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Tong Y, Somjen G, Teeuwsen W, Royle JP. Percutaneous transluminal angioplasty: follow-up with treadmill exercise testing. CARDIOVASCULAR SURGERY (LONDON, ENGLAND) 1994; 2:503-7. [PMID: 7953458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Between 1986 and 1992, 308 percutaneous transluminal angioplasties in 252 patients were reviewed in the vascular laboratory of the Austin Hospital. The follow-up period ranged from 1 month to 6 years. Treadmill exercise testing was used as an additional mode of assessment to resting ankle/brachial pressure indices in monitoring outcome. Early haemodynamic improvement rate was 86.7%. In 267 successful cases, 199 had increased the mean(s.d.) resting ankle/brachial pressure index from 0.68(0.15) to 0.96(0.14) (P < 0.05) and another 68 with normal or unchanged resting ankle/brachial pressure indices after the procedure increased the mean(s.d.) post-exercise pressure index from 0.45(0.24) to 0.82(0.23) (P < 0.05). The primary haemodynamic improvement rate of initially successful percutaneous transluminal angioplasties was 80.1% at 1 year and was maintained in 46.1% of cases 5 years after. Treadmill exercise testing revealed reduction of the ankle/brachial pressure index in 69 patients during follow-up, indicating restenosis of the dilated lesion or development of a new arterial stenosis. Fifty-two of the 69 patients exhibited a significant drop in the resting pressure index. However, in the 17 remaining patients, only the post-exercise index decrease indicated haemodynamic deterioration. Treadmill exercise testing proved to be valuable adjunct in detecting haemodynamic changes after percutaneous transluminal angioplasty.
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Ross DD, Wooten PJ, Tong Y, Cornblatt B, Levy C, Sridhara R, Lee EJ, Schiffer CA. Synergistic reversal of multidrug-resistance phenotype in acute myeloid leukemia cells by cyclosporin A and cremophor EL. Blood 1994; 83:1337-47. [PMID: 8118035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Cremophor (Crem) EL, the vehicle for intravenous delivery of cyclosporin A (CsA), has been reported to counteract multidrug resistance (MDR) in P-glycoprotein (Pgp)-over-expressing cell lines. Because of this, we sought to determine whether Crem functions independently as a modulator of MDR in blast cells obtained from acute myelogenous leukemia (AML) patients, and the nature of its interaction in combination with CsA in reversing an MDR phenotype. In the phenotypically classical MDR AML cell lines HL-60/Vinc (overexpresses Pgp) or HL-60/AR (does not overexpress Pgp), the dose causing half-maximum enhancement (D50) of daunorubicin (DNR, 1 micrograms/mL, 3 hours) accumulation was achieved by the combination of CsA and Crem (CsA/Crem) at 1.2 mumol/L CsA. In contrast, the D50 for Crem alone was approached at an amount that would be needed to suspend 6.2 mumol/L CsA for HL-60/Vinc, and 81 mumol/L CsA for HL-60/AR. The D50 concentrations for CsA alone (dissolved in ethanol, which does not alter DNR accumulation) were also higher than those for CsA/Crem, being 6.5 mumol/L for HL-60/Vinc, and 3.1 mumol/L for HL-60/AR. The maximum absolute level of enhancement of DNR accumulation (Emax) in each cell line was approximately equivalent for CsA/Crem or CsA alone, and was equal to the 3 hr intracellular DNR accumulation observed in parental, drug sensitive HL-60/W cells. For Crem alone, HL-60/AR and HL-60/Vinc cells showed markedly different responses: HL-60/Vinc cells attained intracellular DNR content comparable to HL-60/W, whereas HL-60/AR cells achieved only approximately 35% of this level. Multiple-drug effects were analyzed by calculation of the Combination Index (Chou and Talalay, Adv Enzyme Regul 22:27, 1984), which indicated that CsA and Crem are synergistic in causing enhancement of DNR accumulation in these MDR HL-60 cell lines. In blasts from AML patients, 5 mumol/L CsA/Crem or an equivalent amount of Crem alone each caused significant (P < .001) enhancement of DNR accumulation (60 AML-patient marrow samples) or DNR retention (51 AML-patient marrows). Similarly, CsA/Crem or Crem alone caused significant (P < .01) enhancement of the cytotoxicity of DNR in 36 AML blast cell specimens. The degree of enhancement of accumulation/retention or cytotoxicity by CsA/Crem was approximately equivalent to that obtained with Crem alone. These studies indicate that Crem can reverse an MDR phenotype in patient AML blast cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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Bongue-Bartelsman M, O'Neill SD, Tong Y, Yoder JI. Characterization of the gene encoding dihydroflavonol 4-reductase in tomato. Gene 1994; 138:153-7. [PMID: 7907304 DOI: 10.1016/0378-1119(94)90799-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A cDNA clone (DFR) encoding dihydroflavonol 4-reductase was identified from tomato hypocotyls. Nucleotide and amino acid sequence comparisons to Petunia hybrida, Antirrhinum majus and Zea mays DFR sequences confirmed that the cDNA encodes the structural DFR gene. In tomato, the DFR sequence appeared to be present as a single gene and mapped to a region on chromosome 2 near two loci affecting anthocyanin pigmentation, are and aw. DFR was expressed in both leaf and hypocotyl tissue. Sequencing data from two DFR cDNA clones indicated there are alternative polyadenylation sites on DFR.
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Somjen GM, Royle JP, Tong Y, MacLellan DG. Duplex scanning and light reflection rheography in the assessment of the severity of short saphenous vein incompetence. THE JOURNAL OF DERMATOLOGIC SURGERY AND ONCOLOGY 1993; 19:635-8. [PMID: 8349901 DOI: 10.1111/j.1524-4725.1993.tb00403.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Duplex ultrasound assessment of veins in the popliteal fossa is an accepted alternative to venography. Light reflection rheography provides additional quantitative information on venous reflux in chronic venous insufficiency. OBJECTIVE To use duplex ultrasound and light reflection rheography to study the venous reflux patterns in the popliteal fossa in a group of patients. METHODS Duplex ultrasound examination and light reflection rheography were used in the assessment of the severity of short saphenous vein incompetence. RESULTS The study revealed that any associated deep venous reflux which was detectable beyond the saphenopopliteal junction represented a more advanced stage of superficial venous insufficiency. CONCLUSIONS Light reflection rheography, as a semiquantitative test, provided useful additional information to duplex scan findings in assessing venous reflux of the popliteal fossa. Short saphenous vein reflux with functional deep venous incompetence was associated with shorter venous refilling times and clinically represented a more advanced stage of primary varicose vein disease.
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Tong Y, Tucker SB. Normal human skin lymphocytic and Langerhans' cell responses to intradermal interferon alpha-2 beta injections. Am J Med Sci 1993; 306:23-7. [PMID: 7687094 DOI: 10.1097/00000441-199307000-00007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of intradermal injection of interferon alpha-2 beta on normal human skin were studied in 12 healthy adult volunteers using 500,000 international units recombinant human interferon alpha-2 beta, 3 times a week for five injections (n = 6) and nine injections (n = 6). Saline injections served as control sites. Lymphocytic infiltrates and the population of epidermal Langerhans' cells in the injection areas were observed. The results showed that epidermal Langerhans' cells (both adenosine triphosphatase positive and CD-1+) decreased significantly whereas human leukocyte antigen-DR expression in keratinocytes was enhanced. Dermal CD-3+ (Pan T cells), CD-4+ (T helper cells) and human leukocyte antigen DR+ cells increased. No significant differences in the number of CD-19+ (B cells) and CD-57+ (NK cells) were observed. There were no significant differences between the five-injection and nine-injection groups.
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Yin J, Harpaz N, Tong Y, Huang Y, Laurin J, Greenwald BD, Hontanosas M, Newkirk C, Meltzer SJ. p53 point mutations in dysplastic and cancerous ulcerative colitis lesions. Gastroenterology 1993; 104:1633-9. [PMID: 8500720 DOI: 10.1016/0016-5085(93)90639-t] [Citation(s) in RCA: 165] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The molecular basis of colorectal dysplasia and carcinoma arising in ulcerative colitis is poorly understood. Loss of heterozygosity involving the tumor suppressor gene p53 occurs frequently in neoplastic ulcerative colitis lesions. Point mutation affecting p53 is associated with loss of heterozygosity in other cancers. Therefore, it was determined whether p53 point mutation occurs in ulcerative colitis-associated neoplasia. METHODS Single-strand conformation polymorphism analysis, DNA sequencing, and loss of heterozygosity studies were performed on 45 patients with ulcerative colitis-associated dysplasia and carcinoma. RESULTS Point mutations were detected in 26 lesions from 20 patients, including 18 carcinomas, 6 dysplasia-associated masses, 1 flat dysplasia, and 1 lymph node metastasis. In two cases, identical p53 mutations were observed in both carcinoma and adjacent dysplasia. Missense mutations causing amino acid substitutions as well as nonsense mutations resulting in premature stop codons were seen. Tandem mutations, in which more than 1 sequence alteration occurred on the same allele of p53, were also detected. Point mutation was accompanied by loss of the other p53 allele in 8 of 10 patients informative for both loss of heterozygosity and mutation assays. CONCLUSIONS These findings suggest that inactivation of p53 by mutation and loss of heterozygosity is a common mechanism of malignant transformation in ulcerative colitis. They also imply that in contrast to sporadic colorectal carcinoma, ulcerative colitis-associated neoplastic progression may involve p53 inactivation at relatively early, noninvasive stages.
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Huang Y, Meltzer SJ, Yin J, Tong Y, Chang EH, Srivastava S, McDaniel T, Boynton RF, Zou ZQ. Altered messenger RNA and unique mutational profiles of p53 and Rb in human esophageal carcinomas. Cancer Res 1993; 53:1889-94. [PMID: 8467510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Seventy-nine esophageal carcinoma patients were studied for genetic abnormalities in the p53 and Rb tumor suppressor genes. Single-strand conformation polymorphism analysis and DNA sequencing were used to detect p53 point mutations, Northern blotting was used to examine abnormal expression of p53 and Rb, and polymerase chain reaction and Southern blotting were used to analyze allelic loss. Twenty-five cases were analyzed by DNA sequencing to detect mutations in p53. Fourteen samples contained mutations within exons 5 through 9 of p53; seven had missense mutations giving rise to single amino acid substitutions. The remaining seven (50%) contained nonsense mutations leading to premature termination, five due to single base pair substitutions, and two that were the result of frameshift mutations. In other human tumors, p53 mutations are predominantly missense mutations, but our data as well as those from other groups show that nonsense mutations are common in human esophageal cancer. All but one of the constitutionally heterozygous samples containing mutations also manifested loss of the normal p53 allele; the one exception without allelic loss contained a silent mutation, which should not have had any affect on the p53 protein product. In addition, Northern blotting analysis revealed abnormalities (altered transcript size or mRNA levels) in 5 of 7 cases involving p53 and in 2 of 7 cases analyzed for Rb. Thirty-four cases were informative for allelic loss studies of both p53 and Rb; of these, 25 (74%) lost heterozygosity of p53, Rb, or both. When point mutations and mRNA expression abnormalities were also considered, 33 of 45 (73%) tumors informative for allelic loss assays of both genes as well as for mRNA or point mutation studies showed one or more abnormalities in p53 or Rb. Our results strongly suggest that a unique profile of molecular alterations involving p53 and Rb characterizes human esophageal cancer and that these specific genetic lesions are important in the development and/or progression of most human esophageal carcinomas.
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Tong Y. [An observation of the effects of rat's condylar cartilage after application of retractive force on the mandible]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1993; 28:41-3, 64. [PMID: 8222949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The changes of histologic structure and matrix secreting of rat's condylar cartilage after application of upward retractive force to the mandible were investigated by means of histology and histochemistry. After the force application, the condylar cartilage became thinner, the amount of the cells in the germ zone decreased, and that in the transition and transform zone were extremely or even disappeared. Sometimes a calcification zone was discovered in the cartilage and some cells of the mature zone were embed in it. The amount of acid mucopolysaccharide in the matrix also decreased. The result indicated that the retractive force inhibited the proliferation and differentiation of condylar cartilage remarkedly. This was the mainly morphologic bases of the shorted mandible which as a result of the retractive force applied to the mandible.
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Huang Y, Boynton RF, Blount PL, Silverstein RJ, Yin J, Tong Y, McDaniel TK, Newkirk C, Resau JH, Sridhara R, Reid BJ, Meltzer SJ. Loss of heterozygosity involves multiple tumor suppressor genes in human esophageal cancers. Cancer Res 1992; 52:6525-30. [PMID: 1423299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Loss of heterozygosity occurring on various chromosomes has been described in the majority of human tumors. The targets of frequent or consistent subchromosomal deletions are believed to be tumor suppressor genes. We examined 72 esophageal tumors (46 squamous cell carcinomas and 26 adenocarcinomas) for loss of heterozygosity at the p53, Rb, APC, MCC, and DCC loci. Inclusion of these tumor suppressor genes in the allelic deletions was directly ascertained by performing polymerase chain reaction at polymorphic sites within the genes. Loss of heterozygosity occurred in 55% of informative cases at p53, in 48% of informative cases at Rb, in 66% at APC, in 63% at MCC, and in 24% at DCC. Ninety-three % of tumors informative at all loci (fully informative) lost heterozygosity of at least one locus. A high percentage of fully informative tumors (71%) also lost heterozygosity at more than one locus. There were no significant differences among histological types in the prevalence of loss of heterozygosity at any locus. There were correlations of losses involving MCC versus DCC, Rb, and p53. These data suggest that (a) allelic deletions including these tumor suppressor genes are important in the formation and/or progression of most esophageal cancers; (b) allelic deletions involving MCC may not occur independently of deletions involving other tumor suppressor genes; and (c) the accumulation of multiple allelic deletions involving specific tumor suppressor genes may be important in most esophageal tumorigenesis or tumor evolution.
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Tong Y, Pelletier G. Prolactin regulation of pro-opiomelanocortin gene expression in the arcuate nucleus of the rat hypothalamus. Neuroendocrinology 1992; 56:561-5. [PMID: 1475014 DOI: 10.1159/000126274] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
It is well known that the opiate peptides, especially the pro-opiomelanocortin (POMC)-related peptide beta-endorphin, stimulate the release of prolactin (PRL) in the rat. In order to evaluate the involvement of PRL on the activity of POMC neurons in the arcuate nucleus, we have studied the effects of the injection of PRL into the third ventricle of intact and hypophysectomized rats as well as the effects of hyperprolactinemia induced by pituitary implants under the kidney capsule on POMC gene expression. The amounts of POMC mRNA in the arcuate nucleus were measured by in situ hybridization using a [35S]-labelled cDNA probe encoding for POMC. Hypophysectomy performed 2 weeks previously decreased by 24% the number of silver grains/unit of surface of labelled neurons. Intracerebroventricular injection of 3 micrograms of PRL 4 h before sacrifice induced a significant decrease in the hybridization signal of 32 and 20% in the intact and hypophysectomized rat, respectively. Hyperprolactinemia achieved by pituitary implants also led to a significant decrease in POMC mRNA levels. The present data show that hypophysectomy depresses hypothalamic POMC mRNA levels and that this effect is not related to the suppression of PRL secretion since this hormone exerts an inhibitory action on POMC gene expression. They suggest that the regulation of PRL secretion by short loop feedback mechanism might be well mediated by beta-endorphin which has already been shown to inhibit dopaminergic neuron activity in the arcuate nucleus.
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Tong Y, Pelletier G. Role of dopamine in the regulation of proopiomelanocortin (POMC) mRNA levels in the arcuate nucleus and pituitary gland of the female rat as studied by in situ hybridization. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1992; 15:27-32. [PMID: 1331668 DOI: 10.1016/0169-328x(92)90147-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The effects of the dopaminergic antagonist haloperidol (HAL) as well as the D2 dopamine receptor agonist bromocriptine (BRO) on proopiomelanocortin (POMC) mRNA levels in the female rat arcuate nucleus and pituitary were investigated by quantitative in situ hybridization. Since we had already shown that sex steroids could induce a decrease in POMC mRNA levels in the arcuate nucleus of castrated rats, the involvement of the dopaminergic system in the inhibitory effect of estradiol (E2) was also investigated. In situ hybridization was performed on paraformaldehyde-fixed cryostat sections through the arcuate nucleus and whole pituitary gland using a 35S-labelled cDNA probe encoding for POMC. In the arcuate nucleus of intact animals, a 14-day treatment with BRO increased by 54% the number of silver grains/unit of surface of labelled neurons while HAL decreased by 30% the value of this parameter. Hypophysectomy which induced a 20% decrease in the hybridization signal could not prevent the effects of BRO or HAL. Ovariectomy performed 14 days earlier increased by 20% the number of silver grains while a 14-day treatment of ovariectomized animals with E2 decreased the hybridization signal by 32%. On the other hand, the concomitant administration of HAL and E2 did not induce significant variations in POMC mRNA levels compared to those obtained following HAL administration, but slightly decreased the hybridization signal by 20% compared to that induced by E2 alone. In the intermediate lobe of the pituitary, BRO markedly depressed (30% of control values) and HAL increased by 50% the levels of POMC mRNA. The present data clearly demonstrate that POMC mRNA levels are differently regulated by dopamine in the intermediate lobe of the pituitary and the arcuate nucleus and that the effects of BRO and HAL on arcuate POMC mRNA are not mediated by the pituitary gland. They do not allow to draw any definite conclusion about the possible involvement of the dopaminergic system in the inhibitory role of E2 on POMC gene regulation.
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Wu L, Tong Y, Mao S, Cheng L, Wang X. [Anti-inflammatory effect of differently processed rhizoma Typhon] off. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:339-42, 382. [PMID: 1418576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Rat was employed to study the anti-inflammatory effect of Rhizoma Typhon processed by different methods. The result showed that processed and raw Rhizoma Typhon had similar action. With the new processing method similar anti-inflammatory effect was obtained compared with the old processing method.
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Tong Y, Veilleux R, Pelletier G. Regulation of Prolactin Messenger Ribonucleic Acid Levels by Estradiol and Dihydrotestosterone as Evaluated by in situ Hybridization Performed on Implanted Pituitary Glands and Anterior Pituitary Cells in Culture in the Male Rat. J Neuroendocrinol 1992; 4:359-110. [PMID: 21554618 DOI: 10.1111/j.1365-2826.1992.tb00180.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have recently demonstrated that 17ß-estradiol (E(2) ) administration increases protactin (PRL) mRNA levels in the male rat anterior pituitary gland and that this stimulatory effect is partially inhibited by concomitant administration of dihydrotestosterone. In order to gain more information about the site(s) of action of E(2) and dihydrotestosterone on PRL gene expression, we have studied the effects of these two hormones in pituitaries implanted under the kidney capsule as well as in anterior pituitary cells in culture. In implanted pituitaries, PRL mRNA levels were increased by 90% as compared to values obtained in the stalk-connected pituitaries from the same animals. Administration of E(2) induced a further increase of PRL mRNA levels in implanted pituitaries, while dihydrotestosterone did not produce any change in animals which had been treated or not with E(2) . In anterior pituitary cells in culture, addition of E(2) to the culture medium resulted in a 60% increase of PRL mRNA levels over control values. Supplementation with dihydrotestosterone did not induce any variation in the concentration of PRL mRNA in cells which were treated or not with E(2) . These results indicate that E(2) exerts a direct action on PRL cells at the pituitary level and strongly support the key role of the hypothalamus in the inhibitory effect of androgens on estrogen-induced stimulation of PRL mRNA in the male rat pituitary.
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Boynton RF, Blount PL, Yin J, Brown VL, Huang Y, Tong Y, McDaniel T, Newkirk C, Resau JH, Raskind WH, Haggitt RC, Reid BJ, Meltzer SJ. Loss of heterozygosity involving the APC and MCC genetic loci occurs in the majority of human esophageal cancers. Proc Natl Acad Sci U S A 1992; 89:3385-8. [PMID: 1565631 PMCID: PMC48872 DOI: 10.1073/pnas.89.8.3385] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The tumor suppressor gene APC was recently identified, and the cDNA was cloned from chromosome 5q21. Point mutations affecting APC are seen in the hereditary syndrome familial adenomatous polyposis, and point mutations in APC and a closely linked gene, MCC, as well as loss of heterozygosity involving chromosome 5q have been reported in sporadic colon cancer. To our knowledge, loss of heterozygosity involving APC or MCC or both has not yet been described in any other human cancer besides lung cancer. We used the polymerase chain reaction and DNA content flow cytometric nuclear sorting to examine 30 primary human esophageal cancers for loss of heterozygosity of APC or MCC or both. Loss of one allele was detected in 77% of 26 informative cases. These data suggest that loss of heterozygosity of regions on 5q including the APC and MCC genetic loci is involved in the development and/or progression of most human esophageal cancers. They imply that inactivation of APC, MCC, and/or a linked gene on chromosome 5q plays a role in the pathogenesis of some cancers of the upper gastrointestinal tract, as well as in colon cancer and familial adenomatous polyposis.
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Greenwald BD, Harpaz N, Yin J, Huang Y, Tong Y, Brown VL, McDaniel T, Newkirk C, Resau JH, Meltzer SJ. Loss of heterozygosity affecting the p53, Rb, and mcc/apc tumor suppressor gene loci in dysplastic and cancerous ulcerative colitis. Cancer Res 1992; 52:741-5. [PMID: 1346256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Allelic deletions of tumor suppressor genes have been observed frequently in a variety of human tumors. These losses are believed to contribute to the development of human cancer. Three of the most frequently deleted chromosomal loci contain the tumor suppressor genes p53, retinoblastoma (Rb), and mcc/apc. In order to detect loss of heterozygosity (LOH) within these genes in dysplastic and cancerous ulcerative colitis, we used an application of the polymerase chain reaction. LOH affecting p53 was observed in 8 of 17 (47%) of heterozygous patients, while LOH of Rb and the mcc/apc locus was observed in 9 of 27 (33%) and 13 of 39 (33%) of heterozygotes, respectively. Among 35 patients heterozygous at 2 or more loci, LOH of p53, Rb, and/or mcc/apc was observed in 18 (51%). LOH was more common in left-sided neoplasms. These data suggest that allelic deletion of p53, Rb, mcc, and/or apc is involved in the pathogenesis and/or progression of at least a subset of colonic dysplasias and carcinomas occurring in the setting of ulcerative colitis.
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Somjen GM, Royle JP, Fell G, Roberts AK, Hoare MC, Tong Y. Venous reflux patterns in the popliteal fossa. THE JOURNAL OF CARDIOVASCULAR SURGERY 1992; 33:85-91. [PMID: 1545004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Incompetent veins in the popliteal fossa were assessed with duplex ultrasound in 123 legs of 104 patients. In 91 cases the venous reflux was the result of a single incompetent vein draining into the deep system. In 32 cases duplex ultrasound demonstrated a combination of incompetent veins. With the exception of 3 patients duplex scanning accurately localised the incompetent veins and their "junctions" with the deep system. In 48 legs the reflux signal, detected in the surface vein, extended back beyond the "junction" into a proximal segment of the popliteal vein or superficial femoral vein; in most cases the distal popliteal vein remained competent. Six distinct venous reflux patterns were identified in the popliteal fossa, which seemed to correlate with the severity of related clinical symptoms.
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Tong Y, Pelletier G. In vivo Regulation of Prolactin Gene Expression in the Male Rat: Role of Sex Steroids and Dopamine. J Neuroendocrinol 1991; 3:635-9. [PMID: 19215533 DOI: 10.1111/j.1365-2826.1991.tb00328.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract The influence of sex steroids and the dopaminergic system on the in vivo modulation of prolactin (PRL) mRNA levels was investigated by quantitative in situ hybridization in the male rat anterior pituitary gland. In situ hybridization was performed using a [(35)S]-labeled cDNA probe encoding PRL. Orchiectomy performed 14 days earlier did not modify PRL mRNA levels. In orchiectomized rats treatment with the dopaminergic agonist bromocriptine for 14 days decreased PRL mRNA levels by 30%, while in intact animals the same treatment did not induce any changes in PRL mRNA levels. Administration of the dopamine D(2) receptor antagonist haloperidol in both intact and orchiectomized rats induced a 4-fold increase in mRNA levels. Administration of dihydrotestosterone to orchiectomized animals which had been treated or not with haloperidol or bromocriptine did not modify PRL mRNA levels. In orchiectomized animals administration of 17ss-estradiol (0.25 mug twice daily) for 14 days caused a 4-fold increase in amounts of PRL mRNA. Administration of bromocriptine to 17ss-estradiol-treated animals induced a 15% decrease of PRL mRNA levels compared to those obtained by 17ss-estradiol administered alone. The concomitant administration of 17ss-estradiol and haloperidol resulted in a 50% increase in PRL mRNA levels compared to those measured in animals treated with haloperidol alone. The present results clearly demonstrate that in vivo estrogen as well as dopamine-mediated mechanisms play a regulatory role in PRL mRNA levels in the male rat.
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Steyaert H, Tonon MC, Tong Y, Smihrouet F, Testart J, Pelletier G, Vaudry H. Distribution and characterization of endogenous benzodiazepine receptor ligand (endozepine)-like peptides in the rat gastrointestinal tract. Endocrinology 1991; 129:2101-9. [PMID: 1915089 DOI: 10.1210/endo-129-4-2101] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Endozepine is the generic name for a family of peptides that are capable of displacing benzodiazepines and the 3-carboxylate ester of beta-carboline from their specific binding sites on synaptosomal membranes. The 104-amino acid polypeptide diazepam-binding inhibitor (DBI) and the octadecaneuropeptide (ODN) generated by tryptic digestion of DBI are two members of the endozepine family. In the present study we have used RIA, HPLC, in situ hybridization, and immunohistochemical techniques to identify and localize endozepine-like molecules in the rat gastrointestinal tract. Significant amounts of endozepine-like immunoreactivity (LI) were detected throughout the gut; the highest concentrations were found in the duodenum and antrum. HPLC analysis revealed that the immunoreactive material eluted as a major peak with a higher retention time than that of synthetic ODN. The distribution of the immunoreactive peptide(s) was studied using the peroxidase-antiperoxidase technique at the light microscope level. Endozepine-LI was localized only in the epithelial cell layer of the intestine in both goblet cells and enterocytes. In the stomach, endozepine-LI appeared to be restricted to deep layer of the epithelial cells. The diffuse neuroendocrine cells (amine precursor uptake and decarboxylation system) as well as myenteric and neuronal cells were devoid of immunoreactivity. A good correlation was observed between RIA and immunocytochemical data, in that the esophagus, which contained very low concentrations of endozepine-LI, also exhibited weak immunostaining of secretory cells. In situ hybridization using a 35S-labeled cRNA probe showed that endozepine mRNA was located in the mucosa. Taken together, these results show that in the rat, epithelial cells synthesize endozepine-LI material. Since epithelial cells also contain a high density of peripheral-type benzodiazepine-binding sites, our data indicate that endozepines may play a role in water, electrolyte, and/or mucus regulation in the rat gastrointestinal tract. The occurrence of high levels of endozepine-LI in the rat stomach also suggests that endozepines can be involved in the regulation of gastric acid secretion through modulation of local gamma-aminobutyric acid-ergic neurotransmission.
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244
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Wu L, Tong Y, Cheng L, Liu J. [Anti-inflammation and toxicity of radix Aconiti coreni and rhizoma Tyhon]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:595-7, 639. [PMID: 1820790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Rats, mice, pigeons and rabbits were employed to study the anti-inflammatory and toxic actions of Radix Aconiti coreni and rhizoma Tyhon. The result shows that Radix Aconiti coreni and rhizoma Tyhon have similar anti-inflammatory action. rhizoma Tyhon has an obvious stimulating effect on eye conjunctiva as well as throat and stomach mucosa, while Radix Aconiti coreni does not.
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245
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Tong Y, Toranzo D, Pelletier G. Localization of diazepam-binding inhibitor (DBI) mRNA in the rat brain by high resolution in situ hybridization. Neuropeptides 1991; 20:33-40. [PMID: 1791923 DOI: 10.1016/0143-4179(91)90037-j] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
An endogenous peptide, named diazepam-binding inhibitor (DBI) capable of displacing benzodiazepines from binding sites has been recently fully characterized. In order to clearly identify the cell types responsible for the biosynthesis of DBI in the rat central nervous system, we have performed high resolution in situ hybridization in the area postrema, hypothalamus and cerebellum, using a [35S]-labeled single stranded RNA probe. Hybridization signal was detected in both semithin and ultrathin sections. In all the brain areas examined, specific labeling was exclusively observed in non-neuronal cells including ependymal and subependymal cells bordering the third ventricle. The results obtained clearly establish that DBI is synthesized by non-neuronal cells in the rat brain.
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246
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Li J, Tong Y, Xing G. [Botanical survey and quality evaluation of Chinese drug shiwei (folium Pyrrosiae)]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:520-2, 573. [PMID: 1804194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper deals with a botanical survey and identification of the Chinese drug Shiwei (Folium Pyrrosiae) on the basis of three most widely used species included in the 1985 edition of Chinese Pharmacopoeia, six species used in some districts of China, and two adulterant species. Three active constituents in seven species of Folium Pyrrosiae (mangiferin, isomangiferin and chlorogenic acid) have been determined.
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247
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Tong Y, Rhéaume E, Simard J, Pelletier G. Localization of peripheral benzodiazepine binding sites and diazepam-binding inhibitor (DBI) mRNA in mammary glands and dimethylbenz(a)antracene (DMBA)-induced mammary tumors in the rat. REGULATORY PEPTIDES 1991; 33:263-73. [PMID: 1652780 DOI: 10.1016/0167-0115(91)90229-a] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
An association of diazepam-binding inhibitor (DBI), an endogenous ligand at the benzodiazepine (BZD) receptor, with the peripheral type BDZ receptor (PBR) has been reported in the brain and a few peripheral tissues. In order to verify whether or not DBI and PBR are present in the mammary tissue, we have proceeded to the localization of DBI mRNA and PBR in rat mammary glands and DMBA-induced mammary tumors. DBI mRNA was detected by in situ hybridization using a 35S-labelled single-stranded RNA probe complementary to DBI mRNA and PBR by in vitro autoradiography using [3H]PK11195 as the ligand. In mammary glands from virgin and lactating animals, both DBI mRNA and PBR were detected in acinar cells. In dimethylbenz(a)anthracene (DMBA)-induced tumors, hybridization signal was not detected in all the cells whereas PBR appeared to be present in all the tumoral cells, although non uniformly distributed. These data indicating that mammary DMBA-induced tumoral cells contain both DBI and PBR suggest that BZD receptors might be involved in the regulation of mammary glands as well as mammary tumoral cells.
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MESH Headings
- 9,10-Dimethyl-1,2-benzanthracene
- Animals
- Autoradiography
- Diazepam Binding Inhibitor
- Female
- Lactation
- Mammary Glands, Animal/metabolism
- Mammary Glands, Animal/ultrastructure
- Mammary Neoplasms, Experimental/chemically induced
- Mammary Neoplasms, Experimental/metabolism
- Mammary Neoplasms, Experimental/ultrastructure
- Neuropeptides/genetics
- Neuropeptides/metabolism
- Nucleic Acid Hybridization
- Pregnancy
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred Strains
- Receptors, GABA-A/metabolism
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248
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Tong Y. [A study of forced tooth movement. An observation of early histo-pathologic and ultrastructural changes in compressed periodontal ligaments of rats]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1991; 26:96-8. [PMID: 1874076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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249
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Wang K, Song W, Tong Y. [Identification of Schisardra by TLC-densitometry]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:70-1, 125. [PMID: 1872965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This paper deals with the determination of the lignins in 10 species of Schisandra crude drugs by TLC-densitometry. The result shows that all the 10 species are unidentical in the lignin constituents; the same species vary in the contents with habitats; and the TLC chromatograms of the 10 species differ distinctly from each other.
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250
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Tong Y. [Determination and identification of alkaloids in folk drug caowu]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:43-5, 64-5. [PMID: 2069703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
By means of HPLC method, yunaconitine and talatisamine contained in 10 samples of folk drug Caowu (aconite) have been analysed. The result shows that in 3 species both yunaconitine and talalisamine are present, and in 7 species only yunaconitine is found. The contents and HPLC chromatograms of these alkaloids vary with the samples.
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