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Deng H, Zeng Y, Lei Y, Zhao Z, Wang P, Li B, Pi Z, Tan B, Zheng Y, Pan W. Serological survey of nasopharyngeal carcinoma in 21 cities of south China. Chin Med J (Engl) 1995; 108:300-3. [PMID: 7789220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
This paper reports the results of serological survey of 318,912 persons for nasopharyngeal carcinoma (NPC) in 21 cities and counties of south China. There were 8,441 persons with positive VCA-IgA antibody (single item positive) of EB virus (EBV), with a rate of 2.65%. In these VCA-IgA positive persons, 287 persons also had positive EA-IgA (double items positive) of EBV. The overall positive rate was 0.09%. 100 cases of NPC were found and 87 of them (87.0%) were in early stage. NPC found in the group with single item positive accounts for 1.19%, but the rate in the group with double items positive was 19.16% (55 cases). In NPC patients with double items positive, 49 cases were in early stage (89.1%). In 100 cases of NPC found, 45 cases appeared with negative EA-IgA, only with positive VCA-IgA, which indicated that for diagnosis of NPC, sensitivity of EA-IgA was lower than that of VCA-IgA, but its specificity was higher. Therefore, both can increase the detecting rate and early diagnosis rate of NPC. The age of people checked varied with different antibody positive rate and NPC detecting rate. The three items showed a positive correlation. The results are compatible with those of the prospective study for NPC in Wuzhou City, Guangxi, China. The method for NPC serological diagnosis can be extended and applied to raise the NPC detecting rate and early diagnosis rate at secondary prevention. And, it is further proved that there is a close relationship between NPC and EBV.
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402
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Hagman KE, Pan W, Spratt BG, Balthazar JT, Judd RC, Shafer WM. Resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents is modulated by the mtrRCDE efflux system. MICROBIOLOGY (READING, ENGLAND) 1995; 141 ( Pt 3):611-22. [PMID: 7711899 DOI: 10.1099/13500872-141-3-611] [Citation(s) in RCA: 280] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The mtr (multiple transferable resistance) system of Neisseria gonorrhoeae determines levels of gonococcal resistance to hydrophobic agents (HAs), including detergent-like fatty acids and bile salts that bathe certain mucosal surfaces. The genetic organization of the mtr system was determined and found to consist of the mtrR gene, which encodes a transcriptional regulator (MtrR), and three tandemly linked genes termed mtrCDE. The mtrCDE genes were organized in the same apparent transcriptional unit, upstream and divergent from the mtrR gene. The mtrCDE-encoded proteins of N. gonorrhoeae were analogous to a family of bacterial efflux/transport proteins, notably the MexABOprK proteins of Pseudomonas aeruginosa and the AcrAE and EnvCD proteins of Escherichia coli, that mediate resistance to drugs, dyes, and detergents. Inactivation of the mtrC gene resulted in loss of the MtrC lipoprotein and rendered gonococci hypersusceptible to structurally diverse HAs; this revealed the importance of the mtr system in determining HAR in gonococci. Further support for a role of the mtrCDE gene complex in determining levels of HAR in gonococci was evident when transformants bearing mutations in the mtrR gene were analysed. In this respect, missense and null mutations in the mtrR gene were found to result in increased levels of MtrC and HAR. However, high levels of MtrC and HAR, similar to those observed for clinical isolates, were associated with a single bp deletion in a 13 bp inverted repeat sequence that intervened the divergent mtrR and mtrC genes. We propose that the 13 bp inverted-repeat sequence represents a transcriptional control element that regulates expression of the mtrRCDE gene complex, thereby modulating levels of gonococcal susceptibility to HAs.
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403
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Cui XH, Pan W, Qi ZT. [Genotyping of hepatitis C virus in patients with hepatocellular carcinoma]. ZHONGHUA YI XUE ZA ZHI 1995; 75:92-3, 126-7. [PMID: 7767776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Forty-two patients with hepatocellular carcinoma (HCC) were examined for hepatitis C virus (HCV) RNA in liver tissues by reverse transcription-polymerase chain reaction (RT PCR). Typing of HCV liver samples of 18 patients was dependent on the amplification of NS5 region by PCR using type-specific primers. Type-II was found in 14 of the 18 patients (78%), 7 of the 18 patients (39%) and 4 of the 18 patients (22%) were positive for type-II and I and for type-II and III or IV (III/IV), respectively. Type V or VI (V/VI) infection was not observed. These data indicate that HCV type-II may be the major type in HCC patients with HCV infection in China, and some patients can be coinfected with type-II and I or III/IV.
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404
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Maitra SR, Pan W, Lange AJ, el-Maghrabi MR, Abumrad NN, Pilkis SJ. Glucose-6-phosphatase gene expression and activity are modulated in hemorrhagic shock: evidence for a new heat-sensitive activator. Biochem Biophys Res Commun 1994; 204:716-24. [PMID: 7980534 DOI: 10.1006/bbrc.1994.2518] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Decreased hepatic fructose 2,6-bisphosphate levels were observed in the early phase of hemorrhagic shock. The lower sugar bisphosphatae level was a result of increased phosphoenolpyruvate levels and decreased glucose-6-phosphate and fructose-6-phosphate levels. The decreased glucose-6-phosphate levels correlated with increased activity of liver glucose-6-phosphatase and a concomitant 2.5-fold increase in glucose-6-phosphatase mRNA abundance. In addition, protein-free filtrate from hemorrhagic shock rats, but not from control rats, increased glucose-6-phosphatase activity. However, when control and hemorrhagic shock protein-free filtrates were heated, they both increased the glucose-6-phosphatase activity of the respective microsomes to the same extent. It is concluded that the early hyperglycemic phase of hemorrhagic shock is due to enhanced glucose-6-phosphatase gene expression and activity and the generation of a heat sensitive activator of the enzyme.
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405
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Pan W, Zhang L, Xia Y. The difference in EEG theta waves between concentrative and non-concentrative qigong states--a power spectrum and topographic mapping study. J TRADIT CHIN MED 1994; 14:212-8. [PMID: 7799657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The differences in EEG theta waves between concentrative and non-concentrative Qigong states were studied by means of power spectrum analysis and EEG mapping. The adult subjects included 20 practitioners of concentrative Qigong, 30 practitioners of non-concentrative Qigong and 23 control subjects. The results showed frontal mid-line theta rhythm was related to concentrative Qigong state. As the theta rhythm has been suggested to be one of the normal EEG patterns occurring in mental concentration, it is concluded that the theta rhythm is an indicator of mental concentration during Qigong state. This finding clarifies the implication of the theta rhythms appearing in Qigong and other meditation.
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406
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Lange AJ, Argaud D, el-Maghrabi MR, Pan W, Maitra SR, Pilkis SJ. Isolation of a cDNA for the catalytic subunit of rat liver glucose-6-phosphatase: regulation of gene expression in FAO hepatoma cells by insulin, dexamethasone and cAMP. Biochem Biophys Res Commun 1994; 201:302-9. [PMID: 8198588 DOI: 10.1006/bbrc.1994.1702] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
cDNA clones coding for the catalytic subunit of rat liver glucose-6-phosphatase (EC 3.1.3.9) were isolated from a rat liver cDNA library in lambda gt11 phage. The sequence of the cDNA and the amino acid sequence derived from it were greater than 90% identical to the corresponding sequences for the mouse and human forms of liver glucose-6-phosphatase. Northern blot analysis of RNA from FAO hepatoma cells revealed that dexamethasone induced the glucose-6-phosphatase mRNA while insulin suppressed its expression. When both hormones were added together insulin completely suppressed the effect of glucocorticoid. cAMP addition alone decreased the abundance of glucose-6-phosphatase mRNA. The results demonstrate multihormonal regulation of gene expression of hepatic glucose-6-phosphatase and support a dominant role for insulin.
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407
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Abstract
Panda conservation in China has been plagued by controversy and cultural and political differences. But international cooperation, together with new studies identifying the main threats, offer renewed hope for the species' survival.
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408
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Abstract
The mtrR gene of Neisseria gonorrhoeae controls the level of susceptibility to hydrophobic antibiotics and detergents. The mtrR gene was cloned and shown to encode a putative transcriptional repressor. The mtr region was homologous to the envCD and acrAB regions of Escherichia coli, which are also involved in susceptibility to hydrophobic compounds. A homologous repressor protein was encoded by a previously unrecognized open reading frame within both the envCD and acrAB regions. Deletion of mtrR resulted in increased resistance to antibiotics and detergents: the mtrR mutations in two penicillin-resistant clinical isolates resulted in a change of His-105 to Tyr. We propose that the mtrR repressor allows gonococci to regulate the permeability of its cell envelope in response to environmental signals, so that they can grow in the presence of toxic faecal lipids in the rectum as well as in the genital tract.
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409
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Pan W, Doniach S. Effect of self-organized criticality on magnetic-flux creep in type-II superconductors: A time-delayed approach. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:1192-1199. [PMID: 10010426 DOI: 10.1103/physrevb.49.1192] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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410
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Maitra SR, Pan W, Geller ER, Henry MC. Alterations in renal gluconeogenesis and blood flow during hemorrhagic shock. CIRCULATORY SHOCK 1993; 41:67-70. [PMID: 8242881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The role of renal gluconeogenesis following hemorrhagic shock was studied. Hemorrhagic shock was induced in fasted, anesthesized rats by reduction of blood pressure to 40 mm Hg for either 30 or 150 min. Plasma samples were obtained for plasma glucose determination, and right renal arterial blood flow was determined with the help of an ultrasonic transit time blood flowmeter in hemorrhagic shock and control rats. The kidney was perfused via the renal artery with 37 degrees C oxygenated, glucose-free Krebs-Henseleit solution in the presence of 100 microM phloridzin to inhibit the cellular reuptake of glucose. Renal glucose production was determined by measuring glucose in both renal vein effluent and urine. After 30 min of equilibration, 5 mM lactate and 0.5 mM pyruvate were added to the perfusate as a gluconeogenic substrate, and effluent samples were collected after 5, 10, and 15 min. Moderate hyperglycemia was observed in vivo following 30 min of hemorrhagic shock, and significant hypoglycemia (P < .05) was observed following 150 min of hemorrhagic shock. Renal arterial flow was significantly decreased at 30 min (P < .05) and 150 min (P < .05) of hemorrhagic shock. Renal glucose production with and without substrate after 30 min of hemorrhagic shock was similar compared to control. Renal glucose production after 150 min of hemorrhagic shock was significantly decreased (P < .05) compared to control.(ABSTRACT TRUNCATED AT 250 WORDS)
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411
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Maitra SR, Pan W, Geller ER. Effect of diltiazem on altered glucose regulation during endotoxic shock. J Surg Res 1993; 55:201-4. [PMID: 8412100 DOI: 10.1006/jsre.1993.1130] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Endotoxic shock is associated with profound metabolic alterations including hypoglycemia and hyperlactiacidemia. We studied hepatic glucose production and the role of diltiazem in affecting these metabolic alterations in a rat model of endotoxic shock. Fasted rats were intravenously injected with saline, endotoxin (20 mg/kg), endotoxin (20 mg/kg) plus diltiazem (1.2 mg/kg), or saline plus diltiazem. Five hours after the injections, the rats were anesthetized and blood samples were obtained for plasma glucose and lactate. The livers of all rats were then perfused in situ with an oxygenated 37 degrees C glucose-free Hanks' balanced salt solution at a rate of 30 ml/min via the portal vein and effluent was collected from the inferior vena cava. After 30 min equilibration, 5 mM lactate was added to the perfusate as a gluconeogenic substrate. Endotoxic groups exhibited hypoglycemia (64.5 +/- 12.7 mg/dl) and hyperlacticacidemia (4.3 +/- 0.63 mM). Diltiazem administration improved the hypoglycemia (96.9 +/- 9.1 mg/dl) and attenuated the hyperlacticacidemia (2.2 +/- 0.7 mM) in the endotoxic group. Gluconeogenic stimulation with lactate was demonstrated in both the control (18.1 +/- 2.3 vs 12.8 +/- 1.86 microns/g/hr, P < .05) and endotoxic (16.6 +/- 2.3 vs 9.8 +/- 1.1, P < .05) groups. However, stimulation in the endotoxic groups was significantly less compared with control. Gluconeogenic stimulation in the endotoxic group was unaffected after diltiazem administration. These data suggest that diltiazem treatment in endotoxic shock improves hypoglycemia and attenuates hyperlacticacidemia. These metabolic alterations are not associated with an improvement in substrate-specific stimulation of gluconeogenesis.
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412
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Maitra SR, Geller ER, Pan W, Kennedy PR, Higgins LD. Altered cellular calcium regulation and hepatic glucose production during hemorrhagic shock. CIRCULATORY SHOCK 1992; 38:14-21. [PMID: 1394859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The relationship between intracellular Ca2+ and glucose production in the liver during early and late states of hemorrhagic shock was studied. Rats were anesthetized with intraperitoneal sodium pentobarbital and both femoral arteries and one femoral vein were cannulated. Rats were divided into two groups. One group was subjected to hemorrhagic shock by rapid withdrawal of blood to a mean arterial pressure of 40 mm Hg and maintained in shock for either 30 or 150 min. Rats in the control group were observed for the same time period. Hepatic glucose production was evaluated in both groups by a nonrecirculating liver perfusion model with and without lactate as a substrate. Intracellular free Ca2+ in hepatocytes was measured using the Ca2+ selective indicator Fura-2, under basal and epinephrine-stimulated conditions. Hyperglycemia and hyperlacticacidemia were observed in vivo at 30 min of hemorrhagic shock, whereas hypoglycemia and hyperlacticacidemia were observed at 150 min of shock. Hepatic glucose production in isolated perfused livers was significantly depressed at 30 min in animals subjected to shock (P less than 0.05). Lactate-induced glucose production was significantly attenuated at 30 and 150 min (P less than 0.05). Basal Ca2+, in isolated hepatocytes, at 30 and 150 min of hemorrhagic shock was significantly (P less than 0.05) higher than in controls. The hemorrhagic shock rat hepatocytes failed to evaluate intracellular free Ca2+ upon stimulation with 10(-5) M epinephrine. These results demonstrate that hemorrhagic shock is associated with an increase in hepatocyte intracellular Ca2+ concentration along with attenuation of hormone-mediated mobilization of calcium and substrate specific stimulation of hepatic glucose production.
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413
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Shi D, He G, Cao S, Pan W, Zhang HZ, Yu D, Hung MC. Overexpression of the c-erbB-2/neu–encoded p185 protein in primary lung cancer. Mol Carcinog 1992; 5:213-8. [PMID: 1350198 DOI: 10.1002/mc.2940050308] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The c-erbB-2/neu gene encodes a transmembrane protein of 185 kDa (p185) with tyrosine kinase activity and extensive sequence homology to epidermal growth factor receptor. Amplification and overexpression of the c-erbB-2/neu gene has been shown in certain human tumors and is postulated to be important in human carcinogenesis. High levels of expression of the c-erbB-2/neu gene have been reported in non-small-cell lung cancer (NSCLC) cell lines and primary tumors from the United States. Since geographical and cultural factors may contribute to the development of certain types of cancer, we examined p185 examined p185 expression in 120 tumors from Chinese patients with lung cancers of different cell types and used immunohistochemical staining to determine the extent and general significance of p185 expression in human primary lung cancer. Our results demonstrate that 58.8% of the NSCLCs expressed p185 and that expression of p185 was observed only in NSCLC and not in small-cell lung cancers. Thirty-three of 41 adenocarcinomas and 24 of 55 squamous cell carcinomas among the NSCLCs examined were found to express p185 at levels different from those of normal lung. For the squamous cell carcinomas, p185 expression was correlated with lymph node metastasis (P less than 0.01), but for the adenocarcinomas, it was not (P greater than 0.05). In addition, expression of p185 in NSCLC was significantly more frequent in patients in advanced clinical stages. Our findings indicate that p185 expression is a frequent event and a general phenomenon in NSCLC and is correlated with poor clinical prognostic indicators, suggesting that expression of p185 may be of potential prognostic importance in NSCLC.
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414
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Pan W, Goldstein A. Optimizing the performance of Doppler blood-flow probes in extra-corporeal circuits. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1990; 37:159-163. [PMID: 18285028 DOI: 10.1109/58.55305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A theory is developed to improve the signal-to-noise (S/N) ratio of clamp-on Doppler blood-flow probes by optimizing their operating frequency for the tubing utilized in extra-corporeal blood circuits. The theoretical results can be used to increase the magnitude of both the S/N and Doppler frequency shift and to produce a greater tolerance of S/N to variations in the dimensions and acoustic parameters of Tygon tubes. It is shown that thin tube walls improve the S/N and reduce the effect of temperature variations on the magnitude of the S/N. Measurements were performed on various Tygon tubes and their acoustic attenuations obtained. These values were used to predict an optimum operating frequency of 1.78 MHz for the de facto standard tubing having 3/32-in wall thickness. If a 1/16-in wall thickness were substituted, then the optimum operating frequency would be 2.67 MHz and the S/N would increase by 14.54 dB.
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415
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Hawkins M, Pan W, Stefanovich P, Radulovacki M. Desensitization of adenosine A2 receptors in the striatum of the rat following chronic treatment with diazepam. Neuropharmacology 1988; 27:1131-40. [PMID: 2849727 DOI: 10.1016/0028-3908(88)90008-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Following prolonged treatment (7 days) with diazepam (10 mg/kg/day, using ALZET mini-osmotic pumps) in rats, the function of adenosine receptors was assessed in specific structures of the brain, using both agonist ligand binding and adenylate cyclase assays. Binding to A1 receptors was quantified using [3H]N6-[(R)-1-methyl-2-phenylethyl] adenosine, a selective ligand at A1 receptors. Differences in the binding of this ligand and that of [3H]5'-N-ethylcarboxamide adenosine, which binds to both A1 and A2 subtypes of receptors with similar affinities, were used to quantify A2 receptors. Treatment with diazepam failed to alter the binding of [3H]N6-[(R)-1-methyl-2-phenylethyl] adenosine in all areas of the brain studied. However, the binding of A2 receptors and A2 receptor-mediated stimulation of adenylate-cyclase were significantly attenuated in striatal membranes from diazepam-treated rats. Thus, the present study indicated that functional adenosine A2 receptors were desensitized after prolonged treatment with diazepam, since decreased agonist binding to A2 receptors paralleled an attenuation in the stimulation by adenosine of the activity of adenylate cyclase, an effect mediated by the A2 receptor. These results further indicate that the changes in adenosine A2 receptors correlated with significant short-lasting alterations in the sleep-wake cycle during the withdrawal of diazepam. The alterations in sleep-wakefulness did not correlate with the effect of diazepam on benzodiazepine receptors since no changes were observed in the binding of benzodiazepine receptors.
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416
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Yu J, Pan W. [Treatment of 134 cases of saddle nose with sulfated silicone rubber at room temperature--preliminary report]. 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 1986; 2:264-6. [PMID: 3151289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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417
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Jiang ZM, Pan W, Fei LM. Choledochoduodenal fistula: a rare complication of duodenal ulcer. Chin Med J (Engl) 1986; 99:782-4. [PMID: 3100150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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418
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Chen JW, Pan W, D'Souza MP, August JT. Lysosome-associated membrane proteins: characterization of LAMP-1 of macrophage P388 and mouse embryo 3T3 cultured cells. Arch Biochem Biophys 1985; 239:574-86. [PMID: 3923938 DOI: 10.1016/0003-9861(85)90727-1] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Lysosome-associated membrane protein (LAMP)-1, a major glycoprotein of mouse embryo 3T3 cells and specifically associated with the lysosomal membrane, has been identified in P388 macrophage cells and compared with the homologous glycoprotein of NIH 3T3 cells. Immunofluorescence microscopy with anit-LAMP-1 monoclonal antibodies shows that the antigen was distributed throughout P388 cells including the ruffled edges or pseudopodia, identical to the pattern of acridine orange accumulation. LAMP-1 was purified from P388 cells by affinity chromatography with 1D4B monoclonal antibody, yielding a homogeneous glycoprotein comprising 0.1% of the total detergent-extracted cell protein. The apparent mass of P388 LAMP-1 was 130,000 to 150,000 compared to the 3T3 glycoprotein of 105,000 to 115,000. Analysis of tryptic peptides indicated that the two purified glycoproteins were highly homologous. Protein synthesis was analyzed in a variety of cell lines by pulse-chase labeling with [35S]methionine; in every case, LAMP-1 was synthesized as a precursor of apparent Mr 92,000, and then converted to heterogeneous mature forms differing in average Mr from 110,000 to 140,000. The basis for these apparent differences in mass was examined by studies of the biosynthesis and oligosaccharide composition of the glycoprotein. Core polypeptides of 45,000 Da were obtained from both HaNIH and P388 cells by treating immunoprecipitates of [35S]methionine pulse-labeled molecules with endoglycosidase H. Cells treated with monensin contained heterogeneous molecules of 80,000 to 85,000 Da. Isoelectric heterogeneity of mature LAMP-1 was markedly reduced by treatment with neuraminidase whereas there was little effect on the apparent molecular weight of the molecules or the differences between the various cell lines. beta-D-Xyloside inhibition of glycosaminoglycan synthesis had little effect on the apparent mass of LAMP-1.
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