1276
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Abstract
The effect of biotin supplementation on turkey breeder hen performance was examined in two experiments. A corn-soybean meal-based breeder diet was supplemented with biotin to provide a low (.178 mg/kg) and high (.75 mg/kg) level of dietary biotin. The diets were fed to female-line hens (Nicholas strain) starting at time of light stimulation (31 and 30 wk of age for Experiments 1 and 2, respectively) for 27 wk. Each diet was fed to four replicate pens of 25 hens each. In Experiment 1, egg production and hatchability of fertile eggs from hens fed the high level of biotin was significantly greater (P < .05) during 50 to 54 wk of age. Egg production and hatchability were improved by 22 and 10%, respectively, from 50 to 54 wk of age. In Experiment 2, reproductive performance was unaffected by biotin level during 33 to 57 wk of age. The higher level of dietary biotin seemed beneficial in supporting later reproductive performance in one of two experiments.
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1277
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Li Y, Chen F, Linskens H, Cresti M. Distribution of unesterified and esterified pectins in cell walls of pollen tubes of flowering plants. ACTA ACUST UNITED AC 1994. [DOI: 10.1007/bf00228487] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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1278
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Su X, Chen F, Hokin LE. Cloning and expression of a novel, highly truncated phosphoinositide-specific phospholipase C cDNA from embryos of the brine shrimp, Artemia. J Biol Chem 1994; 269:12925-31. [PMID: 8175710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A novel, highly truncated form of a cDNA encoding Artemia phosphoinositide-specific phospholipase C (PLC), designated PLC-beta x, was isolated from a brine shrimp cDNA library. The full-length cDNA is of the beta-type, it is 2855 base pairs long, and it contains an open reading frame encoding 489 amino acids. The deduced amino acid sequence of PLC-beta c cDNA shows novel features. It lacks several hundred amino acids at the 5' end, as compared to PLC-beta s in the higher species. It contains conserved domains X and Y, but domain X is highly truncated at the 5' end (only 14-25 conserved amino acids as compared to about 150 amino acids in the higher eukaryotic organisms). Northern blot hybridization showed that the PLC-beta x cDNA corresponds to a 4.4-kilobase mRNA. Northern blot hybridization with a cDNA probe from the 5' end and PCR performed upstream from domain Y showed that PLC-beta x is not a cloning artifact due to fusion of an unrelated clone into the coding region of the PLC-beta homologue. A functional PLC and new protein bands on SDS-PAGE were observed after subcloning full-length PLC-beta x cDNA, as well as a fragment containing the conserved regions, into expression plasmid vectors and transfecting into Escherichia coli. 1 mM lithium markedly stimulated expression in E. coli.
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1279
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Xia H, Chen F, Puett D. A region in the human glycoprotein hormone alpha-subunit important in holoprotein formation and receptor binding. Endocrinology 1994; 134:1768-70. [PMID: 7511092 DOI: 10.1210/endo.134.4.7511092] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Using site-directed mutagenesis of the human glycoprotein hormone alpha-subunit, we have shown that single replacements of Ala36 and Pro38 with Glu and Asp, respectively, result in mutant subunits that do not bind significantly to hCG beta. In contrast, the replacement of Lys44 with Ala did not interfere with hCG beta binding, but the resulting holoprotein failed to exhibit high affinity binding to the LH/CG receptor. These results in conjunction with other data suggest that the region of human alpha between positions 33-45 contains several amino acid residues that participate in subunit binding and others that function in receptor binding.
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1280
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Chen F, Li ZC, Ge RQ, Liu GH, Cai W, Zhang ZD. The measurement of DNA content in Wilms' tumor and its clinical significance. J Pediatr Surg 1994; 29:548-50. [PMID: 8014813 DOI: 10.1016/0022-3468(94)90088-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
DNA content analysis with paraffin-embedded tissue was performed by flow cytometry on extracted nuclei from 42 Wilms' tumors. DNA histograms showed diploid in 13, tetraploid in 12, and aneuploid in 17. The frequency of DNA aneuploid was 40.48%. The 2- and 5-year survival rates were 84% and 75.16%, respectively, for patients with the DNA diploid pattern; the 2- and 5-year DNA aneuploid survival rates were 47.06% and 41.18% (P < .03 and P < .05), respectively. The 2- and 5-year survival rates for DNA tetraploid were in between, both 55.90%. For patients with stage I and II, the difference in the 2- and 5-year survival rates between DNA diploid plus tetraploid and DNA aneuploid was even more significant (P < .004 and P < .002, respectively). Thus, DNA aneuploid is an important indicator of poor prognosis in Wilms' tumor, especially for stages I and II.
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1281
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Su X, Chen F, Hokin L. Cloning and expression of a novel, highly truncated phosphoinositide-specific phospholipase C cDNA from embryos of the brine shrimp, Artemia. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)99964-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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1282
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Kang Z, Chen F, Wang Z. Evaluation of captopril renography with 99mTc-MAG3 in the diagnosis of renovascular hypertension. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1994; 9:49-51. [PMID: 8086635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Eighty-one patients with suspected renovascular hypertension (RVH) were studied using 99mTc-MAG3 renography before and after administration of 25 mg captopril (CAP). Among the 81 cases, 22 were proven by renal arteriography or DSA. The results showed that by using CAP, the sensitivity and specificity of renography in RVH diagnosis increased from 66% to 72% and from 33% to 100%, respectively. We conclude that renography is a simple, noninvasive, sensitive and specific method for screening RVH and is suitable for use in hospitals with no gamma-cameras.
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1283
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Chen F, Nilsson H, Holmér I. Cooling responses of finger in contact with an aluminum surface. AMERICAN INDUSTRIAL HYGIENE ASSOCIATION JOURNAL 1994; 55:218-22. [PMID: 8184801 DOI: 10.1080/15428119491019050] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Skin temperature (T sk) changes and subjective sensations of bare fingers touching a cold aluminum surface were determined in 25 subjects (12 female and 13 male). An 11-cm aluminum cube was placed in a mini-chamber, where chamber air and an aluminum cube were simultaneously cooled to -14, -5, and -1 degrees C, respectively. Subjects inserted their right hands into the chamber and pressed on the cube surface with three fingers with a force of 9.81 N (1 Kp). Exposure lasted until finger-skin temperature reached 0 degree C or was voluntarily ended by the subject. Regression equations with two exponential components were used to describe the relationship between T sk and exposure time. The short time constant (< 1 second) for the first part of the cooling curve is assumed to represent primarily thermocouple dynamics. The long time constant (> 20 seconds) for the second part of the cooling curve is interpreted as representing the rate of heat transfer from the tissues of the finger itself. Gender and cube-surface temperature had no significant effect on any of the time constants. Thermal sensation and pain sensation lacked a good correlation with the contact and T sk and T sk change.
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1284
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Arya S, Chen F, Spycher S, Isenman DE, Shulman MJ, Painter RH. Mapping of amino acid residues in the C mu 3 domain of mouse IgM important in macromolecular assembly and complement-dependent cytolysis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1994; 152:1206-12. [PMID: 8301125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
By analyzing the effects of single site mutations of a TNP-binding mouse IgM we have identified amino acid residues clustered in two regions in the C mu 3 domain that are important in the complement-dependent cytolytic activity of polymeric IgM. Some of the mutations also impaired IgM polymerization. For one of these clusters, D432G, P434A, and P436S, which lies on the fy2 and fy3 strands and their connecting loop, polymerization was little affected and the effect on the cytolytic activity of the polymer fraction was taken to imply direct involvement of the residue in C1 binding. The other cluster, involving residues D356A K361A and D417G, is situated at the other end of the C mu 3 domain closer to the center of the Fc mu disc. The D356A K361A and D417G mutations significantly impaired polymer formation, suggesting that these residues are necessary for proper folding or packing of the C mu 3 domains and may affect cytolysis only indirectly. Some other mutations had little or no effect on polymerization or cytolytic activity (E423A, E527G), whereas some mutations impaired only IgM polymerization without affecting cytolytic activity (D344A, K361A, K443A P544G). In others the defect in polymerization was so profound that only the monomer formed (H430A/N/Q and K438G). Our results also suggest that the C1 binding site of IgM is not strictly homologous to the C1 binding site of IgG. Although mutation of E318 of IgG has been shown to reduce its cytolytic activity, mutation of the homologous residue in IgM, E423, was without effect as were mutations of other flanking-charged residues. Proline at 436 in IgM and 331 in IgG may, however, be a common element.
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1285
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Chang FY, Chen F, Lee SD. Equal efficacy of both cimetidine formulations for the healing of gastric ulcer. Eur J Clin Pharmacol 1994; 46:91-2. [PMID: 8005196 DOI: 10.1007/bf00195924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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1286
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Chen F, Cole P, Wen L, Mi Z, Trapido EJ. Estimates of trace element intakes in Chinese farmers. J Nutr 1994; 124:196-201. [PMID: 8308568 DOI: 10.1093/jn/124.2.196] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Epidemiologic data on the average daily human dietary intake of the trace elements nickel, cadmium, molybdenum and silicon are scarce, worldwide, primarily because foods consumed vary widely over days and seasons. Available full year food allocation records for farmers in rural areas of China provide an unique opportunity to estimate dietary trace elements. In 1988, we measured the concentration of zinc, copper, iron, cadmium, nickel, molybdenum, silicon and selenium in different foods by using food samples collected from 232 villages (distributed among 21 communes). These measurements, combined with the food consumption information from existing food allocation records in each commune for an entire year, allowed us to estimate the average daily consumption of these trace elements by Chinese farmers. With one exception (an association of zinc and esophageal cancer), the variation of dietary trace elements did not show any association with mortality from several common diseases. The estimates for some of the dietary trace elements from some subpopulations were either less or more than current recommendations. No increases in mortality were found, however, from diseases normally associated with either dietary deficiencies or excesses of these elements.
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1287
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Arya S, Chen F, Spycher S, Isenman DE, Shulman MJ, Painter RH. Mapping of amino acid residues in the C mu 3 domain of mouse IgM important in macromolecular assembly and complement-dependent cytolysis. THE JOURNAL OF IMMUNOLOGY 1994. [DOI: 10.4049/jimmunol.152.3.1206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
By analyzing the effects of single site mutations of a TNP-binding mouse IgM we have identified amino acid residues clustered in two regions in the C mu 3 domain that are important in the complement-dependent cytolytic activity of polymeric IgM. Some of the mutations also impaired IgM polymerization. For one of these clusters, D432G, P434A, and P436S, which lies on the fy2 and fy3 strands and their connecting loop, polymerization was little affected and the effect on the cytolytic activity of the polymer fraction was taken to imply direct involvement of the residue in C1 binding. The other cluster, involving residues D356A K361A and D417G, is situated at the other end of the C mu 3 domain closer to the center of the Fc mu disc. The D356A K361A and D417G mutations significantly impaired polymer formation, suggesting that these residues are necessary for proper folding or packing of the C mu 3 domains and may affect cytolysis only indirectly. Some other mutations had little or no effect on polymerization or cytolytic activity (E423A, E527G), whereas some mutations impaired only IgM polymerization without affecting cytolytic activity (D344A, K361A, K443A P544G). In others the defect in polymerization was so profound that only the monomer formed (H430A/N/Q and K438G). Our results also suggest that the C1 binding site of IgM is not strictly homologous to the C1 binding site of IgG. Although mutation of E318 of IgG has been shown to reduce its cytolytic activity, mutation of the homologous residue in IgM, E423, was without effect as were mutations of other flanking-charged residues. Proline at 436 in IgM and 331 in IgG may, however, be a common element.
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1288
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Trapido EJ, Chen F, Davis K, Lewis N, MacKinnon JA. Cancer among Hispanic males in south Florida. Nine years of incidence data. ARCHIVES OF INTERNAL MEDICINE 1994; 154:177-85. [PMID: 8285813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Dade County (Florida) is the largest county in the United States in which a majority of the population is Hispanic. To describe and compare cancer incidence among white and black Hispanic and non-Hispanic males in South Florida and to identify those sites showing important racial-ethnic differences between sub-groups, incidence rates were determined from 9 years of prospective population-based cancer surveillance data. METHODS All incident cancer cases diagnosed among male residents of Dade County for the period January 1, 1981, through December 31, 1989, were obtained from the statewide tumor registry for Florida, the Florida Cancer Data System. Race- and ethnic-specific age-standardized incidence rates and standardized rate ratios to compare rates among racial-ethnic subgroups for each site are presented. RESULTS Compared with white non-Hispanics, white Hispanic males had significantly higher rates of cancers of the liver, gallbladder, nasal cavity, penis, and thyroid; acute lymphocytic leukemia; and Kaposi's sarcoma. Significantly lower rates were found for cancers of the esophagus, stomach, colon, rectum, pancreas, lung, testes, bladder, and kidney, and for mesothelioma, melanoma, non-Hodgkin's lymphoma, and chronic lymphocytic leukemia. Black Hispanics had significantly lower rates only of cancers of the esophagus, lung, and prostate than did black non-Hispanics. CONCLUSION Differences were found in incidence rates by race-ethnicity; while incidence rates for most sites among white Hispanic males were lower than among white non-Hispanics, higher rates for several sites are of particular concern and merit further investigation to determine differences in risk factors and exposures.
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1289
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Chen F, Bazhenov S, Hiltner A, Baer E. Flexural failure mechanisms in unidirectional glass fibre-reinforced thermoplastics. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0010-4361(94)90062-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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1290
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Trivedi P, Hu LF, Chen F, Christensson B, Masucci MG, Klein G, Winberg G. Epstein-Barr virus (EBV)-encoded membrane protein LMP1 from a nasopharyngeal carcinoma is non-immunogenic in a murine model system, in contrast to a B cell-derived homologue. Eur J Cancer 1994; 30A:84-8. [PMID: 8142171 DOI: 10.1016/s0959-8049(05)80024-3] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Epstein-Barr virus (EBV)-encoded LMP1 gene derived from a nude mouse passaged nasopharyngeal carcinoma (NPC) of Chinese origin (C-LMP1) and its B cell (B95-8 prototype)-derived counterpart (B-LMP1) were compared for their ability to induce tumour rejection in a mouse mammary adenocarcinoma system. Each of the two LMP1 genes was introduced individually by retroviral vectors into a non-immunogenic mammary carcinoma line, S6C, that originated in an ACA (H-2f) mouse. Syngeneic ACA mice were immunised for 3 consecutive weeks with irradiated B- or C-LMP1 expressors or control cells. The immunised and control mice were then challenged with graded numbers of viable cells from the corresponding cell line. Only the B-LMP1 expressing cells were highly immunogenic. Up to 10(5) cells were rejected in pre-immunised mice, whereas at least 10(2) cells grew in non-immunised controls. No rejection response was detected against the C-LMP1 expressing cells which grew equally well in control and immunised mice, with a minimum inoculum of 10(2) cells in the majority of the clones. In a previous study, we found numerous sequence differences between B- and C-LMP1. The question of whether any of these differences is related to the non-immunogenicity of C-LMP1 needs further investigation. Meanwhile, our findings raise the possibility that the NPC cells may escape host rejection by the development of a non-immunogenic LMP1 variant under the impact of immunoselection.
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1291
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O'Dorisio MS, Chen F, O'Dorisio TM, Wray D, Qualman SJ. Characterization of somatostatin receptors on human neuroblastoma tumors. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1994; 5:1-8. [PMID: 8123588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Neuroblastoma is the most common extracranial solid tumor of children. Neuroblastoma tumors derive from the neural crest and synthesize neurotransmitters including the neuropeptide somatostatin. This study was designed to characterize somatostatin receptors both in primary neuroblastoma tumors and in two neuroblastoma cell lines, SKNSH and IMR32. Somatostatin receptors were identified in 6 of 7 Stage I and II compared to 7 of 19 Stage III and IV tumors. Down-regulation of somatostatin receptor binding was observed in five tumors during disease progression. A lack of high affinity binding of somatostatin was identified as a poor prognostic indicator; negative binding correlated with advanced disease and death. Somatostatin receptor binding was observed in the IMR32 cell line, but not in the SKNSH cell line. IMR32 cells demonstrated a single class of high affinity binding sites for both somatostatin and a synthetic analogue, octreotide (Kd 0.16 +/- 0.05 nM and 0.89 +/- 0.23 nM, respectively). Somatostatin and octreotide inhibited both vasoactive intestinal peptide-mediated and forskolin-mediated cyclic AMP accumulation in IMR32 cells. Somatostatin and octreotide inhibition of signal transduction was attenuated by pretreatment of the cells with pertussis toxin. Octreotide inhibited proliferation of IMR32 cells by 70% in a 6-day culture. In contrast, octreotide did not exhibit high affinity binding in SKNSH cells and had no effect on cyclic AMP accumulation or on proliferation in SKNSH cells. Together, these data indicate that octreotide interacts with high affinity somatostatin receptors to modulate signal transduction and regulate proliferation in neuroblastoma cell lines. These data also suggest that somatostatin receptor expression may be an independent prognostic factor in primary neuroblastoma tumors.
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1292
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Muggia FM, Tulpule A, Retzios A, Chen F, Jeffers S, Leichman CG, Leichman L, Spears CP, Chan KK. Intraperitoneal 5-fluoro-2'-deoxyuridine with escalating doses of leucovorin: pharmacology and clinical tolerance. Invest New Drugs 1994; 12:197-206. [PMID: 7896538 DOI: 10.1007/bf00873960] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In a preceding study, we established the tolerance and pharmacokinetic behavior of 5-fluoro-2'-deoxyuridine (FdUrd) given by the intraperitoneal (IP) route. A dose of 3 g daily x 3 days was found satisfactory for Phase II study and exploration of biochemical modulation. Therefore, the current study was conducted to study the tolerance and pharmacokinetics of such a dose-schedule and route of FdUrd combined with escalating doses of leucovorin (LV). Fourteen patients were entered and 13 were evaluable for tolerance determination. Pharmacologic determinations of IP FdUrd and 5-Fluorouracil (FUra) derived from it and LV were obtained by HPLC methods on 11 occasions. Findings were compared with the preceding study of FdUrd alone. LV did not appear to alter the tolerance of IP FdUrd even in the four patients receiving the highest dose of LV (640 mg). Toxicities included nausea, vomiting, and rarely neutropenia and diarrhea. Pharmacokinetic parameters indicate a parallel rate of egress of FdUrd and LV from the peritoneal cavity. The pharmacologic advantage for FdUrd is at least 3 logs as previously reported and one log for LV. Evidence of antitumor effect was noted particularly among untreated patients with gastrointestinal primaries. We conclude that IP FdUrd 3 g and LV in doses of up to 640 mg x 3 days are well tolerated. Since FdUrd is more potent, has an even greater hepatic clearance and shows greater potential for modulation with LV than FUra, it may be the preferred fluoropyrimidine for subsequent studies via the IP route in the treatment of carcinomas with prominent peritoneal spread. The pharmacologic advantage for leucovorin is limited but it is a good marker for peritoneal clearance since it parallels FdUrd clearance.
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1293
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Chen F, Nilsson H, Holmér I. Finger cooling by contact with cold aluminium surfaces--effects of pressure, mass and whole body thermal balance. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY 1994; 69:55-60. [PMID: 7957157 DOI: 10.1007/bf00867928] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Finger skin temperature change during contact with a cold aluminium surface was studied in 20 subjects (10 men and 10 women). Contact pressure (0.1 N, 5.9 N and 9.8 N), contact material mass (large one, mass 3559 g, small one, mass 108 g), surface temperatures (-7 degrees C, 0 degree C, +7 degrees C) and whole body thermal balance were controlled as independent factors. The contact experiments were performed in a small chamber and only the first section of the index finger of the left hand was in contact with the aluminium surface. The results indicated that all the factors studied had significant effects on the contact skin temperature change with time. The study confirmed that a modified Newtonian model with two components can accurately describe the contact skin temperature change with time. The study resulted in three predictive models for critical skin temperature when in contact with cold aluminium. The results indicated that metal surfaces in contact with bare hands should not be below 4 degrees C surface temperature. Lower temperatures require insulating material or the wearing of protective gloves.
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1294
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Ahlgren-Beckendorf JA, Maggio WW, Chen F, Kent TA. Neurofibromatosis 1 mRNA expression in blood vessels. Biochem Biophys Res Commun 1993; 197:1019-24. [PMID: 7505566 DOI: 10.1006/bbrc.1993.2580] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Vascular hypertrophic lesions occur in neurofibromatosis type 1 (NF1). The role of the gene which causes NF1 in the growth and development of blood vessels is not known. mRNA expression of the NF1 gene was studied in blood vessels in the transition between intact and culture and in quiescent and proliferative conditions. The expression and alternative splicing pattern of the catalytic domain of NF1 consistently changed in proliferating cells, supporting a role for this gene in the regulation of growth of vascular smooth muscle and the vascular pathology in NF1.
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MESH Headings
- Animals
- Aorta/cytology
- Aorta/drug effects
- Aorta/metabolism
- Cell Division
- Cells, Cultured
- DNA Primers
- DNA, Complementary/biosynthesis
- DNA, Complementary/metabolism
- Gene Expression/drug effects
- Genes, Neurofibromatosis 1
- Humans
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Neurofibromatosis 1/genetics
- Polymerase Chain Reaction/methods
- RNA, Messenger/biosynthesis
- RNA, Messenger/metabolism
- RNA-Directed DNA Polymerase
- Rats
- Rats, Inbred WKY
- Serotonin/pharmacology
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1295
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Chen F, Huang ZJ, Meng RL, Sun YY, Chu CW. Possible existence of a Van Hove singularity near the Fermi surface of HgBa2CaCu2O6+ delta. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:16047-16050. [PMID: 10008165 DOI: 10.1103/physrevb.48.16047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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1296
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Hayes PM, Liu BH, Knapp SJ, Chen F, Jones B, Blake T, Franckowiak J, Rasmusson D, Sorrells M, Ullrich SE, Wesenberg D, Kleinhofs A. Quantitative trait locus effects and environmental interaction in a sample of North American barley germ plasm. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 1993; 87:392-401. [PMID: 24190268 DOI: 10.1007/bf01184929] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/1993] [Accepted: 03/29/1993] [Indexed: 05/02/2023]
Abstract
Quantitative trait locus (QTL) and QTL x environment (E) interaction effects for agronomic and malting quality traits were measured using a 123-point linkage map and multi-environment phenotype data from an F1-derived doubled haploid population of barley (Hordeum vulgare). The QTL × E interactions were due to differences in magnitude of QTL effects. Highly significant QTL effects were found for all traits at multiple sites in the genome. Yield QTL peaks and support intervals often coincided with plant height and lodging QTL peaks and support intervals. QTL were detected in the vicinity of a previously mapped Mendelian maturity locus and known function probes forα- andβ-amylase genes. The average map density (9.6 cM) should be adequate for molecular marker-assisted selection, particularly since there were few cases of alternative favorable alleles for different traits mapping to the same or adjacent intervals.
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1297
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Chen F, Law SW, O'Malley BW. Identification of two mPPAR related receptors and evidence for the existence of five subfamily members. Biochem Biophys Res Commun 1993; 196:671-7. [PMID: 8240342 DOI: 10.1006/bbrc.1993.2302] [Citation(s) in RCA: 121] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Two additional forms of mouse peroxisome proliferator activated receptor have been identified from cDNA libraries derived from mouse tissues using a low stringency cross-hybridization screening method. One is mNUCI, which has 97% amino acid sequence identity with hNUCI in its DNA binding domain. The other one is mPPAR gamma. The full-length cDNA of mPPAR gamma encodes a protein of 470 amino acids in length. The overall amino acid sequence identity is 75% as compared with xPPAR gamma, with the highest homology in the DNA binding region and ligand binding region, 97% and 86% identity, respectively. The discovery of two new forms of mPPAR and the recent cloning of hPPAR provide evidence for the existence of at least five different forms of receptor in the peroxisome proliferator activated receptor subfamily.
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1298
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Chen F, Ritter JK, Wang MG, McBride OW, Lubet RA, Owens IS. Characterization of a cloned human dihydrotestosterone/androstanediol UDP-glucuronosyltransferase and its comparison to other steroid isoforms. Biochemistry 1993; 32:10648-57. [PMID: 8399210 DOI: 10.1021/bi00091a015] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A human cDNA, UDPGTh-3, encoding a dihydrotestosterone/5 alpha-androstane-3 alpha,17 beta-diol UDP- glucuronosyltransferase (transferase) has been isolated and characterized. The nucleotide sequence of UDPGTh-3 encodes a 530 amino acid protein with a typical membrane insertion-signal peptide, a membrane-anchoring domain, and three potential asparagine-linked glycosylation sites. Alignment shows that this encoded isozyme is 96% identical to an apparent estriol-metabolizing isoform, HLUG4 [Coffman, B. L., et al., (1990) Arch. Biochem. Biophys. 281, 170-175]. The udpgth-3 isozyme is 78% identical to two other steroid isoforms, HLUG25 (udpgth-1) [Jackson, M. R., et al. (1987) Biochem. J. 242, 581-588; Ritter, J. K., et. al. (1992) Biochemistry 31, 3409-3414] and udpgth-2 [Ritter, J. K., et al. (1990) J. Biol. Chem. 265, 7900-7906]. udpgth-2 and udpgth-1 metabolized parallel substrates (stereospecific estriols, 3,4-catechol estrogens, and the bile salt hyodeoxycholate), except that udpgth-2 was 100-fold more effective than udpgth-1. The mRNA encoding udpgth-3 is 2.4 kb in size and is present in liver, prostate, and testis; the mRNA encoding udpgth-2 is located in liver and kidney, whereas that for udpgth-1 is liver-specific. Each of the liver mRNA species encoding udpgth-3, udpgth-2, or udpgth-1 was induced 2.5-3-fold by phenobarbital treatment of the Erythrocebus patas monkey. In 16 human liver mRNA samples, the message encoding udpgth-3 was generally uniformly expressed and that for udpgth-1 exhibited wide variations in its level, whereas that for udpgth-2 was barely detectable in nine samples and not detectable in the others. Three samples contained no message for either isoform. Substrate turnover by udpgth-3 is ranked as follows: phenolphthalein > 5 alpha-androstane-3 alpha,17 beta-diol > 5 alpha- dihydrotestosterone = 4-hydroxybiphenyl > phenolsulfonphthalein (phenol red) > phenolphthalin. Genes encoding udpgth-3, udpgth-2, and udpgth-1 mapped to human chromosome 4 with genomic DNA from human/mouse and human/hamster somatic cell hybrids; the genes encoding udpgth-1 and udpgth-2 mapped specifically to band 4q28. udpgth-3 exhibited similar Km values both for 5 alpha-dihydrotestosterone (10 microM) and for its metabolite, 5 alpha-androstane-3 alpha,-17 beta-diol (12.5 microM).(ABSTRACT TRUNCATED AT 400 WORDS)
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1299
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Wang T, Gu J, Chen F. [Line width addition method and its application to biologic materials emission spectrum analysis]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1993; 24:296-298. [PMID: 8288203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Using alternating current are grating spectrograph, and self-made recording microphotometer for line contour and accurate measurement of line width, we measured the concentration of Cu and Ca in serum-like synthetic standard solution with line width addition method. The experimental results had better linearity, reproducibility and higher precision compared with those by density method, suggesting that line width method is better than density method in the analysis of biologic material concentration.
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1300
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Chu CW, Gao L, Chen F, Huang ZJ, Meng RL, Xue YY. Superconductivity above 150 K in HgBa2Ca2Cu3O8+δ at high pressures. Nature 1993. [DOI: 10.1038/365323a0] [Citation(s) in RCA: 493] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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