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Bai F, Matsui T, Ohtani-Fujita N, Matsukawa Y, Ding Y, Sakai T. Promoter activation and following induction of the p21/WAF1 gene by flavone is involved in G1 phase arrest in A549 lung adenocarcinoma cells. FEBS Lett 1998; 437:61-4. [PMID: 9804172 DOI: 10.1016/s0014-5793(98)01198-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Flavonoids are present in many plants including edible fruits and vegetables. Recently, many of the biological activities of flavonoids have been elucidated. Flavone is a well known flavonoid, and many of its derivatives have been shown to have anti-proliferative effects on several cancer cells. We report here that flavone can effectively inhibit the cell growth of human lung adenocarcinoma A549 cells in a dose-dependent manner, and 100 microM flavone causes cell cycle arrest at the G1 phase. As a mechanism underlying the cell cycle arrest, flavone markedly increases the mRNA and protein levels of a universal inhibitor of cyclin-dependent kinase, p21/WAF1, and inhibits phosphorylation of retinoblastoma (RB) protein. Although A549 cells possess wild-type p53, flavone does not induce the p53 protein, suggesting that p21/WAF1 induction is p53-independent. In addition, 100 microM flavone significantly increases the promoter activity of the p21/WAF1 gene by 5-fold. These results suggest that the G1 phase arrest by flavone is due to p53-independent transcriptional induction of the p21/WAF1 gene and the subsequent dephosphorylation of RB protein.
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Pei XH, Nakanishi Y, Takayama K, Bai F, Kawasaki M, Hara N. G-CSF increases secretion of urokinase-type plasminogen activator by human lung cancer cells. Clin Exp Metastasis 1998; 16:551-8. [PMID: 9872602 DOI: 10.1023/a:1006546402703] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We reported previously that granulocyte colony-stimulating factor (G-CSF) can promote the invasion of human lung cancer cell lines in vitro. However, the exact mechanism of its stimulatory effect on invasion remains to be elucidated. In the present study we mainly focused our attention on the components of the plasminogen activation system in human lung cancer cell lines, because of the central role that plasminogen activators play in regulating extracellular proteolysis. We showed that G-CSF induced a dose-dependent increase in the urokinase-type plasminogen activator (uPA) activity in the conditioned medium of a PC-9 lung cancer cell line. When the amounts of uPA activity were quantitated by densitometry, we found that even at a concentration of 0.01 microg/ml, G-CSF had a stimulatory effect on the uPA release, while high concentrations caused a 3.6-fold increase at a maximum concentration of 1 microg/ml. A Western blot analysis of the conditioned medium confirmed the findings observed in a zymographic analysis. The observed increase in uPA protein was paralleled by a significant increase in the uPA mRNA levels after treatment with G-CSF. However, our experiments failed to identify any alteration in the plasminogen activator inhibitor (PAI) secretion caused by G-CSF. In addition, we also found the expression of G-CSF receptor by PC-9 cells, suggesting the possible pathway activated by G-CSF.
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Bai F, Nakanishi Y, Takayama K, Pei XH, Tokiwa H, Hara N. Ki-ras mutation and cell proliferation of lung lesions induced by 1-nitropyrene in A/J mice. Mol Carcinog 1998; 22:258-64. [PMID: 9726818 DOI: 10.1002/(sici)1098-2744(199808)22:4<258::aid-mc7>3.0.co;2-f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In this study, lung lesions were found in male A/J mice 24 wk after intraperitoneal injection of 1-nitropyrene (1-NP). The lesions were classified into three categories: alveolar/bronchiolar hyperplasia, adenoma, and adenocarcinoma. The proliferation kinetics of cells in the lesions were evaluated by assessing proliferating cell nuclear antigen (PCNA) expression and silver-staining nucleolar organizer regions (AgNORs). Furthermore, the role of the Ki-ras gene in tumorigenesis was studied by detecting point mutations in Ki-ras codons 12, 13, and 61 by polymerase chain reaction and sequence analysis. The PCNA-positive rates (+/- standard deviations) in various samples were as follows: 0% for specimens from six untreated animals and six uninvolved areas, 4.26 +/- 3.94% for 19 hyperplasias (hyperplasias vs normal lung tissue, P < 0.01), 13.24 +/- 6.35% for 25 adenomas (adenomas vs hyperplasias, P < 0.01), and 38.0 +/- 9.63% for four adenocarcinomas (adenocarcinomas vs adenomas, P < 0.01). The corresponding mean AgNOR scores were as follows: 1.10 +/- 0.05 for the untreated animals, 1.32 +/- 0.09 for the uninvolved areas, 1.72 +/- 0.59 for the hyperplasias (hyperplasias vs normal lung tissue, P > 0.05), 2.74 +/- 0.70 for the adenomas (adenomas vs hyperplasias, P < 0.01), and 5.22 +/- 0.62 for the adenocarcinomas (adenocarcinomas vs adenomas, P < 0.01). Ki-ras gene mutations were identified in three of four (75%) adenocarcinomas, six of 23 (26%) adenomas, and two of 17 (12%) hyperplasias. No mutations were found in normal lung tissue. The most frequent Ki-ras mutation was an arginine (CGA)AT --> GC transition at codon 61 in exon 2. The PCNA-positive rates and AgNOR scores of cases with Ki-ras mutations were higher than those without an identified mutation (P < 0.05). Ki-ras mutations at codon 61 (Arg) may therefore influence the growth or development of 1-NP-induced lung lesions in A/J mice.
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Yin P, Bai F, Zhou P. [Studies on the yeasts and yeast-like fungi degrading trinitrotoluene]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1998; 38:295-9. [PMID: 12549418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Seventeen strains of yeasts and yeast-like fungi were isolated from soil and waste water samples polluted by trinitrotoluene (TNT). These strains can degrade 71%-93% TNT when growing in the medium originally containing 70-80 mg/L TNT within 40 h. They were identified. Among them, six strains are Candida krusei, four are C. quercitrusa, one is C. famata, one is Hansenula beijerinckii, one is H. subpelliculosa, and four are Geotrichum candidum. Six strains were selected for further studies on the conditions effecting TNT degradation by them. The optimum pH and temperature are pH 7 and 37-40 degrees C, respectively. TNT Degradation ability of the strains can be promoted by adding 0.01%-0.05% glucose or 0.01%-0.1% yeast extract into the medium. Addition of 0.05% (NH4)2SO4 or NH4Cl to the medium can evidently inhibit the degradation of TNT by the strains.
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Matsumoto T, Ohtani-Fujita N, Sowa Y, Bai F, Nikaido T, Tamaki T, Sakai T. Cell cycle-dependent modulation of promoter activities of RB and WAF1/Cip1 genes. Jpn J Cancer Res 1998; 89:626-33. [PMID: 9703360 PMCID: PMC5921868 DOI: 10.1111/j.1349-7006.1998.tb03264.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
A universal inhibitor of cyclin-dependent kinases, WAF1/Cip1 can dephosphorylate the RB gene product to arrest the cell cycle at the G1 phase. Here we show that the mRNA level and the promoter activities of the RB and WAF1/Cip1 genes exhibit cell cycle-dependent change when cells are released from either serum-starvation or the confluent cell state with serum. RB expression and promoter activity are elevated at middle to late G1. In contrast, the mRNA and promoter activity of the WAF1/Cip1 gene increase at early G1. These results suggest that the RB and WAF1/Cip1 expression and promoter activities depend not only on serum, but also on the cell cycle progression itself. Moreover, we identified the responsive region for serum-released cell cycle progression in the RB promoter and mapped it to the region between -4 and -182 relative to the initiating codon of the RB gene. The region in the WAF1/Cip1 promoter responsible for the serum-released cell cycle progression mapped not to the p53 binding site, but to the 374 base-pair region between -1770 and -1396 from the transcription start site.
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356
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Bai F, Guo Y, Shan L, Chen B, Dou X, Guo C, Mao W, Zhou Y. [A study of genetic patterns of idiopathic epilepsy]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 1998; 15:38-41. [PMID: 9456370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To explore genetic patterns of idiopathic epilepsy (IEP). METHODS Using familial analysis, tests for multifactorial inheritance and segregation analysis, we studied 210 pedigrees with IEP found in a population survey in Shangdong province. RESULTS The genetic pattern of IEP is not polygenic but is mainly influenced by autosomal recessive disorders. The results of segregation analysis indicate that the genetic pattern of U*U multiplex families and U*A group is autosomal recessive. Only a few cases in U*U group may accept the assumption of autosomal recessive inheritance while the other are sporadic cases. The frequency of sporadic cases is approximately 78.5%. Genetic heterogeneity may influence U*U(f) group and U*U group. CONCLUSION Further and careful empirical scrutiny of U*U(f) group and the sporadic cases in U*U group offers the best hope for getting a clear understanding of genetic patterns and mechanisms in IEP.
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357
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Xu W, Bai F, Tummalapalli CM, Miller DD, Middaugh L, Boggan WO. The interactive effects of cocaine/gender on immune function in mice. An observation of in vivo acute cocaine exposure. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1997; 19:333-40. [PMID: 9467752 DOI: 10.1016/s0192-0561(97)00025-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The present experiments used a mouse model including both sexes to study the impact of acute cocaine exposure on the function of four major immunocompetent cell types (T, B cells, NK, and macrophages). Cocaine hydrochloride, 5 mg or 40 mg/kg, was administrated by i.p. injection to C57BL/6 mice. Thymocytes and splenocytes were obtained 24 h after injection. Acute in vivo cocaine exposure inhibited the proliferation of T lymphocytes in response to Con-A in both thymocytes and splenocytes. However, the attenuated IL-2 production was only seen in thymocytes. These effects on T cells were greater in male mice than in female mice. The function of macrophages was also impaired by acute cocaine exposure; however, the impact was greater in female than in male mice. In conclusion, the effects of acute cocaine exposure altered the functions of immunocompetent cells and the effects varied with gender.
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358
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Yang J, Bai F, Xu G. [Study on the TICT property of phenothiazine and its derivatives]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 1997; 17:11-14. [PMID: 15810380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The radiationless quantum yields ( phi(nr) ) of phenothiazine (PTH). N-phenyl phenothiazine (PHZ). N-(2-pyridine) phenothiazine (PYZ) and model compound p-N, N-dimethylaminobenzonitrile (DMABN)in benzene were measured. The effects of solvents on phi(nr) of DMABN,PHZ,PYZ and PTH were investigated respectively. It was found that phi(nr) of PYZ and DMABN were dependent on the solvent polar parameter (E(T)(30)) . From the results of radiationless quantum yields and combining the state and dynamic fluorescence spectra, it is proved that PYZ as well as DMABN appears TICT property.
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Pei XH, Nakanishi Y, Takayama K, Bai F, Kawasaki M, Tsuruta N, Mizuno K, Hara N. Effect of CPT-11 in combination with other anticancer agents in lung cancer cells. Anticancer Drugs 1997; 8:231-7. [PMID: 9095327 DOI: 10.1097/00001813-199703000-00003] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To determine the optimal combination of commonly used anticancer agents with 7-ethyl-10-hydroxy-camptothecin (SN-38), an active metabolite of 7-ethyl-10-[4(1-piperidino)-1-piperidino] carbonyloxy camptothecin (CPT-11), for chemotherapy of lung cancer, we studied the effects of SN-38 in combination with six representative anticancer agents on the human small cell lung cancer (SCLC) cell line, NCl N417, and the non-small cell lung cancer (NSCLC) cell line, PC-9. The anticancer activity was evaluated by MTT assay and the effects of drug combinations on ID50 were analyzed by an improved isobologram method. In the SCLC cell line, supra-additive effect was observed for SN-38 in combination with cisplatin, etoposide (VP-16) and paclitaxel (Taxol). An additive effect was observed for its combination with bleomycin. Sub-additive and protective effects were found in combination with adriamycin (ADR) and 5-fluorouracil (5-FU). In the NSCLC cell line, supra-additive and marginal supra-additive effects were found for SN-38 in combination with VP-16, ADR, 5-FU and bleomycin. The others showed additive effects with SN-38. No drug showed sub-additive and protective effects with SN-38. These results suggest that all the drugs we selected can be used with SN-38 simultaneously for NSCLC, while for SCLC, cisplatin, VP-16 and Taxol are the most suitable for combination with SN-38.
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Cesarman E, Nador RG, Bai F, Bohenzky RA, Russo JJ, Moore PS, Chang Y, Knowles DM. Kaposi's sarcoma-associated herpesvirus contains G protein-coupled receptor and cyclin D homologs which are expressed in Kaposi's sarcoma and malignant lymphoma. J Virol 1996; 70:8218-23. [PMID: 8892957 PMCID: PMC190906 DOI: 10.1128/jvi.70.11.8218-8223.1996] [Citation(s) in RCA: 333] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A new human herpesvirus was recently identified in all forms of Kaposi's sarcoma (Kaposi's sarcoma-associated herpesvirus [KSHV] or human herpesvirus 8), as well as in primary effusion (body cavity-based) lymphomas (PELs). A 12.3-kb-long KSHV clone was obtained from a PEL genomic library. Sequencing of this clone revealed extensive homology and colinearity with the right end of the herpesvirus saimiri (HVS) genome and more limited homology to the left end of the Epstein-Barr virus genome. Four open reading frames (ORFs) were sequenced and characterized; these are homologous to the following viral and/or cellular genes: (i) Epstein-Barr virus membrane antigen p140 and HVS p160, (ii) HVS and cellular type D cyclins, (iii) HVS and cellular G protein-coupled receptors, and (iv) HVS. Since there is considerable evidence that cyclin D1 and some G protein-coupled receptors contribute to the development of specific cancers, the presence of KSHV homologs of these genes provides support for a role for KSHV in malignant transformation. All ORFs identified are transcribed in PELs and Kaposi's sarcoma tissues, further suggesting an active role for KSHV in these diseases.
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361
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Pei XH, Nakanishi Y, Takayama K, Yatsunami J, Bai F, Kawasaki M, Wakamatsu K, Tsuruta N, Mizuno K, Hara N. Granulocyte-colony stimulating factor promotes invasion by human lung cancer cell lines in vitro. Clin Exp Metastasis 1996; 14:351-7. [PMID: 8878409 DOI: 10.1007/bf00123394] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of exogenous and endogenous granulocyte colony-stimulating factor (G-CSF) on invasion by cancer cells were studied, using lung cancer cell lines that produce G-CSF (NCI-H157) and lines that do not (PC-9 and NCI-H23). The invasive capacity of NCI-H157 cells was 26- to 27-fold higher than that of PC-9 and NCI-H23 cells. The invasiveness of PC-9 cells was stimulated by exogenous G-CSF, while that of NCI-H157 cells was not. Antibodies against G-CSF blocked the stimulation of PC-9 cell invasiveness by exogenous G-CSF. Anti G-CSF antibodies also inhibited invasion by NCI-H157 cells in the absence of exogenous G-CSF. These results suggest that endogenous and exogenous G-CSF both stimulate invasion by lung cancer cells.
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362
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Bai F, Nakanishi Y, Kawasaki M, Takayama K, Yatsunami J, Pei XH, Tsuruta N, Wakamatsu K, Hara N. Immunohistochemical expression of glutathione S-transferase-Pi can predict chemotherapy response in patients with nonsmall cell lung carcinoma. Cancer 1996; 78:416-21. [PMID: 8697385 DOI: 10.1002/(sici)1097-0142(19960801)78:3<416::aid-cncr6>3.0.co;2-h] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Resistance to chemotherapy agents is a major problem in the treatment of patients with nonsmall cell lung carcinoma (NSCLC). Recent studies have indicated that glutathione S-transferase-Pi (GST-Pi) may play an important role in the resistance of cancer cells to alkylating agents, including cisplatin compounds. METHODS The expression of GST-Pi in tissues obtained by bronchoscopic biopsy from 38 NSCLC patients was investigated immunohistochemically. These patients were treated with a combination of cisplatin-based chemotherapy and were evaluated to determine the relationship between GST-Pi expression and chemotherapy response. RESULTS Of the 38 patients, 25 (66%) were GST-Pi-positive and 13 (34%) were negative. There was no significant correlation between GST-Pi expression and the clinicopathologic factors examined (age, sex, performance status, histology, differentiation grade, and stage). Of the 38 patients treated with cisplatin-based chemotherapy, 12 patients responded to chemotherapy (overall response rate, 32%). For the patients with negative GST-Pi expression, the response rate was 69% (9 of 13 patients). In the patients with positive GST-Pi expression, the response rate was 12% (3 of 25 patients). This difference was statistically significant (P=0.0012). CONCLUSIONS The expression of GST-Pi in NSCLC patients was significantly related to response to cisplatin-based chemotherapy, and may be a useful predictor of chemotherapy response.
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Sasaoka T, Langlois WJ, Bai F, Rose DW, Leitner JW, Decker SJ, Saltiel A, Gill GN, Kobayashi M, Draznin B, Olefsky JM. Involvement of ErbB2 in the signaling pathway leading to cell cycle progression from a truncated epidermal growth factor receptor lacking the C-terminal autophosphorylation sites. J Biol Chem 1996; 271:8338-44. [PMID: 8626530 DOI: 10.1074/jbc.271.14.8338] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To investigate the mechanisms underlying the enhanced mitogenic activity of the truncated epidermal growth factor receptor (EGFR) lacking the C-terminal autophosphorylation sites (Delta973-EGFR), we studied the intracellular signaling pathways in NR6 cells expressing human wild type EGFR and Delta973-EGFR. Microinjection of dominant/negative p21ras(N17) completely inhibited EGF-induced DNA synthesis in both cell types. EGF stimulated Shc phosphorylation as well as the formation of wild type EGFR.Shc complexes. In contrast, EGF stimulated Shc phosphorylation without formation of Delta973-EGFR.Shc complexes. Tyrosine-phosphorylated Shc formed complexes with Grb2.Sos, and microinjection of anti-Shc antibody and Shc-SH2 GST fusion protein inhibited EGF stimulation of DNA synthesis in both cell lines. EGF markedly increased ErbB2 tyrosine phosphorylation in wild type EGFR cells. In Delta973-EGFR cells, ErbB2 was tyrosine phosphorylated in the basal state and EGFR stimulated further phosphorylation of ErbB2. In addition to ErbB2, additional proteins were tyrosine phosphorylated in Delta973-EGFR cells, mostly in the molecular mass range of 120 170 kDa. Taken together with our findings indicating coupling of ErbB2 to Shc, these data suggest the importance of an alternative signaling pathway in Delta973-EGFR cells mediated by the formation of heterodimeric structures between the truncated EGFR and ErbB2, followed by coupling through Shc to Grb2.Sos and the p21ras pathway, ultimately leading to mitogenesis.
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Bai F. Dr. Gu Baochang speaks out on son preference in China. CHINA POPULATION TODAY 1995; 12:27-8. [PMID: 12290273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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365
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Hou Y, Bai F, Wang S. Effect of Melt Convection on the Growth of Nd: YAG Crystal by the Czochralski Method. CRYSTAL RESEARCH AND TECHNOLOGY 1993. [DOI: 10.1002/crat.2170280307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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366
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Zhang Y, Zhang S, Hu X, Liu Q, Bai F, Zhang M. [Study on the variation of relaxation time in diabetic cataractous lenses of rats by using NMRA]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1990; 21:128-30. [PMID: 2167872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Nuclear magnetic resonance analysis (NMRA) was used to measure the relaxation time T1 and T2 of the protons in the different-stage-diseased lenses of rats with diabetic cataract caused by the streptozotocin, and the results were put in comparison with those obtained from the control group, showing that after one month of medication the values of T1 and T2 in the cataractous lenses are greater than those gained from the control group. The variation, as time goes on, becomes greater and greater. T1 and T2 indicate the speed of the free induction decay (FID) signals, and the variation of the FID signals are in direct proportion to that of the proton content of the samples. This shows that an increase in T1 and T2 indicates an increase in the water content in the diseased lenses, and the changes in ratio of "bound" water to free water. Such changes may be explained that the space for "bound" water is occupied by some other macromolecules, causing the alteration of the macromolecular structure, and consequently the aggregation of protein and the degeneration or dehydration or dehydration of the membrane occur, which may give rise to another scattering centre. So the scattering of the lens increases and its transparency decreases. This result is in agreement with some reports in the medical literature. As T1 and T2 are quite different in the normal and pathological tissues, and the protons are the most extensive nucleus in all biological tissues, NMR is a very important method to determine the proton relaxation time in the biological tissue and to judge if it is normal or not.(ABSTRACT TRUNCATED AT 250 WORDS)
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Bai F, Michel R, Rossignol P. Effects of procaine on the oxidative phosphorylation of brain mitochondria from senescent rats. Mech Ageing Dev 1984; 26:277-82. [PMID: 6482524 DOI: 10.1016/0047-6374(84)90100-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Senescence affects cerebral metabolic functions. Various drugs have been tested to counteract the effects of aging on the brain. In this paper, we studied the influence of treatment using procaine, 1 mg per 100 g body weight, injected over a period of 3 days, to both young and old rats, on the phosphorylative oxidation properties of cerebral mitochondria. Respiratory activity decreased significantly in the brain of old rats. This reduction of oxygen consumption measured in the presence of glutamate, reached 31% in state 4, 25% in state 3 and, in the presence of succinate, 23% in state 4 without significant changes in state 3. The injection of procaine into young rats induced a significant increase of oxygen consumption rate with both glutamate and succinate as substrates. The same treatment administered to old rats was followed by a rise in respiratory activity, with values close to those observed in young control rats. Although the mechanism of action of procaine is not yet clear, there is some evidence that it interacts with membrane phospholipid sites. Therefore, it may be concluded that procaine facilitates oxygen transport towards the mitochondrial matrix by modifying the membrane structure in both old and young rats, although, in the latter case, this increase is not intended to improve the energetic properties of the mitochondrion.
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