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Walter P, Grosse J, Bihr AM, Kramer G, Schulz HU, Schwantes U, Stöhrer M. Bioavailability of trospium chloride after intravesical instillation in patients with neurogenic lower urinary tract dysfunction: A pilot study. Neurourol Urodyn 1999; 18:447-53. [PMID: 10494116 DOI: 10.1002/(sici)1520-6777(1999)18:5<447::aid-nau6>3.0.co;2-q] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Oral drug treatment of detrusor overactivity often causes undesirable side effects in other organs. For some patients, in particular those with neurogenically induced detrusor overactivity (detrusor hyperreflexia), the tolerance level for adverse effects is low and oral treatment may become ineffective. Intravesical administration of the drug can diminish the side effects or increase treatment effectivity in patients who are (partially) refractory to oral treatment because the relative concentration of the drug is increased in the target organ and decreased in the circulation. Six men (19-34 years old) with traumatic spinal cord lesions between C2 and Th11 were randomized to intravesical instillation with 15 or 30 mg trospium chloride in 40 ml saline into the empty bladder. Catheterization was postponed until at least 3 h after instillation, and fluid intake was not allowed during the first 4 h. Blood samples were taken before and 11 times after instillation; the last sample 12 h post instillation. Four positive samples were found in three patients: 0.10 ng/ml after 1 h and 0.13 ng/ml after 2(1/2) h in two patients with 15 mg, and 0.24 ng/ml after 30 min and 0.70 ng/ml after 6 h in one patient with 30 mg instilled trospium chloride. Three adverse effects were reported and were rated as probably not related to the drug. It is concluded that intravesically instilled trospium chloride is not absorbed into the circulation in significant amounts and, thus, it may be expected that this mode of administration will improve the efficacy of trospium chloride therapy by reducing the side effects. Neurourol. Urodynam. 18:447-453, 1999.
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Abstract
BACKGROUND Benign prostatic hyperplasia (BPH) is mainly a stromal process, showing an increased ratio of stromal to epithelial elements, a collagen type III downregulation, and a collagen types I and IV upregulation. Little is known about elastin gene expression in BPH tissues due to difficulties related to extensive alternative splicing of the elastin gene. Therefore, we analyzed and quantified elastin gene expression in BPH. METHODS A competitive reverse transcriptase-polymerase chain reaction (competitive RT-PCR) quantitative technique was used, and a quantitative elastin mRNA analysis with normal (n = 10) and BPH (n = 12) tissues was performed with two newly designed elastin primers. Small tissue samples (4-8 mg) were homogenized and sonicated, and cDNA was synthesized from mRNA using a RT reaction. Various target (wild-type) elastin cDNAs with unknown concentrations were competitively coamplified with known serial dilutions of the control mutant template, differing from the target cDNA by a short deletion. Gel fractions and computerized densitometry, were performed and cDNA concentration was calculated by linear regression. RESULTS The primers identified in our study (BOB-1 and BOB-2) accurately amplified a consistent length of the elastin cDNA, avoiding areas of alternative splicing. The average elastin mRNA concentration in BPH tissues was 53 attomole/mg +/- 11.6 vs. 140.6 attomole/mg +/- 19.6 in normal prostatic tissue (P = 0.019). The variation within every sample was less than 10%. CONCLUSIONS Our observations suggest a significant downregulation (70%) of the elastin mRNA gene in the transition zone of BPH patients.
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Ariese F, Cofino W, Gómez-Ariza JL, Kramer G, Quevauviller P. Evaluation of the state-of-the-art of butyl- and phenyltin compound determinations in freshwater sediment prior to certification of a reference material. JOURNAL OF ENVIRONMENTAL MONITORING : JEM 1999; 1:191-6. [PMID: 11529099 DOI: 10.1039/a807886f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In order to control the quality of butyl- and phenyltin compound determinations in sediment, the Standards, Measurements and Testing Programme (formerly BCR) of the European Commission has started a project, the final aim of which is to certify a freshwater sediment for its contents of a range of organotin compounds (mono-, di- and tributyltin, and mono-, di- and triphenyltin). The first part of this project involved an interlaboratory study which aimed to test the feasibility of preparation of candidate freshwater sediment reference material and to detect and remove most of the pitfalls observed in organotin determinations. This paper presents the main results of this interlaboratory study carried out prior to the certification campaign. The agreement obtained among laboratories for the six compounds determined was considered to reflect the state-of-the-art and was encouraging enough to decide upon the organisation of a certification campaign, which will be concluded in June 1999.
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Tsalkova T, Kramer G, Hardesty B. The effect of a hydrophobic N-terminal probe on translational pausing of chloramphenicol acetyl transferase and rhodanese. J Mol Biol 1999; 286:71-81. [PMID: 9931250 DOI: 10.1006/jmbi.1998.2481] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect on translational pausing of a hydrophobic probe, coumarin, at the N terminus of nascent peptides was investigated. Two different proteins, bacterial chloramphenicol acetyltransferase and bovine rhodanese, were synthesized by coupled transcription/translation in a cell-free system derived from Escherichia coli. Protein synthesis was initiated with N-formyl-Met-tRNAf or N-acetyl-S-coumarin-Met-tRNAf. Cotranslational incorporation of the coumarin derivative generated nascent polypeptides with a hydrophobic residue at their N termini. The effect of the two N-terminal groups on the size distribution and quantity of the peptides formed by translational pausing was investigated. The N-terminal coumarin caused an accumulation of nascent chloramphenicol acetyltransferase peptides in the mass range of 3.5-4.0 kDa that reflects a delay in translation at this point. No similar effect on rhodanese pause-site peptides was observed. This effect on translational pausing cannot be explained by either mRNA secondary structure or rare codons and tRNA abundance. It is suggested that the effect of N-terminal coumarin on translational pausing is the result of the interaction of the nascent peptide with components of the large ribosomal subunit along the path it follows between the peptidyl transferase center and the exit site on the distal surface.
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Abstract
Nascent proteins appear to fold co-translationally. The ribosome itself may function as a chaperone, providing a sheltered environment in which the nascent peptide is protected from aggregation and degradation, and in which folding into the tertiary structure is facilitated by interactions both with ribosomal proteins and with specific segments of the ribosomal RNA.
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Kramer G, Weiss V. Functional dissection of the transmitter module of the histidine kinase NtrB in Escherichia coli. Proc Natl Acad Sci U S A 1999; 96:604-9. [PMID: 9892680 PMCID: PMC15183 DOI: 10.1073/pnas.96.2.604] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Signal transduction by two-component systems involves phosphorylation and thereby activation of the response regulator by the cognate histidine kinase. Bifunctional histidine kinases have two opposing activities: depending on the environmental stimuli they either promote phosphorylation or stimulate the rapid dephosphorylation of the response regulator. To determine the mechanism of this switch, we analyzed the domain organization of the bifunctional histidine kinase NtrB. Based on sequence alignments with other histidine kinases and a deletion analysis, we defined three separate subdomains of the transmitter module, the H domain (amino acids 123-221), the N domain (amino acids 221-269), and the G domain (amino acids 269-349). The transmitter module, when separately expressed, exhibited a constitutive positive phenotype. In contrast, in the absence of the G domain, the H domain exhibits a constitutive negative phenotype. This negative regulatory activity of the H domain is inhibited by the G domain. The G domain could be physically uncoupled; when coexpressed with the H-N fragment, the constitutive positive phenotype of the transmitter was restored. We demonstrate, in vitro, that the constitutive negative phenotype of the fragments lacking the G domain is caused by stimulation of dephosphorylation of the response regulator NtrC-P. Based on our analysis, we suggest that the function of the sensor domain is to control the interaction of the H and G domains. If these subdomains interact, NtrB acts as a positive regulator; if they cannot interact, NtrB acts as a negative regulator.
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Stöhrer M, Goepel M, Kramer G, Löchner-Ernst D, Rübben H. [Detrusor myectomy (autoaugmentation) in the treatment of hyper-reflexive low compliance bladder]. Urologe A 1999; 38:30-7. [PMID: 10081098 DOI: 10.1007/s001200050241] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
After unsuccessful medical treatment of a neurogenic hyperreflexive bladder dysfunction further treatment options are the ileal bladder augmentation, the detrusor-myectomy (bladder auto-augmentation) and the sacral root deafferentation. All techniques lead to a low-pressure bladder with enlarged storage volume. The authors here report about their personal experience with the detrusor myectomy in 62 patients with hyperreflexive neurogenic bladder dysfunction from 1989 until 1998. Indication, surgical technique, and long-time results are presented.
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Kramer G, Kudlicki W, McCarthy D, Tsalkova T, Simmons D, Hardesty B. N-terminal and C-terminal modifications affect folding, release from the ribosomes and stability of in vitro synthesized proteins. Int J Biochem Cell Biol 1999; 31:231-41. [PMID: 10216956 DOI: 10.1016/s1357-2725(98)00143-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Important aspects of translation are release and folding of the synthesized protein into its three-dimensional structure. Studies from our group indicated that during in vitro protein synthesis a large portion of full-length polypeptides apparently accumulated as peptidyl-tRNA on ribosomes. We have also shown that some proteins though released in biologically active form may be inactivated without being degraded. These experiments were carried out by coupled transcription/translation using an Escherichia coli extract in which eukaryotic or prokaryotic test proteins were synthesized from their coding sequence inserted into specific plasmids. Experiments described here were designed to analyze the effects of N-terminal and C-terminal modifications of the coding sequence on the ribosomal release/termination process and on the stability of the newly synthesized protein. Elimination of the leader sequence in two proteins tested, mitichondrial rhodanese and bacterial beta-lactamase, caused an increase in the percentage of polypeptides released from the ribosomes relative to total synthesis. Conversely, an N-terminal extension such as a histidine-lag impaired the ribosomal release process. Also, a hydrophobic N-terminal modification of the synthesized protein reduced release of newly formed protein from the ribosomes. A C-terminal extension of the coding sequence for rhodanese by one amino acid decreased the percentage released polypeptide and furthermore affected the stability of the in vitro formed protein. We propose that a regulatory mechanism exists by which N-terminal and C-terminal sequences of a newly synthesized protein have feed-back effects on the termination factor-mediated release and on the stability of the native three-dimensional structure.
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Kramer G, Estel K, Schmitt FJ, Jacobasch HJ. Laterally Resolved Measurement of Interaction Forces between Surfaces That Are Partly Covered with Polyelectrolytes. J Colloid Interface Sci 1998; 208:302-309. [PMID: 9820778 DOI: 10.1006/jcis.1998.5837] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The adsorption of polycation poly(diallyldimethylammonium chloride), PDADMAC for short, on oxidized silicon wafers is investigated by direct force measurements using an atomic force microscope. It is shown that the electrostatic forces as well as the adhesive properties are significantly influenced by adsorbed PDADMAC. By using force mapping and monitoring the increased adhesion between the surfaces the adsorbed polymer can be two-dimensionally monitored on the surface. Different coverages of the polycation were investigated, which qualitatively agree well with results of XPS and electrokinetic measurements. Copyright 1998 Academic Press.
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Madersbacher S, Gröbl M, Kramer G, Dirnhofer S, Steiner GE, Marberger M. Regulation of heat shock protein 27 expression of prostatic cells in response to heat treatment. Prostate 1998; 37:174-81. [PMID: 9792134 DOI: 10.1002/(sici)1097-0045(19981101)37:3<174::aid-pros6>3.0.co;2-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The clinical value of heat-induced coagulation of prostatic tissue is evaluated as a minimally invasive treatment for patients with benign prostatic hyperplasia (BPH) and, more recently, localized prostate cancer (PC). To obtain a more detailed insight on the effect of heat on prostatic cells, heat shock protein (HSP) 27 expression of normal and malignant prostatic cells was studied. METHODS In vitro, HSP27 expression of prostatic stromal cells and the human prostate cancer cell line LNCaP was studied by Western blotting when cultured at 37 degrees C. Subsequently, the effect of a sublethal heat shock from 43-49 degrees C for 60 min on HSP27 expression of LNCaP was determined. In vivo, HSP27 expression pattern of nine human prostates, which were treated in vivo by thermoablation with transrectal high-intensity focused ultrasound (HIFU) 3 hr-8 days prior to surgical removal, was analyzed by immunohistochemistry. Untreated BPH (n = 10) and PC (n = 7) specimens served as controls. RESULTS Under physiologic conditions (37 degrees C), LNCaP and prostatic stromal cells expressed a 27-kD and 56-kD anti-HSP27 reactive molecule. Following sublethal cell heating, HSP27 (27 kD) expression of LNCaP increased by 3-4-fold in a temperature-dependent manner. In untreated BPH specimens (n = 10), muscle cells stained HSP27-positive in all samples, while epithelial cells (EC) were negative in 6 out of 10 specimens. At the border of the high-intensity focused ultrasound (HIFU) necrosis, increased HSP27 expression was consistently demonstrable (n = 9). HSP27 upregulation was strongest 2-3 hr after HIFU but still demonstrable after 5-8 days. In this border zone, basal and secretory EC as well as muscle cells stained strongly for HSP27. CONCLUSIONS Benign and malignant human prostatic cells respond to heat by increased expression of HSP27 in vitro and in vivo. Transrectal HIFU therapy induces intraprostatic thermonecrosis surrounded by a zone characterized by a massive upregulation of HSP27 expression.
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Trevino RJ, Tsalkova T, Kramer G, Hardesty B, Chirgwin JM, Horowitz PM. Truncations at the NH2 terminus of rhodanese destabilize the enzyme and decrease its heterologous expression. J Biol Chem 1998; 273:27841-7. [PMID: 9774394 DOI: 10.1074/jbc.273.43.27841] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rhodanese mutants containing sequential NH2-terminal deletions were constructed to test the distinct contributions of this region of the protein to expression, folding, and stability. The results indicate that the first 11 residues are nonessential for folding to the active conformation, but they are necessary for attaining an active, stable structure when expressed in Escherichia coli. Rhodanese species with up to 9 residues deleted were expressed and purified. Kinetic parameters for the mutants were similar to those of the full-length enzyme. Compared with shorter truncations, mutants missing 7 or 9 residues were (a) increasingly inactivated by urea denaturation, (b) more susceptible to inactivation by dithiothreitol, (c) less able to be reactivated, and (d) less rapidly inactivated by incubation at 37 degreesC. Immunoprecipitation showed that mutants lacking 10-23 NH2-terminal amino acids were expressed as inactive species of the expected size but were rapidly eliminated. Cell-free transcription/translation at 37 degreesC showed mutants deleted through residue 9 were enzymatically active, but they were inactive when deleted further, just as in vivo. However, at 30 degreesC in vitro, both Delta1-10 and Delta1-11 showed considerable activity. Truncations in the NH2 terminus affect the chemical stability of the distantly located active site. Residues Ser-11 through Gly-22, which form the NH2-proximal alpha-helix, contribute to folding to an active conformation, to resisting degradation during heterologous expression, and to chemical stability in vitro.
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Kramer G, Kudlicki W, Hardesty B. In vitro engineering using synthetic tRNAs with altered anticodons including four-nucleotide anticodons. Methods Mol Biol 1998; 77:105-16. [PMID: 9770664 DOI: 10.1385/0-89603-397-x:105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Kashani M, Steiner G, Haitel A, Schaufler K, Thalhammer T, Amann G, Kramer G, Marberger M, Schöller A. Expression of the aryl hydrocarbon receptor (AhR) and the aryl hydrocarbon receptor nuclear translocator (ARNT) in fetal, benign hyperplastic, and malignant prostate. Prostate 1998. [PMID: 9759704 DOI: 10.1002/(sici)1097-0045(19981001)37:] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Androgen-dependent tissue has been reported to be affected by chemical ligands of the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, which heterodimerizes with the aryl hydrocarbon receptor nuclear translocator protein (ARNT). METHODS Fetal (n = 3), benign hyperplastic (BPH) (n = 10), and carcinomatous (CaP) (n = 19) prostate tissues were analyzed using immunohistochemistry. Western blot analysis was used to confirm the identity of the recognized proteins. RESULTS Immunoblotting of enriched prostatic epithelial cells (EC) and stromal cells revealed constitutive expression of bands at around 110 kDa and 90 kDa, using anti-AhR and anti-ARNT, respectively. Immunohistology of the fetal specimens revealed heterogeneous cytoplasmic and nuclear AhR expression of immature EC and mesenchymal cells. Constitutive expression of AhR (primarily cytoplasmic) and ARNT (nuclear and cytoplasmic) by the majority of adult basal and secretory EC, CaP, and smooth muscle cells was confirmed in situ. The most intense anti-AhR/-ARNT reactivity was found on smooth muscle cells, followed by EC and fibrocytes. Secretory BPH-EC revealed significantly decreased AhR expression when compared to normal tissue segments. By contrast, anti-AhR reactivity was frequently increased in the more dedifferentiated tumor areas. CONCLUSIONS These findings suggest that an undefined physiologic AhR ligand(s) as well as environmental factors may exert effects on EC and smooth muscle cells in the prostate through binding to these receptors.
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Kashani M, Steiner G, Haitel A, Schaufler K, Thalhammer T, Amann G, Kramer G, Marberger M, Schöller A. Expression of the aryl hydrocarbon receptor (AhR) and the aryl hydrocarbon receptor nuclear translocator (ARNT) in fetal, benign hyperplastic, and malignant prostate. Prostate 1998; 37:98-108. [PMID: 9759704 DOI: 10.1002/(sici)1097-0045(19981001)37:2<98::aid-pros6>3.0.co;2-h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Androgen-dependent tissue has been reported to be affected by chemical ligands of the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, which heterodimerizes with the aryl hydrocarbon receptor nuclear translocator protein (ARNT). METHODS Fetal (n = 3), benign hyperplastic (BPH) (n = 10), and carcinomatous (CaP) (n = 19) prostate tissues were analyzed using immunohistochemistry. Western blot analysis was used to confirm the identity of the recognized proteins. RESULTS Immunoblotting of enriched prostatic epithelial cells (EC) and stromal cells revealed constitutive expression of bands at around 110 kDa and 90 kDa, using anti-AhR and anti-ARNT, respectively. Immunohistology of the fetal specimens revealed heterogeneous cytoplasmic and nuclear AhR expression of immature EC and mesenchymal cells. Constitutive expression of AhR (primarily cytoplasmic) and ARNT (nuclear and cytoplasmic) by the majority of adult basal and secretory EC, CaP, and smooth muscle cells was confirmed in situ. The most intense anti-AhR/-ARNT reactivity was found on smooth muscle cells, followed by EC and fibrocytes. Secretory BPH-EC revealed significantly decreased AhR expression when compared to normal tissue segments. By contrast, anti-AhR reactivity was frequently increased in the more dedifferentiated tumor areas. CONCLUSIONS These findings suggest that an undefined physiologic AhR ligand(s) as well as environmental factors may exert effects on EC and smooth muscle cells in the prostate through binding to these receptors.
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Jatoi A, Daly BD, Kramer G, Mason JB. A cross-sectional study of vitamin intake in postoperative non-small cell lung cancer patients. J Surg Oncol 1998; 68:231-6. [PMID: 9721708 DOI: 10.1002/(sici)1096-9098(199808)68:4<231::aid-jso5>3.0.co;2-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND AND OBJECTIVES This cross-sectional study of postoperative non-small cell lung cancer (NSCLC) patients examined possible effects of vitamin intake and folate status on disease-free survival. METHODS Supplemental vitamin usage, dietary vitamin intake (Willett Food Frequency Questionnaire), red blood cell (RBC) folate, and serum folate concentrations were assessed in patients with a history of NSCLC. Exclusion criteria included factors that alter folate status or that are associated with altered nutritional habits: (1) evidence of cancer on history, physical, or chest radiograph; (2) tobacco, alcohol ingestion (>2 drinks/ day), or cancer treatment within 3 months; (3) use of folate antagonists; and (4) age <60 years. RESULTS 36 subjects were evaluated. The median disease-free censored survival was 24 months (range 4-41). Nineteen of 36 patients (53%) reported vitamin supplementation. Vitamin users had a longer median censored survival compared with nonusers (41 months versus 11 months; P = 0.002). With adjustment for cancer stage, the association between RBC folate and censored survival (r = 0.35; P = 0.055) and between serum folate and censored survival (r = 0.32; P = 0.083) approached statistical significance. CONCLUSIONS NSCLC patients who took vitamin supplements were more likely to be long-term survivors in the patients studied; a similar trend toward long-term survival was seen among patients with higher circulating folate concentrations.
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Tsalkova T, Odom OW, Kramer G, Hardesty B. Different conformations of nascent peptides on ribosomes. J Mol Biol 1998; 278:713-23. [PMID: 9614937 DOI: 10.1006/jmbi.1998.1721] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The length at which the N terminus of nascent proteins becomes available to antibodies during their synthesis on ribosomes was determined. Three different proteins, bovine rhodanese, bacterial chloramphenicol acetyltransferase and MS2 coat protein, were synthesized with coumarin at their N terminus in a cell-free system derived from Escherichia coli. A derivative of coumarin was cotranslationally incorporated as N-coumarin-methionine at the N terminus of polypeptides. The interaction of specific anti-coumarin antibodies with this N-terminal coumarin of ribosome-bound nascent peptides was examined. The results indicate that short nascent peptides of each of the three proteins are unreactive, that the length at which they become accessible to the antibodies is different for the three proteins, and that longer peptides differ in their reactivity. It is suggested that these differences are due to differences in the conformation acquired by the peptides as they are synthesized on the ribosomes.
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McCarthy D, Kramer G, Hardesty B. Reactivation of thermally inactivated pre-beta-lactamase by DnaK, DnaJ, and GrpE. Protein Sci 1998; 7:1164-71. [PMID: 9605320 PMCID: PMC2144002 DOI: 10.1002/pro.5560070510] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To understand the role of the 23-amino acid signal sequence in the folding and stability of beta-lactamase, the precursor and a mutant beta-lactamase with a 19-amino acid signal sequence deletion were synthesized in vitro using an Escherichia coli cell-free coupled transcription/translation system. Approximately 30% of the newly synthesized full-length precursor and 60% of the deletion mutant polypeptides were terminated and released from the ribosomes as active enzyme. Activity of the pre-beta-lactamase, but not the mutant, was unstable at 37 degrees C, suggesting that the signal sequence causes the enzyme to unfold. This inactivation was independent of ATP. Pre-beta-lactamase activity was stabilized by lowering the temperature to 30 degrees C. Furthermore, addition of the molecular chaperones DnaK/J and GrpE, in the presence of ATP and Mg2+, restored the activity of the temperature-inactivated precursor. The precursor formed a stable complex with DnaK and GrpE. Both ATP and DnaJ were required for recovery of enzymatic activity, indicating that DnaJ may bind transiently to the complex. These results suggest that the signal sequence of the pre-beta-lactamase causes a temperature-dependent unfolding of the synthesized enzyme and that DnaK/J and GrpE interact with unfolded pre-beta-lactamase to promote refolding of the protein into its native, enzymatically active conformation.
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Kramer G, Zhang T, Kudlicki W, Hardesty B. Preparation and application of chaperone-deficient Escherichia coli cell-free translation systems. Methods Enzymol 1998; 290:18-26. [PMID: 9534148 DOI: 10.1016/s0076-6879(98)90004-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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219
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Primus G, Kramer G, Pummer K. Restoration of Micturition in Patients With Acontractile and Hypocontractile Detrusor by Transurethral Electrical Bladder Stimulation. J Urol 1998. [DOI: 10.1016/s0022-5347(01)63871-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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220
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Kudlicki W, Coffman A, Kramer G, Hardesty B. Renaturation of rhodanese by translational elongation factor (EF) Tu. Protein refolding by EF-Tu flexing. J Biol Chem 1997; 272:32206-10. [PMID: 9405422 DOI: 10.1074/jbc.272.51.32206] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The translation elongation factor (EF) Tu has chaperone-like capacity to promote renaturation of denatured rhodanese. This renaturation activity is greatly increased under conditions in which the factor can oscillate between the open and closed conformations that are induced by GDP and GTP, respectively. Oscillation occurs during GTP hydrolysis and subsequent replacement of GDP by EF-Ts which is then displaced by GTP. Renaturation of rhodanese and GTP hydrolysis by EF-Tu are greatly enhanced by the guanine nucleotide exchange factor EF-Ts. However, renaturation is reduced under conditions that stabilize EF-Tu in either the open or closed conformation. Both GDP and the nonhydrolyzable analog of GTP, GMP-PCP, inhibit renaturation. Kirromycin and pulvomycin, antibiotics that specifically bind to EF-Tu and inhibit its activity in peptide elongation, also strongly inhibit EF-Tu-mediated renaturation of denatured rhodanese to levels near those observed for spontaneous, unassisted refolding. Kirromycin locks EF-Tu in the open conformation in the presence of either GTP or GDP, whereas pulvomycin locks the factor in the closed conformation. The results lead to the conclusion that flexing of EF-Tu, especially as occurs between its open and closed conformations, is a major factor in its chaperone-like refolding activity.
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Kniehl B, Kramer G, Spira M. Large- $p_T$ photoproduction of $D^{*\pm}$ mesons in $ep$ collisions. ACTA ACUST UNITED AC 1997. [DOI: 10.1007/s002880050591] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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222
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Quastel MR, Goldsmith JR, Cwikel J, Merkin L, Wishkerman VY, Poljak S, Abdelgani A, Kordysh E, Douvdevani A, Levy J, Gorodisher R, Barki Y, Emerit I, Kramer G. Lessons learned from the study of immigrants to Israel from areas of Russia, Belarus, and Ukraine contaminated by the Chernobyl accident. ENVIRONMENTAL HEALTH PERSPECTIVES 1997; 105 Suppl 6:1523-1527. [PMID: 9467076 PMCID: PMC1469938 DOI: 10.1289/ehp.97105s61523] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
During the past 6 years, immigration to Israel of 700,000 persons from the former Soviet Union (FSU) included about 140,000 from radiocontaminated regions of Belarus, Ukraine, and Russia near Chernobyl. In Beer Sheva, a major center for immigrant absorption in Israel, a primary objective was to evaluate their health status and to refer them for care. 137Cs levels in 1228 men, women, and children were measured with a portable whole-body counter. Whole-body counts showed clear correlation with the degree of 137Cs ground contamination in previous regions of residence. The population could thus be sub-divided according to degree of exposure, based on previous regions of residence. The thyroid status of 300 local immigrant children was evaluated because of the increased risk of childhood thyroid cancer in the regions from which they came. This group was subdivided into comparative groups of children who came from less and more contaminated areas according to the International Atomic Energy Agency soil 137Cs contamination maps. Enlarged thyroids were found in about 40% of both groups. One 12-year-old girl from Gomel had a malignant papillary carcinoma. Thyroid-stimulating hormone levels, though within normal limits, were significantly greater (p < 0.02) for girls from high exposure regions. Liquidators showed significant increases in serum clastogenic factor and in the number of circulating glycophorin A-mutated red cells. In studies of over 700 people from both radiocontaminated and unaffected regions of the FSU, evidence for posttraumatic stress disorder was found more frequently in persons coming from the more contaminated areas.
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Kramer G, Steiner GE, Madersbacher S, Stulnig T, Lang T, Marberger M. Serial tissue polypeptide specific antigen determination in the followup of hormone treated carcinoma of the prostate. J Urol 1997; 158:1446-51. [PMID: 9302140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE We determined the impact of serum cytokeratin-18-related tissue polypeptide specific antigen (TPS) in monitoring hormone treated carcinoma of the prostate. MATERIALS AND METHODS From 1991 to 1996, serial TPS and prostate specific antigen (PSA) determinations (3,882) in 443 hormone treated prostate carcinoma patients were correlated with the clinical course for a mean of 22 months. RESULTS Elevated TPS levels were significantly associated with disease progression in hormone treated stage M1 carcinoma of the prostate (p = 0.001), even in high grade, PSA negative tumors. Post-therapy TPS declines following second line therapy in hormone refractory prostate cancer patients (92) correlated significantly with subjective response (p = 0.001, PSA p = 0.02) and progression-free survival time (r(s) = -0.76, PSA r(s) = -0.32). A TPS decrease of more than 50% coincided with palliation in 90% of patients (PSA 64%) and predicted the best chance of a longer progression of free survival (p < 0.00005, PSA p = 0.036). Vice versa, rising TPS levels (more than 20%) coincided with subjective response in only 1 of 37 patients (PSA 9 of 33). CONCLUSIONS TPS may be a useful adjunct to PSA in monitoring hormone refractory, metastasized prostate cancer.
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Kramer G, Steiner G, Madersbacher S, Stulnig T, Lang T, Marberger M. SERIAL TISSUE POLYPEPTIDE SPECIFIC ANTIGEN DETERMINATIONS IN THE FOLLOWUP OF HORMONE TREATED CARCINOMA OF THE PROSTATE. J Urol 1997. [DOI: 10.1016/s0022-5347(01)64239-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Kramer G, Buchhammer HM, Lunkwitz K. Surface modification by polyelectrolyte complexes: Influence of modification procedure, polyelectrolyte components, and substrates. J Appl Polym Sci 1997. [DOI: 10.1002/(sici)1097-4628(19970705)65:1<41::aid-app6>3.0.co;2-q] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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