476
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Qiu H, Ma S, Liu D. [Clinical study of imposed work of breathing caused by the breathing apparatus]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1996; 19:265-8. [PMID: 9596836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The imposed work of breathing caused by the breathing apparatus (endotracheal tube, breathing circuit tubing, and ventilator's valves) may increase patient's work of breathing. To evaluate the imposed work may be useful to determine weaning. METHODS Work of breathing was observed by Bicore CP-100 breathing monitor at different levels pressure support (PS), T piece and after extubation, and the PS level to compensate imposed work of breathing was computed. RESULTS When PS level decreased, patient's work of breathing increased significantly. At PS O kPa, the patient's work of breathing increased 57%, which was caused by imposed work of apparatus. Because of the resistance of endotracheal tube, the patient's work of breathing increased 41% at T piece. The PS level that compensated for the imposed work was 0.7 kPa. CONCLUSIONS When PS level was too low or T piece was applied, the imposed work of breathing caused by apparatus could markedly increase patient's work of breathing.
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Thunecke F, Kálmán A, Kálmán F, Ma S, Rathore AS, Horváth C. Kinetic study on the cis-trans isomerization of peptidyl-proline dipeptides. J Chromatogr A 1996; 744:259-72. [PMID: 8843674 DOI: 10.1016/0021-9673(96)00241-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The equilibrium and kinetic parameters of cis-trans interconversion of dipeptides containing peptidyl-proline moiety were investigated using the in-column incubation method with both CZE and HPLC and the ad hoc dissolution method. The use of the latter was possible because the conformational make-up of the solid peptides, and consequently of their ad hoc solution, was sufficiently different from that of the solution at equilibrium. This method with 1H-NMR and CZE analyses yielded very similar results for the cis-trans isomerization of Phe Pro in aqueous sodium borate, pH 8.4, at 10 degrees C with an average value of 0.34 and 6.6 x 10(-5) s-1 for the equilibrium and rate constant, respectively. The in-column incubation method is performed by CZE or HPLC so that the conformers are separated in the first half of the column and then incubated in column where they interconvert and reach equilibrium. Subsequent separation in the second half of the column yielded four peaks. Thus by measuring the conformer composition as a function of the reaction time, the rate constant can be evaluated. The forward rate constant of 1.42 x 10(-4) s-1 determined by the CZE in-column incubation method for Phe-Pro isomerization at 10 degrees C was twice of the value obtained by the ad hoc dissolution method. It is believed that the inner wall of fused-silica capillaries has a catalytic effect on the isomerization. Computer simulation was also employed to gain further insight on the catalytic activity of the capillary inner wall on such isomerization. Whereas the experimental and simulation profiles of Phe-Pro in aqueous borate buffer, pH 8.4, with a 37 cm long capillary were in excellent agreement, a four times faster interconversion rate had to be used to match the experimental profile obtained with a 57 cm long capillary under otherwise identical conditions. The catalytic effect of the octadecyl silica stationary phase on the isomerization was confirmed by the in-column incubation method with HPLC. The overall rate of the cis-trans isomerization of Phe-Pro, which entails the reaction both on the stationary phase and in the mobility phase, was about six times faster at 0 degree C than the rate measured by NMR in free solution using the mobile phase containing 65% (v/v) sodium phosphate, pH 6.5, and 35% (v/v) methanol. The results presented here serve as a caveat that the effect of the wall in CZE or the stationary phase in HPLC on the reaction cannot be ignored.
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478
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Li J, Xu H, Zhao L, Ma S, Jiang F. [Pharmacognostical study on the Chinese drug biejia]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1996; 21:518-22, 574. [PMID: 9772636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The Chinese drug Biejia is taken from a variety of animals. In this paper, 3 kinds of Biejia from different genera have been studied in their pharmacognostical characteristics and microproperties. A key has been complied based on the experimental results.
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479
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Kubo M, Ma S, Wu J, Matsuda H. Anti-inflammatory activities of 70% methanolic extract from Cinnamomi Cortex. Biol Pharm Bull 1996; 19:1041-5. [PMID: 8874812 DOI: 10.1248/bpb.19.1041] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of 70% methanolic extract (CC-ext) from Cinnamomi Cortex on acute and chronic inflammation were investigated. CC-ext inhibited the rise in vascular permeability induced by acetic acid and the increase of paw edema induced by carrageenin in mice. It was ineffective on edema derived by histamine or bradykinin, and exhibited only weak inhibitory effect on the edema derived by serotonin. CC-ext also showed inhibitory effects on the prekallikrein enzyme activity and ear edema induced by arachidonic acid. It also had an inhibitory effect on cotton pellet-induced granuloma but showed no atrophying action against the adrenal or thymus glands. Little effect was shown on secondary lesions in the development of adjuvant-induced arthritis (the arthritis reappeared from 11 to 27 d after injection of the adjuvant). These results suggest that some active component having an inhibitory effect on acute inflammation is contained in Cinnamomi Cortex.
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480
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Xiang Y, Chang X, Sun N, Xu Y, Ma S. Antenatal diagnosis and management of Dandy-Walker syndrome. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1996; 11:103-5. [PMID: 9387419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The Dandy-Walker syndrome (DWS) can be accurately diagnosed in utero by sonographic demonstration of characteristic morphologic changes of the fetus, which includes hydrocephalus, incomplete cerebellar vermis and a posterior fossa cyst. We present a case of Dandy-Walker syndrome diagnosed antenatally. The associated anomalies are reviewed, and the value of antenatal diagnosis is discussed.
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481
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Ma S, Kalousek DK, Yuen BH, Katagiri S, Moon YS. An improved technique for molecular cytogenetic analysis of human preimplantation embryos with fluorescence in situ hybridization. THE JOURNAL OF REPRODUCTIVE MEDICINE 1996; 41:379-83. [PMID: 8799911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To develop a method for the cytogenetic evaluation of preimplantation embryos using nonradioactive centromeric probes for chromosomes 1, 16 and X. STUDY DESIGN The embryos used for this study were either fragmented or polyploid embryos rejected from an in vitro fertilization program. Prior to in situ hybridization, the embryos were treated with 0.5% protease. After application of gradual fixation, conventional hybridization protocol was followed. RESULTS Ten of 11 embryos showed hybridization signals suggesting that the success rate of in situ hybridization of human embryos is improved when a modified method of digesting the zona pellucida and gradual fixation with removal of the cytoplasm are used. CONCLUSION The method described in this study demonstrates that the zona pellucida is the key to successful in situ hybridization of whole human embryos. When the zona pellucida is removed, penetration by a probe becomes possible.
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482
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Ju D, Cao X, Ma S. [Therapeutic effect of vaccinia virus secreting granulocyte-macrophage colony-stimulating factor on pulmonary metastatic melanoma]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1996; 18:165-8. [PMID: 9387245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A recombinant vaccinia virus containing and expressing the gene of murine granulocyte-macrophage colony-stimulating factor (VVGM-CSF) was tested for its antitumor activity. Murine pulmonary metastasis was established by injecting 2 x 10(5) B16F10 melanoma cells into tail vein of C57BL/6 mouse. Three days after B16F10 inoculation, VVGM-CSF or VVTK, a thymidine kinase gene deficient vaccinia virus, was injected intraperitoneally twice weekly for 2 weeks. Two weeks later mice were sacrificed and pulmonary metastasis foci counted. The results showed that VVGM-CSF treatment significantly decreased the number of pulmonary metastasis and prolonged the survival time of tumor-bearing mice (P < 0.01). Cytotoxic and phagocytic activities of peritoneal macrophages were found to be markedly elevated in mice treated with VVGM-CSF. Nitric oxide released from macrophages was also found to be increased. Based on these data, together with our previous results, we may speculate that continuous secretion of GM-CSF and activation of macrophages might partially explain the antitumor effects of VVGM-CSF.
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483
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Ma S, Sun J. [Ovarian metastasis in uterine cervical cancer: analysis of 17 cases]. ZHONGHUA FU CHAN KE ZA ZHI 1996; 31:305-7. [PMID: 9206188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To investigate the incidence of ovarian metastasis in cervical cancer, especially in early FIGO stages. METHODS Seventeen cervical cancer patients with ovarian metastasis treated at Cancer Hospital, Chinese Academy of Medical Sciences from 1958 to 1994 were retrospectively analysed. The diagnoses of all patients were confirmed by operations and pathologic examinations. RESULTS The incidence of ovarian metastasis in cervical cancer was 0.07% in squamous cell carcinoma and 1.81% in adenocarcinoma (P < 0.05). In early stages (stage l-I), the incidence of ovarian metastasis in adenocarcinoma was higher than that in squamous cell carcinoma (2.2% VS 0.08%, P < 0.05). In patients treated by surgery, the rate of ovarian metastasis in adenocarcinoma was also higher than that in squamous cell carcinoma (7.8% VS 1.6%, P < 0.05). 10 of the 17 cases had macroscopic metastasis and 7 had microscopic metastasis. 11 patients (58.8%) were with bilateral ovarian involvement. Uterine corpus invasion and retroperitoneal lymph node involvements were high risk factors for ovarian metastasis in cervical cancer. The prognosis of cervical cancer patients with ovarian metastasis was poor, the 5-year survival rate in this study being only 17.6%. CONCLUSIONS Patients with cervical cancer are threatened with the risk of ovarian metastasis, especially in adenocarcinoma. Conservative treatment of the cervical cancer with reservation of the ovary should be further investigated.
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484
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Ma S. [Epicanthoplasty during double-fold eyelid operation]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1996; 32:194-6. [PMID: 9590860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE In order to achieve an artistic epicanthoplasty and gain an ideal eyelid double-fold parallel to the lid margin. METHODS Various epicanthoplasty procedures were performed on 183 patients. Combining Fox's plastic operation for correcting upper lid type epicanthus and "L" form removal of skin for correcting lower lid type epicanthus, we put forward three kinds of methods available for epicanthoplasty. According to the degree of seriousness of upper lid type epicanthus, the patients who had a strong desire to receive treatment or improve their looks underwent different operative procedures. The skin resection in 38 cases was of shuttle-form and in 120 cases, of cuneiform: low level "Z"-plasty was performed on 25 cases. RESULTS Satisfactory cosmetic results were obtained in 183 cases. CONCLUSION These methods of plastic surgery can achieve artistic epicanthoplasty in double-fold eyelid operation.
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485
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Bürger H, Ma S, Breidung J, Thiel W. Abinitiocalculations and high resolution infrared investigation on XeF4. J Chem Phys 1996. [DOI: 10.1063/1.471266] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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486
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Ma S, Fang RH, Chang WP. Heterogeneity in radiosensitivity of human diploid fibroblasts from keloids and normal skins. Cell Biol Int 1996; 20:289-92. [PMID: 8664852 DOI: 10.1006/cbir.1996.0032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Colony-forming ability was employed in evaluating the susceptibility to in vitro gamma ionizing radiation in human diploid skin fibroblasts (HDF). Twelve pairs of HDF, each composed of fibroblasts from excised keloid lesion and local normal skin tissue as its control, were studied in patients with clinically persistent keloids. Parameters of radiosensitivity, both D0 and D10, and growth kinetics were examined. The radiosensitivity in three of the 12 keloids (25%) were demonstrated significantly increased than their counterpart controls, even though no difference in growth kinetics in between. Moreover, a broad range in the radiosensitivity of fibroblast cells was demonstrated and it is suggested that there is a great heterogeneity of cellular response to radiation in HDF.
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487
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Cai R, Cao X, Ma S. [Acceleration of hematopoietic reconstitution in mice transplanted with syngeneic bone marrow cells by IL-6 gene therapy]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1996; 18:97-101. [PMID: 9206038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In the present study, the potential of fibroblast-mediated IL-6 gene therapy for accelerating hematopoietic reconstitution after syngeneic bone marrow transplantation (BMT) in BALB/c mice subjected to total body irradiation at a dose of 7 Gy was investigated. We observed that not only recovery of platelets, WBCs, CFU-GM or CFU-MK in bone marrow in mice treated with IL-6 gene therapy in combination with transplantation of 10(7) syngeneic bone marrow cells was faster than that in mice treated with IL-6 gene therapy in combination with transplantation of 10(6) or 10(5) syngeneic bone marrow cells, but also the number of CFU-S or survival rate in mice treated with IL-6 gene therapy in combination with transplantation of 10(7) syngeneic bone marrow cells was significantly higher. Nevertheless, the number of platelets, WBCs, CFU-GM or CFU-MK in bone marrow, CFU-S and survival rate in mice treated with IL-6 gene therapy in combination with transplantation of syngeneic bone marrow cells were elevated more significantly than that in mice transplanted with syngeneic bone marrow cells alone. These data demonstrated that IL-6 gene therapy could markedly augment hematopoietic reconstitution after syngeneic bone marrow transplantation and the more bone marrow cells transplanted, the better was the effect.
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488
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Yang SS, Wong P, Ma S, Cooks RG. SiCl 3 (+) and SiCl (+) affinities for pyridines determined by using the kinetic method with multiple stage mass spectrometry: Agostic effects in the gas phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 1996; 7:198-204. [PMID: 24203242 DOI: 10.1016/1044-0305(95)00630-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/1995] [Revised: 09/07/1995] [Accepted: 09/07/1995] [Indexed: 06/02/2023]
Abstract
Cluster ions, Py1SiCl 3 (+) Py2 and Py1SiCl(+)Py2, where Py1 and Py2 represent substituted pyridines, formed upon reactive collisions of mass-selected SiCl 3 (+) or SiCl(+) cations with a mixture of pyridines, are shown to have loosely bound structures by multiple stage mass spectrometry experiments in a pentaquadrupole mass spectrometer. The fragment ion abundance ratio, ln([Py1SiCl n (+) ]/[Py2SiCl n (+) ]) (n=1 or 3) is used to estimate the relative SiCl 3 (+) or SiCl(+) affinities of the constituent pyridines by the kinetic method. In the case of clusters comprised of meta- and/or para-substituted pyridines (unhindered pyridines), the SiCl 3 (+) and SiCl(+) affinities are shown to display excellent linear correlations with the proton affinities (PAs). On the assumption that the effective temperatures of the SiCl 3 (+) - and SiCl(+)-bound dimers are 555 K (i. e., the same as those of the corresponding Cl(+)-bound dimers), SiCl 3 (+) and SiCl(+) affinities of the substituted pyridines, relative to pyridine, are estimated to be 3-MePy (2.1 kcal/mol), 4-MePy (3.2 kcal/mol), 3-EtPy (3.7 kcal/mol), 4-EtPy (4.2 kcal/mol), 3,5-diMePy (4.8 kcal/mol), and 3,4-diMePy (5.4 kcal/mol). The SiCl 3 (+) and SiCl(+) cation affinities are related to the proton affinities by the expressions: relative (SiCl 3 (+) ) affinity = 0.95 ΔPA and relative (SiCl(+)) affinity = 0.60 ΔPA. The smaller constant in the relationship between the relative SiCl affinity and the relative proton affinity is the result of weaker bonding.Steric effects between the ortho-substituted alkyl group and the central SiCl 3 (+) cation reduce the SiCl 3 (+) affinities of dimers that contain ortho-substituted pyridines. The magnitude of the steric acceleration of fragmentation is used to measure a set of gas-phase steric parameters (S (k)). The steric effects in the SiCl 3 (+) dimers are similar in magnitude to those in the corresponding Cl(+)-bound dimers but weaker than those produced by the bulky [OCNCO](+) group. An inverted steric effect is observed in those SiCl(+)-bound dimers that incorporate ortho-substituted pyridines and is ascribed to auxiliary Si-H-C bonding, which stabilizes the ortho-substituted pyridine-SiCl(+) bond. This auxiliary bonding appears to correspond to agostic bonding, which is well characterized in solution and occurs in competition with steric effects that weaken the pyridine-SiCl(+) interaction.Ion-molecule reactions of pyridines with halosilicon radical cations SiCl 2 (+) and SiCl 4 (+) as well as alkylated halosilicon cations Si(CH3)2Cl(+) and Si(CH3)Cl 2 (+) also are investigated. In these cases, charge exchange and associated reactions are the main reaction channels, and clustering is not observed.
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489
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Ma S, Thompson J, Hu H, Neville DM. Expression and characterization of a divalent chimeric anti-human CD3 single chain antibody. Scand J Immunol 1996; 43:134-9. [PMID: 8633192 DOI: 10.1046/j.1365-3083.1996.d01-22.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Murine anti-CD3 monoclonal antibodies (MoAbs) are used in clinical practice for immunosuppression. However, there are two major drawbacks to this treatment: the associated cytokine release syndrome and human anti-mouse antibody response. To overcome these side-effects, the authors generated a chimeric anti-human CD3 single chain antibody, scUCHT1. It is an IgM variant of UCHT1, a mouse IgG1 MoAb directed against human CD3. scUCHT1 consists of the light and heavy variable chain binding domains of UCHT1 and a human IgM Fc region (CH2 to CH4). scUCHT1 was produced by COS-7 and SP2/0 transfectants, and mainly assembled in a dimeric form. It retained the binding specificity and affinity of the parental MoAb UCHT1. In contrast to UCHT1, scUCHT1 did not induce T-cell proliferation and cytokine release (TNF-alpha and IFN-gamma) in in vitro assays. These results suggest that the engineered chimeric anti-CD3 single chain antibody (scUCHT1) may be useful in clinical immunosuppressive treatment.
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490
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Ma S, Kálmán F, Kálmán A, Thunecke F, Horváth C. Capillary zone electrophoresis at subzero temperatures. I. Separation of the cis and trans conformers of small peptides. J Chromatogr A 1995; 716:167-82. [PMID: 8574385 DOI: 10.1016/0021-9673(95)00555-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The cis-trans conformers of two dipeptides, Phe-Pro and Leu-Pro, and two opioid heptapeptides containing one or two proline residues were separated by capillary zone electrophoresis (CZE) in borate buffer at low temperatures down to -17 degrees C. At temperatures near ambient, the relaxation time of the cis-trans isomerization is on the time-scale of minutes for the dipeptides and thus commensurate with the migration times in CZE under usual operating conditions. The conformers of both dipeptides could be separated with baseline resolution below 10 degrees C in neat aqueous 100 mM sodium borate (pH 8.4). The conformer peaks on the electropherograms were identified by using authentic samples of the cis and trans forms of Phe-Pro and Leu-Pro that were obtained by reversed-phase HPLC at 0 degree C, validated by NMR spectroscopy and stored in liquid nitrogen. The interplay of the electrophoretic migration and on-column isomerization reaction in CZE of Phe-Pro under various conditions was analyzed in the light of the Damköhler number (Da). The results showed that besides employing low temperature increasing the voltage and/or decreasing the capillary length also reduce the magnitude of Da to bring about the separation of interconverting species. In this work the use of low temperature in this work was preferred due to the experimental simplicity. The separation of cis-trans conformers of two opioid heptapeptides was carried out by CZE at subzero temperatures with aqueous sodium borate containing 23% (v/v) glycerol at pH* 11.3 as measured with a glass electrode. The two conformers of Tyr-Pro-Phe-Asp-Val-Val-Gly-NH2 were baseline separated at -12 degrees C and the four conformers of Tyr-Pro-Phe-Gly-Tyr-Pro-Ser-NH2 due to the presence of two peptidyl-proline bonds in the molecule, were also resolved at -12 degrees C. From the electrophoretic mobilities, the hydrodynamic radii of the cis-trans conformers of the dipeptides Phe-Pro and Leu-Pro were estimated. In both cases, the trans isomers had 1.3 times greater Stokes radii than the cis conformers. This agrees with the observed migration order and molecular modeling results. The hydrodynamic radii of the Phe-Pro conformers were smaller than those of the Leu-Pro isomers despite the lower molecular mass of the latter. The results demonstrate that CZE is suitable for measuring certain molecular properties and suggest that the methods introduced here are applicable to the study of other systems of interconverting conformers.
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491
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Ma S, Lin L, Raghavan R, Cohenour P, Lin PY, Bennett J, Lewis RJ, Enwall EL, Kostrzewa R, Lehr RE. In vivo and in vitro studies on the neurotoxic potential of 6-hydroxydopamine analogs. J Med Chem 1995; 38:4087-97. [PMID: 7562944 DOI: 10.1021/jm00020a024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In an attempt to determine which physical and biological properties could best be correlated with neurotoxic potential, seven analogs of 1-(2,4,5-trihydroxyphenyl)-2-aminoethane (1), better known as 6-hydroxydopamine, were synthesized and compared to 1 in a variety of ways both in vivo and in vitro. The analogs, in combination with the standard 1, include all eight of the 2,4,5-trisubstituted-phenyl derivatives of phenethylamine and alpha-methylphenethylamine in which the substitution is of the trihydroxy or aminodihydroxy form. Low (60 nmol) and high (300 nmol) intracerebroventricular doses of all analogs produced long-term (7 day) reduction of mouse whole brain norepinephrine (NE) and lesser depletions of dopamine (DA), and effects on serotonin were varied. The analog 1-(5-amino-2,4-dihydroxyphenyl)-2-aminopropane (8) was both more complete and more selective than the standard 1 in depleting NE. Using a histofluorometric glyoxylic acid method and Fink-Heimer silver degeneration stain, it was determined that overt neural degeneration was produced by 8. In vitro, the ease of oxidation of the eight analogs was found to be represented by a formal potential range of -130 to -212 mV vs SCE. However, there was no obvious relationship between ease of oxidation and the extent of monoamine depletion from mouse brain. Using kinetic analysis of synaptosomal accumulation of [3H]NE and [3H]DA, it was found that the standard 1 is more potent in its interaction with the DA uptake site (Ki = 12 +/- 0 microM) than the NE uptake site (Ki = 51 +/- 1 microM). A correlation analysis was used to determine that differences in NE and DA depletion by each analog could not be explained by differences in potency for in vitro uptake blockade. However, there was a correlation between the Ki for [3H]NE uptake blockade and the EC50 for synaptosomal release of preloaded [3H]NE for the eight analogs (R2 = 0.96; for log:log plot, R2 = 0.54), indicating that the results for these two in vitro tests both reflect interaction with the same NE neuronal membrane transport site. A similar correlation between Ki and EC50 was shown for all eight analogs using [3H]DA (R2 = 0.92; for log:log plot, R2 = 0.52), indicating interaction with the same DA neuronal membrane transport site. These findings demonstrate that there is no single property that can account for selectivity of action and/or potency of catecholamine neurotoxins related to 6-hydroxydopamine.
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492
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Lai ML, Hsu YI, Ma S, Yu CY. Magnetic resonance spectroscopic findings in patients with subcortical ischemic stroke. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1995; 56:31-35. [PMID: 7553407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
BACKGROUND Biochemical changes inside the brain during acute ictus have been extensively studied by means of magnetic resonance spectroscopy (MRS). Previous reports revealed that cerebral cortical infarction causes reduction of N-acetylaspartate (NAA) and elevation of lactate. This study was designed to evaluate the biochemical changes in subcortical infarction. METHODS Nine normal controls and four patients, including two thalamic infarct, one basal ganglia infarct, and one putamen infarct cases were examined using MRS in addition to magnetic resonance imaging (MRI). Evaluation experiments were performed on a Siemens Wagnetom 63SP machine. A spin echo sequence with TE 270 msec was applied for the measurement. The voxel was located at basal ganglia in the controls and at the lesion site, as well as at the contralateral corresponding region in the patients. RESULTS Three resonance signals were present in the spectrum-NAA, choline-containing compounds (Cho) and creatine-phosphocreatine (Cr). The NAA/Cho and NAA/Cr ratios were reduced significantly on the lesion side compared with the controls. NAA/Cho also decreased on the lesion side compared with the healthy side. CONCLUSIONS There is a remarkable reduction of NAA concentration even in subcortical infarction. Further study is needed for the detection of changes in lactate in patients with subcortical lesion.
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493
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Yu Y, Ma Y, Xia T, Ma S, Zhu M, Wan F, Wang Y. [Action of Rhodobrum roserm Limpr on changes of red cell aggregation and yield-shear stress in dogs with acute experimental coronary occlusion]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1995; 20:429-31, 449. [PMID: 7576145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Following acute occlusion of the left anterior descending coronary artery in dogs, significant increases were observed in the red cell aggregation index, yield-shear stress and red cell electrophoretic time in blood drained from ischemic area. When transfusion was performed with Rhodobrum roseum solution from the right femoral vein, significant rises of the above-said items were observed.
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Abstract
The electrophoretic migration behavior of 12 S. nuclease variants from Staphylococcus aureus with small but well defined structural differences from site directed mutation was investigated in free solution capillary electrophoresis at pH 2.8 to 9.5. The nucleases are basic proteins; the pI and the M(r) of the wild type are 10.3 and 16.811 kd, respectively. With specially selected oligoamino buffers and with an inert, hydrophilic wall coating in 75 microns I.D. quartz capillary tubes, most of the proteins could be separated by CZE without interference by wall adsorption even at pH 9.5 where the selectivity was the highest. At pH 2.8, 4.1 and 7.0, S. nucleases are known to be in the random coil, "swollen" and the tight native state. Assuming that in a given state, i.e., at a certain pH, the molecular radii of the nucleases are the same, their hydrodynamic radii were calculated from their pertinent electrophoretic mobilities. The respective radii of 50.1, 26.8, and 25.0 Angstrum thus obtained agreed very well with the corresponding radii of gyration obtained from X-ray scattering. In fact, from the electrophoretic mobilities at pH 9.5, the existence of a hitherto unknown swollen basic state of the nuclease having a hydrodynamic radius of 30.5 Angstrum was postulated. In addition, a method was described to evaluate the valence of the protein at different pH from their pertinent electrophoretic mobilities. A general advantage of this method is that only the differences between the valences of the mutants and the wild type are needed; and for none of the proteins is required the knowledge of the actual valence. The results of the methods allowed the construction of a pH profile of the protein's valence. For the wild type, this profile was compared to the H+ titration curve and the agreement was excellent. Both methods employed some novel structure-electrophoretic mobility relationships and the predicted protein properties compared remarkably well to the values obtained by exoelectrophoretic methods such as pH titration and X-ray scattering. Surprisingly, certain S. nucleases having the same valence could also be readily separated by CZE in some cases under the same conditions used for the others. Close examination of appropriate X-ray crystallography and/or NMR data indicated subtle differences in the molecular structure of these proteins that could be responsible for slight alteration in their hydrodynamic radii.(ABSTRACT TRUNCATED AT 400 WORDS)
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495
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Ma S, Kalousek DK, Yuen BH, Moon YS. The chromosome pattern of embryos derived from tripronuclear zygotes studied by cytogenetic analysis and fluorescence in situ hybridization. Fertil Steril 1995; 63:1246-50. [PMID: 7750595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To detect the chromosomal complement of embryos, which developed from tripronuclear zygote, using nonradioactive centromeric probes. DESIGN The chromosome pattern of embryos developing from tripronuclear zygote, studied by fluorescence in situ hybridization, was compared with that of embryos studied by standard cytogenetic methods. SETTING These embryos were obtained from superovulated patients undergoing IVF treatment. RESULTS We have attempted to examine the chromosomal complement of 72 embryos derived from tripronuclear zygotes using both traditional cytogenetic analysis and fluorescence in situ hybridization. Of these 72 embryos, 22 were analyzed with fluorescence in situ hybridization and 50 were analyzed with traditional cytogenetic analysis. For fluorescence in situ hybridization analysis, probes specific for the centromeric regions of chromosomes 1, 16, and X were used, with results being obtained from 18 embryos. One embryo was haploid (5.6%), five were triploid (27.8%), and one was hexaploid (5.6%). Eleven (61%) embryos were mosaic. Traditional cytogenetic analysis could be performed on 25 of 50 embryos. Five (20%) were haploid, one (4%) was diploid, seven (28%) were triploid, one (4%) were tetraploid, and two were hexaploid. Nine (36%) were mosaic. CONCLUSION These findings indicate that not all tripronuclear human zygotes develop into triploid embryos. This study also demonstrates the usefulness of fluorescence in situ hybridization for preimplantation diagnosis and screening for chromosome abnormalities.
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496
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Ma S, Feldman AG. Two functionally different synergies during arm reaching movements involving the trunk. J Neurophysiol 1995; 73:2120-2. [PMID: 7623104 DOI: 10.1152/jn.1995.73.5.2120] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. To address the problem of the coordination of a redundant number of degrees of freedom in motor control, we analyzed the influence of voluntary trunk movements on the arm endpoint trajectory during reaching. 2. Subjects made fast noncorrected planar movements of the right arm from a near to a far target located in the ipsilateral work space at a 45 degrees angle to the sagittal midline of the trunk. These reaching movements were combined with a forward or a backward sagittal motion of the trunk. 3. The direction, positional error, curvature, and velocity profile of the endpoint trajectory remained invariant regardless of trunk movements. Trunk motion preceded endpoint motion by approximately 175 ms, continued during endpoint movement to the target, and outlasted it by 200 ms. This sequence of trunk and arm movements was observed regardless of the direction of the endpoint trajectory (to or from the far target) or trunk movements (forward or backward). 4. Our data imply that reaching movements result from two control synergies: one coordinates trunk and arm movements leaving the position of the endpoint unchanged, and the other produces interjoint coordination shifting the arm endpoint to the target. The use of functionally different synergies may underlie a solution of the redundancy problem.
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497
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Ma S, Shieh LI, Huang CC. High-resolution proton nuclear magnetic resonance studies of urine from asphyxiated newborn infants. Appl Biochem Biotechnol 1995; 53:37-51. [PMID: 7625824 DOI: 10.1007/bf02783480] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
High-resolution proton nuclear magnetic resonance spectroscopy was used to study human urine obtained from 10 normal babies and twenty babies with various degrees of neonatal asphyxia, respiratory distress syndrome (RDS), and meconium aspiration syndrome (MAS). All sick babies showed different degrees of oxygen deficiency, indicated by an obvious increase of the lactate signal level in the urine spectra. Changes in the concentration of other urinary metabolites produced from the citric acid cycle were also observed. In extremely serious cases, the signals of some of the major components, including citrate, alpha-ketoglutarate, and succinate, simply disappeared. The spectra of urine, serum, and CSF of an infant suffering from SIDS showed common characteristics of the metabolites.
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498
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Kálmán F, Ma S, Hodel A, Fox RO, Horváth C. Charge and size effects in the capillary zone electrophoresis of nuclease A and its variants. Electrophoresis 1995; 16:595-603. [PMID: 7588531 DOI: 10.1002/elps.1150160196] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The migration behavior of nuclease A from Staphylococcus aureus and 11 of its variants in capillary zone electrophoresis (CZE) was investigated in the light of their three-dimensional structure known from X-ray crystallography and nuclear magnetic resonance (NMR) measurements. Nuclease A (molecular mass 16.8 kDa, pKa 10.3) and the variants differ only in a single amino acid residue and have a very similar crystal structure. With the use of coated quartz capillaries and suitable buffers, the protein migration was investigated at pH from 2.8 to 9.5 without interference by wall adsorption. Although the selectivity of the electrophoretic system for the proteins was mainly determined by their charge differences, certain variants having the same net charge could also be readily separated under nondenaturing conditions. For instance, the mobility of variant K116A was sufficiently higher than that of K116G so that they could be separated by CZE. The structures of both variants are the same except for the solvent-exposed loop containing residue 116. For this reason, the difference in electrophoretic mobilities can be attributed to the fact that in K116G the backbone of the 112 to 117 amino acids protrudes slightly from the protein, with a concomitant increase in the hydrodynamic radius with respect to that of K116A. Consequently, K116G shows a smaller mobility than K116A due to its larger hydrodynamic radius despite its smaller molecular mass. The interpretation of the experimentally measured mobilities of such closely related proteins therefore requires not only consideration of their electrostatic charge but also the fine details of their molecular structures.
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499
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Ma S, Lin D, Sun J. [Adenocarcinoma of the cervix--analysis of 363 cases]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1995; 17:149-51. [PMID: 7656810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Form 1959 through to May, 1993, 363 patients with adenocarcinoma of uterine cervix were initially treated which accounted for 2.5% of all initially treated cases of cervical carcinoma. Patients' mean age was 50.5 years. Forty-six percent of the patients were post-menopausal. The main symptom was irregular vaginal and/or discharge. Over 88% of the cases were in stage II and III of the disease. They were treated with radiotherapy alone. The overall 5-year survival rate was 51.8%. The recurrence rate was 17.4% with a mean time to recurrence of 33.3 months. Thirteen patients recurred beyond 5 years. Recurrence was accompanied with lung metastasis in 17 patients and supraclavicular eymph node metastases in 11. Among patients whose tumor recurred the 1- and 2-year survival rate were 35.2% and 19.2% respectively. The most significant prognostic factors were the stage of disease, the size of the tumor and the histologic subtypes
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500
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Gurram R, Rakheja S, Gouw GJ, Ma S. Influence of power tool-related parameters on the response of finger flexor muscles. Int Arch Occup Environ Health 1995; 66:393-8. [PMID: 7782123 DOI: 10.1007/bf00383146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Surface electromyography (EMG) and statistical analysis techniques were applied to investigate the response of finger flexor muscles to hand-transmitted vibration in all the three orthogonal directions. The trends in measured data were examined to derive the influence of variations in the tool-related parameters. Single-factor and multi-factor statistical analyses were performed to establish the significance of influence of different individual and coupled power tool-related parameters. The analysis of variance (ANOVA) results indicated that the vibration direction, acceleration and grip force influence the EMG of finger flexor muscles in a significant manner (P < 0.001), while the effect of vibration frequency was observed to be insignificant (P > 0.9). The electrical activity measured under different vibratory test conditions was observed to be 1.5-6.0 times higher than that measured under the static loads. The increase in electrical activity of the finger flexor muscles with an increase in the grip force was observed to be most significant under static as well as dynamic loading conditions.
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