451
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Luo L, Luo S, Luo J. [Clinical experience in the treatment of chronic radiation ulcer in 32 cases]. 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 1997; 13:279-81. [PMID: 10452014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
A retrospective study was carried out, aiming at a proper treatment to the chronic radiation ulcer that is often difficult to deal with. Thirty-two cases of chronic radiation ulcer have been treated in the department since 1983. The cause, site, features and method of treatment were summarized. Thirty-one cases were cured, 26 cases healed by the first intention, 5 cases healed by the second intention. One died. It is emphasized that more knowledge should be gained for understanding and treatment of the chronic radiation ulcer. Different methods of debridement and repair should be performed according to the site, depth and pathologic features of the ulcer. To improve local circulation, an island flap is the first choice of treatment.
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452
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Luo L, Wang Q, Chen Y, Yu X. [Temperature measuring and heating controlling in transurethral prostate thermotherapy system]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 1997; 21:204-206. [PMID: 11189255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper introduces the system construction of Transurethral Prostate Thermotherapy Device. The temperature measuring device, I/O interface circuit and the programming principle of PID controlling system is illustrated also.
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453
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Xie F, Luo L, Tian X. [A knowledge-based method for 3D segmentation and display of human brain]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 1997; 14:124-7, 136. [PMID: 9817639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
From the view of the artificial intelligence, a new method of segmentation and display of human brain medical images is descrided. On the basis of the knowledge of brain anatomy and image processing, we have built the 3D knowledge mobel using frame as the main knowledge expression method. Under the guide of the knowledge, the main structures in the brain are segmented and displayed by means of the "inelligent ray-tracing".
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454
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Luo L, Cruz T, McCulloch C. Interleukin 1-induced calcium signalling in chondrocytes requires focal adhesions. Biochem J 1997; 324 ( Pt 2):653-8. [PMID: 9182730 PMCID: PMC1218478 DOI: 10.1042/bj3240653] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The cytokine interleukin 1 (IL-1) is an important mediator of connective-tissue destruction in arthritic joints but the mechanisms by which IL-1 mediates signal transduction in chondrocytes is poorly understood. Previous results have indicated that IL-1 receptors co-localize with focal adhesions [Qwarnstrom, Page, Gillis and Dower (1988) J. Biol. Chem. 263, 8261-8269], discrete adhesive domains of cells that function in cell attachment and possibly in signal transduction. We have determined whether focal adhesions restrict IL-1-induced Ca2+ signalling in primary cultures of bovine chondrocytes. In cells grown for 24 h on fibronectin, the basal intracellular Ca2+ ion concentration ([Ca2+]i) was 100+/-3 nM. Optimal increases of [Ca2+]i above baseline were induced by 10 nM IL-1 (183+/-30 nM above baseline). There was no significant difference between cells plated on fibronectin or type II collagen (P>0.2; 233+/-90 nM above baseline). Ca2+ transients were significantly decreased by the inclusion of 0.5 mM EGTA in the bathing buffer (74+/-11 nM above baseline), and 1 microM thapsigargin completely blocked Ca2+ transients. Cells plated on poly-(l-lysine) or suspended cells showed no Ca2+ increases, whereas cells grown on fibronectin exhibited IL-1-induced Ca2+ responses that corresponded temporally to the time-dependent cell spreading after plating on fibronectin. Cells plated on poly-(l-lysine) and incubated with fibronectin-coated beads exhibited vinculin staining in association with the beads. In identical cell preparations, IL-1 induced a 136+/-39 nM increase of [Ca2+]i above baseline in response to 10 nM IL-1beta. There were no IL-1-induced Ca2+ increases when cells on poly-(l-lysine) were incubated with fibronectin-coated beads for only 15 min at 37 degrees C, in cells maintained for 3 h at 4 degrees C, in cells incubated with BSA beads for 3 h at 37 degrees C, or in cells pretreated with cytochalasin D. Labelling of IL-1 receptors with 125I-IL-1beta showed 3-fold more specific labelling of focal adhesion complexes in cells incubated with fibronectin-coated beads compared with cells incubated with BSA-coated beads, indicating that IL-1 receptor binding or the number of IL-1 receptors was increased in focal adhesions. These results indicate that, in chondrocytes, IL-1-induced Ca2+ signalling is dependent on focal adhesion formation and that focal adhesions recruit IL-1 receptors by redistribution in the cell membrane.
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455
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Luo L, Dai Z. [Retrospective epidemiological study of pregnancy complicated by heart disease during 15 years in Shanghai]. ZHONGHUA FU CHAN KE ZA ZHI 1997; 32:336-40. [PMID: 9596911] [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 To investigate the changes of pregnancy complicated by heart disease. METHOD Clinical data of hospitalized pregnant women with heart disease, collected from 10 teaching hospitals in Shanghai during 1981-1995, were analysed retrospectively. RESULTS 2,680 of 379,065 deliveries (0.71%) were complicated by heart disease during that period. There were a total of 121 maternal deaths, 15 of them due to heart disease, the mortality of heart disease was 0.56%, and the percentage in total maternal deaths was 12.40%. The incidence and mortality rates were similar in 1981-1985, 1986-1990, 1991-1995, but the percentage due to heart disease increased after the late 1980s. The rates of congenital heart disease increased and rhumatic heart disease decreased apparently, the ratio of the former to the latter was 1.76:1. The pregnancy induced hypertension heart disease, the peripartum cardiomyopathy and the miscellaneous heart disease all increased obviously during the 1990s. The heart functions of grade I and II accounted for a considerable proportion (85.45%), but the grade IV tended to increase during the 1990s. Heart failure occurred in 172 cases, with an incidence of 7.6%. The perinatal mortality rate was 7.76%. Cesarean sections were often performed in heart disease women. CONCLUSION Pregnancy complicated by heart disease is still one of the major cause of maternal deaths up till now. More effective management should be adopted.
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456
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Luo L, Zhang Y, Huang L. [Modulation of invasiveness and invasion/metastasis-associated gene expression of a mouse mammary adenocarcinoma by interferons]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1997; 19:184-7. [PMID: 10920892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
OBJECTIVE To investigate the effects of IFNs on the in vitro invasiveness and the expression of several genes related to invasion and metastatic behavior of MA-891 cells. METHODS The invasiveness was assessed by penetration through a matrigel-coated filter. Cell surface antigen and mRNA levels were analyzed by flow cytometry and Northern blot respectively. RESULTS IFN-gamma pretreatment increased the invasiveness of MA-891 (P < 0.01). Pretreatment with IFN-alpha decreased the invasiveness of cells, but it was not statistically significant. Cell surface ICAM-1 was not found on MA-891 cells even after treatment with IFN-alpha, but was strongly induced after IFN-gamma treatment. Another adhesion molecule CD44v mRNA, absent on MA-891 cells, could not be induced to express by either IFN. Both 72,000 and 92,000 type IV collagenase mRNAs were detectable in MA-891 cells. The 72 kD-type IV collagenase expression was up-regulated by IFN-gamma and IFN-alpha, but the levels of expression were significantly higher in cells treated with IFN-gamma than those treated with IFN-alpha. IFN-gamma and IFN-alpha treatment had little or no effect on expression of the 92,000 type IV collagenase. Treatment with IFN-gamma had no effects on antimetastasis nm23 gene expression whereas treatment with IFN-alpha resulted in marked up-regulation of its expression. CONCLUSION IFN-gamma and IFN-alpha differ in their effects on the expression of genes related to invasion and metastasis of MA-891 cells, thereby differentially modulating metastatic potential.
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457
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Hu YJ, Chen Y, Zhang YQ, Zhou MZ, Song XM, Zhang BZ, Luo L, Xu PM, Zhao YN, Zhao YB, Cheng G. The protective role of selenium on the toxicity of cisplatin-contained chemotherapy regimen in cancer patients. Biol Trace Elem Res 1997; 56:331-41. [PMID: 9197929 DOI: 10.1007/bf02785304] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of selenium (Se) in reducing the toxicity of cisplatin in cancer patients was studied. Forty-one patients were randomized into group A (20 patients with Se administration in first cycle of chemotherapy as study cases and without Se in second cycle of chemotherapy as control) and group B (21 patients without Se in first cycle of chemotherapy and with Se in second cycle of chemotherapy). The 4000 micrograms per day of Se as Seleno-Kappacarrageenan were administered from 4 before to 4 d after chemotherapy for study cases. The serum Se increased from 70.4 +/- 22.86 to 157.04 +/- 60.23 ng/mL (P < 0.001) in patients received Se. The cisplatin dosage was iv administration in 60-80 mg/m2 on the first day. The results showed that the peripheral WBC counts on day 14 after initiation of chemotherapy in study cases was significantly higher than the controls (3.35 +/- 2.01 vs 2.31 +/- 1.38 [x10(9)L])/L, p < 0.05). On the other hand, the consumption of GCSF for the cases was significantly less than the controls (110.1 +/- 82.2 vs 723.6 +/- 192.6 IU, p < 0.05). The volumes of blood transfusion for the study group were also significantly less than the controls (0 vs 62 +/- 38 mL, p < 0.05). The nephrotoxicity of cisplatin was measured by urine enzymes (NAG, GGT, AAP, LAP, and ALP) were determined prior to and at 2, 24, 48, and 72 h after initiation of chemotherapy. The urine enzymes NAG, GGT, AAP, and ALP after chemotherapy for cases were significantly lower than the controls. No toxicity of Seleno-Kappacarrageenan was noted. The above results suggest that the Se can be used as an agent for reducing the nephrotoxicity and bone marrow suppression induced by cisplatin.
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458
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Jiang P, Luo L. [The effect of far infrared rays on the survival of randomized skin flap in the rat: an experimental study]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1997; 11:69-71. [PMID: 9867958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In order to observe the effect of far infrared rays on the survival of skin flap, the following experiment was performed. Forty-eight SD rats were selected and divided into two groups. The rats received 0.3 w/cm2 radiation twice a day from 3 days before operation to 5 days after operation in the experimental group, while in the control group the rats received none before or after the operation. The flap was designed as 2 cm x 6 cm in the back of the rats with the pedicle caudalward. The microcirculatory changes of the flap were observed, and the survival area of the flap was calculated. The results showed that either in the proximal or in the distal part of the graft, in the experimental group, the mean opening rate, diameter and the flowing velocity of the microvessels were significantly higher than those in the control group (P < 0. 05). The mean rate of survival area of the experimental group (80.5%) was also higher than that of the control group (62.7%) (P < 0.01). It was suggested that radiation with far infrared rays could dilate the microvessels, improve the flap microcirculation, therefore, enhance the survival of the randomized skin flap.
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459
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Jiang P, Luo L. [Effects of hyperbaric oxygen on the skin graft survival]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1997; 11:91-3. [PMID: 9867965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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460
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Abstract
Rho family GTP-binding proteins regulate various aspects of the actin cytoskeleton in a wide variety of organisms. Recent evidence suggests that they may also be important components of the signalling pathways that link the reception of extracellular cues to the regulation of the cytoskeleton in neuronal growth cones.
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461
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Luo L, Lü Q, Wei F. [Fetal fibronectin and preterm birth]. ZHONGHUA FU CHAN KE ZA ZHI 1997; 32:25-6. [PMID: 9596866] [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 To determine whether fetal fibronectin is a sensitive test for the diagnosis and prediction of preterm birth. METHODS Fetal fibronectin was measured by enzyme-labeled immunosorbent assay (ELISA) methods in sample of cervical secretion from 38 women with threatened preterm delivery (study group) and 43 normal pregnanty women with same gestational weeks (control group). RESULTS The positive rate of fetal fibronectin in women with threatened preterm birth was significantly higher than that in the normal control group. CONCLUSION Fetal fibronectin is an important marker. It can be used for diagnosis and prediction of preterm birth.
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462
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McEvilly RJ, Erkman L, Luo L, Sawchenko PE, Ryan AF, Rosenfeld MG. Requirement for Brn-3.0 in differentiation and survival of sensory and motor neurons. Nature 1996; 384:574-7. [PMID: 8955272 DOI: 10.1038/384574a0] [Citation(s) in RCA: 197] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Specific families of transcription factors mediate events in the sequential maturation of distinct neuronal phenotypes. Members of one such family, the class IV POU domain transcription factor Brn-3.0, and two highly related factors Brn-3.1 and Brn-3.2, are differentially expressed in the developing and mature mammalian nervous system. The expression pattern of Brn-3.0 suggested that it has an important role in the development of sensory ganglia, as well as red nucleus, inferior olive, and nucleus ambiguus. Analysis of mice null for the Brn-3.0 locus shows that Brn-3.0 is required for the survival of subpopulations of proprioceptive, mechanoreceptive and nociceptive sensory neurons, where deletion of the gene affects neurotrophin and neurotrophin-receptor gene expression. Deletion of Brn-3.0 also alters either differentiation, migration or survival of specific central neuronal populations.
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463
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Luo L, Wu SZ, Zhu C, Fan Q, Liu K, Sun G. Psychological long-term effects of sterilization on anxiety and depression. Contraception 1996; 54:345-57. [PMID: 8968663 DOI: 10.1016/s0010-7824(96)00200-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Two-thousand cases (500 women and 500 men with sterilization; 500 women and 500 men without sterilization) in two counties and two cities in Sichuan, China, were investigated between 15 September 1992 and 30 April 1993. Information was obtained about their age, parity, marriage, contraceptives, social behavior, and present psychological characteristics. CES-D, SAS, and E.P.Q. scales were used to assess the depressive symptomatology, anxiety, and personality of the subjects. The results revealed that sterilization psychologically affected the depressive symptoms and anxiety under the neutral personality. In addition, depressive symptoms and anxiety were related to the subjects' age, educational level, income, operative doctors' attitudes to sterilization acceptors, and subjects' understanding of the sterilization.
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464
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Luo L, Li S, Cai Y. Effect of hypoxia on DNA synthesis and c-myc gene expression of pulmonary artery smooth muscle cells. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1996; 11:224-7. [PMID: 9387387] [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 neonate is particularly susceptible to the development of hypoxic pulmonary hypertension. The present study was undertaken to observe the effect of hypoxia on DNA synthesis and c-myc gene expression between newborn calf and adult bovine PASMC in vitro. DNA synthesis measured by 3H-TdR incorporation was increased after hypoxic challenge for 24h. Hypoxia enhanced the increment in 3H-TdR incorporation induced by EGF. Northern blot analysis revealed that PASMC cultured in both normoxia and hypoxia expressed c-myc gene transcript of 2.2Kb, but there is a higher 2. 2Kb mRNA expression in hypoxic PASMC than that in normoxia. We speculate that newborn calf PASMC exhibited potential response to hypoxia than adult, which was augmented by EGF. Enhanced c-myc gene expression may lead to a great understanding of the mechanism of PASMC growth in the development of pulmonary hypertension.
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465
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Luo L, Yuan W, Tian J, Zhang Y. [Expression of retroviral transmembrane envelope protein p15E in human malignant cells]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1996; 18:416-22. [PMID: 9388946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Malignant tumor growth is always accompanied with immune suppression. Tumor-derived immuno-suppressive factors, among others, are thought to be responsible, but their nature is not well defined. The paper reports on the expression of an immuno-suppressive retroviral transmembrane envelope protein p15E at different levels in human cancer cells. By using immunohistochemistry, enzyme-linked immunosorbent assay, flow cytometry and in situ hybridization, p15E expression could be demonstrated in cancers of the esophagus, nosopharynx, rectum, ovary (including malignant effusion and cell lines), stomach and breast. Enhanced expression of p15E was also observed in activated lymphocytes of cancer patients as shown by RT-PCR technique. The results indicate that p15E of tumor origin, and perhaps that from activated lymphocytes, may contribute to the immune suppression associated with malignancy.
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466
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Kanjhan R, Housley GD, Thorne PR, Christie DL, Palmer DJ, Luo L, Ryan AF. Localization of ATP-gated ion channels in cerebellum using P2x2R subunit-specific antisera. Neuroreport 1996; 7:2665-9. [PMID: 8981443 DOI: 10.1097/00001756-199611040-00051] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The distribution of the P2x2 purinoceptor subunit protein, which forms ATP-gated ion channels by homo- and hetero-multimeric assembly, was examined in the adult rat and guinea-pig cerebellum using two novel antisera generated against separate 18 amino acid sequences located in the predicted extracellular domain of this subunit. These antisera, the first available for labelling the P2x2R subunit protein, were validated by selective labelling of a fusion protein containing the target amino acid sequences, and in cerebellum, by peptide specific block of immunoreactivity and by comparison with the distribution of P2x2R mRNA. P2x2R-like immunoreactivity was seen in Purkinje cells, specifically the soma and dendrites, neurons in the granular and molecular layers and deep cerebellar nuclei. The identification of P2x2R-like immunoreactivity within the cerebellar neural circuitry is consistent with a role for extracellular ATP acting as a fast neurotransmitter in motor learning and coordination of movement. Additionally, labelling of neuroglia and fibre tracts supports a diverse role for extracellular ATP in CNS homeostasis.
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467
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Vorechovský I, Luo L, Lindblom A, Negrini M, Webster AD, Croce CM, Hammarström L. ATM mutations in cancer families. Cancer Res 1996; 56:4130-3. [PMID: 8797579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Ataxia-telangiectasia (A-T) is a multisystem recessive disease characterized clinically by cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency, sensitivity to radiomimetic agents, and cancer predisposition. This pleiotropic disorder is caused by mutations in the ATM (mutated in A-T) gene, which is located in the human chromosomal region 11q22-q23. The ATM gene product is a member of a novel family of large proteins implicated in the regulation of the cell cycle and response to DNA damage. Heterozygosity for A-T was previously suggested to be associated with an increased risk of tumors, particularly female breast cancer. Because of loss of constitutional heterozygosity at 11q22-q23 is a frequent event in breast and other tumors, suggesting the presence of a tumor suppressor gene(s) in this region, we screened blood DNA samples from 88 unrelated breast cancer patients of Swedish cancer families for ATM mutations using single-strand conformation polymorphism analysis. All patients had a family history of tumors previously associated with A-T heterozygosity or homozygosity. We demonstrate the first three germ-line mutations in ATM identified by screening of breast cancer patients. Two mutations were previously found in A-T homozygotes and one mutation was a 1-bp insertion. All mutations were found in families with a large number of tumors, however, they did not cosegregate with malignancies. Although the proportion of A-T carriers in this sample seems to be higher than expected by chance, larger studies and pooled data sets will be required to establish that an A-T allele confers cancer susceptibility in heterozygotes.
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468
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Li Y, Bergeron JJ, Luo L, Ou WJ, Thomas DY, Kang CY. Effects of inefficient cleavage of the signal sequence of HIV-1 gp 120 on its association with calnexin, folding, and intracellular transport. Proc Natl Acad Sci U S A 1996; 93:9606-11. [PMID: 8790377 PMCID: PMC38475 DOI: 10.1073/pnas.93.18.9606] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The HIV-1 envelope glycoprotein gp120 displays inefficient intracellular transport, which is caused by its retention in the endoplasmic reticulum. Coexpression in insect cells (Sf9) of HIV-1 gp120 with calnexin has shown that their interaction was modulated by the signal sequence of HIV-1 gp120. gp120, with its natural signal sequence, showed a prolonged association with calnexin with a t1/2 of greater than 20 min. Replacement of the natural signal sequence with the signal sequence from mellitin led to a decreased time of association of gp120 with calnexin (t1/2 < 10 min). These different times of calnexin association coincided both with the folding of gp120 as measured by the ability of bind CD4 and with endoplasmic reticulum to Golgi transport as analyzed by the acquisition of partial endoglycosidase H resistance. Using a monospecific antibody to the HIV-1 gp120 natural signal peptide, we showed that calnexin associated with N-glycosylated but uncleaved gp120. Only after dissociation from calnexin was gp120 cleaved, but very inefficiently. Only the small proportion of signal-cleaved gp120 molecules acquired transport competence and were secreted. This is the first report demonstrating the effect of the signal sequence on calnexin association.
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469
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Cai Y, Han M, Luo L, Song W, Zhou X. Increased expression of PDGF and c-myc genes in lungs and pulmonary arteries of pulmonary hypertensive rats induced by hypoxia. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1996; 11:152-156. [PMID: 9387399] [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 role of growth factors and proto-oncogene in pulmonary vascular structural remodelling is not well known. The present study examined gene expression of platelet-derived growth factor (PDGF)-A and -B chain and proto-oncogene, c-myc, in lung tissue and pulmonary artery of rats exposed to hypoxia and compared to those levels of gene expression in normal rats. Normal lungs and pulmonary artery expressed PDGF-A chain transcript of 1.7 kb and PDGF-B chain transcript of 3.5 Kb. The c-myc transcript of 2.2 kb was expressed as well. After hypoxic exposure for 7 and 14 days mRNA levels of PDGF-B chain and c-myc were elevated significantly compared with those of control rats. PDGF-A chain mRNA increased after hypoxia for 7 days, and then declined. These results suggest that activation of autocrine and/or paracrine is important in proliferation mechanism of pulmonary artery smooth muscle cells in hypoxic pulmonary hypertensive rats.
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470
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Luo L, Chen H, Zirkin BR. Are Leydig cell steroidogenic enzymes differentially regulated with aging? JOURNAL OF ANDROLOGY 1996; 17:509-15. [PMID: 8957694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Previous studies have shown that the ability of Brown Norway rat Leydig cells to produce testosterone declines significantly with age. To address the possible mechanism(s) by which aging Leydig cells lose steroidogenic function, we determined the effect of age on the steady-state levels of the mRNAs for the steroidogenic enzymes P450 cholesterol side-chain cleavage (P450scc), delta 5-3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase (3 beta-HSD), and 17 alpha-hydroxylase/C17-20 lyase (P450(17) alpha), and on the levels of immunoreactive steroidogenic enzyme proteins and enzyme activities. Northern blot analysis revealed that the levels of P450scc and P450(17) alpha mRNAs in Leydig cells isolated from the testes of aged (22-month-old) Brown Norway rats were reduced from their levels in young (4-month-old) rats, but that 3 beta-HSD mRNA was not reduced. Western blot analysis, however, revealed that cellular levels of each of the P450scc, P450(17) alpha, and 3 beta-HSD proteins were reduced with aging. The activities of the steroidogenic enzymes, assessed by incubating Leydig cells in culture with substrate and then summing all steroidogenic reaction products through testosterone, similarly revealed that P450scc, 3 beta-HSD, P450(17) alpha, and additionally 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD), were all reduced with aging. We conclude that age-related loss of steroidogenic function results at least in part from reductions in the levels and activities of each of the steroidogenic enzymes responsible for converting cholesterol to testosterone, and not by differential regulation of these enzymes.
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471
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Torroja L, Luo L, White K. APPL, the Drosophila member of the APP-family, exhibits differential trafficking and processing in CNS neurons. J Neurosci 1996; 16:4638-50. [PMID: 8764652 PMCID: PMC6579020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The Drosophila Appl gene encodes a transmembrane protein that is expressed exclusively in neurons. Amino acid comparisons show that APPL protein is a member of the amyloid precursor protein (APP)-like family of proteins. Similar to mammalian APP-family proteins, APPL is synthesized as a transmembrane holoprotein and cleaved to release a large secreted amino-terminal domain. Using immunocytochemical methods, we have analyzed the distribution of APPL in the Drosophila CNS. Surprisingly, although APPL is present in all neuronal cell bodies, the neurophil shows sterotypic differential distribution. Double-labeling experiments with different neuronal markers were used to distinguish between APPL associated with neuronal processes or extracellular matrix. The distribution of APPL protein produced from transgenes encoding wild-type (APPL), secretion-defective (APPLsd), and constitutively secreted (APPLs) forms was analyzed in an Appl-deficient background to determine which APPL form is associated with different neuropil regions. We found that APPLsd protein is enriched where APPL immunoreactivity coincides with neuronal processes. In contrast, APPLs preferentially localizes to those parts of the neuropil that show a diffuse APPL signal that rarely colocalizes with processes, and thus seems to be a component of the extracellular matrix. These data indicate that proteolytic cleavage and trafficking of APPL is differentially regulated in different neuronal populations. Through metamorphosis, APPL is especially abundant in growing axons and in areas where synapses are forming. Interestingly, in adult brains, APPL protein is enriched in the mushroom bodies and to a lesser extent in the central complex, structures involved in learning and memory.
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472
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Li H, Luo L. The relation between codon usage, base correlation and gene expression level in Escherichia coli and yeast. J Theor Biol 1996; 181:111-24. [PMID: 8935590 DOI: 10.1006/jtbi.1996.0119] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Based on the investigation of the relation between gene expression and the usage of synonymous codons, a method of classifying and predicting the gene expression level is proposed which is called the Self-consistent Information Clustering (SCIC). Using the modified Codon Adaption Index (CAI) values, we have accomplished the linear regression analysis on the relation between base composition, base correlation and gene expression level in Escherichia coli and yeast. The assumption of Expression-Enhancing-Network Site (EENS) is proposed, the existence of which can be demonstrated by the linear equations between gene expression and base correlations in a codon, in adjacent codons and in non-adjacent codons. The modes of base correlation of E. coli and yeast which are important to gene expression have been found and listed in this paper.
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473
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Vorechovský I, Rasio D, Luo L, Monaco C, Hammarström L, Webster AD, Zaloudik J, Barbanti-Brodani G, James M, Russo G. The ATM gene and susceptibility to breast cancer: analysis of 38 breast tumors reveals no evidence for mutation. Cancer Res 1996; 56:2726-32. [PMID: 8665503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Heterozygosity for ataxia-telangiectasia (A-T), a cancer-prone recessive syndrome, has been associated with an increased risk of breast cancer. The gene for A-T (ATM) is located at chromosomal region 11q22-q23, a region of frequent loss of constitutional heterozygosity in breast and other tumors. Loss of constitutional heterozygosity at 1lq22-q23 was found in 47% of informative cases in the series of primary tumors analyzed in this study. To investigate the role of ATM in breast cancer, we have determined the complete genomic organization of the gene, developed an exon-scanning PCR single-strand conformation polymorphism (PCR-SSCP) assay for mutation detection of ATM, and screened 38 consecutive breast tumors for mutations using both genomic DNA- and cDNA-based assays. In addition to common ATM polymorphisms detected both in the coding sequence and in flanking introns, seven unique SSCP alleles were identified in six tumor DNAs. Sequence analysis of these alleles revealed rive nucleotide substitutions that were predicted to change the encoded amino acid. However, PCR-SSCP and nucleotide sequencing analysis of the paired blood samples and of an extended sample size of a total of 224 chromosomes indicated that these SSCP patterns represent constitutional rare polymorphisms with a frequency between 0.005 and 0.023. Because the majority of A-T mutations are null mutations and none of the ATM alleles found in breast cancer samples would lead to the truncation of the translation product, we conclude that, in this initial sample of sporadic breast cancer patients, there was no evidence for an increased number of A-T carriers. In addition, because no somatic mutations were found, our study rules out the ATM gene as the frequently altered tumor suppressor gene at 11q23.
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474
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Erkman L, McEvilly RJ, Luo L, Ryan AK, Hooshmand F, O'Connell SM, Keithley EM, Rapaport DH, Ryan AF, Rosenfeld MG. Role of transcription factors Brn-3.1 and Brn-3.2 in auditory and visual system development. Nature 1996; 381:603-6. [PMID: 8637595 DOI: 10.1038/381603a0] [Citation(s) in RCA: 407] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The neurally expressed genes Brn-3.1 and Brn-3.2 (refs 1-6) are mammalian orthologues of the Caenorhabditis elegans unc-86 gene that constitute, with Brn-3.0 (refs 1-3,8,9), the class IV POU-domain transcription factors. Brn-3.1 and Brn-3.2 provide a means of exploring the potentially distinct biological functions of expanded gene families in neural development. The highly related members of the Brn-3 family have similar DNA-binding preferences and overlapping expression patterns in the sensory nervous system, midbrain and hindbrain, suggesting functional redundancy. Here we report that Brn-3.1 and Brn-3.2 critically modulate the terminal differentiation of distinct sensorineural cells in which they exhibit selective spatial and temporal expression patterns. Deletion of the Brn-3.2 gene causes the loss of most retinal ganglion cells, defining distinct ganglion cell populations. Mutation of Brn-3.1 results in complete deafness, owing to a failure of hair cells to appear in the inner ear, with subsequent loss of cochlear and vestibular ganglia.
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475
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Luo L, Wu SZ, Chen XQ, Li MX, Pullum TW. A follow-up study of first trimester induced abortions at hospitals and family planning clinics in Sichuan province, China. Contraception 1996; 53:267-73. [PMID: 8724615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Four-thousand women aged 18-40 underwent an early induced abortion at hospitals and family planning clinics in six counties in Sichuan province, China, between 1 July 1990 and 30 June 1991. The subjects were followed-up three times, on days 15, 90 and 180 after the operation. Information was obtained about their age, parity, contraceptive use, social behaviors, and gynecological and psychological characteristics before and after the abortion. The results indicate that induced abortion is safe when provided by medically trained personnel in health facilities such as hospitals or clinics. Depressive symptomatology was assessed by the CES-D and SCL-90 scales. The depressive symptoms declined over time. A substantial proportion of the abortions were to unmarried women or resulted from non-use of contraception or contraceptive failure, implying that the incidence of unintended pregnancies and induced abortions could be reduced by more effective and accessible contraception.
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476
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Xue F, Luo L, Sun B, Zou Q. [The pharmacokinetics of pancuronium bromide in infants, children and adults]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1996; 18:121-5. [PMID: 9208601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Twenty-four patients scheduled for elective plastic surgery were selected to study the pharmacokinetics of pancuronium bromide under enflurane anesthesia. The patients were divided into three groups by their ages; Group 1 consisted of 5 infants (0.75-2.95 years); Group 2 contained 13 children (4-14 years); Group 3 included 6 adults (16-27 years). An improved fluorimetric assay was used to measure the plasma concentrations of pancuronium bromide after administration of pancuronium bromide at a dose of 100 micrograms/kg. The results showed that the disposition of pancuronium bromide may be best described mathematically by a two-compartment open model in all patients. The younger the patients, the larger the distribution volumes and the higher the Cl. There were significant differences among the three groups with regard to V1, V2, Vdss, Cl, AUC. The T1/2 beta and MRT were longer in Group 1 than in Group 2 and Group 3.
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477
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Aronson B, Enmon JL, Izenwasser S, Katz JL, Kelkar SV, Luo L, Nolan SP, Trudell ML. Synthesis and ligand binding of eta(6)-(2beta-carbomethoxy-3beta-phenyltropane) transition metal complexes. J Med Chem 1996; 39:1560-3. [PMID: 8691489 DOI: 10.1021/jm9508797] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The transition metal complexes [eta(6)- (2beta-carbomethoxy-3beta-phenyltropane)]tricarbonylchromium (3) and [eta(6)-(2beta-carbomethoxy-3beta-phenyltropane)] [eta(5)-(pentamethylcyclopentadienyl)]ruthenium(II)triflate (4) were synthesized from 2beta-carbomethoxy-3beta-phenyltropane (2, WIN 35,065) to further elucidate the influence of substituents on the 3beta-aryl on the affinity of the ligand for cocaine-binding sites at the dopamine transporter. The compounds were tested for their ability to displace bound [(3)H]WIN 35,428 (5) from rat caudate putamen tissue and for their ability to inhibit [(3)H]dopamine uptake. The binding affinity for 3 was 2-fold greater than those observed for cocaine (1) and 2, while the binding affinity for 4 was found to be 100-fold less than those of 1 and 2. In addition, 3 was equipotent with 1 and 2 in [(3)H]dopamine uptake inhibition studies, while 4 was 10-fold less potent. The potencies of the complexes 3 and 4 correlated well with the structure-activity relationships of other 2beta-carbomethoxy-3beta-aryltropane derivatives. These data further support a pharmacophore model in which the region occupied by the aryl ring is a lipophilic pocket with electropositive character.
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478
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Xue F, Sun B, Zou Q, Luo L. Effects of enflurane and isoflurane anesthesia on the pharmacokinetics of pancuronium in adult patients. Chin Med J (Engl) 1996; 109:233-7. [PMID: 8758316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE To evaluate the effects of 1 MAC of enflurane or isoflurane anesthesia on the pharmacokinetics of pancuronium. METHODS Eighteen adult patients undergoing the elective plastic surgery were randomly divided equally into 3 groups, namely, Group 1 (control group), Group 2 (enflurane group) and Group 3 (isoflurane group). Anesthesia was maintained with thiopental and 67% N2O-O2 in Group 1, 1 MAC enflurane in Group 2 and 1 MAC isoflurane in Group 3. After administration of a bolus of pancuronium 100 micrograms/kg, an improved fluorimetric assay was used to determine the serum concentrations of pancuronium and the pharmacokinetic variables of pancuronium were calculated with a 3P87 program. RESULTS The disposition of pancuronium may be well described mathematically by a two-compartment open model. The results showed that in comparison with the control group, patients in Group 2 and Group 3 had a longer T1/2 beta and MRT. The patients in Group 2 had the slower K10 and lower CL than those in the control group. There were no significant differences among the three groups in T1/2 alpha, V1, V2, Vdss, V beta, K21, K12 and AUC. CONCLUSION During enflurane and isoflurane anesthesia, CL of pancuronium decreased, and T1/2 beta and MRT of pancuronium were prolonged in our patients, so duration of the effective plasma concentrations of pancuronium was much longer. As a result, the effects of enflurane and isoflurane of the pharmacokinetics of pancuronium may be part of reason why two drugs extended the duration of neuromuscular depression produced by pancuronium.
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479
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Luo L, Hensch TK, Ackerman L, Barbel S, Jan LY, Jan YN. Differential effects of the Rac GTPase on Purkinje cell axons and dendritic trunks and spines. Nature 1996; 379:837-40. [PMID: 8587609 DOI: 10.1038/379837a0] [Citation(s) in RCA: 387] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Neurons contain distinct compartments including dendrites, dendritic spines, axons and synaptic terminals. The molecular mechanisms that generate and distinguish these compartments, although largely unknown, may involve the small GTPases Rac and Cdc42, which appear to regulate actin polymerization. Having shown that perturbations of Rac1 activity block the growth of axons but not dendrites of Drosophila neurons, we investigated whether this also applies to mammals by examining transgenic mice expressing constitutively active human Rac1 in Purkinje cells. We found that these mice were ataxic and had a reduction of Purkinje-cell axon terminals in the deep cerebellar nuclei, whereas the dendritic trees grew to normal height and branched extensively. Unexpectedly, the dendritic spines of Purkinje cells in developing and mature cerebella were much reduced in size but increased in number. These 'mini' spines often form supernumerary synapses. These differential effects of perturbing Rac1 activity indicate that there may be distinct mechanisms for the elaboration of axons, dendrites and dendritic spines.
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480
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Vorechovský I, Luo L, Prudente S, Chessa L, Russo G, Kanariou M, James M, Negrini M, Webster AD, Hammarström L. Exon-scanning mutation analysis of the ATM gene in patients with ataxia-telangiectasia. Eur J Hum Genet 1996; 4:352-5. [PMID: 9043869 DOI: 10.1159/000472231] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Using a polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) assay, which amplifies individually all coding exons of the ATM gene deficient ataxia-telangiectasia (A-T), we have analyzed 10 patients with A-T for ATM mutations. Mutation were detected in 9 patients. We describe the first ATM mutation in the splice junction found in the 5' splice site of intron 17, leading to exon skipping. However, most mutations were small deletions or insertions resulting in premature termination of the translation product. The development of DNA-based methods for detection of unknown mutations and further characterization of ATM mutation pattern will facilitate identification of A-T carriers and assessment of their cancer risk.
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481
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Luo L, Jan L, Jan YN. Small GTPases in axon outgrowth. PERSPECTIVES ON DEVELOPMENTAL NEUROBIOLOGY 1996; 4:199-204. [PMID: 9168202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We propose that small GTPases in the Rho/Rac/Cdc42 subfamily play a central role in signaling pathways from cell surface receptors to actin cytoskeleton changes in the growth cone. The proposal is based upon the following evidence. First, the Rho/Rac/Cdc42 subfamily GTPases have been shown to regulate various aspects of cytoskeletal organization from budding yeast to mammalian fibroblasts. Second, perturbation of GTPase activities of Rac and Cdc42 in neurons by constitutively active and dominant negative mutants results in specific defects in axon and dendrite outgrowth. In addition to reviewing existing experimental evidence, we will discuss the implications of such a model and the potential relationship with other signaling pathways.
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482
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Luo L, Wiesenfeld-Hallin Z. Differential effects of pre-treatment with intrathecal or intravenous morphine on the prevention of spinal cord hyperexcitability following sciatic nerve section in the rat. Acta Anaesthesiol Scand 1996; 40:91-5. [PMID: 8904265 DOI: 10.1111/j.1399-6576.1996.tb04393.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effect of intrathecal (i.t.) and intravenous (i.v.) morphine on spinal hyperexcitability following unilateral section of the sciatic nerve was studied in decerebrate, spinalized, unanesthetized rats. Sciatic nerve section evoked a biphasic, prolonged hyperexcitability of the flexor reflex. Either i.v. (0.2, 1 or 10 mg center dot kg-1) or i.t. (3 or 10 mu g) morphine was administered prior to sciatic nerve section. All doses of morphine significantly depressed the baseline flexor reflex and abolished the less intense prolonged second component of reflex hyperexcitability. One and 10, but not 0.2, mg center dot kg-1 i.v. morphine significantly depressed the first phase of spinal cord sensitization. However, both 3 mu g and 10 mu g i.t. morphine were significantly more effective than i.v. morphine in suppressing spinal cord hyperexcitability. The present results suggest that moderate doses of i.t. morphine decrease spinal hyperexcitability following nerve transection more than even extremely large i.v. doses. The poorer effect of i.v. morphine on preventing spinal hyperexcitability may be due to low spinal concentration after systemic administration.
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483
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Vorechovský I, Luo L, de Saint Basile G, Hammarström L, Webster AD, Smith CI. Improved oligonucleotide primer set for molecular diagnosis of X-linked agammaglobulinaemia: predominance of amino acid substitutions in the catalytic domain of Bruton's tyrosine kinase. Hum Mol Genet 1995; 4:2403-5. [PMID: 8634718 DOI: 10.1093/hmg/4.12.2403] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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484
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Furuta H, Mori N, Luo L, Ryan AF. Detection of mRNA encoding guanylate cyclase A/atrial natriuretic peptide receptor in the rat cochlea by competitive polymerase chain reaction and in situ hybridization. Hear Res 1995; 92:78-84. [PMID: 8647748 DOI: 10.1016/0378-5955(95)00203-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Expression of mRNA encoding guanylate cyclase A (GC-A)/atrial natriuretic peptide (ANP) receptor in the rat cochlea was examined by polymerase chain reaction (PCR) and in situ hybridization (ISH). After reverse-transcription, PCR amplification, subcloning, and sequencing, we found that GC-A mRNA with sequence identical to that previously cloned from the rat brain (Chinkers et al., 1989) was expressed in the rat spiral ligament as well as in the spiral ganglion. However, GC-A mRNA was not detected in the stria vascularis. Competitive PCR using internal standard DNAs indicated that the expression of GC-A in the cochlea occurred at a level approximately 16 times less than that measured in kidney cortex. ISH histochemistry using a 35S-labeled antisense riboprobe showed the highest level of expression of GC-A mRNA to be in oligodendrocytes of the cochlear nerve root. The results suggest that ANP may play a role in the cochlear nerve function.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Cloning, Molecular
- Cochlea/enzymology
- Cochlea/metabolism
- Cochlear Nerve/metabolism
- DNA Primers/chemistry
- DNA, Complementary/chemistry
- DNA, Complementary/metabolism
- Female
- Gene Expression Regulation, Enzymologic/genetics
- Guanylate Cyclase/genetics
- Guanylate Cyclase/metabolism
- In Situ Hybridization
- Kidney Cortex/enzymology
- Kidney Cortex/metabolism
- Microscopy, Fluorescence
- Molecular Sequence Data
- Oligonucleotides, Antisense/chemistry
- Oligonucleotides, Antisense/metabolism
- Polymerase Chain Reaction
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Receptors, Atrial Natriuretic Factor/genetics
- Receptors, Atrial Natriuretic Factor/metabolism
- Sequence Homology, Nucleic Acid
- Spiral Ganglion/metabolism
- Stria Vascularis/metabolism
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485
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Calafat AM, Taoka S, Puckett JM, Semerad C, Yan H, Luo L, Chen H, Banerjee R, Marzilli LG. Structural and electronic similarity but functional difference in methylmalonyl-CoA mutase between coenzyme B12 and the analog 2',5'-dideoxyadenosylcobalamin. Biochemistry 1995; 34:14125-30. [PMID: 7578009 DOI: 10.1021/bi00043a017] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The cofactor analog 2',5'-dideoxyadenosylcobalamin (ddAdoCbl) differs from the natural cofactor coenzyme B12 [5'-deoxyadenosylcobalamin (dAdoCbl)] by lacking only one oxygen atom. The 1H and 13C NMR spectra of ddAdoCbl have been assigned unambiguously by homonuclear and heteronuclear 2D NMR techniques. The 1H, 13C, and 31P chemical shift values for ddAdoCbl were compared with those of another organocobalamin, namely dAdoCbl. This assessment shows that the analog is very similar both electronically and structurally to the natural cofactor. The effectiveness of ddAdoCbl as a cofactor for both the human and Propionibacterium shermanii methylmalonyl-CoA mutases was compared with that of the natural cofactor. ddAdoCbl was found to be a competitive inhibitor with respect to dAdoCbl. Similar binding affinities to both enzymes were found for both the ddAdoCbl analog and the natural cofactor. However, in the presence of ddAdoCbl, the rate of conversion of methylmalonyl-CoA to succinyl-CoA was only 1-2% of that seen with the natural cofactor. There were no changes with time in the visible absorption spectrum of the bound cofactor analog in the presence of substrate, suggesting that the Co-C bond was not cleaved. The CD (circular dichroism) spectra of dAdoCbl and ddAdoCbl are very similar, consistent with the NMR results. The CD spectral changes upon binding to P. shermanii methylmalonyl-CoA mutase are large compared to those reported on the binding of dAdoCbl to ethanolamine ammonia lyase. Furthermore, the CD spectra of both enzyme-bound cobalamins are very similar, suggesting that similar changes in the conformation or structure in these cobalamins occur on binding to the enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
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486
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Luo L, Brumm D, Ryan AF. Distribution of non-NMDA glutamate receptor mRNAs in the developing rat cochlea. J Comp Neurol 1995; 361:372-82. [PMID: 8550886 DOI: 10.1002/cne.903610303] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In situ hybridization was used to document the distribution of mRNA encoding six subunit isoforms of non-N-methyl D-aspartic acid (NMDA) glutamate receptors (GluR1, GluR2, GluR3, GluR4, GluR5 and GluR6) in the inner ears of embryonic, postnatal and adult rats. GluR2 and GluR3 expression in the spiral ganglion appeared well before birth, and reached adult levels several days before the onset of function in the cochlea. In the spiral limbus, expression of GluR2 and GluR3 mRNA reached very high levels at around the time of birth, then declined after a few days. Low levels of GluR1, GluR4 and GluR6 expression were detected in various tissues of the cochlea during development. In the adult cochlea, GluR expression was limited to GluR2 and GluR3 mRNAs in the spiral ganglion neurons and GluR2 mRNA in fibrocytes of the spiral limbus, a non-neural tissue. The ontogenetic expression of additional GluR subunit genes and their appearance in different cochlear tissues could reflect different roles for these genes during development, or less precise regulation of gene expression within the GluR family. In particular, the very high levels of GluR gene expression in the spiral limbus during the perinatal period support a non-neural function, perhaps as cell surface receptors during tissue differentiation.
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487
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Eaton S, Auvinen P, Luo L, Jan YN, Simons K. CDC42 and Rac1 control different actin-dependent processes in the Drosophila wing disc epithelium. J Biophys Biochem Cytol 1995; 131:151-64. [PMID: 7559772 PMCID: PMC2120599 DOI: 10.1083/jcb.131.1.151] [Citation(s) in RCA: 163] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cdc42 and Rac1 are members of the rho family of small guanosinetriphosphatases and are required for a diverse set of cytoskeleton-membrane interactions in different cell types. Here we show that these two proteins contribute differently to the organization of epithelial cells in the Drosophila wing imaginal disc. Drac1 is required to assemble actin at adherens junctions. Failure of adherens junction actin assembly in Drac1 dominant-negative mutants is associated with increased cell death. Dcdc42, on the other hand, is required for processes that involve polarized cell shape changes during both pupal and larval development. In the third larval instar, Dcdc42 is required for apico-basal epithelial elongation. Whereas normal wing disc epithelial cells increase in height more than twofold during the third instar, cells that express a dominant-negative version of Dcdc42 remain short and are abnormally shaped. Dcdc42 localizes to both apical and basal regions of the cell during these events, and mediates elongation, at least in part, by effecting a reorganization of the basal actin cytoskeleton. These observations suggest that a common cdc42-based mechanism may govern polarized cell shape changes in a wide variety of cell types.
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488
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Luo L, Ji RR, Zhang Q, Iadarola MJ, Hökfelt T, Wiesenfeld-Hallin Z. Effect of administration of high dose intrathecal clonidine or morphine prior to sciatic nerve section on c-Fos expression in rat lumbar spinal cord. Neuroscience 1995; 68:1219-27. [PMID: 8544995 DOI: 10.1016/0306-4522(95)00197-q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effects of moderate and high intrathecal doses of clonidine, an alpha 2 adrenoceptor agonist, or a high dose of morphine on sciatic nerve section-induced expression of c-Fos-like immunoreactivity was studied in laminae I and II of the dorsal horn and laminae VIII and IX of the ventral horn of rat lumbar spinal cord. c-Fos-like immunoreactivity was examined by immunohistochemistry in normal rats (group 1), rats implanted with an intrathecal catheter with its tip on the lumbar spinal cord (group 2), injected with 10 micrograms (group 3) or 50 micrograms (group 4) clonidine intrathecally 3 h before being killed. In other groups, saline, 10 or 50 micrograms clonidine or 30 micrograms morphine was injected 1 h before unilateral nerve section, and the expression of c-Fos-like immunoreactivity was examined 2 h after axotomy. Few labeled neurons were found in normal controls. The intrathecal catheter itself caused a significant increase in bilateral c-Fos-like immunoreactivity in spinal dorsal and ventral horn compared to normals. The level of c-Fos-like immunoreactivity after 10 or 50 micrograms intrathecal clonidine was similar as in the intrathecal catheter group. Sciatic nerve section caused a significant ipsilateral increase in c-Fos-like immunoreactivity in the dorsal horn compared to the intact side in rats injected with saline. Pretreatment with 10 or 10 micrograms clonidine did not reduce sciatic nerve section-induced expression of c-Fos-like immunoreactivity, but instead caused a significant bilateral increase in c-Fos-like immunoreactivity.(ABSTRACT TRUNCATED AT 250 WORDS)
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489
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Said TK, Luo L, Medina D. Mouse mammary hyperplasias and neoplasias exhibit different patterns of cyclins D1 and D2 binding to cdk4. Carcinogenesis 1995; 16:2507-13. [PMID: 7586159 DOI: 10.1093/carcin/16.10.2507] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Deregulated expression of G1 cyclins D1 and D2 is a feature of some neoplasias. This study examined the altered expression of D1 and D2 cyclins, both the total pool and as associated with cdk4 and cdk2, at different stages of mouse mammary tumorigenesis. Three different mammary hyperplastic outgrowth lines, TM2, TM10 and TM12, and their respective tumors were examined. Increasing levels of the cyclin D1 protein pool, D1 binding to cdk4 and cdk2 and cdk4 kinase activity were closely correlated with tumorigenesis. In constrast, cyclin D2 binding to cdk4 was predominant in hyperplasias and much less in tumors, where cyclin D1 became predominant. However, the cyclin D2 pool showed increases of 15-65 times in hyperplasias compared with normal gland and further increases of 11-15 times in two of three different tumors. The message level for cyclin D1 increased only 2-3 times in tumors compared with normal gland. Cyclin D2 mRNA was highest in normal tissue and decreased only marginally in tumors. These results suggest that cyclin D2 functions uniquely from cyclin D1 in the early stages of mouse mammary tumor development. Cyclin D2 bound to cdk4 may act to guarantee a low level of kinase activity in hyperplasias and may be an attempt to direct the mammary epithelial cells through differentiation rather than proliferation. This interaction may be one of the negative regulatory mechanisms in the early stages in mouse mammary tumor development, until cyclin D1 totally replaces cyclin D2 binding to cdk4, which would activate the high levels of cdk4 kinase activity observed in neoplasias.
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490
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Abstract
Mu transposition is promoted by an extremely stable complex containing a tetramer of the transposase (MuA) bound to the recombining DNA. Here we purify the Escherichia coli ClpX protein, a member of a family of multimeric ATPases present in prokaryotes and eukaryotes (the Clp family), on the basis of its ability to remove the transposase from the DNA after recombination. Previously, ClpX has been shown to function with the ClpP peptidase in protein turnover. However, neither ClpP nor any other protease is required for disassembly of the transposase. The released MuA is not modified extensively, degraded, or irreversibly denatured, and is able to perform another round of recombination in vitro. We conclude that ClpX catalyzes the ATP-dependent release of MuA by promoting a transient conformational change in the protein and, therefore, can be considered a molecular chaperone. ClpX is important at the transition between the recombination and DNA replication steps of transposition in vitro; this function probably corresponds to the essential contribution of ClpX for Mu growth. Deletion analysis reveals that the sequence at the carboxyl terminus of MuA is important for disassembly by ClpX and can target MuA for degradation by ClpXP in vitro. These data contribute to the emerging picture that members of the Clp family are chaperones specifically suited for disaggregating proteins and are able to function with or without a collaborating protease.
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491
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Fan M, Peng B, Luo L. [Effects of gu chi san on cultured human gingival fibroblasts]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1995; 30:298-300, 320. [PMID: 8728974] [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 present study demonstrates that Gu Chi San is able to increase the bone density in the clinical and animal tests. This study finds that Gu Chi San has no cytotoxicity on HGFs, and 1g/L Gu Chi San extracts can stimulate the mitosis and enhance the DNA synthesis of HGFs. The results indicate that certain substances are present in Gu Chi San.
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492
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Li Y, Luo L. [Relationship between chlamydial infection in female genital tract and tubal infertility]. ZHONGHUA FU CHAN KE ZA ZHI 1995; 30:471-4. [PMID: 8565694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To detect the incidence of chlamydial infection in female genital tract and it's relationship with tubal infertility. METHODS Fourty-eight infertile women underwent laparoscopies were divided into study group (n = 32) and control group (n = 16). Samples were taken from the upper genital tract (including endometrium, tubal fimbriae, peritoneal fluid and pelvic adhesion) and lower genital tract (cervix). The monoclonal direct immunofluorescent method was used to assay chlamydia trachomatis the results of these two groups were compared. RESULTS The positive percentage of cervical clamydial infections between the two groups were not significant lydifferent (P > 0.05). But there showed a significant difference between the two groups if compared by the incidence of the whole genital tract 32.5% and 10.2% (P < 0.01). The tubal positive percentage is 66.7% in the study group. Which is the highest among other locations such as cervix, endometrium, etc (P < 0.05). CONCLUSION This study indicates that fallopian tube is a high prevalent site of chlamydial infection, and chlamydial infection in female genital tract is a principal pathogenic factor of tubal infertility. Early laparoscopy for tubal infertility and chlamydia trachomatis sampling is the key method for early diagnosis and treatment of chlamydia trachomatis.
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493
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Luo L, Ji F, Li H. Fuzzy classification of nucleotide sequences and bacterial evolution. Bull Math Biol 1995; 57:527-37. [PMID: 7537996 DOI: 10.1007/bf02460781] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A new method for reconstructing evolutionary relationship among bacteria by use of rRNA sequence data is proposed. The method is based on the concept of fuzzy classification of probabilities p(i), p(i/j) and p(i/j*) (i = A, G, C, U) of each sequence. The resulting partition tree shares common features of previous works but has some new peculiarities.
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494
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Luo L, Jackson IM. Thyrotropin-releasing hormone and c-fos/c-jun genes are colocalized in rat anterior pituitary cells: stimulation of transcription by glucocorticoids. Endocrinology 1995; 136:2705-10. [PMID: 7750495 DOI: 10.1210/endo.136.6.7750495] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We recently reported that glucocorticoids (GC) enhance the level of TRH peptide and messenger RNA in anterior pituitary cells. However, the regulating mechanism is as yet unclear. The protooncogenes c-fos/c-jun belong to the class of immediate early genes that are activated in neurons by a variety of stimuli, including GC. Fos protein acts as an intracellular third messenger, regulating gene transcription of neurotransmitters. To determine whether c-fos/c-jun are involved in regulating the effect of GC on TRH in rat anterior pituitary cells, the coexpression and nuclear transcription activity of TRH and c-fos/c-jun after dexamethasone (DEX) stimulation (7 days) were investigated. The double labeled in situ hybridization results demonstrated that TRH and c-fos/c-jun are coexpressed in anterior pituitary cells and that DEX (10(-8) M) enhanced the cell intensity for TRH and c-fos/c-jun. The mean cell intensity of treatment vs. control was 2.4-fold for TRH, 1.4-fold for c-fos, and 1.4-fold for c-jun (n = 24; P < 0.01). The Northern blot analysis also showed that DEX increased the messenger RNA level of TRH 5.1-fold (n = 4; P < 0.01), that of c-fos 1.8-fold (n = 5; P < 0.01), and that of c-jun 4.2-fold (n = 4; P < 0.01). The nuclear run-on analysis indicated that DEX increased the nuclear transcription activity of TRH 3.3-fold, that of c-jun 3.2-fold, and that of c-fos 3-fold (n = 3; P < 0.01) vs. the control value. The coexpression of TRH and c-fos/c-jun in anterior pituitary cells as well as the enhancement of transcription after DEX treatment raise the possibility that c-fos/c-jun could mediate the effect of GC on TRH gene transcriptional activity.
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495
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Xue F, Luo L, Tong S, Liao X, Tang G, Deng X. Children's development effecting blood oxygen desaturation following apnea. Chin Med J (Engl) 1995; 108:434-7. [PMID: 7555253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
One hundred and fifty-six children aged from 4 months to 12 years undergoing elective plastic surgery were included in this study. All children were ASA physical status I, under normal development, ranging from 64 to 140 cm in body height and from 6.0 to 41.0 kg in body weight. Following 2-minute preoxygenation, the time when SpO2 dropped to 95% and 90% in apneic period had a close correlation with age, weight and height of children by means of linear and non-linear regression analysis. The smaller the children's weight, the higher the incidence of severe arterial desaturation after reinstitution of manual ventilation with 100% oxygen at SpO2 of 90%. It is suggested that younger children are more susceptible to hypoxemia than older ones during apnea and provided no problem existing other than oxygen delivery, an SpO2 of 95% might be the safe limitation of apnea in pediatric anesthesia induction.
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496
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Luo L, Moore JK, Baird A, Ryan AF. Expression of acidic FGF mRNA in rat auditory brainstem during postnatal maturation. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1995; 86:24-34. [PMID: 7544700 DOI: 10.1016/0165-3806(95)00011-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In situ hybridization was used to investigate the mRNA distribution of acidic and basic fibroblast growth factor (aFGF and bFGF) in the auditory brainstem of neonatal and adult rats. bFGF mRNA was not detected at any age. In adult rats, aFGF mRNA was strongly expressed in the principal neurons of the anteroventral and posteroventral cochlear nuclei, but not in the octopus cells. In the dorsal cochlear nucleus, aFGF mRNA was seen only in scattered smaller vertical cells. aFGF was strongly expressed in the nucleus of the trapezoid body and in all periolivary cell groups, but not in the medial and lateral olivary nuclei. No expression was observed in the lemniscal nuclei or in the central nucleus of the inferior colliculus, but large neurons in the external zone of the colliculus were labeled. Developmentally, low levels of aFGF expression appeared in the cochlear nuclei and olivary nuclei between P0 and P6. This expression increased rapidly during the onset of hearing, between P10 and P14, and reached adult level by P14-P17. Labeling in collicular neurons appeared slightly later. The results suggest that the appearance of strong aFGF mRNA expression is related to the onset of function.
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497
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Abstract
The probability distributions of bases in nucleotide sequences are deduced from the maximum information principle by maximizing the entropy (due to random mutation of bases) under certain constraints (Markovian entropy, G + C content, etc, due to selection). Two formulations are given with respect to different selective constraints. The deviations of theoretical distributions from experimental data are lower than 10% for most sequences. It is shown that the Lagrange multipliers change from species to species systematically--i.e. selective constraints correlate with evolution.
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498
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Luo L, Wiesenfeld-Hallin Z. The effects of pretreatment with tachykinin antagonists and galanin on the development of spinal cord hyperexcitability following sciatic nerve section in the rat. Neuropeptides 1995; 28:161-6. [PMID: 7540733 DOI: 10.1016/0143-4179(95)90111-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effects of acute section of the sciatic nerve on the excitability of the flexor reflex was examined in decerebrate, spinalized, unanaesthetized rats. In control experiments without drugs, the excitability of the flexor reflex was dramatically increased in two phases following axotomy. An early intense, brief reflex hyperexcitability was followed by a less intense, prolonged period of facilitation. The selective NK1 tachykinin receptor antagonist CP-96,345 injected intrathecally at lower (1.2-2.4 nmol) and higher (12 nmol) doses blocked both components of spinal sensitization. The selective NK2 tachykinin receptor antagonist Men 10376 at a dose of 2.4 nmol also reduced both response components, as did the same dose of the inhibitory neuropeptide galanin. Thus, antagonists of excitatory neuropeptides released during and after nerve section, such as substance P and neurokinin A, can block the spinal response to peripheral nerve injury. Furthermore, the inhibitory neuropeptide galanin also reduced spinal cord sensitization.
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499
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Zhang S, Xu G, Luo L. [Enhancing effects of the supernatant of pulmonary alveolar macrophages stimulated by BCG on proliferation on pulmonary fibroblasts]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1995; 18:26-8, 62-3. [PMID: 7600601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The supernatant of pulmonary alveolar macrophages (PAM) stimulated by 7.5-60mg/L of BCG could significantly enhance proliferation of pulmonary fibroblasts (PFB), and the supernatant contained high level of TNF. This result indicated BCG could stimulate PAM to produce TNF in vitro. On the other hand, the supernatant of PAM stimulated by 50mg/L of SiO2 could also enhance proliferation of PFB, but the level of TNF in the supernatant was very low and it demonstrated the ingredient in the supernatant enhancing proliferation was not TNF. TNF showed synergistic effect with this ingredient for enhancing proliferation of PFB. Therefore, TNF produced by tuberculosis bacteria-stimulated PAM might be an important factor enhancing the development of fibrosis of silicotuberculosis.
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500
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Luo L, Wu SZ, Chen XQ, Li MX, Pullum TW. Induced abortion among unmarried women in Sichuan province, China. Contraception 1995; 51:59-63. [PMID: 7750286 DOI: 10.1016/0010-7824(94)00004-g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This report describes the social and demographic characteristics of 457 unmarried women who underwent a first trimester induced abortion at hospitals and family planning clinics in Sichuan province, China. The data show a very low level of medical complications. However, improved access to contraception for unmarried women is needed in order to reduce the incidence of unintended pregnancies and induced abortion.
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