451
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Gross M, Pfeiffer M, Martini M, Campbell D, Slavin J, Potter J. The quantitation of metabolites of quercetin flavonols in human urine. Cancer Epidemiol Biomarkers Prev 1996; 5:711-20. [PMID: 8877063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The flavonoid quercetin, or its metabolites, inhibit chemical carcinogenesis in rodents and may have a role in the prevention of human cancers. Quercetin exposure in human populations results from the dietary intake of various plant foods; high concentrations of quercetin are found in apples, onions, tea, and red wine. Determination of the relationship between dietary intake and cancer risk depends on the characterization of quercetin intake. The development and use of biomarkers for quercetin intake may provide a basis for the objective classification of this exposure. One possible biomarker is metabolic products of quercetin. We report the development of a high-performance liquid chromatography (HPLC)-based assay for quantitation of quercetin metabolites in human urine. The metabolites include 3,4-dihydroxyphenylacetic acid (homoprotocatechuic acid), metahydroxyphenylacetic acid, and 4-hydroxy-3-methoxyphenylacetic acid (homovanillic acid). The assay has only two major steps, ether extraction and HPLC analysis, and is suitable for analysis of large sample numbers. Analytical characteristics of the assay include a sensitivity of less than 1 microgram, precision with coefficients of variation < 10%, and metabolite recoveries > 90%. The mean concentrations of 3,4-dihydroxyphenylacetic acid, metahydroxyphenylacetic acid, and homovanillic acid in two human urine samples are approximately 0.7, 4.8, and 2.8 micrograms/ml, respectively. The identification of each metabolite is confirmed by HPLC, UV absorbance scans, and gas chromatography-mass spectrometry analysis. These results verify the occurrence of quercetin metabolites in human urine and the feasibility of quercetin metabolite quantitation, by the assay described herein, for epidemiological studies. Development of the analytical procedure is an essential first step for validation of the metabolites as biomarkers of quercetin intake.
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452
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Heppner DG, Gordon DM, Gross M, Wellde B, Leitner W, Krzych U, Schneider I, Wirtz RA, Richards RL, Trofa A, Hall T, Sadoff JC, Boerger P, Alving CR, Sylvester DR, Porter TG, Ballou WR. Safety, immunogenicity, and efficacy of Plasmodium falciparum repeatless circumsporozoite protein vaccine encapsulated in liposomes. J Infect Dis 1996; 174:361-6. [PMID: 8699067 DOI: 10.1093/infdis/174.2.361] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Seventeen malaria-naive volunteers received a recombinant Plasmodium falciparum vaccine (RLF) containing the carboxy- and the amino-terminal of the circumsporozoite protein (CSP) antigen without the central tetrapeptide repeats. The vaccine was formulated in liposomes with either a low or high dose of 3-deacylated monophosphoryl lipid A (MPL) and administered with alum by intramuscular injection. Both formulations were well tolerated and immunogenic. MPL increased sporozoite antibody titers measured by ELISA, Western blot, and immunofluorescence assay. One high-dose MPL vaccine formulation recipient developed a CSP-specific cytotoxic T lymphocyte response. After homologous sporozoite challenge, immunized volunteers developed patent malaria. There was no correlation between prepatent period and antibody titers to the amino- or carboxy-terminal. The absence of delay in patency argues against inclusion of the amino-terminal in future vaccines. A significant cytotoxic T lymphocyte response may have been suppressed by the inclusion of alum as an adjuvant.
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MESH Headings
- Adolescent
- Adult
- Antigens, Protozoan/adverse effects
- Antigens, Protozoan/immunology
- Antigens, Protozoan/therapeutic use
- Cytotoxicity, Immunologic
- Dose-Response Relationship, Drug
- Drug Carriers
- Female
- Humans
- Liposomes
- Lymphocyte Activation
- Malaria Vaccines/adverse effects
- Malaria Vaccines/immunology
- Malaria Vaccines/therapeutic use
- Malaria, Falciparum/prevention & control
- Male
- Middle Aged
- Protozoan Proteins/adverse effects
- Protozoan Proteins/immunology
- Protozoan Proteins/therapeutic use
- Repetitive Sequences, Nucleic Acid
- Safety
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/therapeutic use
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453
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Gross M, Zoller WG. [Germline mutation and microsatellite instability in hereditary nonpolyposis colon carcinomas]. ZEITSCHRIFT FUR GASTROENTEROLOGIE 1996; 34:509-11. [PMID: 8967124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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454
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Camel E, O'Connell M, Sage B, Gross M, Maibach H. The effect of saline iontophoresis on skin integrity in human volunteers. I. Methodology and reproducibility. FUNDAMENTAL AND APPLIED TOXICOLOGY : OFFICIAL JOURNAL OF THE SOCIETY OF TOXICOLOGY 1996; 32:168-78. [PMID: 8921320 DOI: 10.1006/faat.1996.0120] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study, conducted in 36 human volunteers, was an evaluation of the effects of saline iontophoresis on skin temperature, irritation, and barrier function. The major objectives were to assess the effects of low-level ionic currents, to validate the proposed methodology of assessment, and to establish reproducibility in repeated saline iontophoresis applications. This was the first of a multistage study designed to assess the safety of 24-hr saline iontophoresis episodes at selected currents and current densities. Since an iontophoresis patch challenges the skin barrier both by occluding the skin surface and by passing ionic current through the skin, the experimental protocol was designed to permit measurement of the contribution of each of these processes to the overall response. In this first stage we investigated the effect of 10 min of current delivery, at 0.1 mA/cm2 on a 1-cm2 area patch and 0.2 mA/cm2 on a 6.5-cm2 area patch compared to unpowered control patches. Twelve subjects were tested under each condition on two separate occasions to examine reproducibility of the response variable measurements. A further 12 subjects were tested once under the 0.2 mA/cm2, 6.5-cm2 condition. Skin irritation was evaluated via repeated measurements of transepidermal water loss, capacitance, skin temperature, skin color, and a visual scoring system, before the iontophoresis episode and after patch removal. No damage to skin barrier function in terms of skin-water loss or skin-water content was detected. Slight, subclinical, short-lasting erythema was observed for both conditions. Assessment of correlation coefficients showed highly statistically significant indications of reproducibility for all five response variables measured. The experimental design, in combination with a repeated measures analysis, provided clear separation of the occlusion and ionic current components of the iontophoretic patch challenge. Further, the repeated measures analysis gave a highly sensitive assessment of skin irritation and resolution after patch removal. We conclude that the experimental methodology is appropriate for assessing possible changes in skin integrity resulting from saline iontophoresis under similar operating conditions for longer durations and for other skin challenges from which a subclinical response is expected.
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455
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Gross M. [Comment on the article by G. Friedrich. Quality assurance in phoniatry]. HNO 1996; 44:423. [PMID: 8964712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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456
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Gross M, Seage GR, Mayer KH, Goldstein RS, Losina E, Wold C. Interest among gay/bisexual men in greater Boston in participating in clinical trials of preventive HIV vaccines. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1996; 12:406-12. [PMID: 8673551 DOI: 10.1097/00042560-199608010-00012] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
To estimate interest in HIV preventive vaccine trials, we administered questionnaires to two otherwise demographically similar cohorts of older (mean 40 years) and younger (mean 23 years) gay men in Boston. Questionnaire responses were linked to concurrent behavioral and demographic data. Univariate analyses, performed separately for older and younger cohorts, identified factors that distinguished participants who were "very interested" from those who were "not at all interested". Multivariate logistic regression analyses were used to adjust for confounding. Among all 630 participants, 215 (34%) were "not at all" interested in participating, 306 (49%) were "somewhat" interested, and 102 (16%) were "very" interested. Older men were significantly more likely than younger men to be "very" interested and less likely to be "not at all interested." Among both older and younger men, perceived peer willingness to enroll in vaccine trials predicted interest after adjusting for confounding. Among older men, optimism about success in vaccine development also predicted interest. In the younger cohort, men recruited in community settings (e.g., bars, nightclubs) were more interested in vaccine trial participation than were those recruited by outreach workers and word of mouth on college campuses. Vaccine-induced seroconversion evoked significant concern.
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457
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Abstract
Folding of nascent chains resembles the decoding of spoken language in that information is emitted as a unidirectional, one-dimensional string of elements, with higher structures and long-distance interactions emerging with time. Applying a "pseudolinguistic' analysis of structure to a set of all 36 possible six-stranded antiparallel beta-sandwich topologies reveals new order principles and reduces the complexity of this family significantly. The simple connectivity diagrams ("linguistic trees') proposed here allow predictions of the speed and cooperativity of beta-sheet folding and help understanding the cotranslational folding from the N-terminus.
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458
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Gross M, Hessefort S. Purification and characterization of a 66-kDa protein from rabbit reticulocyte lysate which promotes the recycling of hsp 70. J Biol Chem 1996; 271:16833-41. [PMID: 8663320 DOI: 10.1074/jbc.271.28.16833] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We have purified to apparent homogeneity a 66-kDa protein from rabbit reticulocyte lysate which is associated with hsp 70. Our characterization of this 66-kDa protein demonstrates that its physiological role is to promote the recycling of hsp 70 by catalyzing the dissociation of hsp 70-bound ADP in exchange for ATP. We have therefore termed the 66-kDa protein RF-hsp 70, a recycling factor for hsp 70. RF-hsp 70 promotes stoichiometric binding of ATP to hsp 70, and it increases about 5-fold the rate of dissociation of hsp 70.ADP in the presence of ATP. This process represents adenine nucleotide exchange, since dissociation of ADP does not occur unless ATP is added; dATP, GTP, and ITP cannot substitute for ATP. The mechanism of action of RF-hsp 70 is to lower the KD of hsp 70 for ATP about 6-7-fold to a value that is close to the KDof hsp 70 for ADP. RF-hsp 70 also stimulates the ATPase activity of hsp 70, including the 42-kDa amino-terminal portion of hsp 70 generated by chymotrypsin, demonstrating that RF-hsp 70 interacts with that part of hsp 70 known to contain the ATP/ADP binding site. Confirming its recycling function, RF-hsp 70 stimulates about 7-10-fold the ability of hsp 70 to reactivate heat-denatured firefly luciferase. In addition, RF-hsp 70 acts catalytically to recycle hsp 70, since, at 0.2 times the molar concentration of hsp 70, RF-hsp 70 increases the rate of renaturation of luciferase by hsp 70 about 3-4-fold. The action of RF-hsp 70 is also partially species-specific since it is most effective with rabbit reticulocyte hsp 70, less effective with bovine brain hsp 70, even less effective with human hsp 70, and ineffective with broad bean hsp 70.
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459
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Gross M, Hessefort S, Olin A, Reddy G. Extensive sequencing of tryptic peptides of a rabbit reticulocyte 66-kDa protein that promotes recycling of Hsp 70. Homology To stress-related proteins. J Biol Chem 1996; 271:16842-9. [PMID: 8663319 DOI: 10.1074/jbc.271.28.16842] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Trypsinization and sequence analysis of the 66-kDa rabbit reticulocyte protein (RF-hsp 70), shown in the preceding article to function as a recycling protein for hsp 70, demonstrates striking similarity to the transformation-sensitive human protein IEF SSP 3521 (Honoré, B., Leffers, H., Madsen, P., Rasmussen, H. H., Vandekerckhove, J., and Celis, J. E.(1992) J. Biol. Chem. 267, 8485-8491) and mouse extendin (Blatch, G. L., Lassle, M., Takatori, T., Gandhi, T., Kundra, V., and Zetter, B. R.(1995) Proc. Am. Assoc. Cancer Res. 36, 68). The human and mouse proteins share 97% sequence identity, and sequencing of 20 polypeptides (225 residues) from RF-hsp 70 reveals only 10 differences between the rabbit and human proteins and 13 differences between the rabbit and mouse proteins (96 and 94% identity, respectively). In addition, all three proteins are of similar size, and each contains 11 cysteines. These findings strongly suggest that these three proteins are homologs of the same activity. All differences (but one) between the human and mouse proteins occur within the amino-terminal half of the protein, and there is only one difference among 121 sequenced residues between RF-hsp 70 and the human or mouse protein which occurs within the carboxyl-terminal 70% of the molecule. In addition, where partial sequences of RF-hsp 70 and p60, a chick oviduct protein that shows 70% identity to the human protein (Smith, D. F., Sullivan, W. P., Marion, T. N., Zaitsu, K., Madden, B., McCormick, D. J., and Toft, D. O. (1993) Mol. Cell. Biol. 13, 869-876), overlap (a total of 54 residues), RF-hsp 70 and chick p60 show 78% sequence identity. Studies of the initial digestion of RF-hsp 70 by trypsin indicate that it is first converted to 58- and 54-kDa components, each of which is then converted to a 43-kDa polypeptide. This 43-kDa component is located in the human and mouse proteins at position 124 to about 470. It is converted subsequently to a 31-kDa polypeptide by trypsin hydrolysis at position 207. This 31-kDa component is finally split into 17- and 14-kDa polypeptides that are located at positions 208 to approximately 351 and 352 to approximately 470, respectively. The 14-kDa polypeptide is relatively resistant to further digestion with trypsin, and seven tryptic peptides from other parts of RF-hsp 70 contain internal lysine and/or arginine residues (as do several tryptic peptides produced from IEF SSP 3521 and chick p60). Both features may be due to interference with trypsin action by secondary structure in the protein, since trypsinization of reduced and carboxymethylated RF-hsp 70 results in hydrolysis of the 14-kDa polypeptide and reduces the level of peptides that contain internal lysine and/or arginine, although it does not eliminate them.
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460
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Zoller WG, Gross M. Beta-blockers for prophylaxis of bleeding from esophageal varices in cirrhotic portal hypertension. Review of the literature. Eur J Med Res 1996; 1:407-16. [PMID: 9353240] [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] Open
Abstract
Hemorrhage from esophageal varices is a life-threatening event in patients with liver cirrhosis. About 40% to 80% of the patients surviving the first bleeding suffer from a recurrence of variceal bleeding within one year. This high recurrence rate substantially contributes to the mortality in patients with liver cirrhosis. Therefore, various treatment regimens both in primary and secondary prophylaxis were studied. Most experience in medical primary prophylaxis was collected with beta-blockers, mainly propranolol. Treating patients with esophageal varices with propranolol significantly reduces the incidence of first variceal bleeding. However, the effect on mortality is marginal, and primary prophylaxis is generally not recommended in these patients. Several studies support the hypothesis, that medical prophylaxis with beta-blockers is more effective in reducing the rate of first esophageal bleeding in patients with a high risk of hemorrhage, such as the presence of very large varices with red spots. A score to assess the individual risk of a given patient to suffer a variceal bleeding would be helpful. As long as such a score is not validated, no general rule for this treatment decision can be given. In secondary prophylaxis, both administration of beta-blockers and endoscopic therapy (sclerotherapy or ligation of the varices) are effective in significantly lowering the rate of re-bleeding. However, the effect on mortality was not significant in most studies. Several studies comparing the efficacy of medical prophylaxis and endoscopic treatment showed advantages of the endoscopic therapy with a greater reduction in recurrent bleeding episodes. However, medical prophylaxis with beta-blockers has the important advantage of being immediately effective whereas endoscopic procedures provide the best protection against recurrent bleeding after complete obliteration of the varices. Therefore, in the first weeks and months of endoscopic therapy, the additional treatment with beta-blockers may further reduce the risk of re-bleeding. Only half of all studies on this topic reported a significant advantage of such a combined therapy. Therefore, it seems reasonable to restrict this approach to patients with a high risk of re-bleeding such as patients with large sclerotherapy-derived esophageal ulcers.
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461
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Rieger A, Hass I, Gross M, Gramm HJ, Eyrich K. [Intubation trauma of the larynx--a literature review with special reference to arytenoid cartilage dislocation]. Anasthesiol Intensivmed Notfallmed Schmerzther 1996; 31:281-7. [PMID: 8767240 DOI: 10.1055/s-2007-995921] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Trauma to the cricoarytenoid joint represents a rare but serious complication of endotracheal intubation. Subluxation and luxation of the arytenoid cartilage may occur during difficult but also following uncomplicated intubation. Forces on the arytenoid cartilage exerted by the laryngoscope blade or by the distal part of the endotracheal tube may cause anterior and inferior displacement of the arytenoid cartilage. Due to the conventional intubation technique the left arytenoid cartilage is affected most frequently. Posterolateral subluxation is attributed to the pressure exerted on the posterior glottis by the convex part of the shaft of the tube. Systemic diseases (e.g. terminal renal insufficiency, bowel diseases, acromegaly) may cause degeneration of the cricoarytenoid ligaments, thus making the cricoarytenoid joint more susceptible to traumatic dislocation. Persisting alterations of voice, sore throat and pain on swallowing may hint to the diagnosis of arytenoid dislocation. However, stridor and shortness of breath have also been observed. If pharyngo-laryngeal complaints persist, evaluation by laryngologists is mandatory. In addition to indirect and direct laryngoscopy, computerised tomography and electromyography of the larynx play an important role in differentiating arytenoid dislocation from true vocal cord paralysis due to nerve damage. Early operative reposition results in fair prognosis, whereas delayed diagnosis may lead to ankylosis of the cricoarytenoid joint with permanent impairment of the voice and possibly compromised airway protection.
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462
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Sherwood JA, Copeland RS, Taylor KA, Abok K, Oloo AJ, Were JB, Strickland GT, Gordon DM, Ballou WR, Bales JD, Wirtz RA, Wittes J, Gross M, Que JU, Cryz SJ, Oster CN, Roberts CR, Sadoff JC. Plasmodium falciparum circumsporozoite vaccine immunogenicity and efficacy trial with natural challenge quantitation in an area of endemic human malaria of Kenya. Vaccine 1996; 14:817-27. [PMID: 8817830 DOI: 10.1016/0264-410x(95)00221-l] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
It has been hypothesized that antibody induced by Plasmodium falciparum circumsporozoite protein vaccine would be effective against endemic human malaria. In a malaria endemic region of Kenya, 76 volunteers, in 38 pairs sleeping adjacently, were immunized with subunit circumsporozoite protein Asn-Ala-Asn-Pro tetrapeptide repeat-pseudomonas toxin A, or hepatitis B vaccine. After quinine and doxcycycline, volunteers were followed for illness daily, parasitemia weekly, antibody, T-lymphocyte responses, and treated if indicated. Anopheles mosquitoes resting in houses were collected, and tested for P. falciparum antigen, or dissected for sporozoites and tested for blood meal ABO type and P. falciparum antigen. Vaccine was safe, with side-effects similar in both groups, and immunogenic, engendering IgG antibody as high as 600 micrograms ml-1, but did not increase the proportion of volunteers with T-lymphocyte responses. Estimation of P. falciparum challenge averaged 0.194 potentially infective Anopheles bites/volunteer/ day. Mosquito blood meals showed no difference in biting intensity between vaccine and control groups. Both groups had similar malaria-free survival curves, cumulative positive blood slides, cumulative parasites mm-3, and numbers of parasites mm-3 on first positive blood slide, during three post-vaccination observation periods. Every volunteer had P. falciparum parastemia at least once. Vaccinees had 82% and controls 89% incidences of symptomatic parasitemia (P = 0.514, efficacy 9%, statistical power 95% probability of efficacy < 50%). Vaccine-induced anti-sporozoite antibody was not protective in this study. Within designed statistical precisions the present study is in agreement with efficacy studies in Colombia, Venezuela and Tanzania.
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463
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Gulba DC, Gross M, Dechend R, Luft F, Sosada M, Frey U, Dietz R. [Thrombolytic therapy of renal artery embolism. An expanded case report with review of the literature]. Internist (Berl) 1996; 37:623-7. [PMID: 8767996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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464
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Dechend R, Mo X, Schulz W, Gross M, Praus M, Dietz R, Gulba D. Thrombin receptor and urokinase-type plasminogen activator are colocalized in vascular smooth muscle cells derived from human carotid atherosclerotic plaques. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0268-9499(96)80045-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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465
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Ryan J, Chuba PJ, Ben-Josef EB, Porter AT, Zalupski M, Lucas D, Patell N, Gross M, Shamsa FH, Brusseau T, Filipczak L, Fontanesi J. 13 Adjuvant brachytherapy for primary and recurrent soft-tissue sarcoma at WSU. Radiother Oncol 1996. [DOI: 10.1016/0167-8140(96)87817-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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466
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Gross M. [Diabetes--definition and classification]. OSTERREICHISCHE KRANKENPFLEGEZEITSCHRIFT 1996; 49:22-4. [PMID: 8716260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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467
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Fishbein EF, Cofield RE, Froidevaux L, Jarnot RF, Lungu T, Read WG, Shippony Z, Waters JW, McDermid IS, McGee TJ, Singh U, Gross M, Hauchecorne A, Keckhut P, Gelman ME, Nagatani RM. Validation of UARS Microwave Limb Sounder temperature and pressure measurements. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/95jd03791] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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468
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Giraudeau A, Ruhlmann L, El Kahef L, Gross M. Electrosynthesis and Characterization of Symmetrical and Unsymmetrical Linear Porphyrin Dimers and Their Precursor Monomers. J Am Chem Soc 1996. [DOI: 10.1021/ja9523956] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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469
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Yeom YI, Fuhrmann G, Ovitt CE, Brehm A, Ohbo K, Gross M, Hübner K, Schöler HR. Germline regulatory element of Oct-4 specific for the totipotent cycle of embryonal cells. Development 1996; 122:881-94. [PMID: 8631266 DOI: 10.1242/dev.122.3.881] [Citation(s) in RCA: 592] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The totipotent stem cells of the pregastrulation mouse embryo which give rise to all embryonic somatic tissues and germ cells express Oct-4. The expression is downregulated during gastrulation and is thereafter only maintained in the germline lineage. Oct-4/lacZ transgenes were used to determine how this pattern of expression was achieved, and resulted in the identification of two separate regulatory elements. The distal element drives Oct-4 expression in preimplantation embryos, in migratory and postmigratory primordial germ cells but is inactive in cells of the epiblast. In cell lines this element is specifically active in embryonic stem and embryonic germ cells. The proximal element directs the epiblast-specific expression pattern, including downregulation during gastrulation; in cell lines its activity is restricted to epiblast-derived cells. Thus, Oct-4 expression in the germline is regulated separately from epiblast expression. This provides the first marker for the identification of totipotent cells in the embryo, and suggests that expression of Oct-4 in the totipotent cycle is dependent on a set of factors unique to the germline.
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470
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Gross M, Wyss M, Furter-Graves EM, Wallimann T, Furter R. Reconstitution of active octameric mitochondrial creatine kinase from two genetically engineered fragments. Protein Sci 1996; 5:320-30. [PMID: 8745410 PMCID: PMC2143346 DOI: 10.1002/pro.5560050216] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Creatine kinase (CK) has been postulated to consist of two flexibly hinged domains. A previously demonstrated protease-sensitive site in M-CK (Morris & Jackson, 1991) has directed our attempts to dissect mitochondrial CK (Mi-CK) into two protein fragments encompassing amino acids [1-167] and [168-380]. When expressed separately in Escherichia coli, the two fragments yielded large amounts of insoluble inclusion bodies, from which the respective polypeptides could be purified by a simple two-step procedure. In contrast, co-expression of the two fragments yielded a soluble, active, and correctly oligomerizing enzyme. This discontinuous CK showed nearly full specific activity and was virtually indistinguishable from native Mi-CK by far- and near-UV CD. However, the positive cooperativity of substrate binding was abolished, suggesting a role of the covalent domain linkage in the crosstalk between the substrate binding sites for ATP and creatine. The isolated C-terminal fragment refolded into a native-like conformation in vitro, whereas the N-terminal fragment was largely unfolded. Prefolded [168-380] interacted in vitro with [1-167] to form an active enzyme. Kinetic analysis indicated that the fragments associate rapidly and with high affinity (1/K1 = 17 microM) and then isomerize slowly to an active enzyme (k2 = 0.12 min-1; k-2 = 0.03 min-1). Our data suggest that the C-terminal fragment of Mi-CK represents an autonomous folding unit, and that the folding of the C-terminal part might precede the conformational stabilization of the N-terminal moiety in vivo.
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471
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Zhu Y, Haddadian E, Mou T, Gross M, Liu J. Role of nucleation in the structure evolution of a magnetorheological fluid. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 53:1753-1759. [PMID: 9964436 DOI: 10.1103/physreve.53.1753] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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472
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Hess U, Gross M, Lehner K, Cavallaro A, Hannig C. [Initial diagnosis of melanoma metastasis to the spleen: case report of follow-up in atypical early invasion of the spleen]. RONTGENPRAXIS; ZEITSCHRIFT FUR RADIOLOGISCHE TECHNIK 1996; 49:23-24. [PMID: 8851542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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473
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Gross M. When and how to eradicate Helicobacter pylori: role of histamine receptor antagonists. Eur J Med Res 1996; 1:189-98. [PMID: 9386268] [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] Open
Abstract
Peptic ulcer is today frequently considered to be an infectious disease. The bacteria assumed to be the cause of gastric or duodenal ulcer was first called Campylobacter pyloridis and later C. pylori because of its structural similarity to other Campylobacter species. Later, unique characteristics were reported, and it was renamed Helicobacter pylori (Hp). In retrospect, it was presumably first described in man in 1938 (Doenges 1938), although the clinical significance was not established until 1983 (Warren 1983, Warren and Marshall 1983). It is a spiral-shaped, gram-negative bacteria with four to six flagella and dimensions of 0.5 x 3.0 micron. . With the help of these flagella, it moves into the mucous layer overlying the gastric epithelium where it colonizes at the interface of the mucous layer and the surface epithelial cells. It can be found in any part of the gastrointestinal tract demonstrating gastric epithelium, i.e. the stomach and metaplastic areas of the esophagus or the duodenum. One characteristic of this bacteria is the production of a urease enzyme that catalyzes urea to ammonium and bicarbonate. The production of ammonium causes the development of an alkaline microenvironment that protects it from the gastric acid. In the presence of urea, the organism will therefore replicate to a pH as low as 4.3 and survive without replication to a pH as low as 2.3. In Western countries, an increase in the prevalence of Hp infection is observed in the population with progressing age. In childhood, infection before the age of 20 years is rare. At the age of 60 years or older, however, the prevalence rate is on the order of 40% to 60% (Dooley et al. 1989, Perez-Perez et al. 1988, Marshall 1994). The seroconversion rate in adults is lower than 1% per year (Parsonnet et al. 1992). The infection seems to be stable, probably persisting for many years or even a lifetime.
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Chou J, Chen JJ, Gross M, Roizman B. Association of a M(r) 90,000 phosphoprotein with protein kinase PKR in cells exhibiting enhanced phosphorylation of translation initiation factor eIF-2 alpha and premature shutoff of protein synthesis after infection with gamma 134.5- mutants of herpes simplex virus 1. Proc Natl Acad Sci U S A 1995; 92:10516-20. [PMID: 7479831 PMCID: PMC40642 DOI: 10.1073/pnas.92.23.10516] [Citation(s) in RCA: 243] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The protein encoded by the gamma 134.5 gene of herpes simplex virus precludes premature shutoff of protein synthesis in human cells triggered by stress associated with onset of viral DNA synthesis. The carboxyl terminus of the protein is essential for this function. This report indicates that the shutoff of protein synthesis is not due to mRNA degration because mRNA from wild-type or gamma 134.5- virus-infected cells directs protein synthesis. Analyses of the posttranslational modifications of translation initiation factor eIF-2 showed the following: (i) eIF-2 alpha was selectively phosphorylated by a kinase present in ribosome-enriched fraction of cells infected with gamma 134.5- virus. (ii) Endogenous eIF-2 alpha was totally phosphorylated in cells infected with gamma 134.5- virus or a virus lacking the 3' coding domain of the gamma 134.5 gene but was not phosphorylated in mock-infected or wild-type virus-infected cells. (iii) Immune precipitates of the PKR kinase that is responsible for regulation of protein synthesis of some cells by phosphorylation of eIF-2 alpha yielded several phosphorylated polypeptides. Of particular significance were two observations. First, phosphorylation of PKR kinase was elevated in all infected cells relative to the levels in mock-infected cells. Second, the precipitates from lysates of cells infected with gamma 134.5- virus or a virus lacking the 3' coding domain of the gamma 134.5 gene contained an additional labeled phosphoprotein of M(r) 90,000 (p90). This phosphoprotein was present in only trace amounts in the immunoprecipitate from cells infected with wild-type virus or mutants lacking a portion of the 5' domain of gamma 134.5. We conclude that in the absence of gamma 134.5 protein, PKR kinase complexes with the p90 phosphoprotein and shuts off protein synthesis by phosphorylation of the alpha subunit of translation initiation factor eIF-2.
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Gross M, Gathof BS, Kölle P, Gresser U. Capillary electrophoresis for screening of adenylosuccinate lyase deficiency. Electrophoresis 1995; 16:1927-9. [PMID: 8586067 DOI: 10.1002/elps.11501601318] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We report a new screening method for adenylosuccinate lyase (ASase) deficiency using capillary electrophoresis (CE). This enzyme defect causes secondary autism and psychomotor retardation in early childhood. In all body fluids of these patients, two succinylpurine metabolites can be found that are normally not detectable: succinyladenosine and succinylaminoimidazole carboxamide (SAICA) riboside. A Beckman P/ACE 2050 capillary electrophoresis system was used with a 47.1 cm capillary, 75 microns ID, and the P/ACE Beckman UV absorbance detector. Untreated urine, injected for 1 s, was separated in a pH 8.63 borate buffer at 20 kV. The two succinylpurines (migration times 13.36 and 13.60 min) were detected at 254 nm only in urine of patients with ASase deficiency but not in control samples.
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