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1.
Public Health ; 175: 8-18, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31374453

ABSTRACT

OBJECTIVE: The objective of this review was to analyse how researchers conducting studies about mobile health applications (MHApps) effectiveness assess the conditions of this effectiveness. STUDY DESIGN: A scoping review according to PRIMSA-ScR checklist. METHODS: We conducted a scoping review of efficacy/effectiveness conditions in high internal validity studies assessing the efficacy of MHApps in changing physical activity behaviours and eating habits. We used the PubMed, Web of Science, SPORTDiscus and PsycINFO databases and processed the review according to the O'Malley and PRISMA-ScR recommendations. We selected studies with high internal validity methodologies (randomised controlled trials, quasi-experimental studies, systematic reviews and meta-analyses), dealing with dietary and/or physical activity behaviours; covering primary, secondary or tertiary prevention and dealing with behaviour change (uptake, maintenance). We excluded articles on MHApps relating to high-level sport and telemedicine. The process for selecting studies followed a set protocol with two authors who independently appraised the studies. RESULTS: Twenty-two articles were finally selected and analysed. We noted that the mechanisms and techniques to support behaviour changes were poorly reported and studied. There was no explanation of how these MHApps work and how they could be transferred or not. Indeed, the main efficacy conditions reported by authors refer to practical aspects of the tools. Moreover, the issue of social inequalities was essentially reduced to access to the technology (the shrinking access divide), and literacy was poorly studied, even though it is an important consideration in digital prevention. All in all, even when they dealt with behaviours, the evaluations were tool-focused rather than intervention-focused and did not allow a comprehensive assessment of MHApps. CONCLUSION: To understand the added value of MHApps in supporting behaviour changes, it seems important to draw on the paradigms relating to health technology assessment considering the characteristics of the technologies and on the evaluation of complex interventions considering the characteristics of prevention. This combined approach may help to clarify how these patient-focused MHApps work and is a condition for improved assessment of MHApps in terms of effectiveness, transferability and scalability.


Subject(s)
Exercise/psychology , Feeding Behavior/psychology , Mobile Applications , Telemedicine , Humans , Randomized Controlled Trials as Topic
2.
Rev Mal Respir ; 36(2): 162-170, 2019 Feb.
Article in French | MEDLINE | ID: mdl-30686560

ABSTRACT

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a common but under-diagnosed pathology in primary care. The objective was to study the feasibility of a randomized controlled trial in general practice to detect new cases of COPD at an earlier stage. METHODS: A cluster randomized, controlled, multicenter intervention study comparing, according to a 2×2 factorial plan, two case finding strategies: a systematic GOLD-HAS hetero-questionnaire and coordination of the patient's path to facilitate access to spirometry. The PIL-DISCO pilot study took place in 2017. Patients between 40 and 80 years old, with no previous history of COPD, consulting their GP on a given day regardless of the reason, were included. RESULTS: 176 patients were included in 1.5 days. Spirometry was performed in none of the control arm, in 13 (29.5%) of the questionnaire arm, in 22 (50%) in the coordination arm and in 32 (72.7%) with the combination of the two strategies. Two cases of stage 2 COPD and thirteen other respiratory diseases were diagnosed. CONCLUSIONS: This study confirms the feasibility of the protocol in primary care in terms of speed of inclusion and acceptability. An extension phase aiming to include 3200 patients will assess the diagnostic value of the two strategies tested in general practice.


Subject(s)
Mass Screening/methods , Primary Health Care/methods , Pulmonary Disease, Chronic Obstructive/diagnosis , Adult , Aged , Aged, 80 and over , Early Diagnosis , Feasibility Studies , Female , Forced Expiratory Volume , General Practice/methods , Humans , Male , Middle Aged , Program Evaluation , Spirometry/methods
3.
Infect Dis (Lond) ; 47(10): 725-31, 2015.
Article in English | MEDLINE | ID: mdl-26077036

ABSTRACT

BACKGROUND: Intravesical bacillus Calmette-Guerin (BCG) therapy is an effective and widely used treatment for superficial bladder carcinoma. Local complications are frequent whereas systemic complications are rare but can be serious, and their management is not well known. METHODS: We describe retrospectively the records of 22 patients treated in 3 infectious disease departments, for complications related to intravesical BCG therapy as treatment of bladder cancer. RESULTS: All the patients were male, with a median age of 68 years (range 56-88). Complications occurred after a median of 5 instillations (range 1-11) and were observed within 24 h following BCG instillation for 14 patients. Common symptoms were fever (n = 20), impaired general condition (n = 14), and shortness of breath (n = 7). Six patients had a systemic septic reaction leading to transfer into the intensive care unit for five of them. Lung infiltration was the most frequent presentation (n = 11). Mycobacterium bovis was isolated from only two patients, but histology showed the presence of a granuloma in nine patients. Antimycobacterial treatment was initialized in 17 patients; the outcome was favorable in 16 patients, with a median length of symptoms resolution of 22.5 days (range 5-425 days). Eleven patients received corticosteroids in addition to specific treatment and had a more rapid improvement. One patient died with disseminated BCGitis proved by biopsy. CONCLUSIONS: Complications following intravesical BCG therapy are rare but can be severe and fatal. Histology seems to be the method that contributes most in confirmation of the diagnosis. Antimycobacterial therapy is effective, and probably more efficient when combined with corticosteroids, but the regimen and duration of the treatment are not standardized.


Subject(s)
Antineoplastic Agents/adverse effects , BCG Vaccine/administration & dosage , BCG Vaccine/adverse effects , Mycobacterium bovis/isolation & purification , Urinary Bladder Neoplasms/therapy , Administration, Intravesical , Adrenal Cortex Hormones/administration & dosage , Adult , Aged , Aged, 80 and over , Animals , Antineoplastic Agents/administration & dosage , Cattle , Drug Therapy, Combination , Granuloma/microbiology , Humans , Male , Middle Aged , Mycobacterium bovis/drug effects , Retrospective Studies , Urinary Bladder Neoplasms/complications
4.
Health Promot Int ; 26(3): 302-10, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21208940

ABSTRACT

The objectives of the study were to identify the professional issues that teachers perceived as important in their commitment to a health promotion (HP) programme launched in their schools and to understand their perceptions of the impact of the programme on themselves as professionals, individuals, on students, on school staff and on the relationship with students' families. A mixed methods design was used. An anonymous questionnaire was distributed to 54 participating teachers exploring their practices and perceptions of the programme and 26 semi-structured interviews were conducted which examined their professional commitment to the programme. The main factors that teachers identified as shaping their commitment were (1) their perceptions of the programme, specifically, its congruence with their own role and practice and also their perceived impact of the programme upon whole staff relations and (2) the specific school environment including school organization, quality of the relationships with parents and student behaviour. If HP programmes are to be successfully developed in schools, it is necessary to anchor them within the schools' mission. HP programmes need to make sense to teachers' educational perspectives. They need to be responsive to school needs. They also need to be cognisant of the internal tensions that programme implementation can engender among the whole staff, some of whom may be committed to HP in their school, while others, may not value HP in the same way. Therefore, implementation processes that are respectful of the challenges schools encounter and of the differing ontological perspectives that teachers may hold with regard to HP is important.


Subject(s)
Faculty , Health Promotion/organization & administration , Professional Role/psychology , Environment , Health Behavior , Humans , Perception , Surveys and Questionnaires
6.
Opt Express ; 15(5): 2573-84, 2007 Mar 05.
Article in English | MEDLINE | ID: mdl-19532495

ABSTRACT

An output coupler comprising a resonant grating submirror monolithically associated with a standard multilayer submirror polarizes the emission of a Nd:YAG microchip laser linearly over its full emission bandwidth by intra-mirror destructive interference for the undesired polarization. A polarization extinction ratio of more than 25 dB is obtained up to 6.1microJ pulse energy. This passively Q-switched laser performance is almost identical to that of a gratingless non-polarized microchip laser. The design and fabrication of the resonant grating mirror are described.

7.
Opt Express ; 15(25): 16520-6, 2007 Dec 10.
Article in English | MEDLINE | ID: mdl-19550942

ABSTRACT

We demonstrate the use of a High Reflectivity Grating (HRG) as an intra-cavity element in a Semiconductor Disk Laser (or Vertical External Cavity Surface Emitting Laser) to stabilise its emission wavelength and polarization characteristics. Operation at 1058nm with up to 645mW of pump-limited output power and an M(2)~1.4 is achieved. We also show that this scheme permits tunable single-frequency operation.

8.
Opt Express ; 13(9): 3230-5, 2005 May 02.
Article in English | MEDLINE | ID: mdl-19495223

ABSTRACT

A resonant diffraction grating comprising a mirror, a dielectric layer and a high index corrugation at the layer-air interface is shown to exhibit off-Littrow the record diffraction efficiency of 99% in the -1st reflected order at 1064 nm wavelength thanks to the excitation of a leaky mode of the layer. Such high figure is obtained by a grating 5 to 10 times shallower than in current attempts to realize high efficiency all-dielectric gratings.

9.
Sante Publique ; 16(2): 197-206, 2004 Jun.
Article in French | MEDLINE | ID: mdl-15360174

ABSTRACT

Reflection upon the role of nurses in public health is not something new; however, over the past few years, a questioning and similar reports have sprung up pointing to the difficulty perceived by nurses in reconciling their professional practice and public health. Currently, in light of the evolution of public health, where does the practice of nursing fit into public health practice? What are the potential movements and trends in terms of training? The goal of this paper is to present a number of possible avenues for thought on the subject, namely concerning the training and the allocation of competencies. It would be undoubtedly a pity to conceive of public health training today being intended only for nurses. It is rather preferable that post-graduate public health training is aimed at a variety of professional categories, regardless of their initial training or degree course. The development of schools of public health to which nurses could have access in the same way that other health professionals or from the social and educational fields do is critical. Above and beyond what is at stake for specialisation, and even independent of the implication of nurses in public health work, the current trend to re-balance the work and tasks of both nurses and doctors constitutes a significant challenge for public health.


Subject(s)
Nurse's Role , Public Health Nursing/trends , Education, Nursing , Humans , Politics , Public Health Nursing/economics , Workforce
10.
Sante Publique ; 16(2): 383-92, 2004 Jun.
Article in French | MEDLINE | ID: mdl-15360195

ABSTRACT

The objective of this work was to study hospital nurses' perceptions of public health based on a pedagogical exercise. A qualitative study, lead by students of a training institute for nursing care (IFSI), was conducted using semi-directed interviews of hospital nurses from different departments of a provincial hospital. The main results show that for one-third of the nurses interviewed, the hospital is not a setting for public health practice. In terms of their definition of public health, it is closely linked to the concept of prevention, with primarily individual approaches. This definition is very close to the public health activities that they conduct at the hospital and which are centred on information and disease prevention, on education related to pathologies and the relationship between the provision of care and listening to the patients and their families. Few nurses place their public health activities within the scope of the areas of hospital cleanliness, the welcoming of the patients, the organisation of services, and the improvement of the quality of care. The potential tracks which have emerged from this work lead to the need for the strengthening of training in patient education, in the hospital's work networking with external partners, and in better development of public health activities undertaken in the hospital setting.


Subject(s)
Attitude of Health Personnel , Nurse's Role , Nursing Staff, Hospital , Public Health , Adult , Data Collection , Humans , Patient Education as Topic , Preventive Medicine
11.
Sante Publique ; 16(1): 75-93, 2004 Mar.
Article in French | MEDLINE | ID: mdl-15185587

ABSTRACT

Whereas today we have good, solid knowledge of the perception of health and its objectives from the perspective of youth, the recommendations of the High Commission on Public Health are geared towards the implementation of an overall health policy focusing on adolescent health. How is this policy implemented on a regional level? Is there coherence between actions undertaken within the same region? How do the various actors, elected officials, professionals, young people and families work together? A survey was conducted in the Lorraine region involving 217 people with a framework utilising both individual and group interviews. All categories of actors and stakeholders were represented. The results of this work demonstrate an often negative representation settings, and a partition of different approaches. Given that a variety of activities and actions exist, they are most often thematic. There undoubtedly remains a need to create links and build bridges between all of the projects carried out and to define in a more precise manner the common objectives focused on the health of young people.


Subject(s)
Child Welfare , Health Policy , Policy Making , Child , Child, Preschool , Family Relations , France , Health Surveys , Humans , Interinstitutional Relations , Politics
12.
Acta Paediatr ; 91(4): 466-74, 2002.
Article in English | MEDLINE | ID: mdl-12061365

ABSTRACT

UNLABELLED: The objective of this study was to determine adolescents' attitudes concerning the use of self-care and traditional medicines. A self-administered anonymous questionnaire with open-ended questions was completed by 543 adolescents aged 15-19 y. The results showed that the most frequent self-care activity for general health problems, in more than three-quarters of them, was self-medication; 14% of them resorted to minor home treatment such as taking care of wounds, bandaging or massages. Instructions for use were mentioned by 69% of adolescents as a way of choosing self-prescribed drugs. Natural medicines were used by 32% of the girls and 23% of the boys, mainly herbal teas or plant-based medicines, followed by homoeopathy. Self-care for emotional and relational problems mainly involved thinking about the problem and questioning themselves about their own behaviour or about the way they are. They also mentioned activities such as sports, going out, listening to music, watching television, and trying to think about something else by keeping themselves occupied. Natural medicines were used by 19% of the girls and 13% of the boys. Plant-based medicines or herbal teas were used most often, followed by drugs or alcohol, with homoeopathy in third place. CONCLUSION: Self-care and alternative medicines were used by adolescents in this study for physical as well as for emotional or relational problems. Their use did not reflect dissatisfaction with physicians and hospital treatment or an objection to formal services, but rather was a choice of these approaches for their own specific characteristics. They were also viewed as being less harmful than conventional treatment.


Subject(s)
Attitude , Complementary Therapies/statistics & numerical data , Health Behavior , Self Care/psychology , Adolescent , Female , France , Humans , Male , Self Medication
13.
Sante Publique ; 14(4): 371-87, 2002 Dec.
Article in French | MEDLINE | ID: mdl-12737085

ABSTRACT

The representations that youth have of health professionals and young people's demands in terms of the operation and administration of services create an original and complex problematic. Clearly, this originality implies the important differences from one culture to another. For this very reason, it seemed that a comparative study relating the representations and attitudes confronted when care is sought by young people from countries with different cultural contexts would assist in comprehending why adolescents have such particular ways of using--or not using--formal and self-administered health services. An original open-ended response questionnaire was jointly designed and validated by a French and Chilean team. A mutually agreed upon sample of 957 school children, adolescents aged from 14 to 19, participated in the study in France and in Chili. The following correlations were found. In the event of a sleeping problem (or other general worry that is physically manifested), the mother is the privileged confidant, and in the specific case of a relationship or emotional problem, it is usually one of the adolescents' friends. The general practitioner is the favoured professional person in the event of a purely physical problem. When confronted with an emotional problem, one-third of adolescents say that they would not consider going to a consultation. The expectations of the French toward health professionals are more often within the "emotional" arena than those of the Chileans which generally concern the "medical/technical" field. The practice of self-administered care is qualitatively similar but the French prefer taking medication whereas the Chileans prefer the "little home remedies". The use of natural medicine is more widespread among young Chileans, but the types of medicine used are similar, namely herbal teas and other plant-based remedies and homeopathy. These results have a variety of implications, especially in terms of the need for training health professionals in the consideration of emotional and relationship problems. It is desirable that the official health care sector considers the care delivered outside of it as being complementary resources, which respond to the adolescents' need for autonomy, and then integrate those contributions into its own area of financial responsibility.


Subject(s)
Adolescent Health Services/standards , Attitude to Health , Health Personnel , Professional-Patient Relations , Adolescent , Adolescent Health Services/statistics & numerical data , Adult , Chile/ethnology , Emotions , Female , France/ethnology , Health Care Surveys , Humans , Male
14.
J Agric Food Chem ; 49(11): 5092-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714287

ABSTRACT

A novel and simple method for the determination of some pesticide residues in strawberries using both focused microwave-assisted extraction (FMAE) and solid-phase micro extraction (SPME), coupled with high-performance liquid chromatography (HPLC), has been developed. The pesticides were first extracted from strawberries with water and the assistance of focused microwaves at 30 W for 7 min. Then, an aliquot of the resulting aqueous extract was subjected to SPME with a 60-microm thick poly(dimethylsiloxane)/divinylbenzene (PDMS/DVB) fiber for 45 min at room temperature, with the solution being stirred at 1000 rpm. The extracted pesticides on the SPME fiber were desorbed into the SPME/HPLC interface for quantitative analysis with a diode array detector (DAD). The whole sample pretreatment procedure before chromatographic analysis did not use any organic solvents or involve any blending or centrifugation steps. The five compounds (carbendazim, diethofencarb, azoxystrobine, napropamide, and bupirimate) were chosen because they cannot be analyzed easily by GC. The efficiency of this relatively fast procedure was comparable to that of previously reported methods, with detection limits at low microg/kg levels and linear responses in the range from 0.05 to 1 mg/kg of pesticide in strawberries, with RSDs between 3 and 7.3%, depending on the analyte. In all but one case results obtained by this method for field-incurred samples were comparable to those obtained with traditional methods.


Subject(s)
Chromatography, High Pressure Liquid/methods , Fruit/chemistry , Pesticide Residues/isolation & purification , Microwaves , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
15.
J Med Chem ; 44(18): 2990-3000, 2001 Aug 30.
Article in English | MEDLINE | ID: mdl-11520208

ABSTRACT

Using a solution-phase parallel synthesis strategy, a series of non-peptide somatostatin analogues were prepared, and their binding affinities to the five human somatostatin receptor subtypes (sst(1-5)) were determined. Imidazolyl derivatives 2 were found to bind with moderate affinity but with high selectivity to the sst(3) receptor subtype. Further modifications of these structures led to a more potent class of ligands, the tetrahydro-beta-carboline derivatives 4. Among these, compounds 4k (BN81644) and 4n (BN81674) bind selectively and with high affinity to the sst(3) receptor subtype (K(i) = 0.64 and 0.92 nM, respectively). Furthermore, 4k and 4n reverse the inhibition of cyclic AMP accumulation induced by 1 nM somatostatin via sst(3) receptors, with IC(50) = 2.7 and 0.84 nM, respectively. The most potent compound 4n was shown to be a competitive antagonist of human sst(3) receptors by increasing the EC(50) of SRIF-14-mediated inhibition of cAMP accumulation with a K(B) of 2.8 nM (where K(B) is the concentration of antagonist that shifts the agonist dose-response 2-fold). These new derivatives are, to our knowledge, the first potent and highly selective non-peptide human sst(3) antagonists known and, as such, are useful tools for investigating the physiological role of sst(3) receptors.


Subject(s)
Carbolines/chemical synthesis , Receptors, Somatostatin/antagonists & inhibitors , Somatostatin/analogs & derivatives , Somatostatin/chemical synthesis , Animals , CHO Cells , Carbolines/chemistry , Carbolines/metabolism , Carbolines/pharmacology , Cricetinae , Cyclic AMP/biosynthesis , Humans , Ligands , Radioligand Assay , Receptors, Somatostatin/metabolism , Somatostatin/chemistry , Somatostatin/pharmacology , Structure-Activity Relationship
17.
Sante Publique ; 12(3): 343-54, 2000 Sep.
Article in French | MEDLINE | ID: mdl-11142195

ABSTRACT

A cross-cultural study, in Chile and in France, has been held in order to compare care utilisation strategies used by teenagers and youths in two different contexts: self-administered cares, family cares, official or non-official professional cares. It has been decided to use a questionnaire with open-answers for collecting data on views and practices. Tool building and validation process, realised with both French and Chilean teams, has enabled to work with an original questionnaire, with good reproducibility of answers and very good acceptability. This tool can be used in other cultural contexts.


Subject(s)
Adolescent Behavior , Adolescent Health Services/statistics & numerical data , Attitude to Health , Cross-Cultural Comparison , Adolescent , Chile , Family , Family Health , France , Health Behavior , Health Knowledge, Attitudes, Practice , Health Services/classification , Health Services/statistics & numerical data , Humans , Self Care , Surveys and Questionnaires
18.
Oncogene ; 18(29): 4211-23, 1999 Jul 22.
Article in English | MEDLINE | ID: mdl-10435634

ABSTRACT

Loss of telomeric repeats during cell proliferation could play a role in senescence. It has been generally assumed that activation of telomerase prevents further telomere shortening and is essential for cell immortalization. In this study, we performed a detailed cytogenetic and molecular characterization of four SV40 transformed human fibroblastic cell lines by regularly monitoring the size distribution of terminal restriction fragments, telomerase activity and the associated chromosomal instability throughout immortalization. The mean TRF lengths progressively decreased in pre-crisis cells during the lifespan of the cultures. At crisis, telomeres reached a critical size, different among the cell lines, contributing to the peak of dicentric chromosomes, which resulted mostly from telomeric associations. We observed a direct correlation between short telomere length at crisis and chromosomal instability. In two immortal cell lines, although telomerase was detected, mean telomere length still continued to decrease whereas the number of dicentric chromosomes associated was stabilized. Thus telomerase could protect specifically telomeres which have reached a critical size against end-to-end dicentrics, while long telomeres continue to decrease, although at a slower rate as before crisis. This suggests a balance between elongation by telomerase and telomere shortening, towards a stabilized 'optimal' length.


Subject(s)
Cell Transformation, Neoplastic/genetics , Cell Transformation, Viral/genetics , Fibroblasts/metabolism , Telomerase/metabolism , Telomere/metabolism , Cell Line, Transformed , Cell Transformation, Neoplastic/metabolism , Centromere , Chromosome Aberrations , Chromosomes, Human/genetics , Chromosomes, Human/ultrastructure , Fibroblasts/cytology , Humans , Image Processing, Computer-Assisted , In Situ Hybridization, Fluorescence , Metaphase , Recombinant Fusion Proteins/physiology , Simian virus 40/genetics , Simian virus 40/physiology , Transfection
19.
J Mol Biol ; 284(2): 435-47, 1998 Nov 27.
Article in English | MEDLINE | ID: mdl-9813128

ABSTRACT

The periplasmic trimethylamine N-oxide (TMAO) reductase from the marine bacteria Shewanella massilia is involved in a respiratory chain, having trimethylamine N-oxide as terminal electron acceptor. This molybdoenzyme belongs to the dimethyl sulfoxide (DMSO) reductase family, but has a different substrate specificity than its homologous enzyme. While the DMSO reductases reduce a broad spectra of organic S-oxide and N-oxide compounds, TMAO reductase from Shewanella massilia reduces only TMAO as the natural compound. The crystal structure was solved by molecular replacement with the coordinates of the DMSO reductase from Rhodobacter sphaeroides. The overall fold of the protein structure is essentially the same as the DMSO reductase structures, organized into four domains. The molybdenum coordination sphere is closest to that described in the DMSO reductase of Rhodobacter capsulatus. The structural differences found in the protein environment of the active site could be related to the differences in substrate specificity of these enzymes. In close vicinity of the molybdenum ion a tyrosine residue is missing in the TMAO reductase, leaving a greater space accessible to the solvent. This tyrosine residue has contacts to the oxo groups in the DMSO reductase structures. The arrangement and number of charged residues lining the inner surface of the funnel-like entrance to the active site, is different in the TMAO reductase than in the DMSO reductases from Rhodobacter species. Furthermore a surface loop at the top of the active-site funnel, for which no density was present in the DMSO reductase structures, is well defined in the oxidized form of the TMAO reductase structure, and is located on the border of the funnel-like entrance of the active center.


Subject(s)
Coenzymes , Gram-Negative Facultatively Anaerobic Rods/enzymology , Metalloproteins/chemistry , Oxidoreductases, N-Demethylating/chemistry , Pteridines/chemistry , Amino Acid Sequence , Catalytic Domain , Computer Simulation , Crystallography, X-Ray , Models, Molecular , Molecular Sequence Data , Molybdenum Cofactors , Sequence Homology, Amino Acid
20.
J Biol Chem ; 273(26): 16615-20, 1998 Jun 26.
Article in English | MEDLINE | ID: mdl-9632735

ABSTRACT

Reduction of trimethylamine N-oxide (TMAO) in Escherichia coli involves the terminal molybdoreductase TorA, located in the periplasm, and the membrane anchored c type cytochrome TorC. In this study, the role of the TorD protein, encoded by the third gene of torCAD operon, is investigated. Construction of a mutant, in which the torD gene is interrupted, showed that the absence of TorD protein leads to a two times decrease of the final amount of TorA enzyme. However, specific activity and biochemical properties of TorA enzyme were similar to those of the enzyme produced in the wild type. Excess of TorD protein restores the normal level of TorA enzyme, and also, leads to the appearance of a new cytoplasmic form of TorA on SDS-polyacrylamide gel electrophoresis using gentle conditions. This probably indicates a new folding state of the cytoplasmic TorA protein when TorD is overexpressed. BIAcore techniques demonstrated direct specific interaction between the TorA and TorD proteins. This interaction was enhanced when TorA was previously unfolded by heating. Finally, as TorA is a molybdoenzyme, we demonstrated that TorD can interact with TorA before the molybdenum cofactor has been inserted. As TorD homologue encoding genes are found in various TMAO reductase loci, we propose that TorD is a chaperone protein specific for the TorA enzyme. It belongs to a family of TorD-like chaperones present in several bacteria, and, probably, involved in TMAO reductase folding.


Subject(s)
Bacterial Proteins/metabolism , Escherichia coli Proteins , Escherichia coli/metabolism , Molecular Chaperones/metabolism , Oxidoreductases, N-Demethylating/metabolism , Protein Folding , Amino Acid Sequence , Cytoplasm/metabolism , Heme/metabolism , Methylamines/metabolism , Molecular Sequence Data , Sequence Alignment , Transcription, Genetic
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