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C Roux

Publications and source records attributed to C Roux.

At least 37 records · Page 2Linked to original sources
PubMed2005

Segregation of chromosomes in sperm of Robertsonian translocation carriers.

Robertsonian translocations are the most frequent structural chromosomal abnormalities in humans and can affect fertility, with various degrees of sperm alterations in men; or the pregnancy outcome of the carriers. The studies on meiotic segregation of chromosomes in sperm of Robertsonian translocation males find a majority of normal or balanced spermatozoa for the chromosomes related to the translocation (mean 85.42%; range 60-96.60%). Furthermore, recent studies suggest an interchromosomal effect. Studies on spermatozoa from translocation carriers, and in mouse models help the comprehension of the meiotic segregation mechanisms. Results of meiotic segregation analysis in man could be integrated in genetic counselling especially when assisted reproductive technology is required.

Chromosomes, Human, Pair 13↗
PubMed2005

Claviceps cyperi, a new cause of severe ergotism in dairy cattle consuming maize silage and teff hay contaminated with ergotised Cyperus esculentus (nut sedge) on the Highveld of South Africa.

During December/January 1996/97 typical summer syndrome (hyperthermia and a 30% drop in milk yield) occurred in succession in two Holstein dairy herds (n=240 and n=150 milking cows, respectively) on the South African Highveld. These farms are situated in the midst of the prime maize and dairy farming areas of South Africa where this condition had never been diagnosed before. The individual components of the concentrate on both farms were negative for ergot alkaloids. Endophytic fungi and/or ergot infestation of teff and other grasses fed to the cows were then suspected of being involved, but neither endophytes nor ergot alkaloids could be implicated from these sources. By measuring the serum prolactin levels of groups of sheep (n=5) fed the first farm's total mixed ration (TMR) or its three individual fibre components for a period of 11 days, the source of the ergot alkaloids was identified. A statistically significant decrease in the level of this hormone occurred only in the group on maize silage (which constituted 28% on dry matter base of the TMR). The involvement of the maize silage was further chemically confirmed by the high levels of total ergot alkaloids, predominantly ergocryptine, found by LC-MS in the silage as well as in the TMR (115-975 ppb and 65-300 ppb, respectively). The ergot alkaloid content (mainly ergocryptine) of the maize silage on the second affected farm was 875 ppb. Withdrawal of contaminated silage resulted in gradual recovery of stock on both farms. Nut sedge (Cyperus esculentus and Cyperus rotundus of the family Cyperaceae) has a world-wide distribution and is a common weed in annual crops, and can be parasitized by Claviceps cyperi. Careful examination of the maize silage from both farms revealed that it was heavily contaminated with nut sedge and that it contained minute sclerotia, identified as those of Claviceps cyperi, originating from the latter. Nut sedge was abundant on both farms and it is believed that late seasonal rain had resulted in mature, heavily ergotised nut sedge being cut with the silage. Claviceps cyperi sclerotia, collected on the affected fields in the following autumn contained 3600-4000 ppm ergocryptine. That the dominant alkaloid produced by this particular fungus was indeed ergocryptine, was confirmed by negative ion chemical ionization MS/MS. In one further outbreak in another Holstein herd, teff hay contaminated with ergotised nut sedge and containing 1200 ppb alkaloids, was incriminated as the cause of the condition. This is the first report of bovine ergotism not associated with the Poaceae infected with Claviceps purpureum or endophytes but with the family Cyperaceae and this particular fungal phytopathogen.

Animal Feed↗
PubMed2004

Three-dimensional X-ray absorptiometry (3D-XA): a method for reconstruction of human bones using a dual X-ray absorptiometry device.

Three-dimensional accurate evaluation of the geometry of the proximal femur may be helpful for hip fracture risk evaluation. The purpose of this study was to apply and validate a stereo-radiographic 3D reconstruction method of the proximal femur, using contours identification from biplanar DXA images. Twenty-five excised human proximal femurs were investigated using a standard DXA unit. Three-dimensional personalized models were reconstructed using a dedicated non-stereo corresponding contours (NSCC) algorithm. Three-dimensional CT-scan reconstructions obtained on a clinical CT-scan unit were defined as geometric references for the comparison protocol, in order to assess accuracy and reproducibility of the 3D stereo-radiographic reconstructions. The precision of a set of 3D geometric parameters (femoral-neck axis length, mid-neck cross-section area, neck-shaft angle), obtained from stereo-radiographic models was also evaluated. This study shows that the NSCC method may be applied to obtain 3D reconstruction from biplanar DXA acquisitions. Applied to the proximal femur, this method showed good accuracy as compared with high-resolution personalized CT-scan models (mean error = 0.8 mm). Moreover, precision study for the set of 3D parameters yielded coefficients of variation lower than 5%. This is the first study providing 3D geometric parameters from standard 2D DXA images using the NSCC method. It has good accuracy and reproducibility in the present study on cadaveric femurs. In vivo prospective studies are needed to evaluate its discriminating potential on hip fracture risk prediction.

Absorptiometry, Photon↗
PubMed2004

Seven years of treatment with risedronate in women with postmenopausal osteoporosis.

The effects of 7 years of risedronate treatment were evaluated in a second 2-year extension of a 3-year vertebral fracture study in women with osteoporosis. For the first 5 years of the study, women received risedronate 5 mg/day or placebo according to the original randomization, with maintenance of blinding. All the women who entered into the 6-7 years extension study received risedronate 5 mg/day. Endpoints included vertebral and nonvertebral fracture assessments, changes in biochemical markers of bone turnover, and bone mineral density (BMD) measurements. A total of 164 women (placebo/risedronate group, 81; risedronate group, 83) entered the 6-7 years extension study and 136 (83%) completed the study. Annualized incidence of new vertebral fractures during the 6-7 years was similar between the 2 treatment groups (3.8%). The incidence of vertebral fractures did not change in the 7-year risedronate group during the 6-7 years as compared to 4-5 years, while a significant reduction was observed in the placebo group that switched to risedronate treatment during years 6-7. The incidence of nonvertebral fractures was 7.4% and 6.0% in the placebo/risedronate and risedronate groups, respectively, during years 6-7. Urinary N-telopeptide decreased from baseline by 54% and 63% at 3 months and 7 years, respectively, in the risedronate group. The increases in BMD from baseline after 5 years of risedronate treatment were maintained or increased further during years 6-7; lumbar spine BMD after 5 and 7 years of risedronate treatment increased from baseline by 8.8% and 11.5%, respectively, for this extension study population. Risedronate was well tolerated and the occurrence of upper gastrointestinal adverse events was low. After 7 years of continuous risedronate treatment there were significant increases in BMD and decreases in bone turnover to within premenopausal levels and there was no indication of any loss of anti-fracture efficacy.

Aged↗
PubMed2004

Predictors of compliance with a home-based exercise program added to usual medical care in preventing postmenopausal osteoporosis: an 18-month prospective study.

This prospective 18-month study was designed to assess long-term compliance with a program of exercise aimed to prevent osteoporosis after an educational intervention and to uncover determinants of compliance. A total of 135 postmenopausal women were recruited by flyers or instructed by their physicians to participate in an educational session added to usual medical care. After a baseline visit and dual-energy X-ray absorptiometry, volunteers participated in a 1-day educational session consisting of a lecture and discussion on guidelines for appropriate physical activity and training in a home-based exercise program taught by a physical therapist. Scheduled follow-up visits were 1, 6, and 18 months after the educational session. Compliance with the exercise program was defined as an exercise practice rate 50% or greater than the prescribed training. The 18-month compliance rate was 17.8% (24/135). The main reason for withdrawal from the program was lack of motivation. Two variables predicted compliance: contraindication for hormone replacement therapy (odds ratio [OR] = 0.13; 95% confidence interval [95% CI], 0.04 to 0.46) and general physical function scores from an SF-36 questionnaire (OR=1.26; 95% CI, 1.03 to 1.5). To a lesser extent, osteoporosis risk, defined as a femoral T-score < or =-2.5, predicted compliance (OR=0.34; 95% CI, 0.10 to 1.16). Despite the addition of an educational session to usual medical care to inform participants about the benefits of exercise, only a minority of postmenopausal women adhered to a home-based exercise program after 18 months.

Exercise Therapy↗
PubMed2004

In vitro ultrasound measurement at the human femur.

Measurements of broadband ultrasonic attenuation (BUA) represent an established means of skeletal status assessment in osteoporosis. Today, the skeletal site that is the most widely used clinically is the calcaneus (heel bone). However, we hypothesized that fracture risk predictions could be improved if ultrasound measurements were performed directly at the main site of fracture, e.g., the proximal femur. The goal of this paper is to demonstrate in vitro the feasibility of quantitative ultra sound (QUS) imaging at the upper part of fee femur, and to investigate the relationships of BUA to bone mineral density (BMD). Forty-four excise human femurs were measured in transmission with a pair of focused 0.5-MHz central frequency transducers. Two-dimensional scans were performed, and the radio frequency (rf) signals were recorded at each measurement point. A data acceptance criterion for region of interest (ROI) selection was established based on the linearity of the frequency-dependent attenuation. Five measurements with repositioning were performed on each sample to determine the reproducibility. Dual energy x-ray absorptiometry (DXA) scans have been performed on the samples for BMD measurements: Three ROIs were selected in the specimens: greater, trochanter intertrochanteric, and femoral neck regions. Coefficient of variations were in the range 1.6% to 2.5%. The determination coefficients (r(2)) between BUA and BMD in site-matched ROIs were 0.81, 0.78, and 0.73, respectively, for the greater trochanteric, intertrochanteric, and femoral neck regions. Our results are consistent with data previously shown at the calcaneus and demonstrate the feasibility of QUS measurements at the femur in vitro, with reasonable reproducibility.

Absorptiometry, Photon↗
PubMed2004

Mapping 245 SSR markers on the Vitis vinifera genome: a tool for grape genetics.

The aim of the present work was to develop a microsatellite marker-based map of the Vitis vinifera genome (n=19), useful for genetic studies in this perennial heterozygous species, as SSR markers are highly transferable co-dominant markers. A total of 346 primer pairs were tested on the two parents (Syrah and Grenache) of a full sib population of 96 individuals (S x G population), successfully amplifying 310 markers. Of these, 88.4% markers were heterozygous for at least one of the two parents. A total of 292 primer pairs were then tested on Riesling, the parent of the RS1 population derived from selfing (96 individuals), successfully amplifying 299 markers among which 207 (62.9%) were heterozygous. Only 6.7% of the markers were homozygous in all three genotypes, stressing the interest of such markers in grape genetics. Four maps were constructed based on the segregation of 245 SSR markers in the two populations. The Syrah map was constructed from the segregations of 177 markers that could be ordered into 19 linkage groups (total length 1,172.2 cM). The Grenache map was constructed with the segregations of 178 markers that could be ordered into 18 linkage groups (total length 1,360.6 cM). The consensus S x G map was constructed with the segregations of 220 markers that were ordered into 19 linkage groups (total length 1,406.1 cM). One hundred and eleven markers were scored on the RS1 population, among them 27 that were not mapped using the S x G map. Out of these 111 markers, 110 allowed to us to construct a map of a total length of 1,191.7 cM. Using these four maps, the genome length of V. vinifera was estimated to be around 2,200 cM. The present work allowed us to map 123 new SSR markers on the V. vinifera genome that had not been ordered in a previous SSR-based map (Riaz et al. 2004), representing an average of 6.5 new markers per linkage group. Any new SSR marker mapped is of great potential usefulness for many applications such as the transfer of well-scattered markers to other maps for QTL detection, the use of markers in specific regions for the fine mapping of genes/QTL, or for the choice of markers for MAS.

Agriculture↗
PubMed2004

One year comparison between two add-back therapies in patients treated with a GnRH agonist for symptomatic endometriosis: a randomized double-blind trial.

BACKGROUND: It has been proposed that hormonal supplementation during prolonged GnRH agonist therapy prevents hypoestrogenic side effects, including bone loss. The optimal combination for long-term treatments with safe metabolic profile remains questionable. A norprogesterone derivative, promegestone, was assessed for the first time in a double-blind trial. METHODS: Seventy-eight patients with endometriosis with rAFS (Revised American Society for Reproductive Medicine) scores of III-IV were randomly assigned to monthly leuprorelin 3.75 mg (1 year) which, after the third injection was used in combination with promegestone 0.5 mg (P) plus either estradiol placebo (PL) or estradiol 2 mg (E) per day. Bone mineral density (BMD) was determined at baseline, 6 and 12 months, and biological and clinical quarterly assessments were performed. Analysis was by the intention to treat method. RESULTS: At month 12, BMD changes from baseline were -6.1 +/- 3.7 and -4.9 +/- 4.0% in the PL-P group, at the spine and hip, respectively. This bone loss was prevented in the E-P group: -1.9 +/- 3.1 and -1.4 +/- 2.3%, respectively (P < 0.0001 inter-group comparisons). The BMD decrease in the E-P group was explained by the changes occurring during the first 6 months of treatment. There was no deleterious change in lipid parameters. Clinical improvement was observed without an inter-group difference. CONCLUSIONS: Estradiol 2 mg and promegestone 0.5 mg per day is an effective and safe add-back therapy, which can be proposed for prolonged leuprorelin treatment over 6 months in severe endometriosis.

Absorptiometry, Photon↗
PubMed2004

Prevalence of vertebral fractures in French women older than 75 years from the EPIDOS study.

The aim of this study was to ascertain the prevalence and severity of vertebral fractures in French elderly women. We used spinal radiographs collected during the baseline examination of the Epidémiologie de l'Ostéoporose (EPIDOS) study, a multicentric prospective study of risk factors for hip fracture. A total of 7598 ambulatory women volunteers were recruited in the EPIDOS cohort using large population-based listings such as voter-registration lists. A subsample of 770 participants were selected for spinal radiographs using a systematic selection procedure. Anteroposterior and lateral radiographs of the thoracic and lumbar spine were reviewed by two trained rheumatologists using the semiquantitative (SQ) method described by Genant et al. [J. Bone Miner Res. 8 (1993) 1137]. Vertebral deformities that could be related to causes other than osteoporosis (i.e., Scheuermann's disease or osteoarthritis) were disregarded. The final analysis was made over 745 women after excluding 25 women whose spine radiographs were incomplete or of poor quality. The sample average age was 80.1 +/- 3.4 years. Vertebral fractures were found in 170 women: 22.8% (95% CI, 19.8-25.8%). A single, two, three, or more vertebral fractures were seen in 99 (58.2%), 43 (25.3%), and 28 (16.5%) of the 170 affected women, respectively. The prevalence of vertebral fractures increased with age from 19.0% (95% CI, 14.9-23.1%) among women 75-79 years old to 21.9% (95% CI, 17.3-26.5%) among those 80-84 years old and to 41.4%(95% CI, 31.0-51.7%) among those 85 years of age and over (Chi-square test for trend P < 0.00016). A significant correlation was found also between the number of vertebral fractures per woman and age (r = 0.108, P = 0.003) and between the spinal fracture index and age (r = 0.105, P = 0.004). We conclude that the prevalence of vertebral fractures is high in French ambulatory elderly women, which confirms the results of previous studies conducted in various Caucasian and Asian populations.

Age Factors↗
PubMed2004

[Nuclear quality of the spermatozoon: exploration tests of the chromatin of human spermatozoa (nuclear proteins)].

During spermiogenesis replacement of histones by protamines results in a highly condensed chromatin. Normal chromatin condensation is important for the function of the spermatozoa to carry the paternal genome. Abnormal chromatin can produce DNA damage such as denaturation or fragmentation and can be associated with impaired spermatogenesis. The degree of chromatin condensation can be studied with aid of different techniques: acidic aniline blue staining, chromomycin A3, acridine orange staining and sperm chromatin structure assay (SCSA), chromatin decondensation tests, gel electrophoresis of basic nuclear proteins em leader These tests provided valuable baseline information about semen or sperm preparation. If chromatin condensation is affected not only in malformed but also in morphologically normal spermatozoa, the proportion of spermatozoa with abnormal chromatin structure, in semen, appears to be potentially useful as predictor of fertilizing ability or pregnancy outcome.

Cell Nucleus↗
PubMed2004

[Postmenopausal osteoporosis: current treatment].

Treatments for post menopausal osteoporosis can reduce by 50 % the risk of fracture, in patients having low bone mineral density, with ou without prevalent fractures. The treatment of calcium and vitamin D insufficiencies is necessary in parallel. Based on anti fracture efficacy of treatments, it is relevant to assess post menopausal women for the risk of osteoporotic fractures, based on clinical risk factors and bone mineral density measurements.

Aged↗
PubMed2004

Microrobots for in vitro fertilization applications.

The Micromanipulation and Micro-actuation Research Group at the LAB has activities related to biological and surgical applications. Concerning cells micromanipulation, our laboratory works in collaboration with the research team "Genetic and Reproduction" of the Besançon's hospital (France). The global final objective is the development of an automatic intra cytoplasmic sperm injection (ICSI) device in order to improve performances and ergonomics of current devices. In the future this new device will contain various modules: module for removal of cumulus cells, modules for characterization of oocytes, microinjection module, cells transport system. The first subsystem developed is a new single cell transport system. It consists in a so-called micropusher which pushes single cells without having contact with the external environment. This micropusher is a ferromagnetic particle (from 400 x 400 x 20 microm3 to 100 x 100 x 5 microm3) which follows the movement of a permanent magnet located under the biological medium. A 2D micro-positioning table moves this magnet under the glass slide. The pusher and cells positions are measured through an optical microscope with a CCD camera located above the biological medium. The second subsystem is developed to measure oocytes mechanical stiffness in order to sort them. We have then developed a micro/nano-force sensor based on the diamagnetic levitation principle: a glass tip end-effector (with 20 microm in diameter) is fixed on the equipment which is in levitation (0.5 mm in diameter, 100 mm in length). When a force is applied to the levitated glass tip, it moves to a new equilibrium position. Thanks to themeasurement of this displacement, the applied force can be measured. Since there is no contact and friction between the levitated tip and the fixed part, the resolution of this sensor is very high (10 nN).

Fertilization in Vitro↗
PubMed2003

[Steroid induced osteoporosis: prevention and treatment].

PURPOSE: Corticosteroid induced osteoporosis (CIO) is the most frequent complication of long-term corticosteroid therapy, and the most frequent cause of secondary osteoporosis. New data from biological, epidemiological and therapeutic studies provide basis for optimal management of this bone disease. MAIN POINTS: Corticosteroids are responsible for both quantitative and qualitative deleterious effects on bone, through their effect on bone cells, mainly on osteoblasts (with both a decrease in osteoblast activity and an increase in apoptosis). Epidemiological studies have shown an increased risk of fractures related to CIO, even for low doses, and during the first 6 months of treatment. Relative risk is 1.3 and 2.6 for peripheral and vertebral fractures respectively. Bone mineral density, measured by dual-energy X-ray absorptiometry, is decreased at spine and hip; the risk of fracture is higher in CIO as compared to post-menopausal osteoporosis, for a similar bone density. Prevention of CIO needs the use of the minimal efficacious dose, and treatment of calcium, vitamin D and gonadal hormones insufficiencies. Patients at risk of fracture, as post-menopausal women with prevalent fractures, should receive a bisphosphonate. PERSPECTIVE: It may be possible to reduce the fracture risk in patients on long-term corticosteroid therapy.

Absorptiometry, Photon↗
PubMed2003

Changes in body composition during post-menopausal hormone therapy: a 2 year prospective study.

BACKGROUND: Post-menopausal hormone therapy (pHT) induces changes in both body composition and bone mineral density (BMD). METHODS: In 109 post-menopausal women beginning either tibolone 2.5 mg (n=29), tibolone 1.25 mg (n=42) or estradiol 2 mg plus norethisterone acetate 1 mg (E2 + NETA) (n=38), we assessed body composition, total and regional BMD by dual energy X-ray absorptiometry, and the serum bone alkaline phosphatase (BAP), osteocalcin and the urinary excretion to type I collagen C-telopeptide (CTX) at baseline and after 2 years. RESULTS: At baseline, BMD at all sites correlated negatively with age and years since menopause, and positively with lean mass and fat mass (r=0.42, P<0.001 and r=0.26, P=0.006 at the total femur). During treatment, BMD increased at all sites (P<0.001), and serum BAP, osteocalcin, and urinary CTX decreased in all groups (P<0.001). Lean mass increased whereas android fat and android obesity index decreased. The increase in BMD at all sites correlated positively with changes of lean mass at 2 years. CONCLUSIONS: Both fat mass and lean mass are related to BMD in post-menopausal women, the relationship being strongest with lean mass; an increase in lean mass and a change in distribution of body fat are observed during treatment with E2 + NETA and tibolone.

Adipose Tissue↗
PubMed2003

Increase in bone mineral density of patients with spondyloarthropathy treated with anti-tumour necrosis factor alpha.

OBJECTIVE: To determine the changes in bone mineral density (BMD) in patients with spondyloarthropathy (SpA) treated with infliximab. PATIENTS AND METHODS: 29 patients (six women; 23 men) aged 22-68 years, with persistently active SpA despite a high dose of non-steroidal anti-inflammatory drug and/or treatment with methotrexate or sulfasalazine, were studied. Median duration of disease was 13 years (range 3-30). Twenty five patients were treated with 5 mg/kg and four with 3 mg/kg of infliximab at weeks 0, 2, 6 and then received either no infusion (n=3), or additional infusion of infliximab every other month (n=6), and the remainder received one infusion only in the case of a relapse. Lumbar and femoral BMD was measured by dual energy x ray absorptiometry at baseline and six months later. Serum osteocalcin and urinary deoxypyridinoline were measured in 19 patients at weeks 0, 2, 24, and in 13 patients at all visits. RESULTS: In six months there was a significant increase in BMD at the spine (3.6%, p=0.001), total hip (2.2%, p=0.0012), and trochanter (2.3%, p=0.0012). A trend for increase (1.1%) was observed at the femoral neck. There was an increase in osteocalcin between baseline and week 6 (third infusion)-median 1.45 micro g/l (p=0.013). No change in marker of bone resorption was observed at the same time. There was no change in biochemical markers between baseline and final visits. There was a trend for a correlation between the decrease at six months in erythrocyte sedimentation rate, and lumbar spine BMD change (r(s)=-0.35, p=0.06). CONCLUSION: These data suggest that a benefit of anti-tumour necrosis factor alpha therapy on BMD in patients with SpA may be through an uncoupling effect on bone cells.

Absorptiometry, Photon↗
PubMed2003

[Therapeutic approaches for omphalocele in developing countries: experience of Central University Hospital of Yopougon, Abidjan, Côte d'Ivoire].

A retrospective study about 80 cases of exomphalos treated in the digestive unit of the paediatric surgery department in Abidjan teaching hospital--Côte d'Ivoire had been performed to analyse the result of this malformation treatment during 8 years. Prenatal diagnosis was made in two cases on six antenatal ultrasounds. Prematurity involved 7% of newborn and their birth weight ranged from 2500 to 4000 grams in 70% of cases. Treatment began in 64% at birth, conservative treatment with merbromine tannage was systematic on the non disrupted exomphalos. Surgery was indicated in the disrupted exomphalos and in the complicated cases of conservative treatment. Intestinal occlusion was the main fatal complication observed in both treatments but most of the time it occurred with surgical closure. Total lethality reached 30%, influenced by exomphalos super infection and by neonatal resuscitation insufficient means. Authors think exomphalos lethality reduction implies antenatal ultrasonographic for early diagnosis which could indicate a possible caesarian section in case of the voluminous exomphalos in order to prevent disruption and neonatal resuscitation operation.

Cote d'Ivoire↗