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Chu S, Wilson DS, Deaton RL, Mackenthun AV, Eason CN, Cavanaugh JH. Single- and multiple-dose pharmacokinetics of clarithromycin, a new macrolide antimicrobial. J Clin Pharmacol 1993; 33:719-26. [PMID: 8408732 DOI: 10.1002/j.1552-4604.1993.tb05613.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The pharmacokinetics of clarithromycin and its active 14(R)-hydroxy metabolite were evaluated after single and multiple oral doses of 250 and 500 mg of clarithromycin. Multiple-dose regimens used 12-hour dosing intervals for 7 doses. Plasma and urine concentrations were measured using high-performance liquid chromatography. Appearance of clarithromycin and its metabolite in plasma were rapid, as reflected by mean times to maximum plasma concentration ranging from 1.8 to 2.6 and 1.8 to 2.9 hours, respectively. The rises in clarithromycin peak plasma concentration (Cmax) and area under the plasma concentration versus time curve (AUC) were disproportionate to increase in dose, suggesting nonlinearity in parent compound pharmacokinetics. Clarithromycin terminal disposition half-life (t1/2) also exhibited dose dependency, ranging from harmonic means of 2.7 to 4.8 hours. In contrast, based on Cmax AUC, and predicted/observed accumulation ratios, nonlinearity in metabolite pharmacokinetics was not observed. Plasma accumulation of metabolite occurred to a much lesser degree than that of the parent compound despite a substantially longer t1/2 for the metabolite (metabolite accumulation ratios based on AUC dose 7/AUC dose 1:250-mg regimen = 1.03 +/- 0.33, 500-mg regimen = 0.81 +/- 0.29, parent accumulation ratios: 250-mg regimen = 1.64 +/- 0.47, 500-mg regimen = 1.65 +/- 0.69). This would suggest that formation of this metabolite is capacity-limited and that this may in part account for the nonlinearity observed in clarithromycin pharmacokinetics. Urinary excretion constituted a relatively important route of elimination of clarithromycin, with renal clearance accounting for 17 to 31% of apparent total body clearance.
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Fee MS, Chu S, Mills AP, Chichester RJ, Zuckerman DM, Shaw ED, Danzmann K. Measurement of the positronium 1 (3)S1-2 (3)S1 interval by continuous-wave two-photon excitation. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1993; 48:192-219. [PMID: 9909589 DOI: 10.1103/physreva.48.192] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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203
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Chilco PJ, Gerardi JM, Kaczmarczyk SJ, Chu S, Leopold V, Zajac JD. Calcitonin increases transcription of parathyroid hormone-related protein via cAMP. Mol Cell Endocrinol 1993; 94:1-7. [PMID: 7690720 DOI: 10.1016/0303-7207(93)90045-l] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Transcriptional regulation of the human parathyroid hormone-related protein (PTHrP) gene by calcitonin was examined in a lung cancer line (BEN cells). Northern analysis demonstrated that calcitonin caused a rapid 4.5-fold elevation in PTHrP mRNA. Transient transfection of a construct containing 1119 base pairs of the human PTHrP gene 5' to the ATG start site of translation, fused to the CAT reporter sequence, was used to demonstrate a five-fold increase in transcription by calcitonin. Similar increases were also observed when transfected cells were exposed to a number of cAMP agonists including forskolin, as well as isobutyl-methylxanthine. A putative cAMP responsive element (5'-TGACTTCA-3') present within exon 4 was placed upstream of the heterologous SV40 promoter. Expression of this construct was elevated 4.5-fold in response to calcitonin and 7-fold in response to forskolin. Similar responses to calcitonin occurred with a smaller construct (pZMR30) containing 530 bp of sequence upstream of the ATG start site. Thus we postulate that calcitonin acts at least partially via cAMP through this element in exon 4 of the human PTHrP gene.
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204
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Weiss DS, Young BC, Chu S. Precision measurement of the photon recoil of an atom using atomic interferometry. PHYSICAL REVIEW LETTERS 1993; 70:2706-2709. [PMID: 10053632 DOI: 10.1103/physrevlett.70.2706] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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205
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Dittmer D, Pati S, Zambetti G, Chu S, Teresky AK, Moore M, Finlay C, Levine AJ. Gain of function mutations in p53. Nat Genet 1993; 4:42-6. [PMID: 8099841 DOI: 10.1038/ng0593-42] [Citation(s) in RCA: 634] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We report that the expression of murine or human mutant p53 proteins in cells with no endogenous p53 proteins confers new or additional phenotypes upon these cells. Mutant p53 proteins expressed in cell lines lacking p53 resulted in either enhanced tumorigenic potential in nude mice ((10)3 cells) or enhanced plating efficiency in agar cell culture (human SAOS-2 cells). Also, mutant human p53 alleles, unlike the wild-type p53 protein, could also enhance the expression of a test gene regulated by the multi-drug resistance enhancer-promoter element. These data demonstrate a gain of function associated with p53 mutations in addition to the loss of function shown previously to be associated with mutations in this tumour suppressor gene.
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206
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Chu S, Trust TJ. An Aeromonas salmonicida gene which influences a-protein expression in Escherichia coli encodes a protein containing an ATP-binding cassette and maps beside the surface array protein gene. J Bacteriol 1993; 175:3105-14. [PMID: 8491726 PMCID: PMC204632 DOI: 10.1128/jb.175.10.3105-3114.1993] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A conserved Aeromonas salmonicida gene (abcA) affecting expression of the surface array protein gene (vapA) in Escherichia coli was identified. The 924-bp gene starts 205 bp after vapA and codes for a protein with a deduced molecular weight (M(r)) of 34,015 containing an N-terminal P-loop and significant homology to the ATP-binding cassette transport protein superfamily. AbcA was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) by using T7 polymerase expression and DNA-directed translation and was copurified with the sarkosyl-soluble cytoplasmic membrane fraction. The protein displayed aberrant migration during SDS-PAGE. A lacZ fusion containing 128 bp of upstream sequence and 387 bases in the 5' end of abcA was constructed, and the beta-galactosidase activity of the abcA-lacZ fusion gene was shown to be similar in E. coli and A. salmonicida. The 130,000-M(r) AbcA-LacZ fusion protein was purified, and by using an ATP affinity column, the 129 AbcA N-terminal P-loop-containing residues were shown to bind ATP.
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207
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Choi WT, MacLean HE, Chu S, Warne GL, Zajac JD. Kennedy's disease: genetic diagnosis of an inherited form of motor neuron disease. AUSTRALIAN AND NEW ZEALAND JOURNAL OF MEDICINE 1993; 23:187-92. [PMID: 8517843 DOI: 10.1111/j.1445-5994.1993.tb01815.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Kennedy's disease (X-linked spinal and bulbar muscular atrophy) is an inherited form of motor neuron disease that may be diagnosed genetically using the polymerase chain reaction (PCR). This form of motor neuron disease principally affects the proximal limb girdle muscles as well as those involved with deglutition and phonation. Onset is usually late, in the fourth to fifth decades of life, and progression is slow. Moderate gynaecomastia and testicular atrophy are usually present, suggesting a defect in androgen receptor function. Being inherited in an X-linked recessive manner, only males are affected, with females as the unaffected carriers. The genetic abnormality that causes Kennedy's disease is an enlargement of the androgen receptor (AR) gene, which is located on the proximal long arm of the X chromosome. In patients with this disease, a region in the gene containing repeated CAG triplet nucleotides is approximately twice the size of that found in normal people. Using PCR to amplify this region of the AR gene, this study confirms this genetic mutation in 12 males from eight different families. All these families live on the east coast of Australia. This mutation was not found in five patients with other forms of motor neuron disease. Twelve heterozygote females, the daughters of affected males and carrier females, have also been identified. In addition, there are 14 asymptomatic and as yet untested sons of carriers, ranging in age from less than one year to over 40 years of age. Each has a 50% chance of inheriting the abnormal gene from his mother and thus developing Kennedy's disease.(ABSTRACT TRUNCATED AT 250 WORDS)
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208
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Gibble K, Chu S. Laser-cooled Cs frequency standard and a measurement of the frequency shift due to ultracold collisions. PHYSICAL REVIEW LETTERS 1993; 70:1771-1774. [PMID: 10053382 DOI: 10.1103/physrevlett.70.1771] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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209
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Fee MS, Mills AP, Chu S, Shaw ED, Danzmann K, Chichester RJ, Zuckerman DM. Measurement of the positronium 1(3)S1-2(3)S1 interval by continuous-wave two-photon excitation. PHYSICAL REVIEW LETTERS 1993; 70:1397-1400. [PMID: 10053282 DOI: 10.1103/physrevlett.70.1397] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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210
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MacLean HE, Chu S, Warne GL, Zajac JD. Related individuals with different androgen receptor gene deletions. J Clin Invest 1993; 91:1123-8. [PMID: 8450042 PMCID: PMC288068 DOI: 10.1172/jci116271] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We have identified different members of one family affected by androgen insensitivity syndrome who have deletions of different exons of the X-linked androgen receptor (AR) gene. Two affected (XY) siblings have a deletion of exon E of the AR gene and their affected (XY) aunt has a normal exon E, but a deletion of exons F and G of the same gene. The mother and maternal grandmother of the children both carry the exon E deletion, but not the exon F, G deletion. Both deletions are 5 kb in length and have one breakpoint within a 200-bp region in intron 5; however, they extend in opposite directions. The probability that these two different deletions have arisen at random is extremely low, but the cause of this intriguing phenomenon remains to be found.
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211
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Simmons RM, Finer JT, Warrick HM, Kralik B, Chu S, Spudich JA. Force on single actin filaments in a motility assay measured with an optical trap. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 332:331-6; discussion 336-7. [PMID: 8109348 DOI: 10.1007/978-1-4615-2872-2_32] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have used an optical trap to measure or exert a force on single actin filaments via the attachment of polystyrene beads which were coated with NEM-modified HMM. In the simplest experiment, beads were attached to rhodamine phalloidin labelled actin filaments and observed to move on an HMM coated surface in the presence of ATP. Moving beads were steered into the vicinity of the trap using a PZT operated microscope stage. The minimum force needed to stop a moving bead was measured by lowering the trap strength until the bead resumed movement. By aligning the optical trap with the centre of a quadrant detector placed in an image plane of the microscope, it was possible to measure the force exerted on a filament by measuring the displacement of the bead position from the centre of the trap. In each of these experiments, the trap was calibrated by applying a Stokes force to a bead in free solution. The characteristics of the trap were studied, and the displacement of the bead from the centre of the trap was shown to be directly proportional to the applied force over a large part of the total range of the trap. The compliance of the trap could be substantially reduced by the use of feedback control to deflect the laser beam via an acousto-optic modulator. The advantages and limitations of this technique will be discussed.
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Dasch JR, Pace DR, Avis PD, Bentz H, Chu S. Characterization of monoclonal antibodies recognizing bovine bone osteoglycin. Connect Tissue Res 1993; 30:11-21. [PMID: 7512011 DOI: 10.3109/03008209309032927] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Six monoclonal antibodies (mAb) are described that bound to the bovine bone glycoprotein, osteoglycin. The protein osteoglycin was originally called Osteoinductive Factor (OIF). The antibodies were characterized with respect to their reaction patterns in Western blots, indirect immunoprecipitation, and binding epitope. The antibodies bound to one of two sequential determinants, either residues 62-76 or 95-105, in the C-terminal region of mature osteoglycin. One mAb, 2C11, was found to be useful for affinity purification of osteoglycin. Another mAb, 3B2, was able to immunohistochemically stain osteoblasts, osteocytes, chondrocytes, occasional osteoclasts and nail bed epithelial cells in rat neonatal forelimb. The mAbs will provide an essential tool for the further characterization of this unique glycoprotein.
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213
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Warrick HM, Simmons RM, Finer JT, Uyeda TQ, Chu S, Spudich JA. In vitro methods for measuring force and velocity of the actin-myosin interaction using purified proteins. Methods Cell Biol 1993; 39:1-21. [PMID: 8246790 DOI: 10.1016/s0091-679x(08)60158-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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214
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Kasevich M, Chu S. Laser cooling below a photon recoil with three-level atoms. PHYSICAL REVIEW LETTERS 1992; 69:1741-1744. [PMID: 10046302 DOI: 10.1103/physrevlett.69.1741] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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215
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Kasevich M, Chu S. Measurement of the gravitational acceleration of an atom with a light-pulse atom interferometer. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/bf00325375] [Citation(s) in RCA: 255] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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216
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Gibble KE, Kasapi S, Chu S. Improved magneto-optic trapping in a vapor cell. OPTICS LETTERS 1992; 17:526-528. [PMID: 19794547 DOI: 10.1364/ol.17.000526] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have captured 3.6 x 10(10) cesium atoms in a magneto-optic trap loaded from a vapor cell. The 300-fold increase in the number of trapped atoms compared with that of previous research was accomplished by using larger laser intensities and 4-cm-diameter laser beams. The loading time constant was as short as 0.2 s.
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217
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Fee MS, Danzmann K, Chu S. Optical heterodyne measurement of pulsed lasers: Toward high-precision pulsed spectroscopy. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 45:4911-4924. [PMID: 9907574 DOI: 10.1103/physreva.45.4911] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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218
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Chu S, Park Y, Locke C, Wilson DS, Cavanaugh JC. Drug-food interaction potential of clarithromycin, a new macrolide antimicrobial. J Clin Pharmacol 1992; 32:32-6. [PMID: 1531484 DOI: 10.1002/j.1552-4604.1992.tb03784.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To evaluate the effect of food on bioavailability, clarithromycin and 14-hydroxyclarithromycin (active metabolite) pharmacokinetics were assessed in 26 healthy adult volunteers after ingestion of a single oral 500-mg dose of clarithromycin in a fasting state (2 hours before breakfast after an overnight fast) and a nonfasting state (0.5 hours after the start of breakfast). Clarithromycin and 14-hydroxy metabolite plasma concentrations were measured using a high-performance liquid chromatographic technique. Food intake immediately before dosing increased the extent of absorption from the 500-mg tablet formulation by approximately 25%. The mean increase in metabolite area under the plasma concentration-time curve was approximately 9%. These results suggest that clarithromycin can be taken without regard to timing in relation to meals.
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219
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Moler K, Weiss DS, Kasevich M, Chu S. Theoretical analysis of velocity-selective Raman transitions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 45:342-348. [PMID: 9906732 DOI: 10.1103/physreva.45.342] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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220
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Keefe J, Wauk L, Chu S, DeLustro F. Clinical use of injectable bovine collagen: a decade of experience. CLINICAL MATERIALS 1991; 9:155-62. [PMID: 10171198 DOI: 10.1016/0267-6605(92)90095-b] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Bovine collagen has long been recognized as a safe, highly biocompatible material. In 1981 and 1985, two injectable fibrillar suspensions of purified bovine dermal collagen, Zyderm and Zyplast collagen implant, were commercially launched in the USA for use in soft tissue contour irregularities. Since that time more than 750 000 patients have been treated with Zyderm and/or Zyplast collagen implants internationally. Adverse reactions to bovine collagen implants occur in a small percentage of treated patients. The most prevalent adverse reaction is localized hypersensitivity at treatment sites, occurring in 3% of skin tested patients and 1 to 2% of the treated patients. These reactions resolve with time as the implant material is resorbed by the host. Circulating antibodies to bovine collagen can be demonstrated in the sera of a majority of patients (90-100%) with local hypersensitivity. These antibodies are specific for bovine collagen and do not cross react with human type I, II or III collagen. Although the presence of a humoral immune response to bovine collagen can be associated with localized symptoms of hypersensitivity, antibodies to bovine collagen can also be demonstrated in the absence of any clinical manifestation.
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221
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Chu S, Cavaignac S, Feutrier J, Phipps BM, Kostrzynska M, Kay WW, Trust TJ. Structure of the tetragonal surface virulence array protein and gene of Aeromonas salmonicida. J Biol Chem 1991; 266:15258-65. [PMID: 1869553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The paracrystalline surface protein array of the pathogenic bacterium Aeromonas salmonicida is a primary virulence factor with novel binding capabilities. The species-specific structural gene (vapA) for this array protein (A-protein) was cloned into lambda gt11 but was unstable when expressed in Escherichia coli, undergoing an 816-base pair deletion due to a 21-base pair direct repeat within the gene. However, the gene was stable in cosmid pLA2917 as long as expression was poor. A-protein was located in the cytoplasmic, inner membrane and periplasmic fractions in E. coli. The DNA sequence revealed a 1,506-base pair open reading frame encoding a protein consisting of a 21-amino acid signal peptide, and a 481-residue 50,778 molecular weight protein containing considerable secondary structure. When assembled into a paracrystalline protein array on Aeromonas the cell surface A-protein was totally refractile to cleavage by trypsin, but became trypsin sensitive when disassembled. Trypsin cleavage of the isolated protein provided evidence that both the NH2- and COOH-terminal regions form distinct structural domains, consistent with three-dimensional ultrastructural evidence. The NH2-terminal 274-residue domain remained refractile to trypsin activity. This segment connects by a trypsin and CNBr-sensitive 78-residue linker region to a COOH-terminal 129-residue fragment which could apparently refold into a partially trypsin-resistant structure after cleavage at residue 323.
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222
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Kasevich M, Chu S. Atomic interferometry using stimulated Raman transitions. PHYSICAL REVIEW LETTERS 1991; 67:181-184. [PMID: 10044515 DOI: 10.1103/physrevlett.67.181] [Citation(s) in RCA: 257] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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223
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Fee MS, Mills AP, Shaw ED, Chichester RJ, Zuckerman DM, Chu S, Danzmann K. Sensitive detection of Doppler-free two-photon-excited 2S positronium by spatially separated photoionization. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:R5-R8. [PMID: 9905741 DOI: 10.1103/physreva.44.r5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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224
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Kasevich M, Weiss DS, Riis E, Moler K, Kasapi S, Chu S. Atomic velocity selection using stimulated Raman transitions. PHYSICAL REVIEW LETTERS 1991; 66:2297-2300. [PMID: 10043449 DOI: 10.1103/physrevlett.66.2297] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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225
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Kasevich MA, Weiss DS, Chu S. Normal-incidence reflection of slow atoms from an optical evanescent wave. OPTICS LETTERS 1990; 15:607. [PMID: 19768022 DOI: 10.1364/ol.15.000607] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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