201
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Abstract
Fingerprinting of RNA populations was achieved using an arbitrarily selected primer at low stringency for first and second strand cDNA synthesis. PCR amplification was then used to amplify the products. The method required only a few nanograms of total RNA and was unaffected by low levels of genomic double stranded DNA contamination. A reproducible pattern of ten to twenty clearly visible PCR products was obtained from any one tissue. Differences in PCR fingerprints were detected for RNAs from the same tissue isolated from different mouse strains and for RNAs from different tissues from the same mouse. The strain-specific differences revealed are probably due to sequence polymorphisms and should be useful for genetic mapping of genes. The tissue-specific differences revealed may be useful for studying differential gene expression. Examples of tissue-specific differences were cloned. Differential expression was confirmed for these products by Northern analysis and DNA sequencing uncovered two new tissue-specific messages. The method should be applicable to the detection of differences between RNA populations in a wide variety of situations.
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Affiliation(s)
- J Welsh
- California Institute of Biological Research, La Jolla 92037
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202
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203
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Abstract
The macular neuroepithelium is morphologically organized as a weighted neural network for parallel distributed processing of information. The network is continuous across the striola, where some type II hair cells synapse with calyces containing type I cells with tufts of opposite directional polarities. Whether other hair cell to calyx appositions that lack synapses interact because of intercellular potassium accumulation remains an open question. A functionally important inference of macular organization is that just as arrays of hair cells communicate an entire piece of information to a nerve fiber, so do macular subarrays of nerve fibers (not single units) carry the whole coded message to the brain stem. Moreover, the size of the network subarray can expand or become more limited depending upon the strength and/or duration of the input. It is the functioning of the network and its subarrays that must be understood if we are to learn how maculas carry out their work and adapt to new environments. Simulations of functioning maculas, or subparts, based on precise morphology and known physiology are useful tools to gain insights into macular information processing. The current simulations of afferent collateral electrical activity are a prelude to development of a 3-D model. The simulations demonstrate a relationship between geometry and function, with the diameter of the stem apparently being a major determinant of electrical activity transmitted to the base in the case of collaterals with short stems. Thus, while changes in synaptic number and/or size may be an important adaptive mechanism in an altered g environment, changes in diameter of the stem is another means of altering outflow. Research on the effects of microgravity should be extremely useful in examining the validity of this and other concepts of neural adaptation, since maculas are biological linear accelerometers ideally suited to the task. Maculas are also extremely interesting to study in detail because of the richness of connectivities and submicroscopic organization they present. Many of their features are common with more complex parts of the brain. It seems possible that knowledge of the three-dimensional geometric relationships operative in a functioning macula will contribute much to the understanding of the dynamics underlying more complex behavior. Computerized approaches greatly facilitate this task and provide an objective method of analysis. It is likely that, in the end, simple rules will be found to govern optimal neural architectural organization, even at higher cognitive levels. The architecture only appears complex because we do not yet grasp its meaning.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- M D Ross
- National Aeronautics and Space Administration, Ames Research Center, Moffett Field, California 94035
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204
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Abstract
The authors report striking CT scan findings in a young woman with unilateral Moyamoya disease. Serial CT scans showed features that paralleled the clinical and pathophysiologic evolution of the disorder, in much the same way as has been reported in studies using serial angiograms.
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Affiliation(s)
- I S Shin
- Department of Neurology, State University of New York, Buffalo
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205
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Schlom J, Siler K, Milenic DE, Eggensperger D, Colcher D, Miller LS, Houchens D, Cheng R, Kaplan D, Goeckeler W. Monoclonal antibody-based therapy of a human tumor xenograft with a 177lutetium-labeled immunoconjugate. Cancer Res 1991; 51:2889-96. [PMID: 1851665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
177Lutetium (177Lu) is a member of the family of elements known as lanthanides or rare earths. Monoclonal antibody (MAb) CC49, a murine IgG1, which is reactive with the tumor-associated antigen, TAG-72, has been shown previously to react with a wide range of human carcinomas; CC49 reacts to a different epitope on the TAG-72 molecule than MAb B72.3 and has a higher binding affinity. We report here the first use of a 177Lu-labeled immunoconjugate, 177Lu-CC49, in an experimental therapy model for human carcinoma. 177Lu-CC49 was shown to delay the growth of established LS-174T human colon carcinomas in athymic mice at a single dose of 50 microCi. Overt toxicity was observed with the administration of approximately 500 microCi of 177Lu-CC49 in which 5 of 9 mice died of apparent marrow toxicity. A single administration of 200 or 350 microCi of 177Lu-CC49, however, was shown to eliminate established tumors through the 77-day observation period after MAb administration. Dose fractionation experiments revealed that at least 750 microCi of 177Lu-CC49 (250 microCi/week for 3 consecutive weeks) was well tolerated in that 9 of 10 mice survived. Moreover, this dose schedule was able to eliminate the growth of relatively large (300 mm3) human colon tumor xenografts in 90% of the animals treated. Single-dose and dose fractionation studies were also carried out with an isotype-matched control MAb, 177Lu-MOPC-21. In all dose schedules, a large differential was seen between the therapeutic effects of the 177Lu-CC49 versus that of the 177Lu-control MAb. The merits and limitations of the use of 177Lu-labeled immunoconjugates (in particular, 177Lu-CC49) are discussed in terms of potential novel therapeutics for human carcinoma.
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Affiliation(s)
- J Schlom
- Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
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206
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Ross MD, Cutler L, Doshay D, Cheng R, Naddaf A. A new theory of macular organization based on computer-assisted 3-D reconstruction, Monte Carlo simulation and symbolic modeling of vestibular maculas. Acta Otolaryngol Suppl 1991; 481:11-4. [PMID: 1681670 DOI: 10.3109/00016489109131333] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- M D Ross
- NASA-Ames Research Center, Moffett Field, CA 94035
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207
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Guo Y, Cheng R, Xu G, Zheng Q. [Chemical constituents of Isodon parvifolia (Batalin) Hara]. Zhongguo Zhong Yao Za Zhi 1990; 15:101-3, 127. [PMID: 2390167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Twelve compounds were isolated from the leaves and stems of Isodon parvifolia. This paper deals with the isolation and identification of two diterpenes epinodosinol (I), lasiodonin (II) and two triterpenes alpha-amyrin (XI a) and beta-amyrin (XI b).
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Affiliation(s)
- Y Guo
- Nanjing Institute of Materia Medica
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208
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Kim C, Cheng R, Corrigall WA, Coen KM. Assay for methylnaltrexone in rat brain regions and serum by high-performance liquid chromatography with coulometric electrochemical detection. Chromatographia 1989. [DOI: 10.1007/bf02261014] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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209
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Kim C, Cheng R, George SR. Measurement of methionine enkephalin and leucine enkephalin in rat brain regions by high-performance liquid chromatography with coulometric electrochemical detection. J Chromatogr 1989; 494:67-76. [PMID: 2584346 DOI: 10.1016/s0378-4347(00)82657-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A method is described for the determination of two pentapeptides, methionine enkephalin (H-Tyr-Gly-Gly-Phe-Met-OH) (ME) and leucine enkephalin (H-Tyr-Gly-Gly-Phe-Leu-OH) (LE) in discrete rat brain regions. Separation and quantitation were performed by reversed-phase high-performance liquid chromatography with coulometric detection. Perchloric acid extracts of the tissue after enzyme inactivation by heat treatment were passed through a normal-phase solid-phase extraction diol (COHCOH) column, and endogenous ME and LE were subsequently eluted with methanol. The mobile phase was 1-propanol-phosphate buffer (pH 5.5) (9:91). Eluted samples were detected electrochemically using dual coulometric electrodes operated in screen mode. Each of these enkephalins gave a linear response over the range 40-160 ng/ml cerebellar homogenate (0.8-3.2 ng absolute amount on column). Analytical recoveries of synthetic ME and LE, added to the homogenates, were 70 +/- 3 and 70 +/- 10%, respectively, when compared with enkephalins dissolved in water. The mean between-assay coefficients of variation for synthetic ME and LE were lower than 10.7 and 7.4%, respectively, over the concentration range studied. The within-assay coefficients of variation for synthetic ME and LE were 11.4 and 9.5%, respectively, at the lowest concentration. The present method has been applied to a study determining the levels of endogenous ME and LE in discrete rat brain regions.
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Affiliation(s)
- C Kim
- Addiction Research Foundation, Toronto, Ontario, Canada
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210
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211
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Callanan DL, Cheng R, Brown LW. Recurrent seizures in a 'well-controlled' child. Hosp Pract (Off Ed) 1986; 21:36, 40, 43. [PMID: 3093505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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212
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Yang K, Cheng R, King A. Neck loads in frontal impact. J Biomech 1986. [DOI: 10.1016/0021-9290(86)90096-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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213
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Cole SP, Mirski S, McGarry RC, Cheng R, Campling BG, Roder JC. Differential expression of the Leu-7 antigen on human lung tumor cells. Cancer Res 1985; 45:4285-90. [PMID: 3928154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The HNK-1 monoclonal antibody detects an antigen (Leu-7) on a subpopulation of large granular lymphocytes which have natural killer cell function. Recently this antigen has been found on nonhemopoietic tissues. In the present study human lung tumor cells were examined for the presence of Leu-7 antigen using an enzyme-linked immunosorbent assay, immunoperoxidase staining, and fluorescence-activated cell sorter analysis. All small cell lung tumor cells tested were Leu-7 positive. In contrast only two of seven biopsy specimens from small cell lung cancer patients were Leu-7 positive. Several large cell lung tumor lines were Leu-7 positive while an adenocarcinoma and squamous cell carcinoma were negative. These results indicate that expression of Leu-7 antigen on lung tumor cells is heterogeneous both in vitro and in vivo. Small cell lung tumor lines have been reported to undergo histological conversion in vitro accompanied by the loss of a number of biochemical markers. In our study histologically converted cells exhibited much less reactivity with HNK-1 than did the parent cells. These results indicate that the degree of expression of Leu-7 antigen may be under the control of differentiation-related events. Thus monoclonal antibody HNK-1 has been very useful in studying heterogeneity within and among lung tumor cells.
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214
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Cheng R. Chinese herbalism. Can Fam Physician 1984; 30:119-122. [PMID: 21283498 PMCID: PMC2153990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Chinese herbalism dates back to 2852 B.C. More than 2,600 herbs and thousands of herbal formulae are used to treat illness. Classical theories of Chinese medicine are integrated with the Taoist philosophy, whereby the universe is composed of two basic forces: a positive one called yang, and a negative one called yin. Illness is thought to occur when there is too much yang (tonification) or too much yin (sedation) in the body and herbal medicines are therefore intended either to tonify or to sedate the body so that balance is restored. Since 1954, some Chinese herbal remedies have been scientifically analyzed and tested. Several have been proven effective in treating a variety of diseases and conditions.
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215
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Chylek P, Ramaswamy V, Cheng R, Pinnick RG. Optical properties and mass concentration of carbonaceous smokes. Appl Opt 1981; 20:2980-2985. [PMID: 20333084 DOI: 10.1364/ao.20.002980] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Absorption or extinction measurements at wavelengths of 0.5145 and 10.6 microm lead to determination of the mass concentration of carbonaceous smokes with an accuracy of ~20%. The results do not depend on the details of the particle size distribution or on particulate to void ratio.
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216
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217
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Abstract
It was hypothesized that electroacupuncture releases beta-endorphin and ACTH from the pituitary. Since ACTH induces the release of cortisol from the adrenal glands, blood cortisol level should be enhanced by electroacupuncture. The present result shows that the blood cortisol levels of horses are significantly increased after 30 min of electroacupuncture treatment while the sham treatment (control) shows an insignificant effect.
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218
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Pomeranz B, Cheng R. Suppression of noxious responses in single neurons of cat spinal cord by electroacupuncture and its reversal by the opiate antagonist naloxone. Pain 1979. [DOI: 10.1016/0304-3959(79)90025-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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219
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Pomeranz B, Cheng R. Suppression of noxious responses in single neurons of cat spinal cord by electroacupuncture and its reversal by the opiate antagonist naloxone. Exp Neurol 1979; 64:327-41. [PMID: 428509 DOI: 10.1016/0014-4886(79)90273-5] [Citation(s) in RCA: 109] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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220
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Cheng R, Pomeranz B, Yü G. Dexamethasone partially reduces and 2% saline-treatment abolished electroacupunture analgesia: these findings implicate pituitary endorphins. Life Sci 1979; 24:1481-6. [PMID: 470547 DOI: 10.1016/0024-3205(79)90031-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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221
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Pomeranz B, Cheng R, Law P. Acupuncture reduces electrophysiological and behavioral responses to noxious stimuli: pituitary is implicated. Exp Neurol 1977; 54:172-8. [PMID: 832694 DOI: 10.1016/0014-4886(77)90243-6] [Citation(s) in RCA: 184] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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222
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223
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224
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225
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Lu ML, Shyu PP, Hou HM, Cheng R. [Direct amperometric titration of amines with sodium tetraphenyloborate solution]. Yao Xue Xue Bao 1965; 12:713-9. [PMID: 5899054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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