Biomedical subjects

M Bonnet

Publications and source records attributed to M Bonnet.

At least 19 recordsLinked to original sources

PubMed2006

Long-term efficacy and cost-effectiveness of polyethylene glycol 3350 plus electrolytes in chronic constipation: a retrospective study in a disabled population.

OBJECTIVES: The efficacy and safety of treatments for constipation in severely intellectually disabled patients and their associated cost-effectiveness are an under-investigated area of clinical practice. Aiming to address this, the objectives of the study were to evaluate the efficacy and tolerability of polyethylene glycol 3350 plus electrolytes (Movicol; PEG+E) by comparing clinical data collected before and after its introduction to a stable population of residents of a mental health care, long-stay institution. The study also attempted an economic evaluation of the use of PEG+E in this setting. RESEARCH DESIGN AND METHODS: This was a retrospective study of 54/66 severely intellectually and physically disabled residents of a specialist unit at La Milétrie University Hospital, Poitiers, France, who suffered regularly from constipation. A total of 54 residents were treated with PEG+E (1-3 sachets a day) for 24 months. The number of stools, episodes of diarrhoea (defined as frequent stools, not necessarily watery), body weights and blood biochemistry were recorded. Data were compared with those recorded during the 21 months preceding the introduction of PEG+E for 16/54 residents who had been treated regularly with a range of other interventions for the relief of constipation. The monthly use and costs of laxatives, enemas and suppositories was obtained from hospital pharmacy records, and the total hospital costs before and after the introduction of PEG+E treatment was calculated. RESULTS: The mean (+/- standard deviation) number of stools per patient per month was significantly greater following the introduction of PEG+E (24.9 +/- 6.3) compared to before its use (12.4 +/- 3.4) (p < 0.001). The mean (+/- standard deviation) monthly number of episodes of diarrhoea per patient before and after the introduction of PEG+E was 0.1 +/- 0.1 and 6.3 +/- 2.9, respectively (p < 0.001). Treatment with PEG+E was not associated with adverse effects on body weight or blood biochemistry values. Introduction of PEG+E and its increasing use reduced the total hospital medical ward expenditure on laxatives from 3788 to 1767 Euros per month. CONCLUSIONS: PEG+E is effective in the clinical management of constipation in an institutional setting. Furthermore, long-term intensive therapy with PEG+E was not associated with adverse effects on body weight or blood biochemistry values. Although the time periods over which the economic data and the efficacy and safety data were collected did not directly correspond, this study indicates that use of PEG+E in the management of constipation in people with severe intellectual disability may be cost-effective, reducing hospital laxative costs.

Adult↗

PubMed2006

Effects of quantitative trait loci on chromosomes 1, 2, 4, and 7 on growth, carcass, and meat quality traits in backcross Meishan x Large White pigs.

The aim of this work was to estimate whether genetic dissection of QTL on chromosomes 1, 2, 4, and 7, detected in an F2 Meishan x Large White population, can be achieved with a recombinant back-cross progeny test approach. For this purpose, a first generation of backcross (BC1) was produced by using frozen semen of F1 Large White x Meishan boars with Large White females. Four BC1 boars were selected because of their heterozygosity for at least 1 of the 4 regions. The BC1 boars were crossed with Large White sows, and the resulting BC2 offspring were measured for several growth and body composition traits. Contrary to the F2 animals, BC2 animals were also measured for meat quality traits in adductor, gluteus superficialis (GS), longissimus dorsi, and biceps femoris (BF) muscles. Each BC1 boar was tested for a total of 39 traits and for the 4 regions with statistical interval mapping analyses. The QTL effects obtained in BC1 families showed some differences compared with those described in F1 families. However, we confirmed QTL effects for growth in the SW1301-SW2512 markers interval on chromosome 1 and also for body composition in the SW1828-SW2512 markers interval on chromosome 1, in the SW2443-SWR783 markers interval on chromosome 2, and in the SW1369-SW632 markers interval on chromosome 7. In addition, we detected new QTL for growth traits on chromosome 2 and for meat quality traits on chromosomes 1 and 2. Growth of animals from weaning to the end of the test was influenced by the IGF2 gene region on chromosome 2. Concerning meat quality, ultimate pH of adductor, longissimus dorsi, and BF were affected by the interval delimited by UMNP3000 and SW2512 markers on chromosome 1, and a* of GS, L* of BF, and water-holding capacity of GS were affected by QTL located between marker loci SW2443 and SWR783 on chromosome 2. Recombinant progeny testing appeared to be a suitable strategy for the genetic dissection of the QTL investigated.

Adipose Tissue↗

PubMed2005

Leptin expression in ruminants: nutritional and physiological regulations in relation with energy metabolism.

Leptin, mainly produced in adipose tissue (AT), is a protein involved in the central and/or peripheral regulation of body homeostasis, energy intake, storage and expenditure, fertility and immune functions. Its role is well documented in rodent and human species, but less in ruminants. This review is focused on some intrinsic and extrinsic factors which regulate adipose tissue leptin gene expression and leptinemia in cattle, sheep, goat and camel: age, physiological status (particularly pregnancy and lactation) in interaction with long-term (adiposity) and short-term effects of feeding level, energy intake and balance, diet composition, specific nutrients and hormones (insulin, glucose and fatty acids), and seasonal non-dietary factors such as photoperiod. Body fatness strongly regulates leptin and its responses to other factors. For example, leptinemia is higher after underfeeding or during lactation in fat than in lean animals. Physiological status per se also modulates leptin expression, with lactation down-regulating leptinemia, even when energy balance (EB) is positive. These results suggest that leptin could be a link between nutritional history and physiological regulations, which integrates the animal's requirements (e.g., for a pregnancy-lactation cycle), predictable food availability (e.g., due to seasonal variations) and potential for survival (e.g., body fatness level). Reaching permissive leptin thresholds should be necessary for pubertal or postpartum reproductive activity. In addition to the understanding of leptin yield regulation, these data are helpful to understand the physiological significance of changes in leptin secretion and leptin effects, and how husbandry strategies could integrate the adaptative capacities of ruminant species to their environment.

Adipose Tissue↗

PubMed2005

Pregnancy increases plasma leptin in nulliparous but not primiparous goats while lactation depresses it.

Most dairy ruminants are still lactating during early pregnancy, which could induce hormonal adaptations different from those observed during pregnancy alone. The incidence of concomitant lactation and pregnancy on plasma leptin has not been studied, and physiological factors involved in its regulation have not been addressed in goats. We assayed leptinemia throughout the pregnancy-lactation cycle in nulliparous and primiparous goats, starting 165 days prior to parturition and finishing 59 days after. During the first half of pregnancy, primiparous goats were lactating. Lactating non-pregnant primiparous goats were studied in parallel. Plasma leptin increased (+49%) up to mid-pregnancy in nulliparous, but not in primiparous goats. Furthermore, leptinemia was similar between pregnant and non-pregnant lactating primiparous goats, suggesting a strong leptinemia down-regulation by late lactation. Plasma leptin decreased from mid-pregnancy to parturition, more markedly in nulliparous goats, and remained depressed during early lactation at a similar level in both female types. It was lower, at 130 days of pregnancy, in goats carrying two fetuses. The leptinemia down-regulation by late pregnancy was highlighted by the lack of plasma leptin increase after drying-off late-pregnant primiparous goats, while it strongly increased in non-pregnant goats. The observation of leptinemia increase only in nulliparous goats suggests that it is not an essential endocrine adaptation during early pregnancy. By contrast, in both female types, the low leptinemia during transition from late pregnancy to lactation, and during late lactation, may be important for the adaptations that occur during lactation such as the partitioning of energy and nutrients towards essential functions and/or hyperphagia.

Animals↗

PubMed2005

Acid-tolerant Listeria monocytogenes persist in a model food system fermented with nisin-producing bacteria.

AIMS: To investigate the induction of the acid tolerance response (ATR) in Listeria monocytogenes and to assess the persistence of the pathogen in broth fermented using a nisin-producing starter culture. METHODS AND RESULTS: Lactic, acetic and hydrochloric acids were used to induce the ATR in L. monocytogenes growing at early exponential phase. Cells were then challenged in medium acidified to pH 3.5 with the same acid. Only lactic acid induced a detectable ATR. ATR+ cells maintained their initial numbers after 1 h exposure while ATR- were reduced by c. 4 log10 CFU. ATR+ or ATR- cells were also inoculated in M17G broth fermented with nisin-producing (nis+) or control (nis-) Lactococcus lactis. When exposed to nisin, the numbers of ATR+ cells were c. 2 log10 CFU higher than non detectable ATR- cells at day 3. In the absence of nisin (nis- culture), L. monocytogenes was recovered from all ATR+ and ATR- samples after 30 days. In contrast, no L. monocytogenes were recovered from any nis+ATR- samples but four of five nis+ATR+ samples were positive for L. monocytogenes after 30 days. CONCLUSIONS: The ATR confers cross-resistance to nisin for at least 30 days in a system fermented by nisin-producing bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: The cross-resistance induced by the ATR should be considered for the safety of foods fermented with bacteriocin-producing cultures.

Adaptation, Physiological↗

PubMed2005

Cognitive impairment as marker of diffuse brain abnormalities in early relapsing remitting multiple sclerosis.

OBJECTIVES: To establish the frequency of cognitive impairment in a population based sample of patients with recently diagnosed relapsing-remitting multiple sclerosis (RRMS), and to determine the relation between cognitive abnormalities and the extent of macroscopic and microscopic tissue damage revealed by magnetic resonance imaging (MRI) and magnetisation transfer (MT) imaging. METHODS: 58 patients with RRMS consecutively diagnosed in the previous six months in Aquitaine and 70 healthy controls underwent a battery of neuropsychological tests. Lesion load and atrophy indices (brain parenchymal fraction and ventricular fraction) were measured on brain MRI. MT ratio (MTR) histograms were obtained from lesions, normal appearing white matter (NAWM), and normal appearing grey matter (NAGM). Gadolinium enhanced lesions were counted. RESULTS: 44 RRMS patients could be individually matched with healthy controls for age, sex, and education. Patients performed worse in tests of verbal and spatial memory, attention, information processing speed, inhibition, and conceptualisation. Measures of attention and information processing speed were correlated with lesion load, mean NAWM MTR, and the peak location of the NAGM MTR histogram in the patients. Multivariate regression analysis showed that lesion load and mean NAWM MTR were among the MR indices that were most significantly associated with impairment of attention and information processing speed in these early RRMS cases. CONCLUSIONS: Cognitive impairment appears to be common in the early stages of RRMS, mainly affecting attention, information processing speed, memory, inhibition, and conceptualisation. The severity of these deficits reflects the extent of the lesions and the severity of tissue disorganisation outside lesions.

Adult↗

PubMed2005

Perioperative cerebral ischaemia in cardiac surgery and BIS.

A 46-year-old woman was monitored by bispectral index monitoring (BIS) during redo aortic and mitral valve replacement. On release of the aortic cross clamp there was a sudden, severe, unexplained, and sustained fall in the BIS value. Postoperatively, a CT scan was consistent with multiple ischaemic lesions. The lesions were presumed to be due to air embolism. This case suggests that a sudden unexplained and persistent fall in BIS may indicate cerebral ischaemia.

Brain↗

PubMed2005

Does one size fit all? Drug resistance and standard treatments: results of six tuberculosis programmes in former Soviet countries.

SETTING: After the collapse of the Soviet Union, countries in the region faced a dramatic increase in tuberculosis cases and the emergence of drug resistance. OBJECTIVE: To discuss the relevance of the DOTS strategy in settings with a high prevalence of drug resistance. DESIGN: Retrospective analysis of one-year treatment outcomes of short-course chemotherapy (SCC) and results of drug susceptibility testing (DST) surveys of six programmes located in the former Soviet Union: Kemerovo prison, Russia; Abkhasia, Georgia; Nagorno-Karabagh, Azerbaijan; Karakalpakstan, Uzbekistan; Dashoguz Velayat, Turkmenistan; and South Kazakhstan Oblast, Kazakhstan. Results are reported for new and previously treated smear-positive patients. RESULTS: Treatment outcomes of 3090 patients and DST results of 1383 patients were collected. Treatment success rates ranged between 87% and 61%, in Nagorno-Karabagh and Kemerovo, respectively, and failure rates between 7% and 23%. Any drug resistance ranged between 66% and 31% in the same programmes. MDR rates ranged between 28% in Karakalpakstan and Kemerovo prison and 4% in Nagorno-Karabagh. CONCLUSION: These results show the limits of SCC in settings with a high prevalence of drug resistance. They demonstrate that adapting treatment according to resistance patterns, access to reliable culture, DST and good quality second-line drugs are necessary.

Antitubercular Agents↗

PubMed2003

Error negativity on correct trials: a reexamination of available data.

The error negativity, an EEG wave observed when subjects commit an error in a choice reaction time (RT) task, is often considered as a sign of error detection. Recently, reports of Ne-like waves on correct responses did challenge this interpretation. It has been proposed, however, that these Ne-like waves result either from an artifactual contamination of response-locked activities by stimulus-locked ones, or from an implicit monitoring of the time elapsing during the RT. Our aim was to reprocess published data: (1) to compare the shape and amplitude of EMG-locked and stimulus-locked ERPs on correct trials, and (2) to compare the size of the EMG-locked Ne-like waves obtained on fast and slow trials. The results neither support the artifact hypothesis nor the RT monitoring one. Therefore, it seems that the Ne-like waves observed on correct trials do correspond to a Ne, which suggests that the Ne has a broader significance than just error detection.

Adult↗

PubMed2003

[Perioperative management of ventricular assist devices].

OBJECTIVE: To review the perioperative anaesthetic management of ventricular assist devices. DATA SOURCES: Extraction from Pubmed database of french and english articles on the perioperative anaesthetic management of ventricular assist devices for 15 years. DATA SELECTION: The collected articles were reviewed and selected according to their quality and originality. The more recent data were selected. DATA SYNTHESIS: Cardiac transplantation is an effective treatment for patients in end stage cardiac failure, but the average waiting time of 17 months, associated with the lack of organs (357 out of 832 candidates were transplanted in 1996) results in a high number of deaths in patients awaiting transplantation. The appearance in the 1980's, of the first ventricular assist device (VAD) provided a new possibility for the management of patients with end-stage cardiac failure awaiting transplantation ("bridge to transplant"). The perioperative anaesthetic management of these patients is complex. End stage cardiac failure, poorly responsive to pharmacological interventions, results rapidly in secondary organ dysfunctions. VADs produce a rapid improvement in haemodynamic, renal, hepatic and neuro-endocrine functions over a 2 months period, allowing transplantation to take place under optimal conditions. However VADs are not without complications (1 year mortality of 20%), of which the major are: infections (40%), perioperative haemorrhage (30%) and thrombo-embolic sequelae (30%). A best knowledge of pathophysiology of these complications is necessary to an optimal management of patients with ventricular assist devices.

Anesthesia↗

PubMed2002

Activation of the supplementary motor area and of attentional networks during temporal processing.

This paper first provides a survey of the expanding brain imaging literature in the field of time processing, showing that particular task features (discrete vs rhythmic, perceptual vs motor) do not significantly affect the basic pattern of activation observed. Next, positron emission tomography (PET) data obtained in a timing task (temporal reproduction) with two distinct duration ranges (2.2--3.2 and 9--13 s) are reported. The stimuli consisted of vibrations applied to the subject's right middle finger. When the vibration ended, the subject estimated an interval identical to its length before pressing a response button. The control task used cued responses with comparable intervals and stimuli. The pattern of activation obtained in the timing task as compared to control mainly included areas having attentional functions (the right dorsolateral prefrontal, inferior parietal, and anterior cingulate cortices), and the supplementary motor area (SMA). No significant difference was seen as a function of the duration range. It is argued, firstly, that involvement of the attentional areas derives from specific relations between attention and the temporal accumulator, as described by dominant timing models; and, secondly, that the SMA, or more probably one of its subregions, subserves time processing.

Adult↗

PubMed2002

Leptin expression in the ovine mammary gland: putative sequential involvement of adipose, epithelial, and myoepithelial cells during pregnancy and lactation.

We examined the ability of the ovine mammary gland to synthesize leptin throughout pregnancy and lactation. Leptin gene expression was assayed by real-time reverse transcription and polymerase chain reaction in mammary gland from ewes at 15, 80, 106, 112, or 141 d of pregnancy and at 0 (30 min after parturition), 3, 48, or 70 d of lactation. Leptin mRNA level was high at the beginning (the first 80 d) and at the end of pregnancy and was lower at mid-pregnancy and throughout lactation. Furthermore, during these periods of mammary leptin expression, the location of leptin protein, as determined by immunohistochemical analysis, changed within mammary tissue. It was located in adipose cells during early stages of pregnancy, in epithelial cells after full cell differentiation just before parturition, and in myoepithelial cells after parturition. These data, compared with published data on leptin receptor gene expression, provide evidence that leptin could be produced by different cell types of the mammary gland and could act as a paracrine factor on mammary cell growth and differentiation via adipose-epithelial cells and myoepithelial-epithelial cell interactions.

Adipocytes↗

PubMed2002

[Bilateral keratoconus: a case report].

Among corneal dystrophies, the keratoconus is one of the most frequently observed among young adults. A clinico pathological case is reported in a 13-year-old-girl of African origin. The diagnosis of bilateral keratoconus was established based on the obvious changes of the corneal curvature and thickness. After an unsuccessful attempt to improve vision with contact lenses, a keratoplasty was finally performed on one side to remove the pathological cornea. Its histopathological study found the characteristic changes of keratoconus: breaks of Bowman's layer and corneal thinning.

Adolescent↗

PubMed2001

A fluorescent reverse transcription-polymerase chain reaction assay to quantify the lipoprotein lipase messenger RNA.

Relative quantitative reverse transcription-polymerase chain reaction (rqRT-PCR), which allows an accurate quantification of the amount of mRNA in samples potentially differing in the quality of their RNA preparation, was used to quantify lipoprotein lipase (LPL) mRNA in ovine adipose tissue. A comparative evaluation of four rqRT-PCR procedures was carried out. The amount of LPL mRNA was assayed relative to either that of gamma-actin (ACT) or cyclophilin (CYC) mRNA, used as endogenous standard. Independent (INACT and INCYC procedures) or simultaneous (COACT and COCYC procedures) amplifications have been compared. Fluorescently labelled primers yielded PCR products which were quantitatively analysed using an automated DNA sequencer. After optimizing the PCR cycle number and verifying that the amounts of ACT and CYC mRNA varied only weakly according to the nutritional conditions studied, we have tested the ability of the four procedures to quantify specific variations in LPL mRNA. The repeatability of each step and the overall assay reproducibility were also examined. The COACT and INCYC procedures were finally retained to accurately quantify LPL mRNA in AT from nine underfed or refed ewes, and gave highly correlated results (r=0.98, p<0.01). In addition, significant correlations (r=0.83, p<0.01 and r=0.92, p<0.01 for COACT and INCYC, respectively) were observed with the LPL activity in AT.

Actins↗

PubMed2001

Deficit in motor cortical activity for simultaneous bimanual responses.

Reaction time (RT) is known to be longer for simultaneous bimanual responses than for unimanual ones. This phenomenon is called "bilateral deficit". To identify the mechanisms subserving the bilateral deficit, brain electrical activity was examined, with a source derivation method, in 12 right-handed subjects, during the preparation and execution periods of a RT task. The responses were either unilateral or bilateral index finger flexion, performed either in a simple RT condition, with 20% catch trials, or in a choice RT condition. A deficit was observed in RT for the bilateral response for the right-index finger movement. In cerebral electrical activities, no evidence of a correlate of a bilateral deficit was found during the preparatory period. Conversely, during the execution period, an EEG correlate of the bilateral deficit was found. For the right hand, the activation of the sensorimotor area directly involved in the voluntary control was weaker for bilateral than for unilateral contralateral responses. The reasons for such a bilateral command weakness are discussed in the context of our RT task. First, the constraint of synchronisation included in the bilateral response might require an interhemispheric information transmission that resulted in a braking effect. Second, given that an ipsilateral inhibition is present in case of choice between the two hands of one particular unimanual response, and given that this ipsilateral inhibition is also present in case of simple unimanual trials, we hypothesise that a mutual transcallosal inhibitory effect also persists in the bilateral response.

Adult↗

PubMed2001

Leptin in ruminants. Gene expression in adipose tissue and mammary gland, and regulation of plasma concentration.

This paper reviews data on leptin gene expression in adipose tissue (AT) and mammary gland of adult ruminants, as well as on plasma leptin variations, according to genetic, physiological, nutritional and environmental factors. AT leptin mRNA level was higher in sheep and goat subcutaneous than visceral tissues, and the opposite was observed in cattle; it was higher in fat than in lean selection line in sheep; it was decreased by undernutrition and increased by refeeding in cattle and sheep, and not changed by adding soybeans to the diet of lactating goats; it was increased by injection of NPY to sheep, and by GH treatment of growing sheep and cattle. Insulin and glucocorticoids in vitro increased AT leptin mRNA in cattle, and leptin production in sheep. Long daylength increased AT lipogenic activities and leptin mRNA, as well as plasma leptin in sheep. Mammary tissue leptin mRNA level was high during early pregnancy and was lower but still expressed during late pregnancy and lactation in sheep. Leptin was present in sheep mammary adipocytes, epithelial and myoepithelial cells during early pregnancy, late pregnancy and lactation, respectively. Plasma leptin in cattle and sheep was first studied thanks to a commercial "multi-species" kit. It was positively related to body fatness and energy balance or feeding level, and decreased by beta-agonist injection. The recent development of specific RIA for ruminant leptin enabled more quantitative study of changes in plasma leptin concentration, which were explained for 35--50% by body fatness and for 15--20% by feeding level. The response of plasma leptin to meal intake was related positively to glycemia, and negatively to plasma 3-hydroxybutyrate. The putative physiological roles of changes in leptin gene expression are discussed in relation with published data on leptin receptors in several body tissues, and on in vivo or in vitro effects of leptin treatment.

Adipose Tissue↗

PubMed2001

[Epileptogenic drugs in anesthesia].

Most anaesthetics and analgesics have both pro- and anticonvulsant activity. The data in the literature should be analysed with respect to the patient population, the recording of epileptic activity and the method of EEG analysis. Among inhaled anaesthetics, isoflurane has strong anticonvulsant properties. In some circumstances, sevoflurane may induce an epileptic activity. With the exception of ketamine and etomidate, all intravenous hypnotics may be used for anesthesia of the epileptic patient. Midazolam is a potent anticonvulsant. Among narcotics, fentanyl and alfentanil may induce clinical or electroencephalographic seizures. Considering the large number of patients treated with these agents without any neurological adverse effect, the clinical relevance of these data is unclear. Neuromuscular blocking agents do not possess pro- or anticonvulsant properties.

Anesthetics↗

PubMed2001

Effects of photoperiod and feeding level on adipose tissue and muscle lipoprotein lipase activity and mRNA level in dry non-pregnant sheep.

The aim of the present study was to investigate the effects of photoperiod and feeding level on lipid metabolism in ovine perirenal and subcutaneous adipose tissues (AT) and in skeletal and cardiac muscles. Twenty dry non-pregnant ovariectomised ewes were divided into two groups and subjected to either 8 h or 16 h light/d, and underfed at 22 % energy requirements for 7 d. Half of the ewes in each group were slaughtered and the remaining ewes were refed at 190 % energy requirements for 14 d, until slaughtering. Refeeding increased (2.6-4.3-fold) malic enzyme (ME), fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH) and glycerol-3-phosphate dehydrogenase (G3PDH) activities in subcutaneous AT as well as lipoprotein lipase (LPL) activity in perirenal (3.5-fold) and subcutaneous (10-fold) AT and to a lesser extent (1.4-fold) in the skeletal longissimus thoracis and cardiac muscles. Moreover, variations of LPL mRNA level followed variations of LPL activity: refeeding increased perirenal AT- and cardiac muscle-mRNA levels (7.4- and 2-fold respectively). The main finding of this study is that, for a given level of food intake, long days (compared with short days) increased the LPL activity in the longissimus thoracis muscle and, in refed ewes, the activities of LPL and ME in subcutaneous AT. Furthermore, long days increased LPL mRNA level in cardiac muscle and perirenal AT. Thus, our results show that there are direct effects of photoperiod on sheep AT lipogenic potential, as well as on muscle LPL activity, which are not caused by changes in nutrient availability.

Adipose Tissue↗