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D Brune

Publications and source records attributed to D Brune.

At least 19 recordsLinked to original sources
PubMed2006

ABRF ESRG 2005 study: identification of seven modified amino acids by Edman sequencing.

Identification of modified amino acids can be a challenging part for Edman degradation sequence analysis, largely because they are not included among the commonly used phenylthiohydantion amino acid standards. Yet many can have unique retention times and can be assigned by an experienced researcher or through the use of a guide showing their typical chromatography characteristics. The Edman Sequencing Research Group (ESRG) 2005 study is a continuation of the 2004 study, in which the participating laboratories were provided a synthetic peptide and asked to identify the modified amino acids present in the sequence. The study sample provided an opportunity to sequence a peptide containing a variety of modified amino acids and note their retention times relative to the common amino acids. It also allowed the ESRG to compile the chromatographic properties and intensities from multiple instruments and tabulate an average elution position for these modified amino acids on commonly used instruments. Participating laboratories were given 2000 pmoles of a synthetic peptide, 18 amino acids long, containing the following modified amino acids: dimethyl- and trimethyl-lysine, 3-methyl-histidine, N-carbamyl-lysine, cystine, N-methyl-alanine, and isoaspartic acid. The modified amino acids were interspersed with standard amino acids to help in the assessment of initial and repetitive yields. In addition to filling in an assignment sheet, which included retention times and peak areas, participants were asked to provide specific details about the parameters used for the sequencing run. References for some of the modified amino acid elution characteristics were provided and the participants had the option of viewing a list of the modified amino acids present in the peptide at the ESRG Web site. The ABRF ESRG 2005 sample is the seventeenth in a series of studies designed to aid laboratories in evaluating their abilities to obtain and interpret amino acid sequence data.

Amino Acid Sequence↗
PubMed2004

Randomised phase III study of intravenous vinorelbine plus hormone therapy versus hormone therapy alone in hormone-refractory prostate cancer.

BACKGROUND: Vinorelbine (VRL) has been shown to be active in hormone-refractory prostate cancer (HRPC) in phase II studies, alone or in combination. Its moderate toxicity profile is well tolerated in elderly patients. PATIENTS AND METHODS: Patients with metastatic prostate cancer, progressive after primary hormonal therapy, were randomised to receive intravenous VRL 30 mg/m2 on days 1 and 8 every 3 weeks, and hydrocortisone 40 mg/day or hydrocortisone alone until disease progression. Centres could choose to add aminoglutethimide 1000 mg/day to hydrocortisone as second-line hormone therapy (HT) for all their patients. Randomisation was stratified by centre. Further chemotherapy was allowed after progression. The primary end point was progression-free survival (PFS). The final analysis was performed on a total of 414 patients. Reported results were all based on intention-to-treat analyses. All progressions and responses were reviewed by an independent panel. RESULTS: PFS was significantly prolonged in the VRL plus HT arm compared with the HT alone arm, according to the statistical hypothesis of the protocol (P=0.055 in the two-sided log-rank test with a pre-specified significance level of 10%). The 6-month PFS rates were 33.2% versus 22.8%, and the median durations of PFS were 3.7 versus 2.8 months. In the multivariate Cox analysis, which included age, Karnofsky performance status (PS), haemoglobin, alkaline phosphatase at study entry and number of prior hormonal treatments, the P value was decreased to 0.005. The prostate-specific antigen (PSA) response rate (> or =50% decline sustained for at least 6 weeks) was significantly higher for VRL plus HT compared with HT (30.1% versus 19.2%; P=0.01). Clinical benefit, defined as a decrease in pain intensity or analgesic consumption or an improvement of Karnofsky PS for at least 9 weeks, and at least stable assessment in the other two, was also more frequently observed in patients who received VRL plus HT versus HT alone (30.6% and 19.2%; P=0.008). There was no statistical difference in overall survival. Forty-three per cent of patients in the HT arm received at least one line of further chemotherapy after progression, compared with 28% of patients in the VRL-based arm. Aminoglutethimide did not seem to result in better efficacy for either arm. VRL plus HT was well tolerated, with a median administered relative dose intensity of 90%; grade 4 neutropenia occurred in 6.5% of patients and non-haematological toxicity was rare. CONCLUSIONS: The combination of VRL and hydrocortisone compared with hydrocortisone alone resulted in improved clinical benefit, PFS and PSA response rate. This therapeutic gain is similar to that previously reported with mitoxantrone in combination with low-dose corticosteroids. There was no gain in survival; however, the combination is well tolerated in this elderly group of patients, who often present cardiac co-morbidities, and therefore offers an active and safe therapeutic option for patients with hormone-refractory prostate cancer.

Aged↗
PubMed2003

The influence of detergents and amphiphiles on the solubility of the light-harvesting I complex.

The effect of detergents and amphiphiles on protein solubility and their use in crystallization solutions was examined for an integral membrane protein, the light-harvesting I complex from Rhodospirillum centenum. Measurement by a centrifugation assay of the solubility of the protein in different detergents and amphiphiles showed high protein-solubility values when either octyl glucoside or lauryldimethylamine-N-oxide was present with heptanetriol or when deoxycholate was present with spermine. The detergent/amphiphile combinations that resulted in high protein solubility were shown to be successful for crystallization of the protein, suggesting that crystallization is favored for detergents and amphiphiles that optimize the solubility of integral membrane proteins. The amphiphiles effective for crystallization were found using laser mass spectrometry to displace the lauryldimethylamine-N-oxide bound to the protein. These results suggest that mass spectrometry can be used for screening of favorable crystallization conditions.

Centrifugation↗
PubMed2002

Interactions between lipids and bacterial reaction centers determined by protein crystallography.

The structure of the reaction center from Rhodobacter sphaeroides has been solved by using x-ray diffraction at a 2.55-A resolution limit. Three lipid molecules that lie on the surface of the protein are resolved in the electron density maps. In addition to a cardiolipin that has previously been reported [McAuley, K. E., Fyfe, P. K., Ridge, J. P., Isaacs, N. W., Cogdell, R. J. & Jones, M. R. (1999) Proc. Natl. Acad. Sci. USA 96, 14706-14711], two other major lipids of the cell membrane are found, a phosphatidylcholine and a glucosylgalactosyl diacylglycerol. The presence of these three lipids has been confirmed by laser mass spectroscopy. The lipids are located in the hydrophobic region of the protein surface and interact predominately with hydrophobic amino acids, in particular aromatic residues. Although the cardiolipin is over 15 A from the cofactors, the other two lipids are in close contact with the cofactors and may contribute to the difference in energetics for the two branches of cofactors that is primarily responsible for the asymmetry of electron transfer. The glycolipid is 3.5 A from the active bacteriochlorophyll monomer and shields this cofactor from the solvent in contrast to a much greater exposed surface evident for the inactive bacteriochlorophyll monomer. The phosphate atom of phosphatidylcholine is 6.5 A from the inactive bacteriopheophytin, and the associated electrostatic interactions may contribute to electron transfer rates involving this cofactor. Overall, the lipids span a distance of approximately 30 A, which is consistent with a bilayer-like arrangement suggesting the presence of an "inner shell" of lipids around membrane proteins that is critical for membrane function.

Cardiolipins↗
PubMed2002

Quality of life in long-term survivors of testicular cancer: a population-based case-control study.

PURPOSE: To evaluate quality of life and social problems in long-term survivors of testicular cancer. PATIENTS AND METHODS: In 1998, 71 testicular cancer survivors (cases) identified from the Calvados General Tumor Registry were enrolled onto a case-control study. One hundred nineteen healthy control subjects (controls), matched by age and location of residence, were selected at random from electoral rolls. Three self-administered questionnaires were used: two health-related quality-of-life questionnaires (Short Form-36 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 core questionnaires) and one life situation questionnaire. Specific questions concerning sexuality were also added. RESULTS: With a mean follow-up of 11 years, health-related quality-of-life scores did not differ significantly between cases and controls, nor did general symptom scores. Psychosocial problems were reported equally by cases and controls. Cases reported more modification of sexual life (P =.04) with decreased sexual enjoyment (P <.01), decreased desire (P =.02), and infertility (P <.01). Cases did not report more divorce than controls; they reported fewer changes in relationships with friends (P =.03). Although a similar proportion of cases and controls were at work, cases expressed less ambitious professional plans (P =.002). Cases had greater difficulty in borrowing from banks (P <.001). CONCLUSION: French long-term survivors of testicular cancer do not express more impairment of health-related quality of life or familial or professional life in comparison with healthy men. They did have more sexual life problems and found difficulty in borrowing from banks. This information should be used by practitioners to help their patients cope with their disease and return to normal life.

Adult↗
PubMed2002

[Standards, options, and recommendation for external radiotherapy of prostatic cancer: evaluation of the effect of dosage].

CONTEXT: The "Standards, Options and Recommendations" (SOR) collaborative project was initiated in 1993 by the Federation of the French Cancer Centres (FNCLCC), with the 20 French Regional Cancer Centres, several French public university and general hospitals, as well as private clinics and medical speciality societies. Its main objective is the development of serviceable clinical practice guidelines in order to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review, followed by critical appraisal by a multidisciplinary group of experts. Draft guidelines are produced, then validated by specialists in cancer care delivery. OBJECTIVES: Produce clinical practice guidelines for the radiotherapy of prostate cancer using the methodology developed by the Standards, Options and Recommendations project. METHODS: The FNCLCC and the French Urology Association (AFU) designated the multidisciplinary group of experts. Available data were collected by a search of Medline and lists selected by experts in the group. A first draft of the guidelines was written, they validated by independent reviewers. RESULTS: The main recommendations are: 1/ a minimal dose of 70 Gy must be used, whatever the prognostic factors; 2/ it appeared that patients with favourable prognostic indicators (stage T1-2, PSA < or = 10 micrograms/L and Gleason score < or = 6) do not benefit from a dose escalation effect for doses over 70-74 Gy; 3/ patients with intermediate prognosis are the ones who benefit most from the dose escalation effect over 74 Gy, provided they receive exclusive radiation therapy; 4/ whenever possible, patients should be included in controlled trials designed to assess the effects of dose escalation and hormonotherapy.

Humans↗
PubMed2001

Comparative analysis of amyloid-beta chemical structure and amyloid plaque morphology of transgenic mouse and Alzheimer's disease brains.

We have undertaken an integrated chemical and morphological comparison of the amyloid-beta (Abeta) molecules and the amyloid plaques present in the brains of APP23 transgenic (tg) mice and human Alzheimer's disease (AD) patients. Despite an apparent overall structural resemblance to AD pathology, our detailed chemical analyses revealed that although the amyloid plaques characteristic of AD contain cores that are highly resistant to chemical and physical disruption, the tg mice produced amyloid cores that were completely soluble in buffers containing SDS. Abeta chemical alterations account for the extreme stability of AD plaque core amyloid. The corresponding lack of post-translational modifications such as N-terminal degradation, isomerization, racemization, pyroglutamyl formation, oxidation, and covalently linked dimers in tg mouse Abeta provides an explanation for the differences in solubility between human AD and the APP23 tg mouse plaques. We hypothesize either that insufficient time is available for Abeta structural modifications or that the complex species-specific environment of the human disease is not precisely replicated in the tg mice. The appraisal of therapeutic agents or protocols in these animal models must be judged in the context of the lack of complete equivalence between the transgenic mouse plaques and the human AD lesions.

Alzheimer Disease↗
PubMed2001

[Standards, Options, and Recommendations for brachytherapy in patients with prostate cancer: efficacy and toxicity].

CONTEXT: The "Standards, Options and Recommendations" (SOR) collaborative project was initiated in 1993 by the Federation of the French Cancer Centres (FNCLCC), with the 20 French Regional Cancer Centres, several French public university and general hospitals, as well as private clinics and medical specialty societies. Its main objective is the development of serviceable clinical practice guidelines in order to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review, followed by a critical appraisal by a multidisciplinary group of experts. Draft guidelines are produced, then validated by specialists in cancer care delivery. OBJECTIVES: Produce clinical practice guidelines for the brachytherapy of prostate cancer using the methodology developed by the Standards, Options and Recommendations project. METHODS: The FNCLCC and the French Urology Association (AFU) first designated the multidisciplinary group of experts. Available data were collected by a search of Medline and lists selected by experts in the group. A first draft of the guidelines was written, they validated by independent reviewers. RESULTS: The main recommendations are: 1/Brachytherapy with permanent seeds alone is a possible curative treatment for prostate cancer patients with the following prognosis factors: tumour stage T1 or T2a (TNM 1992), Gleason score < or = 6 and PSA < 10 micrograms/L. 2/Combined treatment with brachytherapy and hormonal therapy could be more efficient than brachytherapy alone for prostate cancer patients with Gleason score > 7 and/or PSA > 10.3/Combination of brachytherapy and external beam radiation therapy can be proposed to prostate cancer patients with intermediate prognosis. 4/Before and after seed implantation, risks of infection must be prevented by appropriate antibiotic therapy (recommendation). 5/Brachytherapy must not be performed within 2 months of transurethral prostate resection. 6/The height of the urethra receiving more than 200% of the prescribed dose must be reported. The portion of the rectum receiving 100 and 120% of the prescribed dose must be limited to 10 and 5 mm length, respectively.

Antineoplastic Agents, Hormonal↗
PubMed1998

Chlorophyll alpha synthesis upon interruption and deletion of por coding for the light-dependent NADPH: protochlorophyllide oxidoreductase in a photosystem-I-less/chlL- strain of Synechocystis sp. PCC 6803.

The gene coding for the light-dependent NADPH:protochlorophyllide oxidoreductase (POR) was interrupted or deleted in a Synechocystis sp. PCC 6803 strain lacking photosystem I (PS I) as well as ChlL, which takes part in light-independent catalysis of protochlorophyllide reduction. Interruption of por by a kanamycin-resistance cartridge between the codons for M263 and V264 (about 83% into the coding region) did not abolish POR activity, but resulted in a decrease in the protochlorophyllide-(PChlide)-binding capacity of POR. Deletion of por in the PS I-less/chlL- strain generated a mutant [PS I-less/chlL-/por (del)] which accumulated both monovinyl-PChlide and divinyl-PChlide and excreted PChlides into the medium. This mutant also synthesized small amounts of protochlorophyllide dihydrogeranylgeraniol ester (protochlorophyll) when it was grown under light-activated heterotrophic growth conditions. However, the mutant was still able to synthesize small amounts of normal chlorophyll a under weak continuous illumination, even though the quantum yield of chlorophyll a formation was reduced. Either protochlorophyll or PChlide reduction by an unspecific reductase or by a ChlB/ChlN complex could account for chlorophyll a synthesis in the PS I-less/chlL-/por (del) strain. Functional photosystem II (PS II) was assembled in this mutant, but the PS II/chlorophyll ratio was fourfold lower than in the PS I-less strain with normal chlorophyll synthesis. The PS I-less/chlL-/por (del) mutant had a 77-K fluorescence emission maximum at 685 nm but no peak or shoulder at 695 nm when the cells were excited at 435 nm. Much of the chlorophyll in the PS I-less/chlL-/por (del) mutant therefore seems to be associated with components other than PS II.

Chlorophyll↗
PubMed1998

Liarozole--a novel treatment approach for advanced prostate cancer: results of a large randomized trial versus cyproterone acetate. Liarozole Study Group.

OBJECTIVES: To compare the efficacy of oral liarozole, the first retinoic acid metabolism-blocking agent (RAMBA) to be developed as differentiation therapy for human solid tumors, with that of cyproterone acetate (CPA), an antiandrogen for the treatment of metastatic prostate cancer. Liarozole promotes differentiation of cancer cells by increasing the intratumoral levels of retinoic acid. METHODS: A total of 321 patients with metastatic prostate cancer in relapse after first-line endocrine therapy entered a Phase III international multicenter study (recruitment from February 1992 to August 1994) comparing liarozole (300 mg two times daily) with CPA (100 mg two times daily). RESULTS: Accounting for differences in baseline prognostic factors, the adjusted hazard ratio for survival was 0.74 in favor of liarozole (P = 0.039), indicating a 26% lower risk of death than in patients treated with CPA. Median crude (unadjusted) survival time was the same in the liarozole group as in the CPA group (10.3 months). More patients showed a PSA response (at least 50% reduction in PSA from baseline) when treated with liarozole (20%) than with CPA (4%) (P < 0.001). Prostate-specific antigen (PSA) responders had a median survival benefit of 10 months over nonresponders, irrespective of treatment (hazard ratio 0.43; P = 0.0018). PSA response was apparent within 3 months in approximately 90% of patients who responded. Pain improved more in the liarozole group than in the CPA group (P = 0.03). PSA responders had lower median pain scores than nonresponders (1.7 versus 2.5) and better quality of life (median Functional Living Index-Cancer score 108 versus 98) at end point, ie, treatment discontinuation, as well as throughout the treatment period. Among the most frequently occurring adverse events in the liarozole group were dry skin (51% of patients), pruritus (25%), rash (16%), nail disorders (16%), and hair loss (15%). These adverse events were generally mild to moderate in severity and did not affect the overall quality of life score. There were no detectable effects of either treatment on vital signs such as blood pressure, heart rate, electrocardiogram, and body weight. CONCLUSIONS: Liarozole is superior to CPA in terms of PSA response, PSA progression, and survival, and is capable of maintaining patients' quality of life. The observed adverse events were mild to moderate in nature. These results show that liarozole is a possible treatment option after first-line endocrine therapy has failed.

Aged↗
PubMed1998

Health-related quality of life and sequelae in patients treated with brachytherapy and external beam irradiation for localized prostate cancer.

PURPOSE: To evaluate late physical and psychosocial sequelae in patients treated with an association of external beam irradiation (EBI) and brachytherapy (BT) for localized prostate cancer. PATIENTS AND METHODS: Seventy-one patients free of disease, treated at the Centre François Baclesse from 1988 to 1992, were enrolled in a case-control study. Seventy-one healthy controls, matched on age and residence, were selected at random from electoral rolls. Two self-administered questionnaires were mailed in January 1996. The French translation of the Nottingham Health Profile questionnaire and the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 core questionnaire were used to evaluate physical, role, emotional, cognitive and social functioning, global health status as well as energy and sleep disturbance. Specific problems related to prostate cancer were explored using the prostate specific module developed by the EORTC Genito-Urinary Tract Cancer Cooperative Group. Concordance between clinical complications reported by patients and those reported by physicians was also analyzed. RESULTS: General health quality of life scale scores did not significantly differ between patients and controls, nor did general symptom scale scores. Furthermore, no more late psychosocial sequelae were reported by patients than by controls. No major digestive complications were observed among patients. However, statistical differences were observed concerning interest in sex (P = 0.016) and sexual activity (P < 0.001), urinary incontinence (P < 0.001) and cystitis (P = 0.01). Late subjective morbidity (dysuria, nocturia, urinary incontinence, pelvic pain) appraisal differed slightly between patients and physicians who generally underestimate its severity. While nocturia was reported more often by physicians than by patients (P = 0.0016), patients reported urinary incontinence and pelvic pain more often than physicians (P < 0.001 and P < 0.001, respectively). CONCLUSIONS: The study demonstrates that survivors from localized prostate cancer treated with an association of BT and EBI have good global health status. Major problems that persist are sexual disorders, urinary incontinence and cystitis while digestive disorders were rare. This association could be an alternative to standard EBI in patients with localized prostate cancer. Whatever the treatment choice, patients should be involved in the therapeutic decision which should consider not only expected survival rate but also quality of life.

Aged↗
PubMed1994

Hydrodynamic steering effects in protein association.

Protein-ligand reaction rates are often limited by the rate of diffusional encounter of the protein and ligand in solution. Reaction rates, however, can be much greater than expected, given the necessity for correct orientation before reaction. A number of forces can affect the orientation of the protein and ligand in solution, and thus increase the reaction rate. We have considered hydrodynamic forces, produced when water molecules between protein and ligand must be pushed out of the way to allow their encounter. We have used the cleft enzymes as a model system, as they could be expected to show strong hydrodynamic effects. One particular type of hydrodynamic interaction stands out: a steering torque which occurs when the enzyme and substrate move toward each other in solution. The magnitude of this steering torque is compared to the mutual torque experienced by interacting "protein-sized" dipoles in solution. A simple model is used to demonstrate that the hydrodynamic steering torque can be 2 orders of magnitude greater than the electrostatic torque.

Biophysical Phenomena↗
PubMed1994

Patient and staff needs drive changes on a postsurgical unit.

In response to a dynamic health care environment and influenced by fiscal pressures, "business as usual" on the postsurgical unit at University of Nebraska Medical Center required examination. Both internal and external factors prompted a staff-driven task force to plan and implement changes. The task force consisted of representatives from staff and management to redesign current practices collaboratively. Issues addressed were nursing workload, responsibilities, scheduling, patient satisfaction, job satisfaction, and professional development. Expected outcomes of changes in the work design on the unit centered on increased efficiency of nursing time, cost effectiveness, and increased satisfaction of patients and nursing staff. The task force proposed and implemented innovative changes in the report and documentation system, utilization of nonprofessional staff, and redesign of work hours. The article presents these changes in the work environment and focuses on a written report system and a clearly defined role for nonprofessional staff.

Academic Medical Centers↗
PubMed1993

Biological specimen bank for smelter workers.

The biological specimen bank was initiated by the department of Environmental Medicine and the department of Medicine at the University of Umeå in 1975. The aims of the bank are to collect information on trace elements in human organs. Special attention is focused on the influence of occupational exposure. Tissue samples are taken from deceased workers from a copper and lead smelter in northern Sweden. Control specimens have been collected from deceased normal individuals from four control areas. Lung, liver and kidney samples are collected with quartz instruments and stored in quartz ampoules to avoid contamination. Other samples, e.g. bone, brain, fat, hair, heart muscle, nails, skin and stomach are taken with common autopsy instruments and stored in acid-washed polyethene vessels. The samples are stored at -20 degrees C. The elements Sb, As, Cd, Cr, Co, La and Se are analyzed by neutron activation analysis, Pb and Zn by atomic absorption spectrophotometry. The findings over time can be related to a number of factors: normal values in tissues, airborne exposure and causes of death. Special attention is paid variation over time, reevaluation of threshold limit values and risk assessment.

Autopsy↗
PubMed1993

Predicting protein diffusion coefficients.

Diffusion coefficients for proteins in water are predicted. The numerical method developed is general enough to be applied to a wide range of protein surface shapes, from rodlike to globular. Results are presented for lysozyme and tobacco mosaic virus, and they are compared with actual data and with predictions made by less general methods.

Diffusion↗
PubMed1993

International project for producing reference values for concentrations of trace elements in human blood and urine--TRACY.

In assessing the concentrations of toxic metals, such as cadmium, chromium, and mercury, in human blood and urine samples to determine whether they are abnormal or not, reliable reference values are needed from populations of nonoccupationally exposed subjects. Numerous publications present concentrations claimed to be typical for the study populations, but they can differ by up to an order of magnitude for a particular element. This is the consequence of general problems that are related to the definition of the reference groups, and the sampling and analytical procedures used, and that make it difficult to define typical and unbiased values. An international group of experts now establishes criteria and procedures to evaluate publications containing information on the concentrations of metals in tissues and body fluids for reference populations. These evaluations have been compiled in a data base (TRACY).

Hazardous Substances↗
PubMed1993

Normal concentrations of chromium in serum and urine--a TRACY project.

The validity of "normal" concentrations for total chromium in serum and urine (S-Cr and U-Cr, respectively) in papers published mainly in the last decade were evaluated and graded by two investigators according to TRACY criteria. The results were in close agreement. Because of possible contamination during sampling from stainless steel needles, the description of the sample collection method was considered important. Documentation of analytical quality control was emphasized. The chromium concentrations were categorized according to nonoccupational conditions that could influence the levels. Eighty-seven publications reporting chromium concentrations in blood and 58 on U-Cr were evaluated, 53 dealing with S-Cr and 41 with U-Cr being found suitable for the TRACY project. In selected publications the arithmetic mean values presented for S-Cr and U-Cr in individuals with no known exposure were within the following ranges: 1-3 nmol.1-1 for S-Cr and 2-10 nmol.1-1 or 0.2-1 mumol.mol creatinine-1 for U-Cr.

Chromium↗