1
|
A porcine alveolar macrophage cell line stably expressing CD163 demonstrates virus replication and cytokine secretion characteristics similar to primary alveolar macrophages following PRRSV infection. Vet Microbiol 2020; 244:108690. [PMID: 32402349 DOI: 10.1016/j.vetmic.2020.108690] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 04/04/2020] [Accepted: 04/10/2020] [Indexed: 11/30/2022]
Abstract
The in vitro investigation of cytokine secretion induced by porcine reproductive and respiratory syndrome virus (PRRSV) requires porcine alveolar macrophages (PAMs) and their interaction with immunocytes. However, immortalized monoclonal PAMs (mPAMs) are non-permissive for PRRSV infection. The porcine CD163 receptor isolated from primary PAMs (pPAMs) confers susceptibility to PRRSV infection; thus, this approach could be used to establish a novel cell line to facilitate the exploration of PRRSV infection kinetics. Here, we amplified the coding region of the CD163 gene from pPAMs and integrated it into an mPAM line using a lentivirus expression system. After verification, the monoclonal PAM cell line stably expressing CD163 (mPAM-CD163-GFP) was infected with either the highly pathogenic PRRSV strain JXA1 or the classical PRRSV strain SD1, which produced high infectious titers of progeny virus reaching > 109 copies/mL or a 50 % tissue culture infective dose of 105.5 over at least 100 cell generations. We also investigated cytokine and Toll-like receptor expression in infected mPAM-CD163-GFP cells and pPAMs. The mPAM-CD163-GFP cell line showed similar patterns of viral replication and cytokine secretion compared with pPAMs, so it may be extremely useful for replacing primary cells for in vitro investigations of the mechanisms of cytokine secretion and interactions between PRRSV-infected PAMs and immunocytes.
Collapse
|
2
|
Decreased synovial fluid pituitary adenylate cyclase-activating polypeptide (PACAP) levels may reflect disease severity in post-traumatic knee osteoarthritis after anterior cruciate ligament injury. Peptides 2019; 116:22-29. [PMID: 31039374 DOI: 10.1016/j.peptides.2019.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 04/08/2019] [Accepted: 04/10/2019] [Indexed: 11/25/2022]
Abstract
BACKGROUND It has been demonstrated that anterior cruciate ligament (ACL) injury-induced cartilage degeneration is the key risk factor for post-traumatic knee osteoarthritis (PTKOA).Pituitary adenylate cyclase-activating polypeptide (PACAP), a common neuropeptide exerting a wide spectrum of functions, has been proved to inhibit inflammation and prevent cartilage degeneration. OBJECTIVE The current study was performed to investigate circulating and synovial fluid PACAP concentrations in ACL injury patients to determine their relationship with the disease progression of the severity of post-traumatic knee osteoarthritis (PTKOA). METHODS 72 ACL injury patients receiving arthroscopical examination and surgery were enrolled in the study. Meanwhile, 60 gender-and-age non-traumatic patellar dislocation patients were enrolled as controls. The VAS score, Lysholm Score and International Knee Documentation Committee (IKDC) score were all recorded to evaluate the clinical severity. Serum and synovial fluid (SF) PACAP levels were investigated by enzyme-linked immunosorbent assay (ELISA).The IL-1β and TNF-α levels were also investigated. The degree of meniscus injury was assessed by MR imaging. The modified Mankin score was recorded to examine the cartilage histopathological alternations. Receiver operating characteristic (ROC) curve was performed to discuss the diagnostic value of PACAP levels for the prediction of the radiographic grading in comparison with IL-1β and TNF-α. RESULTS Serum PACAP levels between PTKOA patients and patellar dislocation did not reach significant differences. However, SF PACAP levels were significantly lower in PTKOA patients than controls. In addition, SF PACAP levels were negatively associated with MRI imaging grade for meniscus injury and VAS score, and were positively associated with Lysholm and IKDC scores. In addition, SF PACAP levels were negatively related to Mankin score as well as the expressions of IL-1β and TNF-α. ROC analysis curve showed that attenuated PACAP may serve as a favorable marker for the diagnosis of MRI for meniscus injury. CONCLUSIONS SF PACAP concentrations showed an independent and negative association with disease severity in PTKOA following ACL injury. Local treatment with PACAP may act as a possible adjuvant therapy for delaying the process of PTKOA.
Collapse
|
3
|
The synovial fluid neuropeptide PACAP may act as a protective factor during disease progression of primary knee osteoarthritis and is increased following hyaluronic acid injection. Innate Immun 2019; 25:255-264. [PMID: 30935267 PMCID: PMC6830887 DOI: 10.1177/1753425919839125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 02/25/2019] [Accepted: 02/28/2019] [Indexed: 11/15/2022] Open
Abstract
The correlation of serum and synovial fluid (SF) pituitary adenylate cyclase-activating polypeptide (PACAP) levels with disease progression of primary knee osteoarthritis (OA) was explored. Radiographic severity of OA was determined by Kellgren-Lawrence (K-L) grades. PACAP levels were measured by ELISA before treatment, and 4 and 8 wk following hyaluronic acid (HA) injection. Levels of IL-1β and MMP-3 were also detected. The numeric pain scale (NPS), revised Oxford Knee Score (OKS), and American Knee Society Score (AKSS) were employed to evaluate to symptomatic severity. Receiver-operating-characteristic (ROC) curve analysis was carried out to compare the diagnostic value of PACAP, IL-1β, and MMP-3 for the K-L grade. PACAP concentrations in SF but not serum were significantly lower in OA patients compared with controls. SF PACAP levels were negatively associated with K-L grades and higher NPS as well as worse AKSS and OKS. Further analysis demonstrated that PACAP concentration in SF was negatively correlated with expressions of IL-1β as well as MMP-3 and may act as a marker for radiographic progression along with MMP-3. Last, we found SF PACAP levels exhibited an incremental trend after HA injection. These findings confirmed the crucial role of PACAP deficiency in the development of primary knee OA.
Collapse
|
4
|
Cryopreservation of gemmae of Marchantia polymorpha L. (Marchantiophyta, Marchantiaceae) without prior pretreatment. CRYO LETTERS 2015; 36:91-96. [PMID: 26017297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND Successful cryopreservation of gametophytic material of bryophytes requires pretreatment with sucrose or abscisic acid. Compared to gametophyte materials, spore and gemmae cryopreservation may be more efficient, simple and stable systems for storing large amounts of genetic diversity of bryophytes within a small space. However, there has still been no attempt at cryopreserving bryophyte gemmae. OBJECTIVE The aim of this study is to determine whether bryophyte gemmae with differing levels of desiccation tolerance could survive and germinate after cryopreservation without prior encapsulation and pretreatment. MATERIALS AND METHODS Gemmae of Marchantia polymorpha L. were dried with silica gel for different times and then rapidly cooled in liquid nitrogen. RESULTS The germination level of fresh gemmae was 95 % After 3 h predrying and 1 d in LN, germination was 68 % and was still up to 59 % after storage for 75 days. CONCLUSION We conclude that the natural desiccation tolerance of bryophyte gemmae permits cryopreservation without prior pretreatment other than drying.
Collapse
|
5
|
|
6
|
Enzyme replacement therapy for mucopolysaccharidosis VI (Maroteaux-Lamy syndrome): experience in Hong Kong. Hong Kong Med J 2011; 17:317-324. [PMID: 21813902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
Mucopolysaccharidosis VI (Maroteaux-Lamy syndrome) is a very rare inherited lysosomal storage disease. We evaluated the efficacy and safety of weekly infusions of recombinant human arylsulfatase B as enzyme replacement therapy for two patients in whom this condition was advanced. The primary outcome variables were the distance walked in a 6-minute walk test, forced vital capacity, and ejection fraction. The secondary outcome variables were the number of stairs climbed in a 3-minute stair climbing test, joint mobility, urinary glycosaminoglycan excretion, auto-continuous positive airway pressure study and liver size. After 24 weeks of treatment, patient A walked 40 m (36%) and patient B walked 66 m (58%) more in the walk test than at baseline. After 48 weeks, in patient A the corresponding improvements were 142 m (129%) in the walk test and 33 stairs (60%) in the 3-minute stair climbing test, and in patient B the respective improvements were 198 m (174%) and 77 stairs (140%). There was a significant decline in urinary glycosaminoglycan excretion and improvement in range of motion of joints in both patients. The auto-continuous positive airway pressure study revealed improvements in patient A, while other efficacy variables remained static. There were no drug-related adverse events or allergic reactions reported during and after the infusions of recombinant human arylsulfatase B. Recombinant human arylsulfatase B significantly improves endurance and reduces urinary glycosaminoglycan excretion. The drug is generally safe and well tolerated.
Collapse
|
7
|
Polycyclic aromatic hydrocarbons in leaf cuticles and inner tissues of six species of trees in urban Beijing. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2008; 151:158-64. [PMID: 17400349 DOI: 10.1016/j.envpol.2007.02.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 02/11/2007] [Accepted: 02/13/2007] [Indexed: 05/14/2023]
Abstract
Leaf samples of six tree species were collected along urban roadsides and a campus site in Beijing for measurement of polycyclic aromatic hydrocarbons (PAHs). PAHs in leaves were attributed to two fractions, leaf cuticles and inner leaf tissues, using sequential extraction. Total concentrations of 16 PAHs in the cuticles and the inner tissues were 69.3+/-64.6 microg g(-1) (d.w.) and 1.07+/-0.2 microg g(-1) (d.w.) at roadside and 57.5+/-52.6 microg g(-1) and 0.716+/-0.2 microg g(-1) on campus, respectively. The lipid-normalized inner tissue PAHs varied from 5.8 microg g(-1) to 15.0 microg g(-1). Similarities in PAH spectra between leaf cuticles and airborne particles and between the inner tissues and gaseous phase imply that airborne particulates and gaseous PAHs are likely the sources of PAHs for cuticles and the inner tissues, respectively. Difficulty in migration of heavier PAHs into inner tissues could be another reason.
Collapse
|
8
|
Particle size distributions of polycyclic aromatic hydrocarbons in rural and urban atmosphere of Tianjin, China. CHEMOSPHERE 2006; 62:357-67. [PMID: 15982711 DOI: 10.1016/j.chemosphere.2005.04.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2005] [Revised: 04/05/2005] [Accepted: 04/18/2005] [Indexed: 05/03/2023]
Abstract
The size distributions of 16 polycyclic aromatic hydrocarbons (PAHs) and particle mass less than 10 microm in aerodynamic diameter (Dp) were measured using a nine-stage low-volume cascade impactor at rural and urban sites in Tianjin, China in the winter of 2003-2004. The particles exhibited the trimodal distribution with the major peaks occurring at 0.43-2.1 and 9.0-10.0 microm for both urban and rural sites. The concentrations of the total PAH (sum of 16 PAH compound) at rural site were generally less than those of urban site. Mean fraction of 76.5% and 63.9% of the total PAH were associated with particles of 0.43-2.1 microm at rural and urban sites, respectively. Precipitation, temperature, wind speed and direction were the important meteorological factors influencing the concentration of PAHs in rural and urban sites. The distributions of PAHs concentration with respect to particle size were similar for rural and urban samples. The PAHs concentrations at the height of 40 m were higher than both of 20 and 60 m at urban site, but the mass median diameter (MMD) of total PAH increased with the increasing height. The mid-high molecular weight (278 >or= MW >or= 202) PAHs were mainly associated with fine particles (Dp <or= 2.1 microm), whereas low molecular weight (128 >or=MW >or=178) PAHs were distributed in both of fine and coarse particle. The fraction of PAHs associated with coarse particles (Dp>2.1 microm) decreased with increasing molecular weight. The relatively consistent distribution of PAHs seemed to indicate the similar combustion source of PAHs at both of rural and urban sites. The fine differences of concentration and distribution of PAHs at different levels at urban site suggested that the different source and transportation path of particulate PAHs.
Collapse
|
9
|
Polycyclic aromatic hydrocarbons in dustfall in Tianjin, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2005; 345:115-26. [PMID: 15919533 DOI: 10.1016/j.scitotenv.2004.11.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2004] [Accepted: 11/05/2004] [Indexed: 05/02/2023]
Abstract
Atmospheric dustfall samples from 23 locations in Tianjin, China, were collected and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs) classified by the Environmental Protection Agency as priority pollutants from March 2002 to March 2003. SigmaPAH16 (sum of 16 PAH compounds) concentrations in the dustfall collected during heating season ranged from 2.5 to 85.5 mug/g, while that during the non-heating season varied from 1.0 to 48.2 microg/g dry weight. The dominant components in the heating season included naphthalene, phenanthrene, fluoranthene, and chrysene, while naphthalene, fluorene, phenanthrene, and fluoranthene were dominant during the non-heating season. Compared with the non-heating season, the heating season was characterized by a higher fraction of high-molecular-weight PAHs with four to six rings with exception of the samples from the east industrial area. The east industrial area had more significant correlations between individual PAH compounds, and more discrete triangular components of three-, four-, five- and six-ring PAHs. No significant correlations were observed between the PAHs concentrations and total organic carbon (TOC) in the dustfall samples. The deposition fluxes of sigmaPAH15 (sum of 15 PAHs except naphthalene), sigmaPAH6 (sum of 6 carcinogenic PAHs recommended by IARC) and benzo[a]pyrene (BaP) from atmospheric deposition to the whole area were estimated as 1911, 196, and 53 microg/m2/year, respectively. The deposition rates for PAH compounds in the east industrial area were higher than those in the urban and rural areas. Furthermore, the deposition contribution of PAHs during domestic heating season in winter was not significant relative to the annual inputs.
Collapse
|
10
|
Contamination of rivers in Tianjin, China by polycyclic aromatic hydrocarbons. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2005; 134:97-111. [PMID: 15572228 DOI: 10.1016/j.envpol.2004.07.014] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2004] [Accepted: 07/02/2004] [Indexed: 05/24/2023]
Abstract
Tianjin urban/industrial complex is highly polluted by some persistent organic pollutants. In this study, the levels of 16 priority polycyclic aromatic hydrocarbons (PAHs) were tested in sediment, water, and suspended particulate matter (SPM) samples in 10 rivers in Tianjin. The total concentration of 16 PAHs varied from 0.787 to 1943 microg/g dry weight in sediment, from 45.81 to 1272 ng/L in water, and from 0.938 to 64.2 microg/g dry weight in SPM. The levels of PAHs in these media are high in comparison with values reported from other river and marine systems. Variability of total concentrations of PAHs in sediment, water, and SPM from nine different rivers is consistent with each other. No obvious trends of total PAHs concentration variations were found between upstream and downstream sediment, water, and SPM samples for most rivers, which indicate local inputs and disturbances along these rivers. The spatial distributions of three-phase PAHs are very similar to each other, and they are also similar to those found in topsoil. However, their chemical profiles are significantly different from that of topsoil. The change of profiles is consistent with the different aqueous transport capability of 16 PAHs. Low molecular weight PAHs predomination suggests a relatively recent local source and coal combustion source of PAHs in the study area.
Collapse
|
11
|
Coronary smooth muscle differentiation from proepicardial cells requires rhoA-mediated actin reorganization and p160 rho-kinase activity. Dev Biol 2001; 240:404-18. [PMID: 11784072 DOI: 10.1006/dbio.2001.0403] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We recently reported that the first detectable expression of SMC-specific proteins during coronary smooth muscle cell (CoSMC) differentiation from isolated proepicardial cells was restricted to cells undergoing epithelial-to-mesenchymal transformation (EMT). The objectives of this study were to examine more closely the relation between actin cytoskeletal rearrangements and serum response factor (SRF)-dependent transcription, and to specifically test whether rhoA-GTPase signaling is required for CoSMC differentiation. We report here that PDGF-BB stimulates EMT and promotes SRF-dependent expression of SMC marker genes calponin, SM22alpha, and SMgamma(actin) (SMgammaA) in proepicardial cells. C3 exoenzyme or rhoGDI, inhibitors of rhoA signaling, blocked PDGF-BB-induced EMT, prevented actin reorganization into stress fibers, and inhibited CoSMC differentiation. Incubation with the selective p160 rho-kinase (p160RhoK) inhibitor Y27632 (RKI) blocked EMT, prevented the appearance of calponin and SMgammaA-positive cells, and abolished expression and nuclear localization of SRF. To test the role of RhoK signaling for CoSMC differentiation in vivo, quail proepicardial organs (PEOs) were pretreated with RKI or vehicle and then grafted into age-matched host chick embryos to produce a chimeric epicardium. The ability of grafted cells to participate in coronary vessel formation was monitored by staining with antibodies for quail cell nuclear antigen and SMC marker proteins. Proepicardial cells pretreated with RKI failed to form CoSMCs in vivo. Time course studies traced this deficiency to a failure of epicardial-derived mesenchymal cells to migrate into or survive within the myocardium. In summary, these data point to important roles for rhoA-RhoK signaling in molecular pathways controlling cytoskeletal reorganization, SRF-dependent transcription, and cell survival that are required to produce CoSMCs from proepicardial cells.
Collapse
|
12
|
Psychophysical determination of load carrying capacity for a 1-h work period by Chinese males. ERGONOMICS 2001; 44:1008-1023. [PMID: 11693245 DOI: 10.1080/00140130110076358] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study used the psychophysical approach to examine the effects of container width, the presence or absence of container handles, and different load-carrying frequencies and distances on the maximum acceptable weight carried and the resulting response (heart rate and rating of perceived exertion) by well-conditioned males for a 1-h work period. After training, 12 male subjects performed a load-carrying task at knuckle height. Each subject performed 30 different carrying combinations. The conditions examined were container width, from 15.2 to 55.9 cm; carrying frequency, from 1 carry to 5 carries/min; and carrying distance from 1 to 6 m. The results were compared with prior studies and led to the following conclusions: (1) the use of container handles leads to the subjects carrying a significantly higher maximum acceptable weight than when containers do not have handles, which differs from the results of a previous study by Morrissey and Liou; (2) there were significant reductions in the maximum acceptable carrying weight with increases in container width, frequency and distance; (3) the presence or absence of container handles, different frequencies and load-carrying distances had significant effects on heart rate, although the effect of container width was not significant. In addition, the various frequencies and distances for load carrying had significant interaction effects on heart rate; (4) the effects of various frequencies and load-carrying distances on the rating of perceived exertion were statistically significant. The most stressed body parts were the wrists and arms.
Collapse
|
13
|
E-cadherin expression and PSA secretion in human prostate epithelial cells. UROLOGICAL RESEARCH 2001; 29:287-92. [PMID: 11585286 DOI: 10.1007/s002400100188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Prostate-specific antigen (PSA) is the most widely used marker for the diagnosis of prostate cancer and is an independent predictor of prostatic capsular invasion. A number of studies have identified E-cadherin, a cell adhesion protein, as a potential invasion suppressor which is decreased in prostate adenocarcinoma. Our goal in the present study was to evaluate E-cadherin expression in primary cultures and determine the relationship between E-cadherin expression and PSA secretion in both primary cultures and the prostate tumor cell line, LNCaP. Immunohistochemical studies and Western blot analysis confirmed greater expression of E-cadherin in normal epithelial cells than tumor-derived prostate cells. This is the first report that the incubation of normal prostate epithelial cells with E-cadherin antibody increases the amount of PSA detected in the media of normal cells as well as in LNCaP. Since E-cadherin may function as an invasion suppressor, an understanding of the decreased expression of this adhesion factor and the impact on PSA secretion may aid in understanding epithelial tumorigenesis.
Collapse
|
14
|
Promotion of forskolin-induced long-term potentiation of synaptic transmission by caffeine in area CA1 of the rat hippocampus. CHINESE J PHYSIOL 1999; 42:249-53. [PMID: 10707900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Caffeine which is present in soft drinks has been shown to increase alertness and allays drowsiness and fatigue. The aim of this study is to investigate whether caffeine could produce a long-term effect on the synaptic transmission using extracellular recording technique in the hippocampal slices. Bath application of caffeine (100 microM) reversibly increased the slope of field excitatory postsynaptic potential (fEPSP). Forskolin (25 microM) by its own did not affect the fEPSP significantly. However, in the presence of caffeine, forskolin induced a long-term potentiation (LTP) of fEPSP. Enprofylline which has been shown to exhibit some actions like caffeine but with a low adenosine antagonistic potency did not affect the normal synaptic transmission or the effect of forskolin at a lower concentration (10 microM). However, when the concentrations were increased to 20 and 50 microM, enprofylline significantly enhanced the fEPSP slope and promoted forskolin-induced LTP. The parallel increase of fEPSP and promotion of LTP observed with enprofylline suggests that adenosine A1 antagonism is the primary mechanism behind caffeine's effect. This hypothesis was further strengthened by the finding that promotion of forskolin-induced LTP was mimicked by the non-xanthine adenosine antagonist 9-chloro-2-(furyl)[1,2,4]triazolo [1,5-c]quinazolin-5-amine (CGS 15943). The promotion of forskolin-induced LTP provides a cellular basis behind caffeine's increase in capacity for sustained intellectual performance.
Collapse
|
15
|
Abstract
Mitogen-activated protein kinase (MAPK) cascade classically is thought to be involved in cellular transformation, including proliferation and differentiation. Recent behavioral studies suggest that MAPK may also have a role in learning and memory. Long-term potentiation (LTP), a candidate mechanism for learning and memory, has at least two distinct temporal phases: an early phase (E-LTP) which lasts for 1-2 h and a late phase (L-LTP) which can persist >/=3 h. Here, we report that PD 098059, a selective inhibitor of MAPK cascade, attenuates L-LTP induced by bath application of forskolin without affecting basal synaptic transmission. This effect was mimicked by direct injection of animals with MAPK antisense oligonucleotide into the hippocampal CA1 region. MAPK activity measured by using a synthetic peptide corresponding to the sequence surrounding the major site of phosphorylation of the myelin-basic protein by MAPK was enhanced by forskolin. The same antisense treatment also completely inhibited the increased MAPK activity. These results demonstrate an involvement of MAPK in the induction of L-LTP in the hippocampal CA1 neurons.
Collapse
|
16
|
Crystallization and preliminary crystallographic analysis of the Escherichia coli tyrosine aminotransferase. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1999; 55:1474-7. [PMID: 10417420 DOI: 10.1107/s0907444999006630] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Tyrosine aminotransferase catalyzes transamination for both dicarboxylic and aromatic amino-acid substrates. The substrate-free Escherichia coli tyrosine aminotransferase (eTAT) bound with the cofactor pyridoxal 5'-phosphate (PLP) was crystallized in the trigonal space group P3(2). A low-resolution crystal structure of eTAT was determined by molecular-replacement methods. The overall folding of eTAT resembles that of the aspartate aminotransferases, with the two identical subunits forming a dimer in which each monomer binds a PLP molecule via a covalent bond linked to the epsilon-NH(2) group of Lys258. Comparison of the structure of eTAT with those of the open, half-open or closed form of chicken or E. coli aspartate aminotransferases shows the eTAT structure to be in the open conformation.
Collapse
|
17
|
Psychophysically determined infrequent lifting capacity of Chinese participants. ERGONOMICS 1999; 42:952-963. [PMID: 10424184 DOI: 10.1080/001401399185234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The aim of this study was to investigate the psychophysical infrequent lifting capacity (maximum acceptable weight of lift, MAWL) for a Chinese population. A nested-factorial experimental design with a participant factor nested within gender was employed. Forty-one Chinese participants (29 males, 12 females) participated in the study. Two frequencies (one lift every 8 h and one lift every 5 min) and six lifting heights (floor to knuckle, floor to shoulder, floor to reach, knuckle to shoulder, knuckle to reach, shoulder to reach) were evaluated. The results are compared with prior studies and they lead to the following conclusions. (1) The MAWLs were significantly affected by both the lifting frequency and lifting height. For lifting frequency, the MAWLs decreased markedly by nearly 30% from one lift every 8 h to one lift every 5 min. For lifting height, the MAWLs of the F-K was the greatest of all six lifting heights, followed by F-S, K-S, F-R, K-R and S-R was the smallest. (2) The MAWLs for Chinese females are significantly lower, but proportionately similar, to the MAWLs for Chinese males. (3) The Chinese participants had smaller capacities compared with the Occidental participants, and the rate of decrease in MAWL for the Chinese participants was much sharper than that of Occidental participants. (4) The MAWL of Chinese females was about 54-58% of the Chinese males, it is somewhat lower than those of 60-70% of the Occidental participants.
Collapse
|
18
|
Effect of immune response on gene transfer to the lung via systemic administration of cationic lipidic vectors. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:L796-804. [PMID: 10330036 DOI: 10.1152/ajplung.1999.276.5.l796] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cationic lipid-mediated intravenous gene delivery shows promise in treating pulmonary diseases including lung tumor metastases, pulmonary hypertension, and acute respiratory distress syndrome. Nevertheless, clinical applications of cationic lipidic vectors via intravenous administration are limited by their transient gene expression. In addition, repeated dosing is not effective at frequent intervals. In an effort to elucidate the mechanism of gene inactivation, we report in this study that cationic lipid-protamine-DNA (LPD) complexes, but not each component alone, can induce a high level of cytokine production, including interferon-gamma and tumor necrosis factor-alpha. Furthermore, we demonstrate that LPD administration triggers apoptosis in the lung, a phenomenon that may be mediated in part by the two cytokines. Treatment of mice with antibodies against the two cytokines prolongs the duration of gene expression and also improves lung transfection on a second administration of LPD. Although the mechanism underlying LPD-induced cytokine production is unclear, methylation of the DNA significantly decreased the level of both interferon-gamma and tumor necrosis factor-alpha, suggesting that unmethylated CpG sequences in plasmid DNA play an important role. These data suggest that decreasing the CpG-mediated immune response while not affecting gene expression may be a useful therapeutic strategy to improve cationic lipid-mediated intravenous gene delivery to the lung.
Collapse
|
19
|
Dynamic changes in the characteristics of cationic lipidic vectors after exposure to mouse serum: implications for intravenous lipofection. Gene Ther 1999; 6:585-94. [PMID: 10476218 DOI: 10.1038/sj.gt.3300865] [Citation(s) in RCA: 283] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intravenous gene delivery via cationic lipidic vectors gives systemic gene expression particularly in the lung. In order to understand the mechanism of intravenous lipofection, a systematic study was performed to investigate the interactions of lipidic vectors with mouse serum emphasizing how serum affects the biophysical and biological properties of vectors of different lipid compositions. Results from this study showed that lipidic vectors underwent dynamic changes in their characteristics after exposure to serum. Addition of lipidic vectors into serum resulted in an immediate aggregation of vectors. Prolonged incubation of lipidic vectors with serum led to vector disintegration as shown in turbidity study, sucrose-gradient centrifugation analysis and fluorescence resonance energy transfer (FRET) study. Vector disintegration was associated with DNA release and degradation as shown in EtBr intercalation assay and DNA digestion study. Serum-induced disintegration of vectors is a general phenomenon for all cationic lipidic vectors tested in this study. Yet, vectors of different lipid compositions vary greatly in the rate of disintegration. There is an inverse correlation between the disintegration rate of lipidic vectors and their in vivo transfection efficiency. Vectors with a rapid rate of disintegration such as those containing dioleoyl-phosphatidylethanolamine (DOPE) poorly stayed in the lung and were barely active in transfecting cells. In contrast, cholesterol-containing vectors that had a rapid aggregation and a slow disintegration were highly efficient in transfecting cells in vivo. The results of this study explain why cationic lipidic vectors of different lipid compositions have a dramatic difference in their in vivo transfection efficiency. These results also suggest that the study of the interactions of lipidic vectors with serum may serve as a predictive model for the in vivo efficiency of a lipidic vector. Further study of the numerous interactions of lipidic vectors with serum might lead to the development of a vector which can deliver a gene to target cells in a tissue-specific manner.
Collapse
|
20
|
Improving the catalytic activity of phenylalanine aminotransferase of Escherichia coli by site-specific mutation. Ann N Y Acad Sci 1998; 864:561-4. [PMID: 9928139 DOI: 10.1111/j.1749-6632.1998.tb10381.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
21
|
Abstract
1. Topiramate is a structurally novel anticonvulsant which was recently approved for adjunctive therapy in partial and secondarily generalized seizures. The present study was aimed at elucidating the mechanisms underlying the anticonvulsant efficacy of topiramate using intra- and extracellular recording techniques in the in vitro hippocampal slices. 2. When stimuli were delivered every 20 s, topiramate had no measurable effect on both field excitatory postsynaptic potentials (fEPSPs) and population spikes (PSs). However, increasing the stimulation frequency from 0.05-0.2 Hz, topiramate significantly decreased the slope of fEPSP and the amplitude of PS in a concentration-dependent manner. The amplitude of presynaptic fiber volley was also reduced. 3. Topiramate did not affect the magnitude of paired-pulse inhibition and monosynaptically evoked inhibitory postsynaptic potentials (IPSPs). 4. Sustained repetitive firing was elicited by injection of long duration (500 ms) depolarizing current pulses (500-800 pA). Superfusion with topiramate significantly reduced the number of action potentials evoked by a given current pulse. 5. After blockade of GABA receptors by bicuculline, burst firing which consisted of a train of several spikes riding on a large depolarizing wave termed paroxysmal depolarizing shift (PDS) was recorded. Application of topiramate reduced the duration of PDS and later spikes with less effect on the initial action potential. 6. These results suggest that frequency-dependent inhibition of neuronal activity due to blockade of Na+ channels may account largely for the anticonvulsant efficacy of topiramate.
Collapse
|
22
|
Cancellation of low-frequency stimulation-induced long-term depression by docosahexaenoic acid in the rat hippocampus. Neurosci Lett 1998; 247:198-200. [PMID: 9655627 DOI: 10.1016/s0304-3940(98)00272-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The effects of docosahexaenoic acid (DHA) on low-frequency stimulation (LFS)-induced long-term depression (LTD) were investigated in the CA 1 subfield of rat hippocampal slices. LTD was routinely produced by LFS of 900 pulses at 1 Hz. The field excitatory postsynaptic potential (fEPSP) 40 min after LFS was 59 +/- 4% (n = 18) of baseline response. However, in experiments from 18 neurons pretreated with DHA (50 microM), fEPSP returned to baseline levels within 20 min after LFS in eight cells and was slightly potentiated in three cells. Only in seven cells was LTD induced. The effect of DHA on LTD was concentration dependent. The slopes of fEPSP 40 min after LFS were 67 +/- 4% (n = 6), 72 +/- 7% (n = 7) and 80 +/- 5% (n = 18) of baseline response, with pretreatment of 1, 10 and 50 microM DHA, respectively. The blockade of LTD induction suggests that DHA may play a role in learning and memory.
Collapse
|
23
|
Maximum acceptable weight of lift by Chinese experienced male manual handlers. APPLIED ERGONOMICS 1997; 28:237-244. [PMID: 9414362 DOI: 10.1016/s0003-6870(96)00080-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This study uses a psychophysical methodology to determine the maximum acceptable weight of lift (MAWL) for 13 Chinese experienced male subjects, and examines the effects of variations in box size (including 300, 450 and 600 mm, sagittal distance from body) and lifting frequency (including one-time-maximum, 1, 4 and 6 lifts/min) on the MAWL, and the resulting responses [heart rate and rating of perceived exertion (RPE)]. The results are compared with prior studies and lead to the following conclusions: (1) Increases in both the box size and lifting frequency induced a significant decrease in MAWL, and a significant increase in RPE and heart rate. However, overall RPE ratings were not increased significantly with box size. (2) For Chinese inexperienced male subjects, the overall MAWL and heart rate were approximately 85% and 91% of their experienced male counterparts, respectively. The decrement in MAWL with Occidental subjects was about the same for both experienced and inexperienced groups; (3) The average MAWL values of Chinese subjects were smaller than those of Occidental subjects, and the average rate of decrease in MAWL with increasing of lifting frequency for the Chinese subjects was much sharper than in Occidental subjects; (4) There was no significant difference in overall heart rate and RPE ratings between the Chinese subjects and Occidental subjects. However, the body part RPE ratings were different from the previous studies. The present study found the most stressed body parts were the back and wrist, which may have been caused by the height of the table (760 mm) and the smaller body size of the Chinese subjects compared with the Occidental subjects.
Collapse
|
24
|
Identification and purification of a spinach chloroplast DNA-binding protein that interacts specifically with the plastid psaA-psaB-rps14 promoter region. PLANTA 1997; 203:373-380. [PMID: 9431684 DOI: 10.1007/s004250050203] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We have previously shown the presence in chloroplasts of sequence-specific DNA-binding proteins that interact specifically with two regions located downstream and upstream from the 5'-transcription start site of the plastid psaA-psaB-rps14 operon. As part of an effort to elucidate the regulatory mechanism of plastid transcription during plant development, we report here the purification and characterization of the chloroplast DNA-binding protein from spinach (Spinacia oleracea L. var. spinosa Ashers et Graeden) leaves that specifically recognizes sequences between positions +64 to +83 relative to the transcription start site. This DNA-binding protein has been highly purified from chloroplasts by using a combination of high-salt extraction, ammonium sulfate precipitation, heparin-agarose chromatography, and sequence-specific DNA-affinity chromatography. The protein exhibited an apparent molecular weight of 59-60 kDa on the basis of gel filtration. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Southwestern blot analysis further indicated that this DNA-binding protein is dimeric and composed of two approximately 31-kDa subunits. We discuss the properties of this protein in relation to the known chloroplast DNA-binding factors for plastid gene expression.
Collapse
|
25
|
Hepatic expression of hepatitis C virus RNA in chronic hepatitis C: a study by in situ reverse-transcription polymerase chain reaction. Hepatology 1996; 23:1318-23. [PMID: 8675145 DOI: 10.1002/hep.510230604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Hepatitis C virus (HCV) replicates at a low rate and this makes its detection and intrahepatic localization difficult. To evaluate the clinical implications and effect of interferon alfa (IFN-alpha) therapy on hepatic expression of HCV RNA, HCV RNA was detected by in situ reverse-transcription polymerase chain reaction (IS-RT-PCR) in formalin-fixed paraffin-embedded liver sections from 26 patients with chronic hepatitis C. Results were compared with RT-PCR of HCV RNA extracted from liver sections/tissue. Twenty-four paired post-IFN-alpha treatment biopsy specimens were also assessed. Using RT-PCR of the extracted RNA as a positive standard and non-HCV liver sections as the negative standard, the sensitivity and specificity of IS-RT-PCR were 69% and 100%, respectively. HCV RNA was detected in the cytoplasm of hepatocytes (median, 5% hepatocytes positive; range, 0 to 35%) and very occasionally in infiltrating mononuclear cells. There was no correlation between hepatic expression of HCV RNA and the clinical, biochemical parameters, total and activity scores of histology activity index. Presence of HCV RNA in liver as detected by IS-RT-PCR was associated with higher serum HCV RNA levels (4.9 x 10(6) vs. 0.4 x 10(6) genome Eq/mL, P < .01). There was no difference in the pretreatment proportion of HCV RNA-positive hepatocytes among patients with different biochemical responses to IFN-alpha therapy. In the posttreatment samples, HCV RNA was undetectable by IS-RT-PCR in 16 of 24 patients (P < .01), including all 4 patients who had complete and sustained response (SR). We conclude that HCV RNA was detected by IS-RT-PCR in 0 to 35% of hepatocytes in patients with chronic HCV infection, detection of HCV RNA in liver by IS-RT-PCR was associated with higher viremia levels and IFN-alpha therapy reduced hepatocytic expression of HCV RNA.
Collapse
|
26
|
In vivo antitumor activity of cis-bis-neodecanoato-trans-R,R-1, 2-diaminocyclohexane platinum(II) formulated in long-circulating liposomes. Cancer Chemother Pharmacol 1996; 37:435-44. [PMID: 8599866 DOI: 10.1007/s002800050409] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A lipophilic cisplatin derivative, cis-bis-neodecanoato-trans- R,R-1,2-diaminocyclohexane platinum (II) (NDDP), was formulated in liposomes composed of phosphatidylcholine (PC) and cholesterol (Chol) additionally containing monosialoganglioside (Gm1) or polyethyleneglycol conjugated to phosphatidylethanolamine (PEG-PE). These NDDP-containing long-circulating liposomes were examined for in vivo antitumor activity using the mouse RIF-1 solid tumor as a target residing outside the reticuloendothelial system (RES). Biodistribution studies, using C3H/HeJ mice and 111In-labelled DTPA-SA as a lipid marker, showed that the activity of GM1 and PEG-PE in prolonging the circulation times of liposomes was preserved in the presence of 3.0 mol% of NDDP in the liposome membranes. The high levels of liposomes remaining in the blood for PC/Chol/GM1 and PC/Chol/PEG3000-PE liposomes were associated with high levels of platinum in the blood as determined by atomic absorption spectrophotometry. These NDDP-containing long-circulating liposomes showed approximately a three-fold increase in tumor accumulation as compared to the conventional PC/Chol liposomes. In vitro cytotoxicity studies using RIF-1 tumor cells showed that the presence of PEG-PE, but not Gm1, significantly enhanced the cytotoxicity of liposomal NDDP. RIF-1 tumor-bearing C3H/HeJ mice were treated twice with 25 mg/kp NDDP in various liposomal formulations on days 12 and 16 after tumor cell inoculation. A significant reduction in the tumor growth rate was observed when NDDP was formulated in PC/Chol/PEG3000-PE liposomes which support both efficient tumor accumulation and enhanced cytotoxicity of liposomal NDDP. On the other hand, NDDP formulated in PC/Chol/GM1 liposomes, which display only a high tumor accumulation, had no effect on the tumor growth rate. Furthermore, NDDP formulated in dimyristoylphosphatidylglycerol (DMPG)-containing liposomes, exhibiting in vitro cytotoxicity comparable to NDDP formulated in PC/Chol/PEG3000-PE liposomes, but showing poor tumor accumulation, was also not effective. These results indicate a potential effectiveness of NDDP formulated in PEG-PE-containing liposomes for therapy of tumors in non-RES organs.
Collapse
|
27
|
Abstract
A very large radial graded-index (GRIN) polymer was successfully prepared for the first time, to the best of our knowledge, by two methods: the curved mold method and the diffusion copolymerization method. Both methods gave a radial GRIN polymer with a diameter of 70 mm and a ∆n value greater than 0.02. Ray tracing through these radial GRIN polymers was used to predict that such a GRIN polymer could be a promising candidate for thinner ophthalmic lenses with no spherical aberration or multifocusing characteristics.
Collapse
|
28
|
Effects of the handle diameter and tip angle of chopsticks on the food-serving performance of male subjects. APPLIED ERGONOMICS 1995; 26:379-385. [PMID: 15677038 DOI: 10.1016/0003-6870(95)00050-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effects of chopsticks handle diameter and tip angle on the food-serving performance of pinching food, pulling food, shearing food and thrusting food, were investigated in this study. A total of 24 male subjects was tested using 12 pairs of experimental chopsticks, consisting of three types of different handle diameters and four types of different tip angles. These results indicated that chopstick handle diameter and tip angle have a significant influence on eating efficiency, and that these two variables have a significant interaction. In addition, chopstick tip diameter also had significant effects on performance at the four tasks and subjective ratings. Generally, according to the results, when the chopsticks design is presented in terms of handle diameter, tip angle and tip diameter, a pair of chopsticks with 6 mm handle diameter x 2 degrees tip angle x 4 mm tip diameter would be optimum.
Collapse
|
29
|
Abstract
BACKGROUND AND PURPOSE Incidence of stroke varies markedly in different world populations. In seven Chinese cities, the effect of a program of risk factor modification on the incidence and mortality of stroke was studied and compared with a control population. This article describes the incidence of stroke in the control populations for the years 1986 through 1990. METHODS Incidence (first-ever strokes only) for 1986 was obtained by door-to-door interview with heads of households with subsequent verification on examination by a neurologist and review of medical and/or hospital records. In subsequent years, cases were ascertained with a three-tier monitoring system: by community health workers, local medical centers, and the Beijing Neurosurgical Institute. RESULTS Average annual age-adjusted incidence per 100,000 was 215.6 (261.5 for males, 174.5 for females; P < .001). There was a significant drop in the total number of cases from 137 in 1986 to 106 in 1990, but the age-adjusted rate showed a significant drop for males only (322.3 to 182.5, P < .001). Marked differences in average annual age-adjusted rates existed among the seven cities, from 486.4 for Harbin to 80.9 for Shanghai. This difference in rate among cities was found for both sexes but was more pronounced in males. CONCLUSIONS The stroke incidence rates in China, like those in Japan, are among the higher ones in the world. In recent years, there has been an apparent decline in stroke incidence. Marked differences in rates were found between males and females with decline in incidence occurring almost exclusively in males. There were also marked differences in stroke incidence among the cities studied. These differences may result in part from differences in diet, alcohol and cigarette consumption, or prevalence of hypertension.
Collapse
|
30
|
Abstract
A gradient-index (GRIN) contact lens (CL) is proposed to decrease spherical aberration and to increase the diopter. A plastic radial GRIN rod was successfully obtained by using the vapor-phase diffusion copolymerization technique. The resulting index distribution of the GRIN rod was almost parabolic against the distance from the center axis, and the Δn value was -0.030. The GRIN CL was prepared by grinding and polishing the rod. It is theoretically and experimentally concluded that using the radial GRIN material can significantly improve the optical properties of CL's.
Collapse
|
31
|
Abstract
The psychophysical lifting capacity (MAWL) of twelve subjects was determined in this study. The subjects were all young Chinese males who performed lifting tasks in three lifting ranges (floor to knuckle, floor to shoulder, and knuckle to shoulder) and four lifting frequencies (one-time maximum, 1 lift/min, 4 lifts/min, and 6 lifts/min). The oxygen uptake (1/min) and heart rate (beats/min) were recorded while subjects were lifting. Upon completion of each lifting task, the subjects were required to rate their perceived exertion levels. The statistical analyses results indicated the following. Chinese subjects have smaller body size and MAWLs compared with past studies using the US population. The MAWLs decreased with an increase in lifting frequencies. The decrements of MAWL due to lifting frequencies were in agreement with the results of past studies. However, there were larger decreases due to lifting ranges. The MAWLs of the floor to knuckle height lift were the largest, followed by the MAWLs of the floor to shoulder height lift, and the MAWLs of the knuckle to shoulder height lift. The measured physiological responses were considered similar to those obtained in past studies. Subjects' perceived stress levels increased with the lifting frequency and the upper extremities received the most stress for the total range of lifting tasks. The comparisons of the Chinese MAWLs with the NIOSH lifting guidelines for limits (AL and MPL) indicated that the vertical discounting factor in the guidelines should be modified before the NIOSH limits can be applied to non-Western populations.
Collapse
|
32
|
Abstract
Colon carcinoma is a multistage disease. Most malignancies arise from pre-existing benign tumors. Multiple chromosomal defects affecting oncogene and tumor suppressor gene function are associated with disease progression. These aberrations result in an imbalance between the normal positive and negative growth effectors, which contribute further to disease progression. We have studied how changes in the expression of TGF alpha and TGF beta affect colon carcinoma cell behavior. Overexpression of the stimulatory factor TGF alpha in a relatively benign cell line with weak TGF alpha autocrine activity converted the cell type to an aggressive, progressed phenotype in vivo and in vitro. In contrast, disruption of TGF alpha expression by constitutive expression of TGF alpha antisense RNA in a progressed cell line with a strong, internalized autocrine loop resulted in the development of clones with decreased tumorigenicity in vitro and in vivo. Suppression of the inhibitory effects of TGF beta by constitutive expression of TGF beta antisense RNA increased the tumorigenicity of the cell lines in vitro and in vivo. None of these alterations in TGF alpha or TGF beta expression affected the doubling time of the cells. The changes in tumorigenicity were due to effects on the lag phase of growth. We conclude that TGF beta functions to maintain the cells in a quiescent state while TGF alpha drives reentry into the cell cycle. We have identified a unique cis-element that mediates TGF alpha autoregulation. The transcription factor binding this element is also involved in the cell-cycle regulation of TGF alpha expression. We hypothesize that this factor may be a convergent point TGF alpha and TGF beta interact in controlling movement into and out of quiescence.
Collapse
|
33
|
Psychophysical modelling of lifting capacity of Chinese males using strength variables. APPLIED ERGONOMICS 1993; 24:251-257. [PMID: 15676920 DOI: 10.1016/0003-6870(93)90459-m] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This study used the psychophysical approach to determine the maximum acceptable weight of lift (MAWL) for 12 young Chinese male subjects, and used strength variables as predictors to develop prediction models. Each subject performed 12 different lifting tasks involving three lifting heights and four lifting frequencies. The results showed that both the dynamic and static models developed in this study could predict the MAWL with a reasonable degree of accuracy. However, a comparison of the models revealed that the use of the dynamic model resulted in less PRESS (PRediction Error Sum of Squares) statistics and higher [Formula: see text] values than the static model. Isoinertial 1.83 m maximum strength (T1) and the isoinertial elbow-height strength, tested on an incremental weightlifting machine, were found to be the best screening test. This was different from a previous study that recommended T1 as the most promising single screening test for Occidentals.
Collapse
|
34
|
Sweat gland carcinoma: an easily confused skin malignancy. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1993; 51:355-60. [PMID: 8334563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Sweat gland carcinoma is a rare malignancy of the skin appendage. Surgeons and pathologists have limited experience with such tumor. Various classifications and diagnostic identifications lead to easy confusion with other metastatic lesions. Eight cases of sweat gland carcinoma were collected from 1020 cases of primary skin malignancies seen at the Veterans General Hospital-Taipei over the past 20 years. After a careful review of the clinical history and histopathology files, as well as immunohistochemical stains of CEA and S-100 protein, only three cases were proved to be sweat gland carcinomas, accounting for less than 0.3% of the primary tumors of skin. All three cases were eccrine histology in type. Two cases were CEA positive, and one case was positive with S-100 protein stain. Five cases which were excluded were negative to CEA and S-100 protein analysis. Thus it is suggested that sweat gland carcinoma should receive more accurate differential diagnosis from other skin malignancies, particularly metastatic tumors. Immunohistochemical analysis could help differential diagnosis. Treatment modalities of sweat gland carcinoma base mainly upon adequate wide surgical excision.
Collapse
|
35
|
Repression of autocrine transforming growth factor beta 1 and beta 2 in quiescent CBS colon carcinoma cells leads to progression of tumorigenic properties. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1993; 4:115-23. [PMID: 8494782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Previous work has shown that repression of negative autocrine transforming growth factor (TGF) beta 1 did not alter the growth rate of a human colon carcinoma cell line, but the time required for the cells to enter exponential growth from lag phase was reduced (S. P. Wu, D. Theodorescu, R. Kerbel, J. K. V. Willson, K. M. Mulder, L. E. Humphrey, and M. G. Brattain, J. Cell Biol., 116: 187-196, 1992). These results have led to the hypothesis that the tumor suppressive activity of autocrine TGF-beta 1 was directed at quiescent nondividing cells rather than actively dividing cells. In order to test this hypothesis, a weakly tumorigenic, well-differentiated human colon carcinoma cell line designated CBS, which expressed autocrine TGF-beta 1 and -beta 2 activity in quiescent cells, but not in exponential growth phase cells, was identified. This cell line was stably transfected with a full-length TGF-beta 1 antisense complementary DNA. Constitutive expression of TGF-beta 1 antisense mRNA in CBS cells resulted in repression of autocrine TGF-beta 1 and -beta 2 protein activity in quiescent cells of approximately 10-fold. TGF-beta 2 repression could have been due to interaction with TGF-beta 1 antisense mRNA, since these two isoforms have a high degree of homology, or it could have been indirectly due to TGF-beta 1 repression, since this isoform has been shown to affect transcriptional and posttranscriptional control of TGF-beta 2.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
36
|
[Intervention measures for diabetes mellitus in community population]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1992; 26:264-7. [PMID: 1298600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A prospective study was made of two randomly selected community population, one given diabetes mellitus intervention measures, the other as control. The results showed that the intervention group had significantly lower incidence of diabetes mellitus than the control group. It is suggested that a diabetes mellitus control program be tried with the municipal hospital as the centre in collaboration with primary health care units at the periphery.
Collapse
|
37
|
TGF-beta 1 is an autocrine-negative growth regulator of human colon carcinoma FET cells in vivo as revealed by transfection of an antisense expression vector. J Cell Biol 1992; 116:187-96. [PMID: 1730743 PMCID: PMC2289262 DOI: 10.1083/jcb.116.1.187] [Citation(s) in RCA: 151] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Transforming growth factor-beta 1 (TGF-beta 1) has previously been implicated as a potential negative autocrine or paracrine growth regulator of certain cell types (Arteaga, C. L., R. J. Coffey, Jr., T. C. Dugger, C. M. McCutchen, H. L. Moses, and R. M. Lyons. 1990. Cell Growth & Differ. 1:367-374; Hafez, M. M., D. Infante, S. Winawer, and E. Friedman. 1990. Cell Growth & Differ. 1:617-626; Glick, A. B., K. C. Flanders, D. Danielpour, S. H. Yuspa, and M. B. Sporn. 1989. Cell Regulation. 1:87-97). This is based mainly on experiments assessing the effects of exogenous TGF-beta 1 or neutralizing antibodies to TGF-beta 1 on normal or tumor cell proliferation in vitro. However, direct evidence demonstrating such a negative regulation of tumor cell growth in vivo is still lacking. To overcome this problem we have constructed and used an antisense expression vector for TGF-beta 1 as a means of regulating endogenous TGF-beta 1 expression in tumor cells. Antisense-transfected FET human colon carcinoma cells showed a fivefold reduction in TGF-beta 1 mRNA and 15-fold reduction in TGF-beta 1 secretion. Antisense mRNA was detected in transfected cells by an RNase protection assay. Compared to control cells, cultured antisense-transfected cells showed a reduction in lag phase time rather than a change in doubling time. Cloning efficiencies of transfected cells were four times greater than control cells in anchorage-independent assays. Control cells did not form tumors at 5 x 10(5) in athymic nude mice. Antisense-transfected cells formed tumors in 40% of animals injected. At higher inocula (1 x 10(6) cells) antisense-transfected cells formed tumors in 100% of animals injected, but control cells still failed to form tumors. These results show that TGF-beta 1 acts as a negative growth regulator of human colon carcinoma cells in vivo as well as in vitro. Acquisition of partial or full resistance to such inhibitory effects may therefore contribute to tumor development and progression.
Collapse
|
38
|
Abstract
Chopsticks are one of the most simple and popular hand tools ever invented by humans, but have not previously been investigated by ergonomists. Two laboratory studies were conducted in this research, using a randomised complete block design, to evaluate the effects of the length of the chopsticks on the food-serving performance of adults and children. Thirty-one male junior college students and 21 primary school pupils served as subjects for the experiment. The results showed that the food-pinching performance was significantly affected by the length of the chopsticks, and that chopsticks of about 240 and 180 mm long were optimal for adults and pupils, respectively. Based on these findings, the researchers suggested that families with children should provide both 240 and 180 mm long chopsticks. In addition, restaurants could provide 210 mm long chopsticks, considering the trade-offs between ergonomics and cost.
Collapse
|
39
|
Emergence and possible transmission of amantadine-resistant viruses during nursing home outbreaks of influenza A (H3N2). Am J Epidemiol 1991; 134:988-97. [PMID: 1951297 DOI: 10.1093/oxfordjournals.aje.a116184] [Citation(s) in RCA: 108] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Outbreaks of influenza A (H3N2, A/Shanghai/11/87-like) occurred in two partially (60% and 79%) vaccinated nursing home populations in January 1988. A retrospective cohort study using chart review was designed to assess the effectiveness of influenza vaccination and amantadine prophylaxis (100 mg per day) in controlling the outbreaks and to determine the amantadine susceptibility of influenza viruses isolated from case-patients. The point estimate of vaccine efficacy in preventing influenza-like illness was -33% (95% confidence interval -115% to 18%). However, 9% of vaccinated case-patients died within 14 days after onset of influenza-like illness compared with 26% of unvaccinated case-patients (relative risk = 0.4, 95% confidence interval 0.1-1.0). There was no significant difference in illness severity among case-patients who became ill before amantadine prophylaxis was started (n = 84) compared with those who became ill while taking amantadine (n = 34). Four virus isolates obtained before amantadine prophylaxis was started demonstrated 52-68% inhibition by 1 microgram/ml of amantadine; by comparison, six isolates (resistant viruses) obtained from residents who became ill while taking amantadine demonstrated 1-18% inhibition. The resistant viruses had four different RNA sequences in the gene coding for the M2 protein transmembrane region. Three resistant viruses with identical RNA sequences were isolated from residents living in contiguous rooms who had onset of signs and symptoms during a 6-day interval. Further studies are needed to determine how frequently and under what circumstances resistant viruses occur when antiviral agents are used to control institutional influenza A outbreaks. Strategies for antiviral agent administration that limit the emergence and transmission of resistant virus strains may be needed.
Collapse
|
40
|
[Treatment of hypertension syndrome of pregnancy with ligustrazine]. ZHONG XI YI JIE HE ZA ZHI = CHINESE JOURNAL OF MODERN DEVELOPMENTS IN TRADITIONAL MEDICINE 1991; 11:533-4, 516. [PMID: 1773467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
75 patients with hypertension syndrome of pregnancy (HSP) were randomly designed to 2 groups: the control group treated with magnesium sulfate (20-25g/d) and the Ligustrazine (120-160mg/d) group. The results of Ligustrazine group compared with the control group were as follows: (1) Mean arterial pressure was significantly decreased (P less than 0.01). (2) Edema and proteinuria was lowered (P less than 0.05). (3) The condition of rheology was improved, especially, hematocrit was significantly decreased (P less than 0.001). (4) The positive rate of NST and Apgar's score were not different between the 2 groups. Clinical monitoring showed Ligustrazine without side effects in the group. Mechanisms of Ligustrazine in HSP were (1) dilating blood vessel; (2) improving kidney function; (3) improving microcirculatory and rheology.
Collapse
|
41
|
[Aggressive fibrous histiocytoma of bone--report of two cases]. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1991; 48:158-62. [PMID: 1654189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Three osseous tumors multicentrically arising in the radius, ulna, and metacarpal bones of a 10-year-old girl and another in the femur of a 75-year-old man are reported. These lesions were designated as aggressive fibrous histiocytoma because of the benign cytological appearance with aggressive roentgenographic findings. These tumors were composed mainly of spindle cells tightly packed in a storiform pattern. Clear histiocytes and multinuclear giant tumor cells were occasionally seen. Variable amounts of collagen fiber were found. Both patients have been followed for 32 and 21 months respectively without evidence of local recurrence or distant metastasis.
Collapse
|
42
|
[Transforming growth factor in F9 embryonal carcinoma cells and its immunocytochemical localization]. SHI YAN SHENG WU XUE BAO 1986; 19:227-39. [PMID: 3554860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|