2151
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[Dynamic assay of oleanolic acid in Aralia taibaiensis Z. Z. Wang et H. C. Zheng]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1996; 21:200-2, 254. [PMID: 9208546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The dynamic assay on oleanolic acid (OA) in Aralia taibaiensis shows that the plant has a higher OA level. The level in root cortex is 4.74%-10.81% and peak stages are mid-May to late June and late August to mid-September the level in stem barks is 3.59%-12.06% and peak period is between mid-May and late July, the level in leaves increases throughout the life time ranging from 2.41% to 6.66% and peak level is 6.66% around mid-September.
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2152
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Changes in local immune functions in Mooren's ulcer. YAN KE XUE BAO = EYE SCIENCE 1996; 12:33-5. [PMID: 9275734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE To the investigate changes in local immune functions of the cornea and the adjacent conjunctiva, and their roles in the mechanism of the disease. METHOD The cornea and adjacent bulbar conjunctiva taken from 14 patients with Mooren's ulcer were stained immunohistochemically for CD3, CD4, CD8, HLA-DR, CD1 and CD25. RESULT An aberrant expression of HLA-DR antigen by a large number of kerato-conjunctival epithelial cells and keratocytes in the corneal stroma was found. The CD4+/CD8+ ratio is significantly higher than normal control. CONCLUSION The aberrant expression of MHC-II antigen in the resident cells at the peripheral cornea and the adjacent conjunctiva, along with a raised local TH/Ts ratio leading to an excessive autoimmune reactivity is possibly the direct cause of Mooren's ulcer.
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2153
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Nonconserved nucleotides at the 3' and 5' ends of an influenza A virus RNA play an important role in viral RNA replication. Virology 1996; 217:242-51. [PMID: 8599209 DOI: 10.1006/viro.1996.0111] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The genome of influenza A viruses is composed of eight negative-strand RNA segments which contain short noncoding regions at their 3' and 5' ends. The signals required for replication, transcription, and packaging of the viral RNAs are thought to be located in these regions. The highly conserved noncoding nucleotides, which form "panhandle" or "fork" structures by partial complementarity, are important for the transcriptional activity of the viral RNA polymerase. In contrast, the nonconserved noncoding nucleotides located close to the open reading frame of the viral RNAs had not been implicated in RNA transcription. Using a reverse-genetics system, we have now rescued influenza A/WSN/33 viruses whose NA-specific RNA segments have deletions in these nonconserved noncoding regions. Deletion either of the nucleotide residues between the poly(U) stretch and the stop codon at the 5' end or of the nucleotides between position 15 and the start codon at the 3' end did not affect the amount of NA-RNA species found in virions or infected cells. However, a combination of deletions at both the 3' and the 5' ends decreased by 60 times the levels of NA-specific viral RNA found in infected cells at late periods of infection and in virions. This double deletion was also responsible for a fourfold reduction of the steady-state levels of the NA-specific mRNA in infected cells. Viruses whose NA-specific open reading frames were flanked by the noncoding regions of the PB1- or the NS-RNA segments of infuenza A/WSN/33 virus also showed a reduction in the NA-specific viral RNA in virions and in infected cells. The present results demonstrate that the nonconserved nucleotides at the 3' and 5' ends of the NA-RNA segment of influenza A virus play an important role in the replication of this segment.
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2154
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Effect of quantum lattice fluctuations on the dimerized ground state of the Takayama-Lin-Liu-Maki model. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:2463-2473. [PMID: 9983749 DOI: 10.1103/physrevb.53.2463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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2155
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Tumor cell resistance to apoptosis due to a defect in the activation of sphingomyelinase and the 24 kDa apoptotic protease (AP24). FASEB J 1996; 10:325-32. [PMID: 8641566 DOI: 10.1096/fasebj.10.2.8641566] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Signal transduction pathways involved in apoptotic cell death are poorly understood, although recent studies have implicated sphingomyelin hydrolysis and generation of the second messenger, ceramide. Previous work in this laboratory demonstrated that a serine protease termed AP24 was activated by TNF or UV light and induced DNA fragmentation in isolated nuclei. This study extended these findings to examine the role of these enzymes in apoptosis of the U937 cell line and the mechanism of resistance of its variant, U9-TR. Although this subclone was selected by growth in TNF, it was unexpectedly found to resist apoptosis induced by UV light, but was still sensitive to anti-Fas-induced DNA fragmentation. Here we show that in contrast to normal U937 cells, UV light and TNF both failed to activate neutral or acidic sphingomyelinase or AP24 in the U9-TR variant. However, anti-Fas activated both neutral and acidic sphingomyelinase in the variant comparable to that seen in parental U937. The U9-TR variant could be sensitized to TNF or UV light activation of both sphingomyelinase and DNA fragmentation by the protein phosphatase inhibitors okadaic acid and calyculin A. Furthermore, exogenous bacterial-derived sphingomyelinase caused U9-TR activation of AP24 and DNA fragmentation comparable to that in the parental U937. Exposure of permeabilized U937 cells to ceramide caused internucleosomal DNA cleavage that was blocked by an inhibitor of AP24. Taken altogether, these findings demonstrate that TNF or UV light activate sphingomyelinase that leads to the generation of ceramide resulting in activation of AP24 and DNA fragmentation in sensitive cells. A selective defect in signals leading to sphingomyelinase activation can confer resistance to apoptosis even though the variant is still sensitive to downstream apoptotic signals such as nuclear DNA fragmentation by activated exogenous AP24.
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2156
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Metallothionein-I and -II knock-out mice are sensitive to cadmium-induced liver mRNA expression of c-jun and p53. Toxicol Appl Pharmacol 1996; 136:229-35. [PMID: 8619230 DOI: 10.1006/taap.1996.0029] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Zinc pretreatment has been shown in vitro (rat myoblasts) to induce metallothionein (MT) and inhibit cadmium (Cd)-induced protooncogenes c-myc and c-jun mRNA levels. therefore, the purpose of this study was to determine whether the mRNA expression of the protooncogene c-jun as well as the tumor suppressor gene p53 is increased by Cd in the intact animal and, more specifically, in the target organ for Cd toxicity, the liver. Additionally, modulation of the expression of these genes was investigated in the absence of MT. The effect of CdCl2 on the mRNA levels of c-jun and p53 was studied in livers of C57BL/6J (control) and MT-null mice by Northern- and slot-blot analyses. The mRNA for c-jun and p53 were increased by Cd in a dose-dependent fashion. In the control mice, Cd induced c-jun mRNA (5-fold) at 3 and 12 hr and p53 mRNA (1.8- to 2-fold) at 6 and 12 hr. Compared to controls, the MT-null mice were more sensitive to the Cd-induced gene expression. The magnitude of the inductions was more pronounced and the elevated mRNA levels of c-jun and p53 were seen at lower doses of Cd (10mumol/kg in MT-null mice vs 40 mmol/kg in control mice). In conclusion, these data demonstrate that Cd induces mRNA expression of the protooncogene c-jun and tumor suppressor gene p53 in liver, and that MT modulates this effect.
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2157
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[Studies on the immunopathogenesis of experimental tubulointerstitial nephritis in Wistar rats]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1996; 25:36-8. [PMID: 8762440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Tubulointerstitial nephritis (TIN) model was successfully induced in female Wistar rats by immunization with rabbit tubular basement membrane (TBM) etc. By using immunohistochemistry and computer assisted image processing, characterization of mononuclear cells in the TIN models were determined, and the relationship between Ia antigen expression of renal tissue and TIN studied. The results showed: TIN was characterized by deposition of IgG in a linear pattern along TBM and mononuclear cells infiltrates, which suggests the production of anti-TBM antibodies. Among the mononuclear cells, most are T cells. Granuloma formation was observed in parts of TIN. B cells gradually decreased while monocytes gradually increased. The renal tissue lesions show tubular atrophy and peritubular fibrosis. This model strongly suggests that cellular immune responses play an important role in the development of TIN. Ia antigen expression is higher in cells of the tubular epithelium and Bowman's capsule of lesion site than in control group (P < 0.01). This is strong evidence that the abnormal expression of Ia antigen may be affected by the production and development of TIN.
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2158
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Strain-specific reverse transcriptase PCR assay: means to distinguish candidate vaccine from wild-type strains of respiratory syncytial virus. J Clin Microbiol 1996; 34:334-7. [PMID: 8789010 PMCID: PMC228792 DOI: 10.1128/jcm.34.2.334-337.1996] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Candidate live-virus vaccines for respiratory syncytial virus are being developed and are beginning to be evaluated in clinical trials. To distinguish candidate vaccine strains from wild-type strains isolated during these trials, we developed PCR assays specific to two sets of candidate vaccine strains. The two sets were a group A strain (3A), its three attenuated, temperature-sensitive variant strains, a group B strain (2B), and its four attenuated, temperature-sensitive variant strains. The PCR assays were evaluated by testing 18 group A wild-type strains, the 3A strains, 9 group B wild-type strains, and the 2B strains. PCR specific to group A wild-type strains amplified only group A wild-type strains, and 3A-specific PCR amplified only 3A strains. PCR specific to group B wild-type strains amplified all group A and group B strains but gave a 688-bp product for group B wild-type strains, a 279-bp product for 2B strains, a 547-bp product for all group A strains, and an additional 688-bp product for some group A strains, including 3A strains. These types of PCR assays can, in conjunction with other methods, be used to efficiently distinguish candidate vaccine strains from other respiratory syncytial virus strains.
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2159
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Effect of quantum lattice fluctuations on the optical-absorption spectrum of degenerate and nondegenerate polymers. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:3107-3112. [PMID: 9983818 DOI: 10.1103/physrevb.53.3107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2160
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Abstract
To understand the in vivo function of the amyloid precursor protein (APP) we generated an APP null mutation in mice by homologous recombination in embryonic stem (ES) cells. We show here that homozygous APP deficient mice were produced at expected frequencies. Neither APP mRNA nor protein could be detected in these animals. Yet the homozygous APP mutant mice are fertile and do not show overt abnormalities at up to 12 weeks of age. Neuroanatomical studies of the brain did not reveal significant differences in the knockout mice as compared to the wild-type controls. These results argue against an essential function of APP in mouse embryonic and early neuronal development.
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2161
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Abstract
Amyloid precursor proteins (APP) are a member of a larger family of proteins that include the amyloid precursor-like proteins (APLP) APLPI and APLP2. We have examined the expression and metabolism of APLP2 and document that APLP2 is expressed at high levels in the nervous system and in peripheral tissues. Furthermore, several APLP2 isoforms encoded by alternatively spliced transcripts are posttranslationally modified by a chondroitin sulfate glycosaminoglycan (CSGAG) chain. Furthermore, CSGAG modification is regulated by the insertion of sequences encoded by an alternatively spliced exon. Notably, expression of the CSGAG form of APLP2 appears restricted to embryonic neurons and mature neuronal populations that undergo regeneration, such as olfactory sensory neurons. Thus, differences in posttranslational modifications between the APLP2 isoforms and APP are likely to underlie differences in the regulation and function of these homologues. Our present efforts are directed towards using gene targeting strategies to disrupt the expression of the mouse APP/APLP2 genes to define the normative roles of the encoded molecules in development, plasticity, regeneration, and repair.
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2162
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[Laryngeal reinnervation by nerve-muscle multipedicle transfer]. ZHONGHUA ER BI YAN HOU KE ZA ZHI 1996; 31:29-32. [PMID: 9275400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Abductive ability was restored by means of a modified nerve-muscle pedicle technique, utilizing nerve-muscle multipedicle and multipoint implantation in seventeen dogs. The results showed that the procedure was superior to traditional Tucker's technique in functional recovery, electrophysiological activity and muscle strength which was also demonstrated by histochemical studies. There was little difference between double and three nerve-muscle pedicle transfer. The procedure has been used in three patients with bilateral vocal cord paralysis. Return of spontaneous abduction in the operated side in two patients was noted after eight and twelve weeks after surgery. All patients have achieved sufficient airway without the need of tracheotomy. Electromyography confirmed the reinnervation of posterior cricoarytenoid muscle.
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2163
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Spontaneous breaking of vector symmetries and the nondecoupling light Higgs particle. Int J Clin Exp Med 1995; 52:6500-6504. [PMID: 10019192 DOI: 10.1103/physrevd.52.6500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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2164
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Long-range electron-phonon correlation and Peierls dimerization in the one-dimensional molecular-crystal model. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:15261-15272. [PMID: 9980881 DOI: 10.1103/physrevb.52.15261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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2165
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Thermal and behavioral effects of lipopolysaccharide and influenza in interleukin-1 beta-deficient mice. THE AMERICAN JOURNAL OF PHYSIOLOGY 1995; 269:R969-77. [PMID: 7503324 DOI: 10.1152/ajpregu.1995.269.5.r969] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This study characterized body temperature (Tb), locomotor activity (Act), and feeding behavior under normal conditions and following injection with lipopolysaccharide (LPS) or inoculation with live influenza virus of transgenic C57/black mice deficient in interleukin-1 beta (IL-1 beta). Tb and Act in freely moving mice were measured by biotelemetry. Mice deficient in IL-1 beta had normal circadian rhythm of Tb but were less active than their control counterparts. Mice injected with LPS (2.5 mg/kg i.p.) responded with a prompt decrease of Tb, which lasted approximately 10 h, followed by a fever in which Tb reached a peak at approximately 24 h postinjection. There was no difference between groups in the early drop of Tb after the LPS; however, the 24-h peak of Tb was lower in IL-1 beta-deficient mice. The anorexic effects of LPS and influenza infection were similar in both groups of mice. In mice given influenza virus (17.5 plaque-forming units, median lethal dose), Tb and Act gradually decreased. The fall of Tb was smaller in the transgenic mice. The mice deficient in IL-1 beta displayed a higher mortality rate due to influenza infection than the control mice. We conclude that deficiency in IL-1 beta results in lower fever following the LPS injection and in impairment of the defense response to infection with influenza.
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2166
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[Ultrastructural changes in pulmonary microvascular damage in rats inflicted with burn, blast and combined burn-blast injury]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1995; 11:425-9. [PMID: 8728929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The pathological changes in pulmonary microvasculature in rats inflicted with overpressure blast, 15% third degree burns and combined burn-blast injury, respectively, were studied with electron microscopy and ultrastructural morphometry. Results indicated that the pathological changes in pulmonary microvasculature in 15% third degree burns were slight, and mainly restricted to ultrastructural level. While in severe blast and burn-blast injuries, the damage of pulmonary microvasculature including endothelial swelling and regeneration and dispersal of arteriole wall structure, was prominent. These changes form the basis of pulmonary hemorrhage and edema. Apart from vessel structural damages, arteriole constriction and capillary closure were also observed during 2 to 4 h postinjury. The vessel damage and dysfunction were more severe in combined injury than in blast injury alone. The mechanisms needed to be studied further.
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2167
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Abstract
We examined the genomic variability of 26 wild-type 1 polioviruses isolated from 12 provinces in China from 1985-1993. The poliovirus genome region that encodes the N-terminal portion of the VP1 protein was amplified by the polymerase chain reaction (PCR). The PCR product of each isolate was analysed by restriction fragment length polymorphism (PCR-RFLP) and by direct sequencing. Several groups of viruses with different PCR-RFLP patterns were found to cause outbreaks in China during this period. Viruses with identical PCR-RFLP profiles were dominantly isolated in 11 provinces from 1991 to 1993 and were considered to be the major epidemic strain in China. On the other hand, in the GuangDong province, a different group was responsible for each year's outbreak, while in the XinJiang autonomous prefecture, a single strain was consistently isolated from 1990 to 1993. Understanding of the nationwide distribution of wild poliovirus is very important for interrupting its transmission during the final stage of the eradication program in China.
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2168
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Nasal natural killer (NK) cell lymphoma: report of a case with activated NK cells containing Epstein-Barr virus and expressing CD21 antigen, and comparative studies of their phenotype and cytotoxicity with normal NK cells. Br J Haematol 1995; 91:355-61. [PMID: 8547075 DOI: 10.1111/j.1365-2141.1995.tb05303.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Malignant lymphomas arising from the nasal cavity have been considered to be derived from T cells, but recent surface marker studies suggest that more than half of the lymphomas are derived from natural killer (NK) cells. Here we describe a case of nasal lymphoma whose lymphoma cells were identified as NK cells by morphological, phenotypic, immunogenotypic, and functional studies. We believe this is the first study with functional evidence of NK activity. When compared with normal freshly isolated NK cells or activated NK cells, the surface phenotypes and NK activity of the patient tumour cells were those of the activated, but not resting, NK cells. Also, Epstein-Barr virus (EBV) was detected in the tumour cells and the lymphoma cells were found to be monoclonally expanded. The patient's lymphoma cells also expressed EBV receptor CD21 (CR2) and CD30 (Ki-1) that have not been described on normal NK cells. We therefore examined highly enriched NK cells of normal donors, and found that some resting and/or activated NK cells express these antigens.
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2169
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[Textual study and resource investigation on traditional Chinese drugs duhuo, jiuyanduhuo and qianghuo]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1995; 20:515-7, 574. [PMID: 8679086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
By means of Bencaological study on traditional Chinese drugs Duhuo, Jiuyanduhuo and Qianghuo, it has been found out that the Duhuo recorded in earlier Bencao works should be Qianghuo, and Duhuo was first used medically in the South-North Dynasty period, whereas Jiuy-anduhuo's medical use started in the Ming Dynasty. Resources of the three drugs were investigated and their main species were found out.
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2170
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High expression of synthetic human interferon-gamma cDNA in E. coli. SCIENCE IN CHINA. SERIES B, CHEMISTRY, LIFE SCIENCES & EARTH SCIENCES 1995; 38:1084-93. [PMID: 8554677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Human interferon-gamma (IFN-gamma) cDNA was synthesized, and it makes the usage of favorable codons in E. coli. The authors got 9 different expression plasmids which contain the synthetic IFN-gamma-cDNA and have different spaces between SD sequence and ATG. The free energies G0f298 in the formation of stable secondary structure in the translation initiation region (TIR) are different in various expression plasmids. One of them, pLY4-gamma 5, can highly yield INF-gamma which will be about 60%-80% of the total bacterial proteins, such a high expression was hardly noted in literature. The reasons of high expression in this work are optimal spaces between SD and ATC, favorable delta G0f298, favourable condons usage for E. coli.
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2171
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Abstract
Metallothioneins (MTs) are sulfhydryl-rich proteins. MT-I and MT-II are found in all tissues of the body, while MT-III exists only in brain. Regulation of MT-I and MT-III mRNA was studied in brain and liver of control C57BL/6J mice and mice given chemicals known to increase MT-I, namely, lipopolysaccharide (LPS), zinc chloride (Zn), cadmium chloride (Cd), dexamethasone (Dex), ethanol, and kainic acid (KA). Northern blot analysis revealed that MT-I mRNA levels in liver were induced dramatically (12-27-fold over basal levels) by all of the chemicals, while in brain only LPS produced an increase in MT-I mRNA (2-fold). Interestingly, the MT-I inducers, Cd, Dex, ethanol, and KA, down-regulated brain MT-III mRNA levels by approx. 30%. Because brain is such a heterogenous tissue, in situ hybridization was used to localize MT-I and MT-III mRNA in control and treated mice. MT-I mRNA signal, which was most abundant in the glial cells of the Purkinje cell layer of the cerebellum in control mice, appeared to be enhanced in mice given the MT-I inducers (LPS, Zn, Cd, Dex, ethanol, and KA). MT-I mRNA hybridization signal was also enhanced in the olfactory bulbs from LPS- and Cd-treated mice, while this signal was present but weak in control brains. MT-III mRNA hybridization signals were localized in hippocampus and co-localized with MT-I message in the glial cells of the Purkinje cell layer of the cerebellum. In addition, diffuse MT-III mRNA signals were visible in areas of the cerebral cortex, and in the molecular layer of the cerebellum. Signals for MT-III in hippocampus appeared to be reduced by KA, Dex and LPS treatment, while in the cortical region, MT-III mRNA signals appeared to be enhanced by KA, Cd, and ethanol treatment. In conclusion, both MT-I and MT-III expression in brain appears to be modulated by exogenous treatment, however, the changes are small in relation to those observed in liver. Chemical-induced alterations of MT mRNA are non-uniform throughout the brain, and thus best studied in a region-specific manner.
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2172
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Abstract
We used gene targeting in embryonic stem cells to introduce an IL-1 beta null allele in mice. The IL-1 beta-deficient mice develop normally and are apparently healthy and fertile. The IL-1 beta null mice responded normally in models of contact and delayed-type hypersensitivity or following bacterial endotoxin LPS-induced inflammation. The IL-1 beta-deficient mice showed equivalent resistance to Listeria monocytogenes compared with wild-type controls. In contrast, when challenged with turpentine, which causes localized inflammation and tissue injury, the IL-1 beta mutant mice exhibited an impaired acute-phase inflammatory response and were completely resistant to fever development and anorexia. These results highlight a central role for IL-1 beta as a pyrogen and a mediator of the acute-phase response in a subset of inflammatory disease models, and support the notion that blocking the action of a single key cytokine can alter the course of specific immune and inflammatory responses.
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2173
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[A study on the viability of corneal endothelium in rabbit by dual staining with trypan blue and alizanin red S]. YAN KE XUE BAO = EYE SCIENCE 1995; 11:65-69. [PMID: 9208653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
PURPOSE We study the viability of preserved rabbit corneal endothelium by dual staining with trypan blue and alizanin red S. METHOD We randomly divided New Zealand white rabbit eyes into four groups, each with 5 eyes. The eye balls were preserved in moist chambers with aqueous remorad and C3F8 temponade for 5, 7, 10 and 14 days. Then we got the corneal Bottons with sclera ring. Isolated corneas were placed with the endothelial side up in a corneal cup, and trypan blue (0.25%) was added drop-wise to cover the endothelium. After 1.5 minutes the stain was poured out. The endothelial layer was then covered with aliznin red S (0.2%) for 1.5 minutes and pouring away the staining reagent. After staining, the corneas were immensec in glutaraldehyde fixative solution for 10 minutes. Finally, the endothelium was examinated and taken photoes with light microscope. RESULTS Changed cells that have become permeable to trypan blue show deep blue staining of their nuclei in contrast to the unstained condition of normal cells. All the intercellular borders of endothelial cells were purple. The survival rate of the endothelium preserved for 5 and 7 day is more than 95%, for 10 days is 75-80%, and for 14 days about 70%. CONCLUSION This technique allows a proportion cout of damaged and undamaged cells in the endothelial monolayer, makes it possible to observe their structures clearly and gives advantage to take pathelage photos.
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2174
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Abstract
In several pedigrees of early onset familial Alzheimer's disease (FAD), point mutations in the beta-amyloid precursor protein (APP) gene are genetically linked to the disease. This finding implicates APP in the pathogenesis of Alzheimer's disease in these individuals. To understand the in vivo function of APP and its processing, we have generated an APP-null mutation in mice. Homozygous APP-deficient mice were viable and fertile. However, the mutant animals weighed 15%-20% less than age-matched wild-type controls. Neurological evaluation showed that the APP-deficient mice exhibited a decreased locomotor activity and forelimb grip strength, indicating a compromised neuronal or muscular function. In addition, four out of six homozygous mice showed reactive gliosis at 14 weeks of age, suggesting an impaired neuronal function as a result of the APP-null mutation.
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2175
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Motion-based object segmentation and estimation using the MDL principle. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1995; 4:1223-1235. [PMID: 18292019 DOI: 10.1109/83.413167] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
There are increasing demands for ultralow bit-rate video image transmission. We present a new formulation of moving object segmentation and motion estimation to quantify the potential gain in using object-oriented motion compensation in image sequence coding. Motivated by real-valued parameter estimation required in object-oriented motion-compensated video source coding, a framework motivated by Rissanen's (1983) minimum description length (MDL) principle is proposed to more tightly couple motion estimation and object segmentation algorithms to the overall objective of minimizing source bit rate. A new objective function is constructed, and a suboptimal procedure to segment and estimate moving objects in a scene is proposed. Each object is represented by chain-coded block boundaries, affine motion parameters, and motion-compensated prediction error. A number of experimental comparisons between block- and object-oriented coding schemes suggests a significant potential coding gain using object-oriented motion-compensated coding.
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2176
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Low energy properties of the heavy vector fermions and electroweak symmetry breaking. Int J Clin Exp Med 1995; 51:251-259. [PMID: 10018292 DOI: 10.1103/physrevd.51.251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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2177
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Abstract
We report the purification of a protease from tumor cells undergoing apoptosis that is involved in activating DNA fragmentation. Initial studies revealed that two inhibitors of serine proteases, N-1-tosylamide-2-phenylethylchloromethyl ketone and carbobenzoxy-Ala-Ala-borophe (DK120), suppressed tumor necrosis factor or ultraviolet (UV) light-induced DNA fragmentation in the U937 histiocytic lymphoma as well as UV light-induced DNA fragmentation in the BT-20 breast carcinoma, HL-60 myelocytic leukemia, and 3T3 fibroblasts. The protease was purified by affinity chromatography with DK120 as ligand and showed high activity on a synthetic substrate preferred by elastase-like enzymes (Ala-Ala-Pro-Val p-nitroanilide), but was inactive on the trypsin substrate, N-alpha-benzyloxycarbonyl-L-lysine thiobenzyl ester, or the chymotrypsin substrate, Ala-Ala-Pro-Phe p-nitroanilide. The activity of the DK120-binding protease purified from U937 cells undergoing apoptosis was increased approximately 10-fold over that recovered from normal cells. Further purification to homogeneity by heparin-Sepharose affinity chromatography followed by reverse phase high-performance liquid chromatography revealed a single band of 24 kD on a silver-stained sodium dodecyl sulfate gel. In addition to protease activity, the purified enzyme induced DNA fragmentation into multiples of 180 basepairs in isolated U937 nuclei. These findings suggest the 24-kD protease is a novel enzyme that activates DNA fragmentation in U937 cells undergoing apoptosis.
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2178
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Abstract
This paper describes a potential hazard in obtaining sequences of a multigene family by amplifying the mixed population by the polymerase chain reaction with primers from conserved sequences. We describe a product which appears to be a chimera formed during the PCR reaction from two different but related sequences.
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2179
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Variational approach to the quantum lattice fluctuations in the Su-Schrieffer-Heeger model: The ground state. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:6717-6725. [PMID: 9974624 DOI: 10.1103/physrevb.50.6717] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2180
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[A prospective study on the relationship between body mass index and mortality from all causes in 15,827 middle aged and elderly citizens]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1994; 15:199-202. [PMID: 7834701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The association between Body Mass Index (BMI) and mortality from all causes was investigated in a cohort study of 15827 citizens (aged 35 and over) in Shanghai. During about 3-year follow up the person-year mortality for men and women were 1311.78/100000 and 1036.87/100000, respectively. Cox regression analysis was conducted in a lower and an upper range of BMI, respectively. The inverse association between BMI and mortality in the lower range was statistically significant for men and women. The positive association between BMI and mortality in the upper range was highly statistically significant for women but not for men. Logistic regression analysis conducted over the entire range of BMI showed that BMI and all-cause mortality association was significantly "L"-shaped distribution for men and women. The mortality or relative hazard curve can be fit with quadratic model (Y = a-bX + cX2) in different sex.
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2181
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Exclusion of ferritins and iron-responsive element (IRE)-binding proteins as candidates for the hemochromatosis gene. Hum Genet 1994; 94:159-64. [PMID: 8045562 DOI: 10.1007/bf00202862] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have looked for genes for ferritin and its translational control protein that could account for anomalies in the expression of ferritin (FT) and the transferrin receptor in the duodenum of individuals with hemochromatosis (HC). We show that there are probably only two FTH-like sequences near the HC locus on the short arm of chromosome 6 and no FTL-like sequences. We report the cloning of the previously uncharacterized FTH sequence from 6p (FTHL15) and show that it is probably a processed pseudogene. This gene has been mapped with a panel of radiation hybrid cells to near 6p12. Additionally, we show that there are no sequences on chromosome 6p for a protein that coordinately regulates expression of ferritin and the transferrin receptor.
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2182
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Transitions from conventional metals and insulators to Kondo metals and insulators. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:1369-1375. [PMID: 9976321 DOI: 10.1103/physrevb.50.1369] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2183
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[Clinicopathological analysis of rhabdomyosarcoma of the ocular adenexa]. YAN KE XUE BAO = EYE SCIENCE 1994; 10:125-8, 120. [PMID: 7843394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
12 cases including 11 males and 1 female of rhabdomyosarcoma of ocular adenexa were analysed. The average age of the patients was 4.2 years. 9 cases of lesion were located in the orbit, 2 in the eyelid and 1 in conjunctiva. Pathologically 8 cases were embryonal forms, 2 alveolar, 2 polymorphic. Immunohistochemical studies were performed in 8 cases, which showed desmin positive. Myoglobin presented strong or weak positive in 5 cases, suspicious positive in 3 cases. The clinical manifestation, prognosis and treatment were briefly discussed.
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2184
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Abstract
We evaluated the usefulness of a recombinant parasite antigen (recSXP1) for the serologic diagnosis of lymphatic filariasis. A large proportion of sera from microfilaremic donors living in five different endemic countries (356 of 446 [80%]) contained IgG antibodies to recSXP1, as do sera from approximately 33% of amicrofilaremic patients with acute filarial disease and/or indirect evidence of active filarial infection. Exposure to filarial worms per se does not appear sufficient to elicit an anti-SXP1 antibody response. Thus, this serologic test identifies a large proportion of persons with active lymphatic filariasis among residents of endemic areas.
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2185
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[Nasal NK-cell lymphoma]. [RINSHO KETSUEKI] THE JAPANESE JOURNAL OF CLINICAL HEMATOLOGY 1994; 35:588-92. [PMID: 8078194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A 75-year-old man was admitted to our hospital on June 1st, 1993, because of nasal obstruction, epistaxis, fever, night sweats and weight loss. Examination disclosed a 2-cm white necrotic mass in the nasal septum, and a biopsy disclosed non-Hodgkin's lymphoma, diffuse, mixed-type. Imprint smears showed cytoplasmic azurophilic granules in the tumor cells. Dense granules were demonstrated by electron microscopy. The tumor cells were CD1-2+3-4-7+8-16+56+57-, and T cell receptor genes were in germline configuration. NK activity against K562 was strongly positive. Based on morphologic, phenotypic, immunogenotypic, and cytotoxic findings, the tumor cells seemed to be derived from activated NK cells. Because the tumor cells were positive for the EB virus and CD21 antigen, EB virus seemed to have infected CD21-positive NK cells and transformed them. MDR P-glycoprotein was also positive. This finding may explain why nasal lymphomas are resistant to chemotherapy and have a poor prognosis.
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2186
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[Intravenous placental immunoglobulin for treatment of chronic graft versus host disease]. ZHONGHUA NEI KE ZA ZHI 1994; 33:306-8. [PMID: 7835140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Intravenous placental immunoglobulin (IV Pt IG) was used for the treatment of chronic graft versus host disease (CGVHD) in 30 patients who are refractory to steroid and cyclosporinic A. 15 (50%) patients showed excellent response and 11 (36.66%) good response. The total response rate is 86.66%. The dosage of IV Pt IG was 4 gm/day in adults by intravenous infusion. Effectiveness of IV PtIG was discerned within 2 weeks. The plasma levels of IgG, IgA and IgM were tested before and after IV PtIG treatment. There was no significant statistical difference between the plasma IgG, IgA, IgM levels in pre- and post-treatment period. The efficacy of IV PtIG against CGVHD is therefore ascribed to its pharmacological effect.
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2187
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Effect of quantum-lattice fluctuations in one-dimensional fluctuating-valence systems. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:9539-9547. [PMID: 10009751 DOI: 10.1103/physrevb.49.9539] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2188
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[Application of synthetic 27 oligopeptide of HDV antigen for detecting serum anti-HD in HBV infected subjects in Chongqing]. ZHONGHUA NEI KE ZA ZHI 1994; 33:237-40. [PMID: 7956561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A synthetic HDAg 27 peptide which was selected and designed by the authors and synthesised by Shanghai Institute of Biochemistry, Chinese Academy of Science was used with ELISA method to detect serum anti HD in HBV infected subjects in Chongqing. Anti HD was positive in one of 300 blood donors and was negative in all of 113 cases of hepatitis A and 58 cases of hepatitis non-B. Anti HD was positive in 106 out of 882 cases with positive HBV marker (12.02%), among which anti HD was positive in 3.17% (13/410) of HBsAg carrier, 14.4% (11/76) of acute hepatitis, 7.6% (1/13) of chronic persistent hepatitis, 17.68% (22/121) of chronic active hepatitis, 19.77% (17/86) of severe hepatitis, 29.49% (23/78) of liver cancer and 19.39% (19/98) of primary hepatic cancer. These results coincided with those of previous reports. The coincidence rate was 94.9% (74/78) when compared with Abbott EIA kit. When the natural HDAg was used to compete anti HD in four anti HD positive and two anti HD negative serum specimens, anti HD was negative in all specimens. It is shown that the HDAg 27 peptide has natural HDAg activity capable of being recognized by natural anti HD and is a new diagnostic agent being more simple, save, stable and reliable.
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2189
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[A community cohort study on risk factors of strokes in Shanghai: a Cox regression analysis on 15,885 subjects]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1994; 15:94-8. [PMID: 7923341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Baseline investigation on 15,885 subjects who were over thirty-five years old had been launched since July 1987. All of them were selected from eighteen neighbourhoods of three districts in Shanghai by using multiple stage cluster sampling procedure. All of them were followed up till the end of 1989. Each new case of stroke was randomly matched with about twenty controls by age and sex. The total 2,682 controls together with 127 new cases of strokes were analyzed by using Cox regression model for risk factors. The population attributable risk proportion (PARP) of factors was also estimated.
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2190
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Variational treatment of retarded phonon-induced electron pairing. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:9763-9773. [PMID: 10009776 DOI: 10.1103/physrevb.49.9763] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2191
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[Cloning and DNA sequencing of the gene encoding trichosanthin]. YI CHUAN XUE BAO = ACTA GENETICA SINICA 1994; 21:42-51. [PMID: 8003348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A gene encoding Trichosanthin (TCS) was amplified by means of DNA polymerase chain reaction (PCR) and cloned from the genomic DNA of Trichosanthes kirilowii. Its DNA sequence has been determined. Nucleotide sequence analysis indicates that the cloned TCS gene includes 5'-flanking region and the encoding sequence for TCS preproprotein. Comparison of its encoding sequence with the published nucleotide sequences of three TCS genes demonstrates that they have the sequence homologies of 99.20%, 98.74% and 98.64% respectively. Comparing its deduced amino acid sequence with four reported amino acid sequences of TCS demonstrates that they have the sequence homologies of 98.62%, 97.62%, 97.41% and 98.38% respectively. A new TATA-like box sequence was found in the 5'-flanking region of cloned TCS gene. In order to further study the structure, expression, regulating mechanism of TCS gene and the structure-functional relationship of TCS, a series of mutants of TCS gene has been constructed. The expression of these mutants in bacteria and transgenic plant has being studied.
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2192
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[Experimental study on delayed reinnervation of vocal cord adductors]. ZHONGHUA ER BI YAN HOU KE ZA ZHI 1994; 29:218-220. [PMID: 7803121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The adductor branch was anastomosed with the main branch of ansa cervicalis to reinnervate the vocal cord adductors in six dogs at the time of denervation and after varying intervals of chronic denervation. Some recovery of adduction was noted within ten-month interval. Laryngeal electromyography, tension tests and histologic studies of the adductor muscles were correlated with the recovery of adduction. Although adduction didn't recover after twelve-month interval, striations of the adductor muscles were normal, only slight fibrosis was observed.
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2193
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A novel granulocyte-derived peptide with lipopolysaccharide-neutralizing activity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1994; 152:231-40. [PMID: 8254193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Rabbit CAP18 (cationic antimicrobial protein, 18 kDa) is a leukocyte protein identified and purified using as an assay its capacity to bind and inhibit various activities of LPS. Oligonucleotide probes designed from the putative N-terminal protein sequence were used to obtain the corresponding cDNA from a rabbit bone marrow cDNA library. Examination of the cDNA sequence revealed that the protein fragment of the putative N-terminus was actually a 37-amino-acid C-terminal fragment. This fragment, designated CAP18(106-142), inhibits many activities of LPS. In the present studies, synthetic CAP18(106-142) is shown to: 1) bind to erythrocytes coated with diverse strains of LPS; 2) inhibit LPS-induced release of cytokines (TNF, IL-1, IL-6) and nitric oxide from macrophages; 3) inhibit LPS-induced LAL coagulation and 4) protect mice from LPS lethality. CAP18(106-142) may have therapeutic utility for conditions associated with elevated concentrations of LPS.
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2194
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Abstract
Primary rat gastric cell cultures were investigated as an in vitro model for evaluating antiulcer agents. Following exposure to concentrations of up to 5 mg/mL of an antiulcer agent sucralfate, an aluminum hydroxide complex of sucrose octasulfate, cultured cells were treated with either pH 3.5 medium or 3.5 mM indomethacin. Cytoprotection was evaluated by colony forming efficiency, neutral red uptake, and 3-(4,5-dimethyl-2-thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) hydrolysis. By each measure, and depending on damaging agent, 2 and 5 mg/mL sucralfate provided partial (50% of untreated control) to near-complete (90% of untreated control) cytoprotection, respectively. Aluminum hydroxide also provided partial (55% of untreated control) to near-complete (more than 90% of untreated control) cytoprotection at 2 and 5 mg/mL, respectively, for the pH 3.5 medium-induced damage. Over a concentration range of 0.05 to 5 mg/mL, the potassium salt of sucrose octasulfate, KSOS, stimulated cell growth up to 40-60% over untreated controls but had little or no cytoprotective action in the presence of either 3.5 mM indomethacin or pH 3.5 medium. Overall results suggested that sucralfate may have at least two roles in influencing gastric epithelial cell function, cytoprotection and stimulation of cell growth in vitro. These observations serve as a basis for further study of in vitro models in evaluating the cytoprotective activity of antiulcer agents and their respective mechanisms of action.
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2195
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A novel granulocyte-derived peptide with lipopolysaccharide-neutralizing activity. THE JOURNAL OF IMMUNOLOGY 1994. [DOI: 10.4049/jimmunol.152.1.231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Rabbit CAP18 (cationic antimicrobial protein, 18 kDa) is a leukocyte protein identified and purified using as an assay its capacity to bind and inhibit various activities of LPS. Oligonucleotide probes designed from the putative N-terminal protein sequence were used to obtain the corresponding cDNA from a rabbit bone marrow cDNA library. Examination of the cDNA sequence revealed that the protein fragment of the putative N-terminus was actually a 37-amino-acid C-terminal fragment. This fragment, designated CAP18(106-142), inhibits many activities of LPS. In the present studies, synthetic CAP18(106-142) is shown to: 1) bind to erythrocytes coated with diverse strains of LPS; 2) inhibit LPS-induced release of cytokines (TNF, IL-1, IL-6) and nitric oxide from macrophages; 3) inhibit LPS-induced LAL coagulation and 4) protect mice from LPS lethality. CAP18(106-142) may have therapeutic utility for conditions associated with elevated concentrations of LPS.
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2196
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Abstract
A cationic antimicrobial protein of 18 kDa (CAP18) was originally isolated from rabbit granulocytes by using as an assay the agglutination of Re-lipopolysaccharide-coated erythrocytes. The C-terminal 37 amino acids of CAP18 (CAP18(106-142)) make up the lipopolysaccharide-binding domain. Synthetic CAP18(106-142) has broad antimicrobial activity against both gram-positive (50% inhibitory concentration, 130 to 200 nM) and gram-negative (50% inhibitory concentration, 20 to 100 nM) bacteria. Susceptible strains include Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhimurium. Antimicrobial activity is highly dependent on peptide structure. Although a 32-amino-acid peptide resulting from the truncation of 5 amino acids from the C terminus of CAP18(106-142) is highly active, other fragments of CAP18(106-142), including CAP18(106-142) with a truncated N terminus, do not exhibit antimicrobial activity. Unlike previously characterized antimicrobial peptides derived from granulocyte proteins, CAP18(106-142) is active in serum. CAP18(106-142) or a derivative peptide may have therapeutic potential for bacterial sepsis.
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2197
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Self-consistent cluster-embedding calculation method and the calculated electronic structure of NiO. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:14868-14883. [PMID: 10008018 DOI: 10.1103/physrevb.48.14868] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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2198
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Role of protein phosphorylation in TNF-induced apoptosis: phosphatase inhibitors synergize with TNF to activate DNA fragmentation in normal as well as TNF-resistant U937 variants. J Cell Biochem 1993; 53:222-33. [PMID: 8263039 DOI: 10.1002/jcb.240530307] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study examined the role of protein phosphorylation in TNF induction of apoptosis in several tumor cell lines by testing the effects of agents that either stimulate or inhibit protein phosphorylation. The serine-threonine phosphatase inhibitors, okadaic acid (OKA) and calyculin A (CLA), synergistically augmented TNF-induced apoptosis in several TNF-sensitive tumor cell lines including the U937 histiocytic lymphoma, the BT-20 mammary carcinoma, and the LNCap prostatic tumor cell line. Furthermore, the phosphatase inhibitors completely reversed the TNF resistance of a variant (U9-TR) derived from U937. CLA also inhibited phosphatase activity in cell-free extracts from both U937 and U9-TR at the same concentrations (0.4-2.0 nM) that it synergized with TNF. In contrast, TNF treatment of U937 cells did not result in inhibition of phosphatase activity mediated by protein phosphatase 1 (PP1) and PP2A in cell extracts. Since the phosphatase inhibitors are known to increase the overall levels of protein phosphorylation in cells, this suggested that TNF may act by stimulating protein kinase (PK) activity. This hypothesis was supported by the results of testing a panel of relatively specific protein kinase inhibitors. TNF activation of DNA fragmentation was blocked by a potent inhibitor of myosin light chain kinase (MLCK) but was unaffected by inhibitors of cAMP or cGMP-dependent PKs. We postulate that a defect in the activation of MLCK or possibly some other as yet unknown PK may be responsible for the TNF resistance of U9-TR. Furthermore, this resistance may be circumvented by promoting protein phosphorylation with the serine-threonine-dependent phosphatase inhibitors.
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2199
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Nicotine inhibition of apoptosis suggests a role in tumor promotion. FASEB J 1993; 7:1045-51. [PMID: 8370474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Recent evidence indicates that cell death through apoptosis may be an important mechanism to prevent tumor development. Therefore, agents that inhibit apoptosis may function as tumor promoters. The purpose of this study was to determine the effects of nicotine on the process of apoptosis. The results demonstrate that nicotine inhibits apoptosis induced by diverse stimuli including tumor necrosis factor (TNF), UV light, chemotherapeutic drugs, and calcium ionophore. This phenomenon was observed in normal and transformed cells derived from a variety of species and tissues, including tumor cell types related to tobacco use. The major nicotine metabolite, cotinine, also inhibited apoptosis, whereas N-nitrosodiethylamine, a carcinogen found in tobacco, was without effect. Therefore, nicotine-mediated inhibition of apoptosis may contribute to the pathogenesis of tobacco-related cancer as well as decrease the efficacy of cancer therapies.
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2200
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[Analysis of estrogen receptors in normal bone and bone tumor tissues]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1993; 24:160-2. [PMID: 8244293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Thirteen human normal bone and fifteen bone tumor tissues were assayed for estrogen receptor (ER) by Dextran-coated Charcoal method (Scatchard plot). The results showed that the concentrations of ER in normal bone tissues (15.12 +/- 14.68 fmol/mg pro) were higher than that of bone malignant tumors (8.04 +/- 6.71 fmol/mg pro) P < 0.05). The binding dissociation constants (Kd) of ER in bone tumors (18.46 +/- 27.10 x 10(-11) mol/L) was lower than those in normal ones (39.91 +/- 20.13 x 10(-11) mol/L) (P < 0.025). The percentages for positive score of ER in normal and tumor ones (23.1%, 26.7%) were not significantly different (P > 0.05). Our study indicated that the variations of concentration and affinity of ER in bone related to the tumor incidence. That cytosol ER content was decreased in malignant bone tumors whereas that of affinity increase suggests an impairment or change of an intact receptor mechanism in this tissues.
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