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Chen HT, Alexander CB, Mage RG. Characterization of a rabbit germ-line VH gene that is a candidate donor for VH gene conversion in mutant Alicia rabbits. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1995; 154:6365-71. [PMID: 7759874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Normal rabbits preferentially rearrange the 3'-most VH gene, VH1, to encode Igs with VHa allotypes, which constitute the majority of rabbit serum Igs. A gene conversion-like mechanism is employed to diversify the primary Ab repertoire. In mutant Alicia rabbits that derived from a rabbit with VHa2 allotype, the VH1 gene was deleted. Our previous studies showed that the first functional gene (VH4) or VH4-like genes were rearranged in 2- to 8-wk-old homozygous Alicia. The VH1a2-like sequences that were found in splenic mRNA from 6-wk and older Alicia rabbits still had some residues that were typical of VH4. The appearances of sequences resembling that of VH1a2 may have been caused by gene conversions that altered the sequences of the rearranged VH or there may have been rearrangement of upstream VH1a2-like genes later in development. To investigate this further, we constructed a cosmid library and isolated a VH1a2-like gene, VH12-1-6, with a sequence almost identical to VH1a2. This gene had a deleted base in the heptamer of its recombination signal sequence. However, even if this defect diminished or eliminated its ability to rearrange, the a2-like gene could have acted as a donor for gene-conversion-like alteration of rearranged VH genes. Sequence comparisons suggested that this gene or a gene like it could have acted as a donor for gene conversion in mutant Alicia and in normal rabbits.
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Chen HT, Alexander CB, Mage RG. Characterization of a rabbit germ-line VH gene that is a candidate donor for VH gene conversion in mutant Alicia rabbits. THE JOURNAL OF IMMUNOLOGY 1995. [DOI: 10.4049/jimmunol.154.12.6365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Normal rabbits preferentially rearrange the 3'-most VH gene, VH1, to encode Igs with VHa allotypes, which constitute the majority of rabbit serum Igs. A gene conversion-like mechanism is employed to diversify the primary Ab repertoire. In mutant Alicia rabbits that derived from a rabbit with VHa2 allotype, the VH1 gene was deleted. Our previous studies showed that the first functional gene (VH4) or VH4-like genes were rearranged in 2- to 8-wk-old homozygous Alicia. The VH1a2-like sequences that were found in splenic mRNA from 6-wk and older Alicia rabbits still had some residues that were typical of VH4. The appearances of sequences resembling that of VH1a2 may have been caused by gene conversions that altered the sequences of the rearranged VH or there may have been rearrangement of upstream VH1a2-like genes later in development. To investigate this further, we constructed a cosmid library and isolated a VH1a2-like gene, VH12-1-6, with a sequence almost identical to VH1a2. This gene had a deleted base in the heptamer of its recombination signal sequence. However, even if this defect diminished or eliminated its ability to rearrange, the a2-like gene could have acted as a donor for gene-conversion-like alteration of rearranged VH genes. Sequence comparisons suggested that this gene or a gene like it could have acted as a donor for gene conversion in mutant Alicia and in normal rabbits.
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Noheda B, Cereceda N, Iglesias T, Lifante G, Gonzalo JA, Chen HT, Wang YL. Composition dependence of the ferroelectric-paraelectric transition in the mixed system PbZr1-xTixO3. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 51:16388-16391. [PMID: 9978623 DOI: 10.1103/physrevb.51.16388] [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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204
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Nickerson KG, Tao MH, Chen HT, Larrick J, Kabat EA. Human and mouse monoclonal antibodies to blood group A substance, which are nearly identical immunochemically, use radically different primary sequences. J Biol Chem 1995; 270:12457-65. [PMID: 7759488 DOI: 10.1074/jbc.270.21.12457] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A human monoclonal antibody (HuA) specific for blood group A substance with two fucose groups was found to be immunochemically almost identical with that of a previously characterized mouse monoclonal anti-A, AC-1001. The VH and VL chain cDNAs of HuA were sequenced and compared with those of AC-1001. The human and mouse antibodies used VH and Vk genes that came from different families and shared minimal nucleotide and amino acid sequence identity. Thus, two antibodies from two different species can use evolutionarily unrelated sequences to bind the same carbohydrate epitope. The cloned HuA VH and VL genes were then transfected into a mouse myeloma cell line and re-expressed, together, and each separately with an irrelevant VH or VL. Only the original HuA VH and Vk had anti-A activity, demonstrating that both the heavy and light chains contributed to specificity.
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Wu CL, Feng DH, Guidry MW, Chen HT, Pan XW. Single-particle nondegeneracy and SU(3) fermion dynamical symmetry. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1995; 51:R1086-R1089. [PMID: 9970228 DOI: 10.1103/physrevc.51.r1086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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206
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Abstract
Microsurgical replantation has been attempted in the distal phalanx of the digits. Twenty-three complete, single digit amputations are reviewed. The patients' ages ranged from 9 months to 48 years. Viability was 78%. Sensory recovery averaged 7 mm static two-point discrimination. Range of motion in the distal interphalangeal joint of the finger and the interphalangeal joint of the thumb averaged 64 and 51 degrees, respectively. Eight of the 17 successfully replanted digits had mild to moderate atrophy. Eighty-two percent of patients were able to use the replanted digit successfully in their daily work. We feel that distal digital replantation is rewarding. In successful cases, it always preserves acceptable function and good appearance at a price of an average of 2.3 months off work.
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207
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Kashiwada Y, Zhang DC, Chen YP, Cheng CM, Chen HT, Chang HC, Chang JJ, Lee KH. Antitumor agents, 145. Cytotoxic asprellic acids A and C and asprellic acid B. new p-coumaroyl triterpenes, from Ilex asprella. JOURNAL OF NATURAL PRODUCTS 1993; 56:2077-2082. [PMID: 8133297 DOI: 10.1021/np50102a008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Three new p-coumaroyl triterpenes, asprellic acids A [1], B [2], and C [3], were isolated from the EtOH extract of dried leaves of Ilex asprella. The structures for 1-3 have been established as 3,27-di-O-trans-p-coumaroyl [1], 3-O-trans-p-coumaroyl-27-O-cis-p-coumaroyl- [2], and 3-O-cis-p-coumaroyl-27-O-trans-p-coumaroyl- [3] 3 beta,27-dihydroxyolean-12-en-28-oic acid, respectively, by spectral and chemical examinations. Asprellic acid A [1] exhibited potent cytotoxicity against the RPMI-7951 cell line with an ED50 value of 0.62 micrograms/ml, while the cytotoxicity of asprellic acid C [3] against RPMI-7951 was marginal (ED50 5.5 micrograms/ml). Compounds 1 and 3 also showed cytotoxicity against KB cells with ED50 values of 3.75 and 2.86 micrograms/ml, respectively. Asprellic acid B [2] did not show cytotoxicity (> 10 micrograms/ml) against KB or RPMI-7951 cell lines.
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208
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Mowszowicz I, Lee HJ, Chen HT, Mestayer C, Portois MC, Cabrol S, Mauvais-Jarvis P, Chang C. A point mutation in the second zinc finger of the DNA-binding domain of the androgen receptor gene causes complete androgen insensitivity in two siblings with receptor-positive androgen resistance. Mol Endocrinol 1993; 7:861-9. [PMID: 8413310 DOI: 10.1210/mend.7.7.8413310] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We have analyzed the nucleotide sequence of complementary and genomic DNAs of the human androgen receptor (AR) gene in two siblings (patients 9006 and 9030) with receptor-positive complete androgen insensitivity (Rec(+)-CAI). Northern analysis indicated that mRNA of the AR was normal in size. However, its expression was relatively reduced in both patients. Consistent with the normal androgen-binding capacity (496 and 552 fmol/mg DNA for patients 9006 and 9030, respectively) but decreased DNA-binding ability (168 fmol/mg DNA) measured in genital skin fibroblasts, no mutation was found in both N-terminal and ligand-binding domains of the AR. However, a single base substitution (G-->A) was found in the second zinc finger of the DNA-binding domain at nucleotide 2372 of the AR cDNA in both cases. This resulted in the replacement of a highly conserved arginine residue (amino acid 614) by a histidine. When the mutated receptor plasmid was cotransfected into PC-3 cells together with the reporter chloramphenicol acetyltransferase gene, chloramphenicol acetyltransferase activity was not induced by 5 alpha-dihydrotestosterone treatment, confirming that the mutation renders the AR nonfunctional and can, therefore, be held responsible for the clinical features in these patients. These results highlight the importance of Arginine-614 in the second zinc finger of the DNA-binding domain of the AR in the protein-DNA interaction.
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Chen HT, Goh MH, Pan S. The effect and mechanism of the prokinetic action of cisapride on gastrointestinal smooth muscle. GASTROENTEROLOGIA JAPONICA 1993; 28:218-23. [PMID: 8486211 DOI: 10.1007/bf02779223] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cisapride is a new prokinetic agent which can facilitate or restore motility throughout the entire gastrointestinal tract. Although facilitation of acetylcholine release has been suggested, the mechanism of action of cisapride is not clear. To investigate the effect and mechanism of action of cisapride, we used isolated muscle strips (with mucosa and submucosa removed) of guinea pig antrum, ileum and colon to study: (1) the dose response to cisapride, (2) the effect of antagonists (atropine and tetrodotoxin) on the stimulatory effect of cisapride. Besides these studies, we also used 3H-acetylcholine release method to investigate the acetylcholine release effect of cisapride. Cisapride elicited a dose-related enhancement of baseline activity (motility index) on the antrum and contraction on the ileum and colon at the dose of 4, 40 and 400 nM. At higher doses (4 microM) cisapride caused inhibition. This bell-shaped dose response curve suggested that cisapride might be autoinhibitory or that the receptors of cisapride might consist of high affinity stimulatory and low affinity inhibitory sites. The stimulatory responses elicited by cisapride (400 nM) were not significantly inhibited by atropine and tetrodotoxin in the antrum, ileum and colon. This suggested that cisapride might act directly on the smooth muscle. Cisapride (400 nM) evoked a rather small increase of 3H-acetylcholine release on the antrum, ileum and colon. Because the percentage of increase was small and we had demonstrated that the stimulatory effects of cisapride were not blocked by atropine and tetrodotoxin, the acetylcholine release effect of cisapride was considered unimportant.
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Chen HT, Alexander CB, Young-Cooper GO, Mage RG. VH gene expression and regulation in the mutant Alicia rabbit. Rescue of VHa2 allotype expression. THE JOURNAL OF IMMUNOLOGY 1993. [DOI: 10.4049/jimmunol.150.7.2783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Rabbits of the Alicia strain, derived from rabbits expressing the VHa2 allotype, have a mutation in the H chain locus that has a cis effect upon the expression of VHa2 and VHa- genes. A small deletion at the most J-proximal (3') end of the VH locus leads to low expression of all the genes on the entire chromosome in heterozygous ali mutants and altered relative expression of VH genes in homozygotes. To study VH gene expression and regulation, we used the polymerase chain reaction to amplify the VH genes expressed in spleens of young and adult wild-type and mutant Alicia rabbits. The cDNA from reverse transcription of splenic mRNA was amplified and polymerase chain reaction libraries were constructed and screened with oligonucleotides from framework regions 1 and 3, as well as JH. Thirty-three VH-positive clones were sequenced and analyzed. We found that in mutant Alicia rabbits, products of the first functional VH gene (VH4a2), (or VH4a2-like genes) were expressed in 2- to 8-wk-olds. Expression of both the VHx and VHy types of VHa- genes was also elevated but the relative proportions of VHx and VHy, especially VHx, decreased whereas the relative levels of expression of VH4a2 or VH4a2-like genes increased with age. Our results suggest that the appearance of sequences resembling that of the VH1a2, which is deleted in the mutant ali rabbits, could be caused by alterations of the sequences of the rearranged VH4a2 genes by gene conversions and/or rearrangement of upstream VH1a2-like genes later in development.
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211
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Wei FC, Epstein MD, Chen HC, Chuang CC, Chen HT. Microsurgical reconstruction of distal digits following mutilating hand injuries: results in 121 patients. BRITISH JOURNAL OF PLASTIC SURGERY 1993; 46:181-6. [PMID: 8490695 DOI: 10.1016/0007-1226(93)90165-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
From 1982-1989, 152 mutilated distal digits were reconstructed with microsurgical foot tissue transfers in 121 patients. These various foot tissues included wrap-around flaps or pulp from the great toe, second toe, or third toe, as well as partial toe, nail, web space skin, and other portions of the foot. The reconstructions were carried out primarily and secondarily in 78 and 74 patients respectively. The immediate success rate was 98%. Most of the patients were satisfied with both the cosmetic appearance and the functional result. This relatively minor microsurgical foot tissue transfer proved to be an ideal reconstructive option for distal digital defects.
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Chen HT, Alexander CB, Young-Cooper GO, Mage RG. VH gene expression and regulation in the mutant Alicia rabbit. Rescue of VHa2 allotype expression. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1993; 150:2783-93. [PMID: 8454855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Rabbits of the Alicia strain, derived from rabbits expressing the VHa2 allotype, have a mutation in the H chain locus that has a cis effect upon the expression of VHa2 and VHa- genes. A small deletion at the most J-proximal (3') end of the VH locus leads to low expression of all the genes on the entire chromosome in heterozygous ali mutants and altered relative expression of VH genes in homozygotes. To study VH gene expression and regulation, we used the polymerase chain reaction to amplify the VH genes expressed in spleens of young and adult wild-type and mutant Alicia rabbits. The cDNA from reverse transcription of splenic mRNA was amplified and polymerase chain reaction libraries were constructed and screened with oligonucleotides from framework regions 1 and 3, as well as JH. Thirty-three VH-positive clones were sequenced and analyzed. We found that in mutant Alicia rabbits, products of the first functional VH gene (VH4a2), (or VH4a2-like genes) were expressed in 2- to 8-wk-olds. Expression of both the VHx and VHy types of VHa- genes was also elevated but the relative proportions of VHx and VHy, especially VHx, decreased whereas the relative levels of expression of VH4a2 or VH4a2-like genes increased with age. Our results suggest that the appearance of sequences resembling that of the VH1a2, which is deleted in the mutant ali rabbits, could be caused by alterations of the sequences of the rearranged VH4a2 genes by gene conversions and/or rearrangement of upstream VH1a2-like genes later in development.
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213
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Leviton LC, Chen HT, Marsh GM, Talbott EO. Evaluation issues in the Drake Chemical Workers Notification and Health Registry Study. Am J Ind Med 1993; 23:197-204. [PMID: 8422051 DOI: 10.1002/ajim.4700230127] [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: 01/30/2023]
Abstract
The Drake Chemical Workers' Health Registry combined notification of workers about bladder cancer risk with access to a free program for screening and diagnosis. Evaluation of the project has given rise to several findings and new research questions. Findings in this article illustrate the following evaluation issues: 1) studying the combination of strategies that are most effective and cost effective to notify workers of their disease risks, 2) determining the realistic yield from strategies to gain participation in health screening and other protective services for notified workers, 3) identifying the notification strategies that were most effective for different kinds of participants, 4) using process evaluation to identify key activities for ensuring continued participation of cohort members in screening, and 5) examining the extent to which participants are willing to quit smoking to protect their health.
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214
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Chen HT, Feng DH, Wu CL. Optimum pair basis in the nuclear shell model. PHYSICAL REVIEW LETTERS 1992; 69:418-421. [PMID: 10046934 DOI: 10.1103/physrevlett.69.418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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215
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Chen HT, Clark M, Goldman D. Quantitative autoradiography of 3H-paroxetine binding sites in rat brain. J Pharmacol Toxicol Methods 1992; 27:209-16. [PMID: 1421530 DOI: 10.1016/1056-8719(92)90043-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The use of 3H-paroxetine as a ligand for quantitative autoradiography of serotonin (5-HT) transport sites was optimized, and the distribution of 3H-paroxetine binding sites in rat brain was studied. Under the conditions described, 3H-paroxetine binding in forebrain sections was of high affinity and saturable, with a Kd of 0.18 +/- 0.02 nM (mean +/- SEM) and Bmax of 268 +/- 12 fmol/mg of protein (n = 3). Nonspecific binding was 10.7% +/- 1.0 of the total binding (n = 8). The distribution of 3H-paroxetine binding sites closely matched the regional distribution of 5-HT nerve terminals and cell bodies. The highest concentrations of 3H-paroxetine binding sites were found in the dorsal raphe nucleus (563 +/- 55 fmol/mg tissue, n = 4), and high densities of binding were also found in the locus coeruleus, medial forebrain bundle, substantia nigra, several limbic structures (amygdala, hippocampus, hypothalamus, olfactory tubercle, septum, and thalamus), and components of the visual relay system (superior colliculus and the lateral geniculate body). Although lesioning of 5-HT neurons with p-chloroamphetamine (PCA) drastically eliminated 3H-paroxetine binding in most regions of the rat brain, significant binding remained in the raphe nuclei and medial forebrain bundle suggesting that 3H-paroxetine binding in these regions was to presynaptic sites on cell bodies or axons relatively resistant to PCA.
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216
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Chuang DC, Jeng SF, Chen HT, Chen HC, Wei FC. Experience of 73 free groin flaps. BRITISH JOURNAL OF PLASTIC SURGERY 1992; 45:81-5. [PMID: 1562851 DOI: 10.1016/0007-1226(92)90161-p] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The free groin flap has gradually lost its popularity due to the disadvantages relating to the pedicle and the plethora of new donor sites. The purpose of this article is to re-evaluate this time-honoured free flap and to demonstrate its reliability and versatility through a review of 73 free groin flaps performed between 1985 and 1990. 7% of free transfers (total 1096 cases) in our institution were free groin flaps. The complication rate was 8% (three complete failures and three partial failures). This result is acceptable and not so high as other reports have described. The artery discrepancy is the main cause of the complication rate. Two special techniques to gain additional diameter of vessel size to overcome the pedicle disadvantages are stressed. The groin flap has proved to be useful and still deserves consideration in reconstructive procedures.
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217
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Chen HT, Wang XQ. Preparation and combining site characterization of mouse monoclonal anti-B blood group substances. Ann N Y Acad Sci 1991; 636:373-4. [PMID: 1793221 DOI: 10.1111/j.1749-6632.1991.tb33469.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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218
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Wang SS, Tsai YT, Lee SD, Chen HT, Lu CW, Lee FY, Jeng JS, Liu YC, Lo KJ. Spontaneous bacterial peritonitis in patients with hepatitis B-related cirrhosis and hepatocellular carcinoma. Gastroenterology 1991; 101:1656-62. [PMID: 1659549 DOI: 10.1016/0016-5085(91)90405-a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To delineate the natural clinical course of spontaneous bacterial peritonitis in hepatitis B-related cirrhosis and to determine if it occurs in hepatocellular carcinoma, a prospective survey was conducted in 262 patients over 2 1/2 years. The in-hospital incidence and mortality rates of spontaneous bacterial peritonitis were 21.6% and 36.4%, respectively, in cirrhosis and 7.3% and 50% in hepatocellular carcinoma. In cirrhosis, the cumulative probability of annual recurrence of spontaneous bacterial peritonitis was 47.3%, which was significantly higher than the annual probability of occurrence of 11.3% in those with no previous attack (P less than 0.0001). The cumulative probability of annual survival was 27.6% in the spontaneous bacterial peritonitis patients, significantly lower than the probability of 64.0% in the control group (P = 0.0001). A univariate analysis, with Kaplan-Meier curves compared by the Mantel-Cox test, and subsequent multivariate analysis by stepwise Cox regression procedure were used to evaluate 37 variables recorded immediately after admission. Blood urea nitrogen concentration greater than 10.5 mmol/L urea (greater than 30 mg/dL) and ascitic fluid protein concentration less than 7.35 g/L (less than 735 mg/dL) were found to be the only significant predictors of lower annual survival; ascitic fluid protein concentration less than 7.50 g/L (less than 750 mg/dL) was the only significant predictor of higher annual recurrence. The authors conclude that spontaneous bacterial peritonitis has a high risk of recurrence in hepatitis B-related cirrhosis and that the same disease occurring in patients with hepatocellular carcinoma is related to the underlying cirrhosis rather than the hepatocellular carcinoma.
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Abstract
High affinity 3H-paroxetine binding was studied in human frontal cortex and hippocampus obtained from normal controls and alcoholics. On the basis of Scatchard analyses, a significant decrease in the maximal number of binding sites (Bmax) was found in the hippocampus of alcoholics (n = 8) as compared with that of controls (n = 10) (mean +/- SD = 63 +/- 35 vs. 114 +/- 70 fmoles/mg protein). There was no significant difference in the dissociation constants (Kd) between the two groups. The presumed effect of chronic alcohol abuse on 3H-paroxetine binding may be region-specific since no significant difference in either Bmax or Kd for 3H-paroxetine binding was found in the frontal cortex between normal controls and alcoholics. No significant correlation of 3H-paroxetine binding with age or postmortem interval was observed. The decrease in 3H-paroxetine binding in the hippocampus of alcoholics is probably indicative of reduced density of serotonergic nerve terminals either as a preexisting condition or as a result of neuronal damage caused by ethanol or the sequelae of alcoholism, such as nutritional deficiencies.
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Chen HT, Chiou CS, Chang WC. Cloning and characterization of the carp prolactin gene. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1088:315-8. [PMID: 2001405 DOI: 10.1016/0167-4781(91)90071-s] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A carp genomic DNA clone containing the carp prolactin (Prl) gene was isolated with carp Prl cDNA as a probe. The organization of the carp Prl gene was determined by restriction nuclease mapping and nucleotide sequencing. The Prl gene comprises approx. 2.8 kilobasepairs (kb) of DNA including the 5'-flanking region, five exons, four introns and the 3'-flanking region. Analysis of the 5'-flanking region reveals (1) the sequence TATATAAT at positions -38 to -31 upstream from the cap site which was found to be a guanine residue, and (2) the palindrome, CTCATTGCATATACAAATGAG at positions -79 to -59. The carp Prl gene matches with the reported cDNA except for one difference in coding region and five in the 3'-flanking region, while the encoded amino acid sequences are identical. The arrangement of exons and introns is very similar to that seen in carp GH as well as mammalian Prl, which, however, have much longer introns.
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221
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Wang DN, Chen HT, Liao J, Akolkar PN, Sikder SK, Gruezo F, Kabat EA. Two families of monoclonal antibodies to alpha(1----6)dextran, VH19.1.2 and VH9.14.7, show distinct patterns of J kappa and JH minigene usage and amino acid substitutions in CDR3. THE JOURNAL OF IMMUNOLOGY 1990. [DOI: 10.4049/jimmunol.145.9.3002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Nine groove-type mAb to alpha(1----6)dextran were cloned and sequenced. Together with previous reports from this laboratory, the VH and VL of 34 mAb have been sequenced, in which 10 VH19.1.2 and 11 VH9.14.7 combined with the V kappa-Ox1 gene to form two major families of anti-alpha(1----6)dextrans. The same D minigene (DFL16) was used by all VH19.1.2 and VH9.14.7 mAb; however, the patterns of JH and J kappa usage are quite different. VH19.1.2 mAb used only JH3 and J kappa 2, whereas VH9.14.7 mAb used three JH (JH1, JH2, and JH3) and all four active J kappa (J kappa 1, J kappa 2, J kappa 4, and J kappa 5). Relative uniformity in the lengths of VH CDR3 and the junctional sequences is seen in both families. Some mAb from different mouse strains share common structural features. The differences in idiotypic specificities and in the amino acid sequences suggest that VH19.1.2 and VH9.14.7 may differ in the conformation of CDR1 and CDR2. Combining with V kappa-Ox1 gene to generate groove-type combining sites to the single site-filling epitope of alpha(1----6)dextran, the two VH chains may require certain conformations of CDR3. Whether such conformational requirements influence the choice of J minigenes, the selection of the length of VH CDR3 and the sequences at junctions, are discussed.
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Wang DN, Chen HT, Liao J, Akolkar PN, Sikder SK, Gruezo F, Kabat EA. Two families of monoclonal antibodies to alpha(1----6)dextran, VH19.1.2 and VH9.14.7, show distinct patterns of J kappa and JH minigene usage and amino acid substitutions in CDR3. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1990; 145:3002-10. [PMID: 1698868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Nine groove-type mAb to alpha(1----6)dextran were cloned and sequenced. Together with previous reports from this laboratory, the VH and VL of 34 mAb have been sequenced, in which 10 VH19.1.2 and 11 VH9.14.7 combined with the V kappa-Ox1 gene to form two major families of anti-alpha(1----6)dextrans. The same D minigene (DFL16) was used by all VH19.1.2 and VH9.14.7 mAb; however, the patterns of JH and J kappa usage are quite different. VH19.1.2 mAb used only JH3 and J kappa 2, whereas VH9.14.7 mAb used three JH (JH1, JH2, and JH3) and all four active J kappa (J kappa 1, J kappa 2, J kappa 4, and J kappa 5). Relative uniformity in the lengths of VH CDR3 and the junctional sequences is seen in both families. Some mAb from different mouse strains share common structural features. The differences in idiotypic specificities and in the amino acid sequences suggest that VH19.1.2 and VH9.14.7 may differ in the conformation of CDR1 and CDR2. Combining with V kappa-Ox1 gene to generate groove-type combining sites to the single site-filling epitope of alpha(1----6)dextran, the two VH chains may require certain conformations of CDR3. Whether such conformational requirements influence the choice of J minigenes, the selection of the length of VH CDR3 and the sequences at junctions, are discussed.
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Chiou CS, Chen HT, Chang WC. The complete nucleotide sequence of the growth-hormone gene from the common carp (Cyprinus carpio). BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1087:91-4. [PMID: 2400791 DOI: 10.1016/0167-4781(90)90126-m] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have isolated and sequenced a phase clone from a common carp (Cyprinus carpio) genomic library that carries a gene encoding growth hormone (GH). This gene consists of five exons and four introns spanning a region of about 3 kilobase pairs. Its exons correspond with one of two reported cDNAs of carp GH except for nine differences in the nucleotide sequence, while the encoded amino-acid sequences are identical. The sequence upstream from the transcription start point contains two tandem repeats of AACTCTCATG (from -85 to -62) and the typical TATA box. All the introns start with a consensus GT dinucleotide and end with AG. The arrangement of exons and introns is very similar to that seen in mammalian GH, but quite different from the GH genes of rainbow trout and Atlantic salmon.
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Eskay RL, Grino M, Chen HT. Interleukins, signal transduction, and the immune system-mediated stress response. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1990; 274:331-43. [PMID: 2239431 DOI: 10.1007/978-1-4684-5799-5_21] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Overwhelming evidence indicates that the administration of cytokines such as IL-1 alpha and beta, IL-6, and TNF-1 alpha stimulates one or more components of the HPA axis. The hypothesis driving this research is that host infection and tissue injury trigger the synthesis and release of several cytokines that act locally at sites of trauma and distally upon entering the circulation. Available evidence suggests that the primary source of HPA axis-acting or circulating cytokines is activated monocytes or macrophages; therefore, a direct relationship should exist between the appearance of monokines in plasma and the subsequent appearance of pituitary-adrenocortical hormones in plasma as well. Clarification of the physiological role of monokines as mediators of the host stress response will come from in vivo studies in which the type, sequence of appearance, duration of elevation, and quantification of each monokine is monitored along with ACTH and glucocorticoids, following an appropriate immune challenge. In several recent reports, investigators have administered bacterial-derived endotoxin or LPS to stimulate the physiological events associated with infection or injury and chronicled plasma levels of IL-1, IL-6, and TNF-alpha (37,56,57). In human subjects, endotoxin challenge enhanced plasma TNF-alpha levels by 1 hour, which returned to basal levels by 4 hours (37), whereas, IL-6 plasma activity increased at 2 hours post-challenge and returned to baseline by 6 hours (56). Thus, both of these monokines are implicated as possible acute activators of the HPA axis. In perhaps the most revealing study to date, LPS challenge of mice indicated both a differential appearance and disappearance rate in serum for TNF-alpha and IL-1 and a differential regulation of these monokines by glucocorticoid feedback (57). Serum TNF was detected 45 minutes post-LPS, peaked by 1 hour, and returned to control levels by 3 hours. Serum corticosterone concentrations rose rapidly over a time course similar to that of TNF. Even after serum TNF concentration had returned to basal conditions, corticosterone levels remained maximally elevated, and serum corticosterone was still significantly above basal levels 24-hour post-LPS. The rapid return of circulating TNF to pre-LPS challenge levels appeared to be regulated by negative glucocorticoid feedback, because TNF remained maximally elevated for at least 6 hours in adrenalectomized or hypophysectomized mice. LPS-induced levels of IL-1 were delayed as compared to serum TNF, peaked at 4 hours, and remained elevated even at 24 hours.(ABSTRACT TRUNCATED AT 400 WORDS)
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Lee SY, Chou P, Chen HH, Yang IJ, Lin WH, Chen HT. [A community-based study on risk factors of hypertension in Luh-Guu Township]. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1989; 44:235-41. [PMID: 2634458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This is a community-based study on hypertension conducted in 1987 to assess the risk of demographic factors and life style of inhabitants aged over 30 in Luh-Guu Township. One-stage cluster sampling was applied. Through home visit interview, the height, weight, and blood pressure as well as demographic and life style data were taken, and 1171 (57.4%) valid data were completed. Hypertension was defined by American National Heart, Lung, Blood Institute as BP greater than = 140/90mmHg. The prevalence of hypertension was 29.2% (the prevalence was 13.4% if defined by the WHO criteria), and only 27.4% of those hypertensives were self-aware. Univariate analysis found that age, educational level, marital status, job condition, smoking habit, father's hypertension history, and usage of contraceptive were correlated with hypertension. With obesity index in addition to the above 6 factors, except contraceptive usage, as independent variables, the multiple logistic regression analysis showed that, only age and obesity index were significantly correlated with hypertension and the best model were fitted.
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Yang ZL, Wang YZ, Wu CL, Huang YD, Wang QC, Cheng XF, Chen HT. [Toxicity experiment on Sargassum, radix Knoxiae, radix Ransul and flos Genkwa against radix Glycyrrhizae in the antagonism of 18 Chinese drugs]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1989; 14:48-50, 64. [PMID: 2506898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In order to further look into the cause of the antagonisms in the 18 Chinese medicinal herbs, stimulation and toxicity experiments, with five Chinese medicinal herbs (Sargassum Radix Knoxiae, Radix Kansul and Flos Genkwa against Radix Glycyrrhiza) as a group, were done in healthy rats and rabbits.
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Chen HT, Pittman CS. Effect of estrogen on the expression of a cell-surface antigen associated with rat anterior pituitary somatotrophs. Mol Cell Endocrinol 1988; 59:233-40. [PMID: 3053292 DOI: 10.1016/0303-7207(88)90108-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The long-term in vivo effect of diethylstilbestrol (DES) on the expression of a cell-surface antigen associated with the anterior pituitary somatotroph was studied in two strains of female rats using double immunofluorescence techniques. Mab WHC-1, a recently generated and characterized monoclonal antibody, was used to detect the antigen associated with somatotrophs, whereas rabbit anti-rat prolactin (rPRL) and anti-human growth hormone (hGH) antisera were used to identify mammotrophs and somatotrophs, respectively. In F344 rats, Mab WHC-1-positive cells increased from 13.8 +/- 0.5% of total pituitary cells in normal anterior pituitaries to 34.2 +/- 4.0% in DES-induced pituitary tumors. The number of mammotrophs also increased significantly from 58.0 +/- 3.2% in controls to 75.9 +/- 2.2% in tumors. On the other hand, somatotrophs decreased significantly in number following ovariectomy (OVX) and DES implantation (19.7 +/- 0.5% vs. 6.1 +/- 1.2%). Based on double immunofluorescence, the percentage of Mab WHC-1-positive cells, which were somatotrophs, decreased from 85.5 +/- 2.7% in normal controls to 6.7 +/- 1.5% in DES-induced tumors. On the other hand, the percentage of Mab WHC-1-positive cells which were mammotrophs increased significantly from 14.0 +/- 1.4% to 86.1 +/- 1.8% following OVX and DES implantation. A similar change was found in the number of somatotrophs and mammotrophs following the same treatment in Sprague-Dawley (SD) rats which did not develop pituitary tumors. In contrast to F344 rats, the number of Mab WHC-1-positive cells in SD rats decreased significantly from 32.4 +/- 2.8% in sham-operated controls to 19.3 +/- 2.9% in OVX + DES-implanted rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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Louie DS, Chen HT, Owyang C. Inhibition of exocrine pancreatic secretion by opiates is mediated by suppression of cholinergic transmission: characterization of receptor subtypes. J Pharmacol Exp Ther 1988; 246:132-6. [PMID: 2455787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
This study evaluates the hypothesis that opiates suppress pancreatic enzyme secretion by inhibiting cholinergic transmission in the pancreas. Rat pancreatic lobules were incubated in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid-Ringer's buffer and amylase release in response to KCl depolarization of the intrapancreatic nerve in the absence or presence of specific opiate subtype receptor agonists was studied. Depolarization by 75 mM KCl resulted in a 5-fold increase in amylase output. Pretreatment with 1 microM atropine inhibited completely the KCl-stimulated amylase release, suggesting stimulation via a cholinergic pathway. Addition of methionine enkephalin or 2-D-penicillamine-5-D-penicillamine-enkephalin [( D-Pen2, D-Pen5]enkephalin, a specific delta receptor agonist) inhibited KCl-stimulated amylase release in a dose-dependent fashion. Methionine enkephalin (1 microM) or [D-Pen2, D-Pen5]enkephalin inhibited KCl-stimulated amylase release by 32 +/- 4 and 45 +/- 4%, respectively. Addition of 1 microM ICI 174,864 (a delta opiate receptor antagonist) blocked the inhibitory effect of [D-Pen2, D-Pen5]enkephalin. Upjohn 50,488H (1 microM, a specific kappa agonist) and 1 microM Tyr-D-Ala-Gly-MePhe-Gly-ol (a specific mu agonist) had no effect. Methionine enkephalin had no effect on carbachol (1 microM)-stimulated amylase release. These data suggest that methionine enkephalin acts on a delta opiate receptor located on postganglionic cholinergic neurons. To examine the ability of methionine enkephalin to alter acetylcholine release from pancreatic tissue, pancreatic lobules were incubated with [3H]choline and the release of synthesized [3H]acetylcholine was stimulated by KCl. Depolarization of the nerves with 75 mM KCl increased [3H]acetylcholine release by 35 +/- 5% over basal.(ABSTRACT TRUNCATED AT 250 WORDS)
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer
- Acetylcholine/metabolism
- Amylases/metabolism
- Animals
- Cholinergic Fibers/drug effects
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
- Enkephalin, D-Penicillamine (2,5)-
- Enkephalin, Leucine/analogs & derivatives
- Enkephalin, Leucine/pharmacology
- Enkephalin, Methionine/pharmacology
- Enkephalins/pharmacology
- Narcotics/pharmacology
- Pancreas/drug effects
- Pancreas/metabolism
- Pyrrolidines/pharmacology
- Rats
- Rats, Inbred Strains
- Receptors, Opioid/metabolism
- Synaptic Transmission/drug effects
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Abstract
In the present study both the reverse hemolytic plaque assay for detecting luteinizing hormone (LH) secretion from single cells and LH immunocytochemistry (ICC) were applied to conduct quantitative studies on sexual differences in the gonadotrope population during postnatal development. Pituitary glands from both sexes at different ages were monodispersed with 0.1% trypsin. Freshly dispersed cells were incubated in Cunningham chambers in the presence of 10(-7) M gonadotropin-releasing hormone (GnRH) for measurement of the fraction of plaque-forming cells and the mean size of plaque formed, or attached to glass slides for measurement of the fraction of cells staining for LH by ICC. The percentage of immunostained LH cells increased with age in both sexes from about 5% of the total pituitary cell population at 5 days of age to a plateau of about 10% by 15 days and then fell to the adult level of about 5%. There were no significant sexual differences except at 30 and 40 days of age. In female rats the fraction of LH-secreting cells detected by plaque assay matched closely with that of LH-containing cells detected by ICC. However, there were significant sexual differences in the percentage of LH-secreting cells at day 15 through day 40. The mean LH output from individual cells of both sexes as indicated by the mean size of plaques also increased with age and reached a peak around 50 days. The sexual differences were first seen around 30 days of age with greater amounts in the female than in the male.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chen HT, Pan SA. [Mechanism of the acetylcholine-release effect of cisapride on guinea-pig gastrointestinal tract]. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1988; 41:263-70. [PMID: 3179814] [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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231
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Jin ZH, Zhao GL, Ziong SS, Kou PY, Ma LL, Chen HT, Qi JY, Ba QJ, Mai K. An experimental transmission of woodchuck hepatitis virus to young Chinese marmots. Hepatology 1988; 8:371-3. [PMID: 3356418 DOI: 10.1002/hep.1840080230] [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: 01/05/2023]
Abstract
Fourteen young Chinese marmots (Marmota bobak sibirica Radde) were randomly allocated to two groups of seven each. They were injected intrahepatically with a standard woodchuck hepatitis virus challenge pool or a negative pool, prepared from sera of woodchucks with and without woodchuck hepatitis virus infection, respectively. Marmot No. 2 in the experimental group experienced an episode of seroconversion from woodchuck hepatitis surface antigen to anti-woodchuck hepatitis antibody. Woodchuck hepatitis virus DNA was detected, and woodchuck hepatitis surface antigen particles of both spherical and filamentous forms and intact woodchuck hepatitis virus virions were found in its serum. By contrast, none of the control group animals (receiving the negative pool) produced any marker of woodchuck hepatitis virus. This suggests that young Chinese marmots can get woodchuck hepatitis virus infection.
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Chen HT, Pan FM, Chang WC. Purification of duck growth hormone and cloning of the complementary DNA. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 949:247-51. [PMID: 3342241 DOI: 10.1016/0167-4781(88)90089-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Duck growth hormone (GH) was isolated and purified from duck pituitaries by salt precipitation and HPLC on reverse-phase C18 columns. The duck GH was homogeneous as shown by SDS-polyacrylamide gel electrophoresis with a molecular weight of 22,000. The cDNA was synthesized and cloned in Escherichia coli using EcoRI linkers and pBR322 as vector. The positive clones were selected and sequenced. The full-length duck GH cDNA contains 820 nucleotide pairs with an open reading frame coding for the precursor form duck GH of 216 amino-acid residues. The partial amino-acid sequence from the protein completely agrees with that derived from the cDNA, with Phe as the first residue in mature duck GH preceded by a 27-residue hydrophobic signal peptide. The duck GH is almost completely homologous to the chicken GH, with only three conservative substitutions (Ser for Thr, His for Tyr and Lys for Arg) and one deletion (Ala) in the duck GH sequence. Comparison of amino-acid sequence of duck GH with that of various species reveals 56%, 73% and 40% homologies with GHs of human, rat and salmon, respectively.
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233
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Chen HT, Pittman CS. Production and partial characterization of a monoclonal antibody to rat anterior pituitary somatotrophs. Endocrinology 1988; 122:219-26. [PMID: 3275536 DOI: 10.1210/endo-122-1-219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A cell type-specific monoclonal antibody (Mab) against a cell surface antigen of rat anterior pituitary somatotrophs has been generated by fusion of a nonsecreting mouse myeloma line with spleen cells from a mouse immunized with enzymatically dispersed anterior pituitary cells of adult random cycling female rats. Hybridomas were initially screened for antibodies to cell surface antigens by an enzyme-linked immunosorbant assay using rat anterior pituitary cells and smooth muscle cells of aorta as positive and negative controls, respectively. Positive clones were further checked for cell type specificity by immunofluorescence. Mab WHC-1 is an immunoglobulin M (IgM) with kappa-light chains and is cytotoxic in the presence of complement. Based on double immunofluorescence, this Mab reacted with 22.5 +/- 2.0% (+/- SEM) of the anterior pituitary cells of adult random cycling female rats. Among them, about 93.5 +/- 1.4% were somatotrophs, and only 4.1 +/- 1.2% were mammotrophs. Approximately two thirds of the somatotrophs were Mab WHC-1-positive. The reaction of this Mab with gonadotrophs, thyrotrophs, or corticotrophs were negligible. The percentage of Mab WHC-1-positive cells derived from immunoperoxidase staining was significantly greater than that from immunofluorescence. The cell surface antigen defined by Mab WHC-1 is expressed heavily on GH3 cells, but not on smooth muscle cells. It is resistant to trypsin digestion, but sensitive to ethanol treatment, and exhibits the solubility property of a glycolipid. Mab WHC-1 cross-reacts with the anterior pituitary cell of rabbits, but not mice. These results provide the immunological evidence for heterogeneity among somatotrophs and demonstrate the feasibility of making pituitary cell type-specific Mabs.
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Chen HT, Kabat EA, Lundblad A, Ratcliffe RM. Nucleotide and translated amino acid sequences of cDNA coding for the variable regions of the light and heavy chains of mouse hybridoma antibodies to blood group A and B substances. J Biol Chem 1987; 262:13579-83. [PMID: 3115981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
This is the first report of nucleotide and translated amino acid sequences of the variable region light (VL) and heavy (VH) chains of mouse monoclonal hybridoma anti-blood group A and B substances, the combining sites of which have been mapped. Monoclonal hybridoma anti-A and anti-B produced in BALB/c mice by immunization with A or B blood group substances, with A1 erythrocytes, and water-soluble blood group A substance or with synthetic B determinants coupled to bovine serum albumin or to O erythrocytes have been characterized immunochemically. To relate the immunochemical properties of the monoclonals to their primary structures, we have cloned and sequenced cDNAs of variable regions of light and heavy chains of two anti-A and two anti-B. The anti-A hybridomas have very similar combining site specificities and have almost identical VH sequences belonging to the J558 germ-line family, but their VL are from different germ-line VK gene families. The two anti-B hybridomas have different combining site specificities and use the same VL which differs completely from the anti-A VL; their VH are derived from different VH germ-line genes belonging to the J606 family. The results suggest that the heavy chains play a major role in determining the specificities of the antibody combining sites, with only minor contribution of VL. Additional sequence data on monoclonal antibodies of defined specificity for blood group substances are needed for further insights into the genetic and structural basis for their specificities.
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Kyotoku M, Chen HT. Isovector pairing collective motion: Generator-coordinate-method approach. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1987; 36:1144-1156. [PMID: 9954192 DOI: 10.1103/physrevc.36.1144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Chen HT, Makover SD, Kabat EA. Immunochemical studies on monoclonal antibodies to stearyl-isomaltotetraose from C58/J and a C57BL/10 nude mouse. Mol Immunol 1987; 24:333-8. [PMID: 2443831 DOI: 10.1016/0161-5890(87)90174-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Six hybridomas, five from C58/J and one from C57BL/10 nu/nu, immunized with stearyl-isomaltotetraose (S-IM4) were established. One produced IgG3, one IgM and four IgA. The specificities and sizes of the antibody combining sites were determined by quantitative precipitin and ELISA quantitative inhibition assays. All cross-react with alpha(1----6)dextran B512. Their combining sites were complementary to five to seven glucose residues. Association constants of hybridoma antibodies for dextran B512 ranged from 10(3) to 10(5) ml/g, and for isomaltoheptaose (IM7) from 10(3) to 10(4)M-1. Two hybridoma antibodies, one IgA and another IgM derived from different fusions have identical inhibition curves and combining sites, and very close association constants. It will be important to establish whether they have very similar or identical nucleotide sequences in their variable regions. These studies provide further insight into the specificity and repertoire of antidextran combining sites.
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237
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Chen HT. Postnatal development of pituitary lactotropes in the rat measured by reverse hemolytic plaque assay. Endocrinology 1987; 120:247-53. [PMID: 3780561 DOI: 10.1210/endo-120-1-247] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Developmental changes and sexual differences in the lactotrope population were studied with a reverse hemolytic plaque assay for detection and measurement of PRL secretion from individual cells in conjunction with PRL immunocytochemistry (ICC). Pituitary glands from both sexes at different ages were monodispersed with 0.1% trypsin. Freshly dispersed cells were incubated in Cunningham chambers for measurement of the fraction of plaque-forming cells and the size of plaques formed, or attached to glass slides for measurement of the fraction of cells staining for PRL by ICC. The percentage of plaque-forming cells in both sexes gradually increased with age from about 5% of the total anterior pituitary cell population at 5 days of age to the adult levels of about 54% in the females at proestrus and about 37% in the males. Sexual differences in the percentage of plaque-forming cells were consistently seen at 40 days of age and thereafter. The mean size of plaques in both sexes also increased with age from about 1,100 microns 2 at 5 days of age to a peak level of about 15,600 microns 2 in the females at proestrus and about 6,700 microns 2 in the males at 60 days of age; then fell to the adult levels of about 5,500 microns 2 in the females at proestrus and about 3,200 microns 2 in males. Sexual differences first appeared at 40 days of age and were estrogen-dependent. The results from ICC closely matched those from the plaque assay, except at 5 days of age and in the adult males. At 5 days, the fraction of cells staining for PRL was twice that of cells forming plaques. In adult male rats there were about 47% immunostained PRL cells but only about 39% plaque-forming cells. This difference, however, disappeared after estrogen treatment. These results demonstrate that sexual differences in the lactotrope population develop around puberty in rats and appear to be estrogen dependent.
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Abstract
This article describes an experience of successful separation of ischiopagus tripus conjoined twins and their subsequent courses for 76 months.
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Chen HT, Kabat EA. Immunochemical studies on blood groups. The combining site specificities of mouse monoclonal hybridoma anti-A and anti-B. J Biol Chem 1985; 260:13208-17. [PMID: 2414276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mouse monoclonal hybridomas, five anti-blood group A, three anti-B, and one anti-AB, produced by various methods of immunization, have been characterized by quantitative precipitin tests and the fine structures of their combining sites have been mapped by oligosaccharide inhibition assays. The combining sites of antibodies of each specificity differed among themselves. Three of the five monoclonals were specific for difucosyl and two for monofucosyl A determinants. All but the anti-AB were strictly specific for blood group A or blood group B erythrocytes; all of the anti-A monoclonals gave essentially equivalent titers in hemagglutination tests with A1 and A2 erythrocytes except for a monoclonal anti-A prepared by immunization with a human gastric cancer cell line. The data provide additional evidence for the heterogeneity of the antibody response to the different antigenic determinants present on blood A and B substances and emphasize the importance of difucosyl determinants which comprise most of the determinants on the water-soluble blood group substances.
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240
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Chen HT, Kabat EA. Immunochemical studies on blood groups. The combining site specificities of mouse monoclonal hybridoma anti-A and anti-B. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)38857-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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241
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Chen HT, Krmpotic F. Possible hydrogen-like structure for giant resonances in nuclei. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1985; 32:1457-1459. [PMID: 9953001 DOI: 10.1103/physrevc.32.1457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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242
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Chen HT, Roberts JM, Weiner RI. Identification of alpha-adrenergic receptor subtypes in the steer stalk-median eminence. Neuroendocrinology 1984; 38:276-81. [PMID: 6328342 DOI: 10.1159/000123903] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The presence of alpha 1- and alpha 2-receptor subtypes were studied in steer stalk-median eminence (SME) using a selective alpha 1-ligand, [3H]-prazosin, and a selective alpha 2-ligand, [3H]-clonidine. Scatchard analysis of the equilibrium isotherms of specific [3H]-prazosin binding indicated a single class of high affinity (Kd = 0.36 +/- 0.05 nM) and low capacity (Bmax = 111 +/- 19 fmol/mg protein) binding sites, which accounted for approximately 26% of the total sites identified by the non-subtype-selective-alpha-antagonist, dihydroergocryptine ([3H]-DHE). Similarly, computer modeling of the biphasic competition curve of prazosin displacing [3H]-DHE also revealed that there are approximately 26% high affinity sites, presumably alpha 1-, and approximately 74% low affinity sites, presumably alpha 2-receptors in the steer SME. A scatchard plot of specific [3H]-clonidine binding was biphasic and was resolved into a high (Kd = 1.60 +/- 0.34 nM) and low (Kd = 34.5 +/- 7.85 nM) affinity site with the binding capacities of 43 +/- 5 and 200 +/- 37 fmol/mg protein, respectively. The total number of alpha 2-sites identified by [3H]-clonidine accounted for approximately 58% of the total sites labeled by [3H]-DHE, which was in good agreement with that calculated from the competition of clonidine for [3H]-DHE binding (approximately 65% alpha 2 and approximately 35% alpha 1). The rank orders of potency of alpha-adrenergic agents to compete for sites labeled by [3H]-prazosin and [3H]-clonidine were consistent with their labeling alpha 1- and alpha 2-subtypes, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Chen HT, Sylvester PW, Steger RW, Meites J. Effect of adrenalectomy and 5-hydroxytryptophan on phasic release of luteinizing hormone. Life Sci 1984; 34:743-9. [PMID: 6230497 DOI: 10.1016/0024-3205(84)90381-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The effect of 5-hydroxytryptophan (5-HTP) on serum progesterone and the possible role of adrenal progesterone in mediating stimulation by 5-HTP of phasic release of luteinizing. hormone (LH) were investigated in estradiol benzoate (EB)-treated ovariectomized rats. LH surges were induced in long-term (at least two weeks) ovariectomized rats by two injections of EB (20 micrograms/rat, s.c.) with an interval of 72 hrs. Administration of 5-HTP (50 mg/kg, i.p.) at 1000 hr in EB-treated ovariectomized rats resulted in a four-fold increase in serum progesterone within 30 mins, and significantly stimulated the LH surge at 1600 hr. This facilitative effect of 5-HTP on serum LH, but not progesterone, was further potentiated in rats pretreated with P-chlorophenylalanine (PCPA) 72 hrs earlier. Adrenalectomy shortly before 5-HTP administration attenuated the LH surge in saline treated controls, and completely blocked the facilitative effect of 5-HTP on the afternoon surge of LH in rats pretreated with PCPA 72 hrs earlier. On the other hand, chronic adrenalectomy (for 6 days) followed by hydrocortisone (0.2 mg/rat/day) replacement not only had no effect on the LH surge in saline treated controls, but also failed to prevent 5-HTP from facilitating the LH surge in PCPA pretreated rats. On the first day of bleeding, the basal LH value at 1000 hr in sham operated controls was significantly suppressed by PCPA pretreatment 48 hrs earlier. The second dose of 5-HTP administered on the next day failed to potentiate LH surges in either sham operated or adrenalectomized rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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Tsai CL, Chen HT. Total hip replacement. II. Five-year post-operative radiographic study. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1983; 82:757-773. [PMID: 6579226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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245
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Chen HT, Poston JW. Estimates of absorbed energy in trabecular bone due to beta-particles or electrons. HEALTH PHYSICS 1982; 43:647-653. [PMID: 7152926 DOI: 10.1097/00004032-198211000-00002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A computer code, DAB-BE, has been written which can be used to calculate the absorbed energies of beta particles or electrons deposited inside human trabecular bone. The radiation source geometry can be either uniformly distributed in the whole bone or located at a fixed point inside the bone. Bremsstrahlung effects are not considered in these calculations. Results are presented and discussed for six monoenergetic sources of electrons distributed uniformly in a mathematical representation of the arm. In addition, a fixed point source configuration of 1.0 MeV monoenergetic electrons was studied.
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Chen HT, Roberts JM, Weiner RI. Binding of [3H]dihydroergocryptine to an alpha-adrenergic site in the stalk median eminence of the steer. Endocrinology 1981; 109:2138-43. [PMID: 6273131 DOI: 10.1210/endo-109-6-2138] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Dihydroergocryptine (DHE), a potent dopamine agonist and alpha-adrenergic antagonist, has been used as a radioligand to characterize both dopamine and alpha-adrenergic receptors. In the present study, the binding of [3H]DHE to particulate fractions of the steer stalk median eminence was characterized using a filtration assay. Specific binding was defined by the presence of 10 microM phentolamine or by an iterative nonlinear hyperbolic curve-fitting program. Scatchard analysis of equilibrium isotherms of specific binding defined a single high affinity (Kd = 1.78 +/- 0.22 nM), saturable (maximum binding, 481 +/- 39 fmol/mg protein), stereoselective binding site. The Kd, calculated from the ratio of the rate constants k2 and k1, was 2.8 +/- 0.14 nM. The rank order of potency of agonists to compete for [3H]DHE binding (l-epinephrine greater than l-norepinephrine greater than dopamine greater than l-isoproterenol) was consistent with interactions at an alpha-adrenergic site. The rank order of potency of alpha-antagonists (phentolamine greater than yohimbine greater than prazosin) suggested that this was an alpha 2-adrenergic receptor. The affinity of dopamine agonists for the [3H]DHE-binding site was 10-fold lower relative to their potency at known dopamine receptors, while the affinity of dopaminergic antagonists was 100-fold lower. Furthermore, Scatchard analysis of specific [3H]DHE binding in the presence of a concentration of spiperone which should saturate dopamine receptors, only decreased the number of binding sites by 9%. These data demonstrate the presence of large numbers of alpha-adrenergic receptors in the stalk median eminence of the steer. Only a small number of dopaminergic binding sites for [3H]DHE appeared to be present.
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Chen HT, Sylvester PW, Ieiri T, Meites J. Potentiation of luteinizing hormone release by serotonin agonists in ovariectomized steroid-primed rats. Endocrinology 1981; 108:948-52. [PMID: 6450677 DOI: 10.1210/endo-108-3-948] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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248
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Shih JS, Chen HT, Liu HC. Interim follow-up studies of innominate osteotomy for congenital dislocation of the hip. Clin Orthop Relat Res 1980:261-5. [PMID: 7438612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Innominate osteotomy alone without any adjunctive procedures was performed for congenital dislocation of the hip in 30 children. A complete follow-up study of an average of four years and nine months was obtained for 20 hips in patients. These interim results were quite gratifying. Clinical and radiologic assessments by a score system of Trevor and associates revealed that 85% of the hips that had been operated upon were functionally satisfactory. There were three cases of redislocation which were classified as resulting from technical failures.
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Leung FC, Chen HT, Verkaik SJ, Steger RW, Peluso JJ, Campbell GA, Meites J. Mechanism(s) by which adrenalectomy and corticosterone influence prolactin release in the rat. J Endocrinol 1980; 87:131-40. [PMID: 7430912 DOI: 10.1677/joe.0.0870131] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The possible direct effect of corticosterone on release of pituitary prolactin was examined in a system using incubation for 8 h. Corticosterone at either 0·1 or 1 μg/ml medium had no significant effect on in-vitro prolactin release but 10 or 100 μg/ml medium produced a significant inhibition of release of prolactin. Release of LH, FSH and thyroid-stimulating hormone were not altered by 0·1, 1 or 10 μg corticosterone/ml, indicating that its action at the concentration of 10 μg/ml was specific on release of prolactin. Corticosterone injected at doses of 1 or 5 mg/kg into hypophysectomized rats with two pituitary grafts underneath the kidney capsule produced a significant fall in serum levels of prolactin when compared with control hypophysectomized rats with two pituitary grafts. Examination with the electron microscope showed that about one third of the lactotrophes from adrenalectomized rats after corticosterone injection exhibited patterns which suggested a decrease in protein synthesis when compared with lactotrophes from adrenalectomized rats given only the vehicle injection. These observations indicated that inhibition of release of prolactin by corticosterone could be exerted directly on the pituitary gland, and that the rise of serum levels of prolactin after adrenalectomy might have been due to the removal of direct inhibition by corticosterone.
Male rats were adrenalectomized and 2–3 weeks later, concentrations of dopamine and noradrenaline in the medial basal hypothalamus were measured and found not to be different from values in intact rats. Dopamine metabolism also was not altered in the median eminence. The dopaminergic agonist, l-DOPA, inhibited, and the antagonists, pimozide and haloperidol, stimulated release of prolactin in both adrenalectomized and intact rats. Serotonin (5-HT) metabolism in the medial basal hypothalamus and anterior hypothalamus of adrenalectomized rats was not significantly different from values in intact rats, but a higher concentration of 5-HT was observed in the medial basal hypothalamus of adrenalectomized rats when compared with the values in intact rats. A serotonergic agonist, fluoxetine, and an antagonist, cyproheptadine, had no apparent effect on release of prolactin in intact rats, but fluoxetine produced a significant rise, and cyproheptadine, a significant lowering of serum levels of prolactin in adrenalectomized rats. These results suggest that 5-HT, but not dopamine, may be involved in the rise of prolactin after adrenalectomy.
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Tsai CL, Chen HT. Total hip replacement. I. Preliminary report of 105 patients with particular reference to underlying disease process. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1980; 79:774-789. [PMID: 6939791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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