (Medicago sativa), was used to study the defence response against Therioaphis trifolii f. maculate [spotted alfalfa aphid (SAA)]. Aphid performance and plant damage were compared among three accessions. A20 is highly susceptible, A17 has moderate resistance, and Jester is strongly resistant. Subsequent analyses using A17 and A20, reciprocal F1s and an A17×A20 recombinant inbred line (RIL) population revealed that this moderate resistance is phloem mediated and involves antibiosis and tolerance but not antixenosis. Electrical penetration graph analysis also identified a novel waveform termed extended potential drop, which occurred following SAA infestation of M. truncatula. Genetic dissection using the RIL population revealed three quantitative trait loci on chromosomes 3, 6, and 7 involved in distinct modes of aphid defence including antibiosis and tolerance. An antibiosis locus resides on linkage group 3 (LG3) and is derived from A17, whereas a plant tolerance and antibiosis locus resides on LG6 and is derived from A20, which exhibits strong temporary tolerance. The loci identified reside in regions harbouring classical resistance genes, and introgression of these loci in current medic cultivars may help provide durable resistance to SAA, while elucidation of their molecular mechanisms may provide valuable insight into other aphid-plant interactions.
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Identification of distinct quantitative trait loci associated with defence against the closely related aphids Acyrthosiphon pisum and A. kondoi in Medicago truncatula. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:3913-22. [PMID: 22442407 PMCID: PMC3388833 DOI: 10.1093/jxb/ers084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Aphids are a major family of plant insect pests. Medicago truncatula and Acyrthosiphon pisum (pea aphid, PA) are model species with a suite of resources available to help dissect the mechanism underlying plant-aphid interactions. A previous study focused on monogenic and relatively strong resistance in M. truncatula to PA and other aphid species. In this study a moderate resistance to PA was characterized in detail in the M. truncatula line A17 and compared with the highly susceptible line A20 and the more resistant line Jester. The results show that PA resistance in A17 involves both antibiosis and tolerance, and that resistance is phloem based. Quantitative trait locus (QTL) analysis using a recombinant inbred line (RIL) population (n=114) from a cross between A17 and A20 revealed that one locus, which co-segregated with AIN (Acyrthosiphon-induced necrosis) on chromosome 3, is responsible for the reduction of aphid biomass (indicator of antibiosis) for both PA and bluegreen aphid (BGA, A. kondoi), albeit to a lesser degree for PA than BGA. Interestingly, two independent loci on chromosomes 5 and 3 were identified for the plant biomass reduction (indicator of plant tolerance) by PA and BGA, respectively, demonstrating that the plant's tolerance response to these two closely related aphid species is distinct. Together with previously identified major resistant (R) genes, the QTLs identified in this study are powerful tools to understand fully the spectrum of plant defence against sap-sucking insects and provide opportunities for breeders to generate effective and sustainable strategies for aphid control.
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Relationship between serum hepatitis B virus DNA and surface antigen with covalently closed circular DNA in HBeAg-negative patients. J Med Virol 2010; 82:1494-500. [PMID: 20648602 DOI: 10.1002/jmv.21863] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is responsible for viral persistence. This study aimed to investigate the serum surrogate markers for cccDNA and to evaluate the intrahepatic viral events associated with disease activity in HBeAg-negative chronic hepatitis B patients. Thirty-three treatment-naïve patients with a negative HBeAg who had a liver biopsy were studied. Active disease was defined as a serum alanine aminotransferase >40 IU/L and a serum HBV DNA >10,000 copies/ml. This study showed significant correlation between serum HBV DNA and both log cccDNA (r = 0.41, P = 0.018) and log total intrahepatic HBV DNA (r = 0.71, P < 0.0001). No significant correlation was observed between serum HBsAg and log cccDNA (P = 0.15) or log total intrahepatic HBV DNA (P = 0.97). Fourteen and 19 patients had inactive and active disease, respectively. The median log cccDNA and log total intrahepatic HBV DNA (copies/10(6) cells) were significantly higher in patients with active disease compared with those with inactive disease (4.11 vs. 3.53, P = 0.03 and 5.46 vs. 4.64, P < 0.001, respectively). The HBV replicative efficiency, defined as the ratio of serum HBV DNA to cccDNA, was approximately 20% higher in patients with active disease. No significant difference was observed in the HBsAg levels and the ratio of serum HBsAg to cccDNA between the two groups. In conclusion, serum HBV DNA, but not HBsAg, reflects the amount of cccDNA and the replication efficiency of HBV in patients with HBeAg-negative chronic hepatitis B.
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Significant histopathology in Chinese chronic hepatitis B patients with persistently high-normal alanine aminotransferase. J Viral Hepat 2010; 17 Suppl 1:44-50. [PMID: 20586933 DOI: 10.1111/j.1365-2893.2010.01270.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Current guidelines recommend antiviral therapy for chronic hepatitis B (CHB) patients with elevated alanine aminotransferase (ALT) and high viral load. Scant histological data exist for CHB patients with persistently normal ALT (PNALT) because disease progression is thought to be rare. To identify potential predictors of significant histology in the presence of PNALT, we compared the clinical characteristics and histology of Chinese CHB PNALT patients to those in patients with elevated ALT. Percutaneous liver biopsy was performed in 522 CHB patients with Chinese ethnicity who had not had antiviral treatment. Differences in age, ALT, viral load, hepatitis B e antigen (HBeAg) status and liver histology were compared between eligible PNALT (252) and elevated ALT (270) patients. Of the PNALT patients, 38.5% had normal liver histology, 25.4% had significant necroinflammation and/or fibrosis and 8.4% had established cirrhosis. Furthermore, histopathological differences between patients with high-normal ALT (0.5-1.0 x the upper limit of normal (ULN)) and low-normal ALT (≤ 0.5 x ULN) were evaluated. There was a significantly greater prevalence of histopathology in the high-normal group (40.0%) than in the low-normal group (16.6%) (P < 0.001). Multiple logistic regression identified that significant histopathology findings in PNALT patients correlated with age (P < 0.001) and ALT level (P < 0.001), with age >40 years and ALT >0.5 x ULN predicting significant histopathology. Our data indicate that liver biopsy is recommended in CHB patients >40 years of age, particularly when their ALT is 0.5-1.0 x ULN. The findings above provide evidence for indication of antiviral therapy in patients with PNALT and significant histopathological change.
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[The analysis of differential expression and cloning of genes related to raised secondary lateral veins mutant of Lycoris aurea]. YI CHUAN = HEREDITAS 2007; 29:490-8. [PMID: 17548314 DOI: 10.1360/yc-007-0490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Lycoris aurea exhibits parallel venation, the main vein with many lateral veins in a longitudinal parallel arrangement. There are secondary lateral veins (SLV) between each longitudinal veins. In general, SLVs are not remarkable. In this paper, the material was one kind of Lycoris aurea mutant called Raised Secondary Lateral Veins mutant (RSLV), because many Raised Secondary Lateral Veins are in abaxial surface of its leaves. Its growing potential is weaker than that of wild type and its blades are very thin. Moreover, the stamens of RSLV degenerate completely. Two cDNA libraries were constructed from RSLV mutant and wild type (WT) leaves. From the libraries, 3,122 ESTs, which are longer than 100 bp each after vector sequence removed, were acquired by single-pass sequencing from the 5'end. Following a multistep selection, 512 70-mer oligo-DNA probes were designed for attachment on the microarray slide based on the ESTs. The gene expression profile of RSLV mutant and WT leaves was compared through the microarray at transcriptional level. The microarray experiment results were further confirmed by Quantitative Real-Time PCR (QRT-PCR). We identified 5 genes whose expressions changed more than 2-fold between RSLV mutant and WT leaves. They encode phloem protein 2 (PP2), ferritin, pectin methyl esterase (PME), chlorophyll a/b binding protein (CAB protein) and pyruvate decarboxylase (PDC), respectively. Furthermore, the full-length cDNA sequences of the 5 genes were separately obtained from RSLV and WT by RACE. The relationship between differential expressions of the genes and the formation of the RSLV mutant phenotype were discussed.
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Effect of Ga and Mn doping on structural, electrical transport and magnetic properties of Na(0.75)CoO(2). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2006; 18:4381-4388. [PMID: 21690789 DOI: 10.1088/0953-8984/18/17/023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The effects of doping with magnetic Mn ions or nonmagnetic Ga ions on the structural, electrical transport and magnetic properties of Na(0.75)CoO(2) have been investigated. It has been found that the lattice parameter c of the samples increases with Ga or Mn ion doping. Ga doping raises the electrical resistivity of Na(0.75)CoO(2), but the metallic conducting behaviour of the compound has not been influenced. In contrast, 5% Mn doping leads to a metal-insulator transition at low temperatures in Na(0.75)Co(1-y)Mn(y)O(2). The susceptibility of the Ga doped sample shows strong magnetic field dependence, while the susceptibility of the Mn doped samples is not very sensitive to the magnetic field. This work implies that magnetic interaction plays an important role in Na(x)CoO(2).
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The variation of heat transfer coefficient, adiabatic effectiveness and aerodynamic loss with film cooling hole shape. Ann N Y Acad Sci 2001; 934:361-8. [PMID: 11460648 DOI: 10.1111/j.1749-6632.2001.tb05871.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The heat transfer coefficient and adiabatic effectiveness of cylindrical, fan shaped holes and a slot are presented for the region zero to 50 diameters downstream of the holes. Narrow-band liquid crystals were used on a heated flat plate with heated air coolant. These parameters have been measured in a steady state, low speed facility at engine representative Reynolds number based on hole diameter and pressure difference ratio (ideal momentum flux ratio). The aerodynamic loss due to each of the film cooling geometries has been measured using a traverse of the boundary layer far downstream of the film cooling holes. Compared to the cylindrical holes, the fan shaped hole case showed an improvement in the uniformity of cooling downstream of the holes and in the level of laterally averaged film cooling effectiveness. The fan effectiveness approached the slot level and both the fan and cylindrical hole cases show lower heat transfer coefficients than the slot and non film cooled cases based on the laterally averaged results. The drawback to the fan shaped hole was that the aerodynamic loss was significantly higher than both the slot and cylindrical hole values due to inefficient diffusion in the hole exit expansion.
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[Establishment and its application of a reporter-based screening model for discovering new ligands of estrogen receptor alpha subtypes]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2000; 35:747-51. [PMID: 11372440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
AIM To establish a sensitive and efficient reporter gene based screening model and use it to screen compounds for discovering new ligands of estrogen receptor alpha subtype. METHODS A recombinant Epstein-Barr virus episomal vector (pMT/ERE-CAT) was constructed by inserting a synthetic sequence composed of five estrogen response elements upstream of promoter and a chloramphenicol acetyltransferase (CAT) gene downstream of promoter. pMT/ERE-CAT was transfected into HepG2 cells expressing estrogen receptor alpha subtype (ER +HepG2). Hygromycin (200 micrograms.mL-1) was added 48 h after transfection for selection. One stably transfected clone was isolated and used to screen compounds for activity of stimulating CAT gene expression using colorimetric CAT assay. RESULTS In the ER +HepG2 cells, the expression of CAT gene was induced by estradiol. A dose-dependent expression of CAT gene with half-maximal induction at 0.07 nmol.L-1 was observed. The ER +HepG2 cell was used to screen compounds for activity of stimulating CAT gene expression. Resveratrol was found to produce a maximal level of induction (1.75 times of estradiol). In vitro radiation survival experiment showed that the radioprotection activity of resveratrol (D0 = 3.18 Gy) is stronger than that of estradiol (D0 = 2.59 Gy). CONCLUSION Vector pMT/ERE-CAT was used to generate stably transfected ER +HepG2 cell lines. The cell lines can be used to screen compounds for estrogen activity by testing extracts of cells grown in microtiter wells directly using colorimetric CAT assay. This system should provide an efficient method for screening and analyzing the activity of large numbers of ligands of estrogen receptor.
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Abstract
It has recently been shown that a Chinese traditional medicine, kurorinone, extracted from Sophora Flavescens Ait, possesses antiviral properties. We evaluated the efficacy and safety of kurorinone treatment in patients with chronic hepatitis B. Ninety-four patients with abnormal alanine transaminase (ALT) levels and hepatitis B e antigen (HBeAg) and/or hepatitis B virus (HBV) DNA-positivity were randomly assigned to receive either kurorinone 400 mg daily (45 patients) or 3 million units (MU) of interferon-alpha (IFN-alpha) (49 patients, daily for 1 month, every other day for 2 months) for 3 months. Patients were followed-up for 12 months. At baseline, both groups were comparable regarding age, gender and serological parameters. At the end of treatment, complete response (defined as ALT normalization and HBeAg and/or HBV DNA loss) occurred in 50% of the kurorinone group and in 61.3% of the IFN-alpha-treated group (P > NS). At the end of the 12-month follow-up period, a complete response (sustained response) occurred in 26.7-36.7% of kurorinone-treated patients with moderate or mild liver damage and in 44.4-46.7% of IFN-alpha-treated patients with similar liver injury. In kurorinone- as well as in IFN-alpha-treated patients, there was no statistical significant difference with respect to complete response rates between HBeAg-positive and hepatitis B e antibody-positive subgroups. Kurorinone had no untoward side-effects except for local pain at injection sites. The results of this trial suggest that kurorinone is able to inhibit HBV replication and improve disease remission in patients with chronic hepatitis B.
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Effects of sex hormones on action potential and contraction of guinea pig papillary muscle. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1998; 19:248-50. [PMID: 10375736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
AIM To study the effects of sex hormones, estradiol (Est), progesterone (Pro) and testosterone (Tes) on the action potential (AP) and contraction of guinea pig papillary muscle. METHODS Using conventional glass microelectrode and mechanical recording of myocardial contraction. RESULTS Est slowed down the maximal rate of rise of phase 0 (Vmax) of AP at low concentration (1 mumol.L-1). At 10 mumol.L-1 and above, Est also prolonged AP duration (APD50 and APD90), effective refractory period (ERP) and decreased the maximal isometric tension (Pmax) and velocity of tension development (dT/dt) of contraction. Tes (100 mumol.L-1 - 1 mmol.L-1) prolonged APD90 and ERP with decreased Pmax and dT/dt. But Pro (1 mumol.L-1 - 1 mmol.L-1) had no effects on both AP and contraction. CONCLUSION Est prolonged AP and depressed contraction of guinea pig papillary muscle.
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Effects of sodium pentobarbital on electric and mechanical activities of guinea pig papillary muscle. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1996; 17:439-41. [PMID: 9863169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
AIM To study the effects of sodium pentobarbital (SP) on the action potential (AP) and contraction of guinea pig papillary muscle. METHODS Using conventional glass microelectrode and mechanical recording of myocardium contraction. RESULTS SP (> or = 10 mumol.L-1) prolonged the AP duration (APD) and effective refractory period (ERP), while amplitude (APA) and Vmax of phase 0 showed no changes. The effects of SP were abolished by pretreatment with cromakalim, an agonist of ATP-sensitive K+ channel. The maximal isometric tension (Pmax) and velocity of tension development (dT/dt) were decreased to 51% and 48% of control, respectively. The first postrest beat (B1) and second postrest beat (B2) were also depressed. CONCLUSION SP affected the action potential by reducing activities of the K+ channels and reduced the contraction of guinea pig myocardium.
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Abstract
Serial data from studies of infants at the University of Iowa and from the Fels Longitudinal Study were used to develop sex-specific percentiles for increments in weight and recumbent length for selected intervals during the first 24 months of life. Weight increments are presented for 1-month intervals from birth to 6 months, 2-month intervals from birth to 12 months, and 3-month intervals from birth to 24 months. Length increments are presented for 2-month intervals from birth to 6 months, and for 3-month intervals from birth to 24 months of age. Weights and lengths at the target ages were obtained for the Iowa data by simple interpolation, and for the Fels data by fitting families of three-parameter mathematical functions to the serial data from ages 1 to 24 months. The tabular presentations are based on the Iowa data from birth to 3 months of age, on the combined Iowa and Fels data from 3 to 6 months of age, and on the Fels data from 6 to 24 months of age. We believe that these reference data will be useful in screening for deviations from normal growth and may aid in early detection of failure to thrive or excessive weight gain during early life.
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Patterns of change in weight/stature2 from 2 to 18 years: findings from long-term serial data for children in the Fels longitudinal growth study. Int J Obes (Lond) 1991; 15:479-85. [PMID: 1845371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Serial weight/stature2 (W/S2) data recorded semi-annually from 2 to 18 years in the Fels longitudinal study were analyzed to establish an approach for the investigation of long-term serial changes in body fatness during childhood and adolescence in individuals. To describe patterns of change in body fatness during childhood and adolescence, a family of mathematical models was fitted to individual serial W/S2 data recorded from 250 boys and 246 girls. The selected models fitted the W/S2 data well as judged by the root mean square errors. Based on the fitted models, variables representing patterns of change in an individual were derived. These included estimated value of W/S2 at 2 years of age (W/S(2)2yr), minimum value of W/S2 (W/S2min), age at minimum value of W/S2 (Amin), maximum velocity of W/S (Vmax), age at maximum velocity of W/S2 (AVmax), maximum value of W/S2 (W/S2max), and age at maximum value of W/S2 (Amax). There were highly significant correlations between observed W/S2 at 18 years and all the derived variables except AVmax indicating, for example, that in both sexes about 25 percent of the variation in W/S2 at 18 years could be explained by when Amin occurs or by the value of W/S2min. The negative correlations (r = -0.5) between Amin and W/S2 at 18 years suggested that the earlier children reach their nadir in W/S2, the earlier they began to increase in adiposity and the fatter they were at 18 years. Likewise, the positive correlations (r approximately 0.3 and 0.5, respectively) between the W/S(2)2yr or W/S2min and W/S2 at 18 years indicated that increased childhood adiposity may lead to increased adult adiposity.
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Monthly growth status from a longitudinal study of Canadian infants. CANADIAN JOURNAL OF PUBLIC HEALTH = REVUE CANADIENNE DE SANTE PUBLIQUE 1990; 81:215-21. [PMID: 2361209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Reference data for weight, recumbent length and head circumference at 1-month intervals from 1 through 18 months have been developed from measurements of 351 healthy infants born at term in Montreal or Toronto. Each infant was measured serially from 1 to 18 months. A 3-parameter mathematical model was fitted to the serial data for each infant. The model fitted the serial data well for almost all the infants as evaluated by the residual mean square errors. Subsequently, values were estimated for each month of age from 1 through 18 months for each infant. These estimated values allowed the development of reference data that have been presented in tables and in graphs.
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Capillary blood gases in the neonate. A reassessment and review of the literature. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1990; 144:168-72. [PMID: 2105629 DOI: 10.1001/archpedi.1990.02150260046025] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Heel puncture capillary blood gas (CBG) measurements continue to be used in neonates for estimating arterial blood gas values. Review of the literature reveals general agreement that CBG PO2 values are of little use in predicting arterial PO2 and that CBG pH values are reliable predictors of arterial pH; opinion varies regarding CBG PCO2. We conducted a two-part study comparing postductal arterial and CBG values. First, 50 infants were studied, each only once. All infants had umbilical arterial catheters in place. Blood was obtained simultaneously from the umbilical artery catheter and the warmed heels. Results demonstrated poor predictability of arterial values from CBG pH and PCO2 as well as for PO2. Second, to determine if variation both within and among individuals was similar, repeated measurements were made in 27 additional infants comparable to the first group. We obtained 3 to 28 simultaneous postductal arterial and CBG samples from each infant. A random-effects nested analysis of variance indicated that for pH, variation was largely the result of between-subject or within-subject replicates effects, while for PO2 and PCO2, most variation was explained by differences between the two techniques (umbilical artery catheter vs CBG). The results indicate that CBG measurements do not accurately predict arterial values in neonates. Extreme caution should be used when management decisions are based on CBG values.
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Fat-free mass in children and young adults predicted from bioelectric impedance and anthropometric variables. Am J Clin Nutr 1989; 50:435-43. [PMID: 2773822 DOI: 10.1093/ajcn/50.3.435] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Fat-free mass (FFM) values calculated from densitometry by using a multicomponent model were significantly (p less than 0.05) larger than those from the Siri two-component model (465 males, 441 females), especially in children and females. The multicomponent model assumes the density of FFM varies by age and sex because of differences in its constituents. With FFM values from the multicomponent model as the dependent variable and impedance and anthropometry as the independent variables, prediction equations were derived by all possible subsets of regression (140 males, 110 females). These equations had RMSEs of 2.2-2.3 kg and CVs of 5.0-5.8%. Cross-validation results were excellent for young adults but less satisfactory for children for whom a different calf skinfold had been measured. The selected equations are applicable to healthy white individuals aged 7-25 y.
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Head circumference reference data: birth to 18 years. Pediatrics 1987; 79:706-12. [PMID: 3575026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Highly reliable data from a sample of 888 white US children, measured serially in a single study, have been used to provide reference data for head circumference from birth to 18 years of age. The present data differ little from those already available for the age range from birth to 36 months of age, but they are considerably higher (about 0.5 cm) at older ages for boys and tend to be slightly higher for girls. These new reference data are smoother across age than those used currently for screening and evaluation. Percentiles for 6-month increments from birth to 6 years have been provided.
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Doubling time of human chorionic gonadotropin (hCG) in early normal pregnancy: relationship to hCG concentration and gestational age. Fertil Steril 1987; 47:584-9. [PMID: 2436952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
There is controversy regarding whether the doubling time of human chorionic gonadotropin (hCG) in early normal pregnancy is constant or rises with increasing gestational age (GA) and hCG concentration. To clarify the influence of these variables on hCG doubling time, we obtained serial blood specimens every 2 to 4 days between postovulatory day 12 and 70 from 16 women who conceived while monitoring basal body temperature. The serum concentration of beta-hCG was determined by radioimmunoassay. Serial doubling time of hCG was calculated in all subjects and correlated with GA and hCG concentration. Least-squares estimates of 95% confidence bands were established from regression analysis given the second hCG concentration for each pair of samples or GA. For elimination of the need for calculation and thus improvement of the clinical utility of doubling time determinations, a nomogram relating the concentrations of hCG in paired serum samples to doubling time was constructed. We observed a significant correlation of doubling time with hCG concentration and GA, both in the group overall and within each individual pregnancy. These data support the recommendation that doubling time determinations should be evaluated with reference to normal values for a given GA or hCG concentration and suggest that previously proposed normal values of doubling time in early normal pregnancy may be low.
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Body composition predictions from bioelectric impedance. Hum Biol 1987; 59:221-33. [PMID: 3596563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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The influence of physiologic variables and oral contraceptives on bioelectric impedance. Hum Biol 1987; 59:257-69. [PMID: 3596566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Bioelectric impedance measures of body composition: their relationship with level of blood pressure in young adults. Hum Biol 1987; 59:245-55. [PMID: 3596565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Head circumference growth patterns: birth to 18 years. Hum Biol 1986; 58:893-906. [PMID: 3557415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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[Morphological observations on the elastic fibers in 3 cases of elastofibroma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1986; 15:230-1. [PMID: 2953468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Quantitative structure-activity relationship of the mutagenicity of substituted N-nitroso-N-benzylmethylamines: possible implications for carcinogenicity. J Med Chem 1986; 29:40-4. [PMID: 3510299 DOI: 10.1021/jm00151a006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The relative mutagenicities of substituted N-nitroso-N-benzylmethylamines have been reexamined from a quantitative structure-activity relationship point of view. Most of the compounds were mutagenic toward Salmonella typhimurium TA 1535 with Aroclor-induced male hamster liver S9 activation. The dose-response data were subjected to a multiple linear regression equation calculated in a stepwise manner, which found that the differences in mutagenicities could be explained primarily by differences in the three-bond path molecular connectivity index, with smaller contributions from sigma and pi. Moreover, a polynomial regression analysis showed that the maximum mutagenicity could be explained by an optimal amount of electron withdrawal by the substituent which would cause a weakening, or activation, of the methylene C-H bond. The possible relevance of these observations to carcinogenesis is discussed.
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[Pathologic observation on 21 cases of subcutaneous nodule of paragonimiasis in the Mudanjiang Region]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1985; 14:46-8. [PMID: 2935278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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[Pharmacological actions of dehydrocorydaline on cardiovascular system (author's transl)]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1982; 17:61-5. [PMID: 7090829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Radioimmunoassay for mouse nerve growth factor (NGF). Effects of thyroxine administration on tissue NGF levels. Brain Res 1980; 186:331-41. [PMID: 7357457 DOI: 10.1016/0006-8993(80)90979-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A sensitive and specific radioimmunoassay (RIA) has been developed for beta-nerve growth factor (NGF) purified from the submaxillary gland of the adult male mouse. The RIA is sensitive to 13 pg/assay tube with an intra-assay coefficient of variation of 7% and an interassay coefficient of variation of 11.8%. Of the substances tested for immunological cross-reactivity in the RIA, only mouse epidermal growth factor caused significant displacement of the radiolabeled ligand; 11% at a dose of 10 microgram/ml. Mouse tissue extracts diluted out parallel to the standard curve. The effects of altered thyroid function on tissue NGF concentration in adult male mice were studied using the RIA. Thyroxine administration (25 microgram T4 i.p. daily for 12 days) caused significant increases in submaxilllary gland and liver NGF content and concentration (P less than 0.001) compared to controls but had no significant effect on heart and kidney NGF levels. Propylthiouracil treatment (0.05% PTU in the drinking water for 21 days) led to a marked increase in thyroid gland weight (550% of control) but had no significant effect on NGF concentration in any of the organs studied with the exception of kidney where a 75% reduction in NGF concentration was observed. These studies indicate that thyroid hormones increase NGF content and concentration in the submaxillary gland and liver of adult male mice and are suggestive of increased NGF synthesis. Thyroid hormones may therefore play an important regulatory role in NGF metabolism in peripheral tissues of the adult mouse.
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Abstract
The effects of thyroxine and propylthiouracil on nerve growth factor concentrations in cerebral cortex, cerebellum, and brainstem of adult male mice were assessed by using a sensitive radioimmunoassay for the beta-subunit of mouse nerve growth factor. Thyroxine administration significantly increased the concentration of nerve growth factor in all three brain areas compared to control values, whereas propylthiouracil was without effect. These results suggest that thyroid hormones stimulate nerve growth factor synthesis in the mature central nervous system, and raise the possibility that the influence of thyroid hormones on central nervous system development might be mediated or influenced by nerve growth factor.
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Effect of thiamine deprivation and thiamine antagonists on the level of gamma-aminobutyric acid and on 2-oxoglutarate metabolism in rat brain. J Neurochem 1974; 22:831-6. [PMID: 4407102 DOI: 10.1111/j.1471-4159.1974.tb04301.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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