476
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Gong Y, Vikkula M, Boon L, Liu J, Beighton P, Ramesar R, Peltonen L, Somer H, Hirose T, Dallapiccola B, De Paepe A, Swoboda W, Zabel B, Superti-Furga A, Steinmann B, Brunner HG, Jans A, Boles RG, Adkins W, van den Boogaard MJ, Olsen BR, Warman ML. Osteoporosis-pseudoglioma syndrome, a disorder affecting skeletal strength and vision, is assigned to chromosome region 11q12-13. Am J Hum Genet 1996; 59:146-51. [PMID: 8659519 PMCID: PMC1915094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Osteoporosis-pseudoglioma syndrome (OPS) is an autosomal recessive disorder characterized by severe juvenile-onset osteoporosis and congenital or juvenile-onset blindness. The pathogenic mechanism is not known. Clinical, biochemical, and microscopic analyses suggest that OPS may be a disorder of matrix homeostasis rather than a disorder of matrix structure. Consequently, identification of the OPS gene and its protein product could provide insights regarding common osteoporotic conditions, such as postmenopausal and senile osteoporosis. As a first step toward determining the cause of OPS, we utilized a combination of traditional linkage analysis and homozygosity mapping to assign the OPS locus to chromosome region 11q12-13. Mapping was accomplished by analyzing 16 DNA samples (seven affected individuals) from three different consanguineous kindreds. Studies in 10 additional families narrowed the candidate region, supported locus homogeneity, and did not detect founder effects. The OPS locus maps to a 13-cM interval between D11S1298 and D11S971 and most likely lies in a 3-cM region between GSTP1 and D11S1296. At present, no strong candidate genes colocalize with OPS.
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477
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Gong Y, Owens DW, Weaver JH. Etching of double-height-stepped Si(100)-2 x 1: Steps and their interactions. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:R16144-R16147. [PMID: 9983518 DOI: 10.1103/physrevb.53.r16144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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478
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Li XM, Salido EC, Gong Y, Kitada K, Serikawa T, Yen PH, Shapiro LJ. Cloning of the rat steroid sulfatase gene (Sts), a non-pseudoautosomal X-linked gene that undergoes X inactivation. Mamm Genome 1996; 7:420-4. [PMID: 8662223 DOI: 10.1007/s003359900125] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Although the human steroid sulfatase (STS) gene has been cloned and characterized in detail, several attempts to clone its mouse homologue, with either anti-human STS antibodies or human STS cDNA probes, have failed, suggesting a substantial divergence between these genes. However, partial amino-terminal sequence from purified rat liver STS is very similar to its human counterpart, and sequence comparisons have revealed several domains that are conserved among all the sulfatases characterized to date. Thus, we used a degenerate-primer RT-PCR approach to amplify a 321-bp fragment from rat liver cDNA, which was used as a probe to clone and characterize the complete cDNA. Comparison of the protein coding region between the rat and human genes showed 66% homology both at the DNA and the protein levels. STS activity was conferred to STS(-) A9 cells upon transfection with a rat Sts expression construct, indicating the authenticity of the cloned cDNA. While Sts has been shown to be located in the mouse pseudoautosomal region, both physical and genetic mapping demonstrate that Sts is not pseudoautosomal in the rat. The overall genomic organization of rat Sts and human STS is very similar, except that the insertion site for intron 1 in the rat is 26 bp upstream from that in the human. Rat Sts is only 8.2 kb long, while the human STS spans over 146 kb.
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479
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Gong Y, Cui L, Minuk GY. Comparison of glyceraldehyde-3-phosphate dehydrogenase and 28s-ribosomal RNA gene expression in human hepatocellular carcinoma. Hepatology 1996; 23:734-7. [PMID: 8666326 DOI: 10.1002/hep.510230413] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The gene responsible for transcribing glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is commonly used as a reporter gene to estimate the amount of RNA present in Northern analyses. However, recent data suggest that GAPDH gene expression may vary with the extent of cell proliferation and differentiation. 28S-ribosomal RNA (28S-rRNA) has also been employed to normalize Northern blots prepared with total RNA. In the present study, we compared the expression of GAPDH messenger RNA (mRNA) with 28S-rRNA by Northern blot analyses in human hepatocellular carcinoma tissues (HCC) and adjacent non-HCC tissues from eight patients with chronic viral hepatitis-induced cirrhosis and normal liver tissue from eight healthy control subjects. The results of the study revealed that GAPDH mRNA levels in HCC were significantly higher (14X-16x) than those in adjacent non-HCC and normal liver tissues. Conversely, 28S-rRNA levels did not vary among HCC, adjacent non-HCC, and normal liver tissues. We also demonstrated that the 28S-RNA signal was proportional to the amount of RNA loaded. These findings indicate that 28S-rRNA, rather than GAPDH mRNA, should be used as RNA loading controls for Northern blot analyses involving HCC and nontumor tissues. The findings also raise the possibility that GAPDH mRNA gene expression might serve as a diagnostic indicator for human HCC.
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480
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Li XM, Alperin ES, Salido E, Gong Y, Yen P, Shapiro LJ. Characterization of the promoter region of human steroid sulfatase: a gene which escapes X inactivation. SOMATIC CELL AND MOLECULAR GENETICS 1996; 22:105-17. [PMID: 8782490 DOI: 10.1007/bf02369901] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The human X-linked steroid sulfatase gene (STS) was among the first genes shown to escape X inactivation. At least fourteen genes regulated in this fashion have now been recognized. They are dispersed into several regions of the X chromosome and may be controlled in a locus specific manner. Studies of the promoters of these genes could provide insights into the mechanism of X inactivation, however little information of this nature is currently available. For this reason we examined 5' flanking sequences of the human STS gene for promoter function. Four transcription start sites scattered over a 50bp region were identified. Functional domains of this TATA-less and GC poor promoter were identified by study of a series of terminal and internal deletions. A putative promoter sequence was identified which by itself exhibits little or no basal activity. However when combined with upstream regulatory elements, this segment showed weak but reproducible activity in a CAT (chloramphenicol acetyltransferase) reporter assay. Several regulatory domains acting as enhancers and repressors were subsequently identified. The relationship of this 5' sequence to the ability of the STS gene to escape X-inactivation is discussed.
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481
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Liu J, Prakash O, Cai M, Gong Y, Huang Y, Wen L, Wen JJ, Huang JK, Krishnamoorthi R. Solution structure and backbone dynamics of recombinant Cucurbita maxima trypsin inhibitor-V determined by NMR spectroscopy. Biochemistry 1996; 35:1516-24. [PMID: 8634282 DOI: 10.1021/bi952466d] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The solution structure of recombinant Cucurbita maxima trypsin inhibitor-V (rCMTI-V), whose N-terminal is unacetylated and carries an extra glycine residue, was determined by means of two-dimensional (2D) homo and 3D hetero NMR experiments in combination with a distance geometry and simulated annealing algorithm. A total of 927 interproton distances and 123 torsion angle constraints were utilized to generate 18 structures. The root mean squared deviation (RMSD) of the mean structure is 0.53 A for main-chain atoms and 0.95 A for all the non-hydrogen atoms of residues 3-40 and 49-67. The average structure of rCMTI-V is found to be almost the same as that of the native protein [Cai, M., Gong, Y., Kao, J.-L., & Krishnamoorthi, R. (1995) Biochemistry 34, 5201-5211]. The backbone dynamics of uniformly 15N-labeled rCMTI-V were characterized by 2D 1H-15N NMR methods. 15N spin-lattice and spin-spin relaxation rate constants (R1 and R2, respectively) and [1H]-15N steady-state heteronuclear Overhauser effect enhancements were measured for the peptide NH units and, using the model-free formalism [Lipari, G., & Szabo, A. (1982) J. Am. Chem. Soc. 104, 4546-4559, 4559-4570], the following parameters were determined: overall tumbling correlation time for the protein molecule (tau m), generalized order parameters for the individual N-H vectors (S2), effective correlation times for their internal motions (tau e), and terms to account for motions on a slower time scale (second) due to chemical exchange and/or conformational averaging (R(ex)). Most of the backbone NH groups of rCMTI-V are found to be highly constrained ((S2) = 0.83) with the exception of those in the binding loop (residues 41-48, (S2) = 0.71) and the N-terminal region ((S2) = 0.73). Main-chain atoms in these regions show large RMSD values in the average NMR structure. Residues involved in turns also appear to have more mobility ((S2) = 0.80). Dynamical properties of rCMTI-V were compared with those of two other inhibitors of the potato I family--eglin c [Peng, J. W., & Wagner, G. (1992) Biochemistry 31, 8571-8586] and barley chymotrypsin inhibitor 2 [CI-2; Shaw, G. L., Davis, B., Keeler, J., & Fersht, A. R. (1995) Biochemistry 34, 2225-2233]. The Cys3-Cys48 linkage found only in rCMTI-V appears to somewhat reduce the N-terminal flexibility; likewise, the C-terminal of rCMTI-V, being part of a beta-sheet, appears to be more rigid.
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482
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Xue Q, Gong Y, Drake DL, Qian J, Coleman RV. Impurity-induced modulations in PdxNbSe3 coupled to charge-density-wave formation. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:1068-1071. [PMID: 9983557 DOI: 10.1103/physrevb.53.1068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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483
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Guo R, Zhang L, Gong Y, Zhang B. The treatment of pain in bone metastasis of cancer with the analgesic decoction of cancer and the acupoint therapeutic apparatus. J TRADIT CHIN MED 1995; 15:262-4. [PMID: 8709605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The pain in 286 cases of bone metastasis of cancer was treated with an analgesic decoction of herbal drugs in combination with the Acupoint Therapeutic Apparatus that generated low frequency electric impulses into the acupoints. This series of patients comprised 104 cases of medium pain and 182 cases of severe pain, which was practically or completely relieved in 17 or 29 minutes respectively after the treatment; the total effective rate was 74.2% for 212 cases, and the duration of analgesic effect lasted 2.7 hours to 5.2 hours, averaging 3.6 hours. The cases that needed considerable dosages of analgesic tablets or sedatives markedly reduced their requests of such drugs. Determination of bone marrow stem cells indicated that the herbal treatment produced effects of promoting and protecting the stem cells. The rate of lymphocyte transformation was 45-76% before the treatment and rose to 57-96% after the treatment, demonstrating an increase of 15.2%, which was statistically significant (P < 0.001). The analgesic effect of the decoction was not correlated to the age and sex of the patients or the variety of cancer, except that it was not effective for uterine carcinoma. The main side effects included nausea, vomiting, somnolence, and numbness of the tongue.
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484
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Brewton RG, Wood BM, Ren ZX, Gong Y, Tiller GE, Warman ML, Lee B, Horton WA, Olsen BR, Baker JR. Molecular cloning of the alpha 3 chain of human type IX collagen: linkage of the gene COL9A3 to chromosome 20q13.3. Genomics 1995; 30:329-36. [PMID: 8586434 DOI: 10.1006/geno.1995.9870] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Type IX collagen is composed of three polypeptides derived from the human genes COL9A1, COL9A2, and COL9A3 that assemble to form a mature collagen molecule with the structure alpha 1(IX)alpha 2(IX)alpha 3(IX). We have identified overlapping cDNA and genomic clones that encode for the entire alpha 3 chain of human type IX collagen. Tryptic peptides from the human alpha 3(IX) collagen chain were subjected to N-terminal amino acid sequencing, and a stretch of 124 contiguous amino acids that included the NC1, COL1, and NC2 domains was obtained. Degenerate oligonucleotide primers were designed based on the amino acid sequences of the human tryptic peptides as well as bovine peptides and sequences from chicken cDNA clones. These primers were used to amplify three overlapping PCR products that covered the majority of the human alpha 3(IX) collagen. PCR products were then used to identify overlapping cDNA clones from a human chondrocyte library. A lambda genomic clone was identified that contained the 5'-most exon that encodes the signal peptide to complete the entire structure of the human alpha 3(IX) collagen chain. Genomic amplification identified a single-strand conformational polymorphism in COL1 that was used to map COL9A3 to chromosome 20q13.3 by linkage analysis. The present study completes the structure of human type IX collagen, and linkage for COL9A3 completes the genomic mapping of cartilage collagen genes. These data will greatly assist the genetic screening of families with degenerative cartilage and eye diseases by allowing investigators to screen for a complete set of candidate collagen gene markers.
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485
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Cai M, Gong Y, Prakash O, Krishnamoorthi R. Reactive-site hydrolyzed Cucurbita maxima trypsin inhibitor-V: function, thermodynamic stability, and NMR solution structure. Biochemistry 1995; 34:12087-94. [PMID: 7547948 DOI: 10.1021/bi00038a001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Reactive-site (Lys44-Asp45 peptide bond) hydrolyzed Cucurbita maxima trypsin inhibitor-V (CMTI-V*) was prepared and characterized: In comparison to the intact form, CMTI-V* exhibited markedly reduced inhibitory properties and binding affinities toward trypsin and human blood coagulation factor XIIa. The equilibrium constant of trypsin-catalyzed hydrolysis, Khyd, defined as [CMTI-V*]/[CMTI-V], was measured to be approximately 9.4 at 25 degrees C (delta G degrees = -1.3 kcal.mol-1). From the temperature dependence of delta G degrees, the following thermodynamic parameters were estimated: delta H degrees = 1.6 kcal.mol-1 and delta S degrees = 9.8 eu. In order to understand the functional and thermodynamic differences between the two forms, the three-dimensional solution structure of CMTI-V* was determined by a combined approach of NMR, distance geometry, and simulated annealing methods. Thus, following sequence-specific and stereospecific resonance assignments, including those of beta-, gamma-, delta-, and epsilon-hydrogens and valine methyl hydrogens, 809 interhydrogen distances and 123 dihedral angle constraints were determined, resulting in the computation and energy-minimization of 20 structures for CMTI-V*. The average root mean squared deviation in position for equivalent atoms between the 20 individual structures and the mean structure obtained by averaging their coordinates is 0.67 +/- 0.15 A for the main chain atoms and 1.19 +/- 0.23 A for all the non-hydrogen atoms of residues 5-40 and residues 48-67.(ABSTRACT TRUNCATED AT 250 WORDS)
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486
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Gong Y, Zhou HX, Guo M, Kallenbach NR. Structural analysis of the N- and C-termini in a peptide with consensus sequence. Protein Sci 1995; 4:1446-56. [PMID: 8520470 PMCID: PMC2143179 DOI: 10.1002/pro.5560040802] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We present a structural analysis of a peptide, the sequence of which includes amino acids that show preferences for specific positions near the N- and C-termini in protein helices. This peptide has the sequence ac-YMSEDELKAAEAAFKRHGVP-amide, which includes a strong version of an N-terminal Harper-Rose capping box structure as well as a Gly located close to the C-terminus designed to elucidate its role in C-terminal capping. The sequence of five residues at the middle is inserted to separate effects at the two ends via a helix-stabilizing linker. Application of a simulated annealing procedure using interproton distance constraints derived from 1H NOESY experiments in water reveals the presence of a C-terminal structure in this model. The C-terminus forms a folded back structure in a significant fraction of structures generated by the annealing, in most of which Gly assumes an alpha L conformation. This structure occurs within a highly flexible region of the molecule and hence is occupied only a fraction of the time.
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487
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Gong Y. Radiotherapy of midline malignant reticulosis. Chin Med J (Engl) 1995; 108:542-3. [PMID: 7555275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The results of radiotherapy made on 23 patients with midline malignant reticulosis showed that the 1-, 3-, 5- and 8-year survival rates were 91.3%, 63.2%, 50.0% and 40.0%, respectively. The optimum radiation dose was 50-60 Gy / 5-6 weeks. Chemotherapy with CCNU following the radiotherapy facilitated the healing of lesion, reduced local recurrence and distant metastasis, improved the therapeutic effect and raised the survival rate.
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488
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Gong Y, Guo R, Zhang L. Application of jiang ya paste onto yongquan acupoint for treatment of primary hypertension. J TRADIT CHIN MED 1995; 15:112-3. [PMID: 7650957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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489
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Song W, Cai Y, Deng X, Gong Y, Dong G. [Structural changes of extra pulmonary artery and pulmonary arterioles of rats during chronic hypoxia and their significance]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1995; 17:197-203. [PMID: 8706155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The structural changes of extra pulmonary artery (PA) and pulmonary arterioles and their effects on the pulmonary arterial pressure (PAP) under chronically hypobaric hypoxia (5000 m) were studied. The results showed that (1) The endothelial edema of extra PA and pulmonary arterioles gradually reduced and the endothelial proliferation took place along with the prolongation of hypoxic exposure followed by the recovery of endothelium-dependent relaxation evoked by Ach from depression. This result suggested that the release of E-DRFs from endothelium increased with the structural changes of endothelium in the course of hypoxic exposure, which may be a reason why PAP did not increase any more after 21 to 40 of days exposure. However, the strengthened contraction of PA, the proliferation of cells on the vascular wall, and the muscularity of pulmonary arterioles being related to the hypoxic endothelium may produce a negative effect on decrease of PAP, resulting in persistently higher PAP. (2) The structural changes of pulmonary arteriole endothelium were more severe than those of extra PA endothelium, indicating that pulmonary arterioles might be more sensitive to the stimulation of hypoxia.
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490
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Gong Y, Xue Q, Drake DL, Qian J, Coleman RV. Impurity-induced modulations in NbSe3 detected by atomic-force microscopy. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 51:12975-12988. [PMID: 9978092 DOI: 10.1103/physrevb.51.12975] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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491
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Gong Y, Blok LJ, Perry JE, Lindzey JK, Tindall DJ. Calcium regulation of androgen receptor expression in the human prostate cancer cell line LNCaP. Endocrinology 1995; 136:2172-8. [PMID: 7720667 DOI: 10.1210/endo.136.5.7720667] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Elevation of intracellular calcium levels in the presence of normal androgen levels has been implicated in apoptotic prostate cell death. Since the androgen receptor (AR) plays a critical role in the regulation of growth and differentiation of the prostate, it was of interest to determine whether Ca2+ would affect the expression of androgen receptor messenger RNA (mRNA) and protein, thus affecting the ability of androgens to control prostate function. AR-positive human prostate cancer cells, LNCaP, were incubated with either the calcium ionophore A23187 or the intracellular endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin. Subsequently, AR mRNA and protein levels were assessed by Northern and Western blot analysis. Both A23187 and thapsigargin were found to down-regulate steady state AR mRNA levels in a time- and dose-dependent manner. AR mRNA began to decrease after 6-8 h of incubation with 10(-6) M A23187 or 10(-7) M thapsigargin, reaching a nadir at 16 and 10 h of incubation, respectively. In contrast, control mRNA (glyceraldehyde 3-phosphate dehydrogenase) did not change significantly during the treatments with either A23187 or thapsigargin. AR protein levels were found to be decreased after 12 h of incubation with either 10(-6) M A23187 or 10(-7) M thapsigargin. The decrease in AR mRNA and protein seemed to precede apoptosis, since neither A23187 (24 h) nor thapsigargin (30 h) was found to alter cell morphology within the treatment time. Cycloheximide and actinomycin D were unable to change the calcium-mediated decrease in AR mRNA, ruling out the necessity for de novo protein synthesis or a change in mRNA stability. Moreover, the decrease in AR mRNA induced by calcium does not seem to involve protein kinase C- or calmodulin-dependent pathways, since inhibitors of these cellular components had no effect. Nuclear run-on assays demonstrated little or no effects of either A23187 or thapsigargin treatment on AR gene transcription (8 h and 10 h). In conclusion, these studies show that intracellular calcium seems to be a potent regulator of AR gene expression in LNCaP cells.
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492
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Cai M, Liu J, Gong Y, Krishnamoorthi R. A practical method for stereospecific assignments of gamma- and delta-methylene hydrogens via estimation of vicinal 1H-1H coupling constants. JOURNAL OF MAGNETIC RESONANCE. SERIES B 1995; 107:172-8. [PMID: 7599951 DOI: 10.1006/jmrb.1995.1074] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Stereospecific assignments are made for gamma- and delta-methylene hydrogens in a protein by means of estimation of vicinal 1H-1H spin-spin coupling constants from a short-mixing-time TOCSY experiment. 3J alpha beta coupling constants, as measured from a P.E. COSY map, are shown to be well correlated with alpha-beta cross-peak intensities of a short-mixing-time (10 ms) TOCSY map. The procedure is illustrated by application to a trypsin-inhibitor protein (M(r) approximately 7 Kd). Thus, gamma-methylene hydrogens of isoleucine residues have been stereospecifically assigned on the basis of 3J beta gamma 1H-1H coupling patterns and intraresidue cross-peak intensities in a NOESY map; gamma-hydrogens of other residues, such as lysine and arginine, have been stereospecifically assigned solely on the basis of cross-peak intensity patterns resulting from coupling of two beta-hydrogens to two gamma-hydrogens, and in conjunction with stereospecific assignments of beta-methylene hydrogens. However, intraresidue NOE intensities are needed if one or two pairs of coupling constants cannot be estimated because of cross peaks either overlapping or occurring proximal to the diagonal. The delta-methylene hydrogens have been stereospecifically assigned on the basis of coupling between two gamma-hydrogens and two delta-hydrogens, in combination with stereospecific assignments of gamma-hydrogens. Stereospecific assignments of side chains should contribute to the overall precision and accuracy of NMR-determined three-dimensional solution structures of proteins.
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493
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Cai M, Gong Y, Kao JL, Krishnamoorthi R. Three-dimensional solution structure of Cucurbita maxima trypsin inhibitor-V determined by NMR spectroscopy. Biochemistry 1995; 34:5201-11. [PMID: 7711040 DOI: 10.1021/bi00015a034] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The solution structure of Cucurbita maxima trypsin inhibitor-V (CMTI-V), which is also a specific inhibitor of the blood coagulation protein, factor XIIa, was determined by 1H NMR spectroscopy in combination with a distance-geometry and simulated annealing algorithm. Sequence-specific resonance assignments were made for all the main-chain and most of the side-chain hydrogens. Stereospecific assignments were also made for some of the beta-, gamma-, delta-, and epsilon-hydrogens and valine methyl hydrogens. The ring conformations of all six prolines in the inhibitor were determined on the basis of 1H-1H vicinal coupling constant patterns; most of the proline ring hydrogens were stereospecifically assigned on the basis of vicinal coupling constant and intraresidue nuclear Overhauser effect (NOE) patterns. Distance constraints were determined on the basis of NOEs between pairs of hydrogens. Dihedral angle constraints were determined from estimates of scalar coupling constants and intraresidue NOEs. On the basis of 727 interproton distance and 111 torsion angle constraints, which included backbone phi angles and side-chain chi 1, chi 2, chi 3, and chi 4 angles, 22 structures were calculated by a distance geometry algorithm and refined by energy minimization and simulated annealing methods. Both main-chain and side-chain atoms are well-defined, except for a loop region, two terminal residues, and some side-chain atoms located on the molecular surface. The average root mean squared deviation in the position for equivalent atoms between the 22 individual structures and the mean structure obtained by averaging their coordinates is 0.58 +/- 0.06 A for the main-chain atoms and 1.01 +/- 0.07 A for all the non-hydrogen atoms of residues 3-40 and 49-67. These structures were compared to the X-ray crystallographic structure of another protein of the same inhibitor family-chymotrypsin inhibitor-2 from barley seeds [CI-2; McPhalen, C. A., & James, M. N. G. (1987) Biochemistry 26, 261-269]. The main-chain folding patterns are highly similar for the two proteins, which possess 62% sequence differences. However, major differences are noted in the N- and C-terminal segments, which may be due to the presence of a disulfide bridge in CMTI-V, but not in CI-2.
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494
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Abstract
HIV-1 RNA extraction methodology, stability and cellular location in plasma were studied by quantitative analysis using reverse transcriptase (RT) and polymerase chain reaction (PCR). HIV-1 RNA as intact virus was stable in plasma at room temperature for at least for 24 h, or stable in RNAzol (Tel-Test, Inc. Texas) at -70 degrees C for at least 6 months. The HIV-1 RNA PCR signal did not decline significantly after freezing and thawing of the virus in plasma or in RNAzol. To assess the effect of plasma constituents from different individuals upon quantitative PCR, identical copy members of HIV LAI were spiked into plasma from 9 different, normal individuals. PCR detection of HIV-1 RNA did not show any significant variation in quantitative signals. Additionally, platelet-rich plasma from three seropositive subjects was fractionated into a platelet-free plasma fraction and a platelet pellet fraction. The quantitative analysis of HIV-1 RNA in these fractions, and in the corresponding peripheral blood lymphocytes (PBLs) from each patient, demonstrated that the majority of the HIV-1 RNA was distributed in the plasma, and the HIV-1 RNA in the plasma of these patients seemed not to be strongly platelet associated.
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495
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Cai M, Gong Y, Krishnamoorthi R. Identification of hydrogen-bonded lysine and arginine residues in a protein by means of chi 4-torsional-angle determination. JOURNAL OF MAGNETIC RESONANCE. SERIES B 1995; 106:297-9. [PMID: 7719629 DOI: 10.1006/jmrb.1995.1048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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496
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Gong Y, Deng C, Li S, Li L, Guan J. [Radiolabelling and assay of Chinese agkistrodon acutus venom with carrier-free Na 125I]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1995; 26:116-9. [PMID: 7657328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Chinese agkistroden acutus venom (CAAV) was radiolabelled with carrier-free Na 125I by the method of Iodogen. The specific activity and radiochemical purity for radiolabelled products were 4236.5 x 10(10) Bq/mmol and 98%, respectively. Each CAAV molecule carried 0.52 125I atom. Physical and chemical characterization of radiolabelled CAAV was similar to unradiolabelled CAAV. Binding analysis showed that 125I-CAAV was bound to platelet in a saturable manner. Binding sites per platelet were 13,255 +/- 6292/platelet. The dissociation constant (Kd) was 3.2 +/- 0.69 x 10(-10) mol/L. These results are similar to binding sites of other snake venom on platelet. The investigation showed that radiolabelled CAAV made by our laboratory was useful for radioligand binding assay.
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497
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Wen L, Lee I, Chen G, Huang JK, Gong Y, Krishnamoorthi R. Changing the inhibitory specificity and function of Cucurbita maxima trypsin inhibitor-V by site-directed mutagenesis. Biochem Biophys Res Commun 1995; 207:897-902. [PMID: 7864895 DOI: 10.1006/bbrc.1995.1270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cucurbita maxima trypsin inhibitor-V (CMTI-V) is also a specific inhibitor of human blood coagulation factor beta-factor XIIa. A recombinant version of CMTI-V has allowed probing of roles of individual amino acid residues including the reactive site residue, lysine (P1), by site-directed mutagenesis. The K44R showed at least a 5-fold increase in inhibitory activity toward human beta-factor XIIa, while there was no change toward bovine trypsin. This result demonstrates that beta-factor-XIIa prefers an arginine residue over lysine residue, while trypsin is non-specific to lysine or arginine in its binding pocket. On the other hand, the specificity of CMTI-V could be changed from trypsin to chymotrypsin inhibition by mutation of the P1 residue to either leucine or methionine (K44L or K44M).
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498
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Dubin NH, Bornstein DR, Gong Y. Use of endotoxin as a positive (toxic) control in the mouse embryo assay. J Assist Reprod Genet 1995; 12:147-52. [PMID: 7670274 DOI: 10.1007/bf02211385] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
PURPOSE The mouse embryo assay (MEA) is used to test media used for in vitro fertilization (IVF). Negative controls usually consist of previously tested media known to support growth of embryos to the blastocyst stage by 72 h. Often, no concurrent positive (toxic) controls are reported. Thus, any unusually hardy cohort of embryos may go undetected. Endotoxin was tested for its suitability as a positive control in the MEA. RESULTS Female mice were stimulated with gonadotropins mated with males, and embryos flushed from their oviducts 36 h after HCG injection. Two-cell embryos were pooled and randomly distributed to culture dishes containing media without protein supplement. Endotoxin inhibited blastocyst growth beginning at 50 micrograms/ml, with complete suppression of development at 5000 micrograms/ml. With 500 micrograms/ml endotoxin, an average of 34.8% of the embryos developed to the blastocyst stage for eight separate assays. The interassay coefficient of variation (CV) was 76%, while the intraassay CV was 9.4%. At 48 h the zona pellucida was absent from all of the embryos exposed to the endotoxin. A large difference was found between two lots of endotoxin with the same claimed potency. CONCLUSIONS These studies demonstrate the importance for inclusion of a well-defined positive control when performing the mouse embryo assay.
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499
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Gong Y, Herberman RR, Reynolds CW. The kinetics of cytoplasmic granule secretion in natural killer cytotoxicity. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1994; 9:147-51. [PMID: 7865833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Antiserum against purified cytoplasmic granules from rat LGL tumor cells, and protein A-gold immunoelectron microscopy were used to study the secretory events in lysis of YAC-1 tumor cells by rat LGL tumor cells or by isolated LGL from normal rats. After 30 min incubation of effector and target cells together, gold-labeled cytoplasmic granules were often seen concentrated in the area of the LGL adjacent to the bound YAC-1 target. Within 60 min, the granules were observed to move to the cell border near the conjugated site. At this point, the granules were fused with the cell membrane, and subsequently released the gold-labeled contents into the junction between the LGL and the target cell. Gold particles could be seen at the E-T interface, on the LGL surface, or sometimes on the target cell surface. These data provide direct evidence for the hypothesis that under conditions of active cytotoxicity, natural killer cells secrete their cytoplasmic granule contents leading to the deposition of granule material on the target cell surface and the eventual lysis of the cell.
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500
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Wang Q, Gong Y, Niu K. The Yantai model of community care for rural psychiatric patients. Br J Psychiatry Suppl 1994:107-13. [PMID: 7946222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The main characteristics of the Yantai model are (a) a three-tier (county, township, village) management structure; (b) the vertical integration of community mental health workers, including a professional advisory group of psychiatrists from the central psychiatric hospital, groups of community psychiatrists at small county psychiatric hospitals, non-psychiatric physicians who run psychiatric out-patient clinics at township general hospitals, and village paramedics ('village doctors') who supervise patients in the community; (c) ongoing training of all community mental health workers; (d) registration and yearly follow-up of all patients with mental illnesses in the community; (e) provision of home-care services to a proportion of acutely ill patients; and (f) most of the cost of the service is borne by the state. The network of services provided by this model makes it convenient for patients to obtain treatment and, if necessary, go into hospital; it reduces the economic burden on the family and the community; it combines treatment, prevention, rehabilitation, and supervision under one administrative network; and it decreases the overall level of psychopathology and psychosocial dysfunction in the community.
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