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.

Experimental study on a large animal model of a new thermoablation technique

BACKGROUND

A novel technique of thermoablation, using a microtube to deliver pulses of hot water vapour, was tested on a large animal model in order to evaluate its efficacy and potential adverse effects.

MATERIALS AND METHODS

The medical device consisted of a microtube extension connected to a hydropneumatic pump. Pulses of pure water were injected though the microtube where they were heated and delivered as vapour into the target zone. The method was tested on the liver of 12 healthy pigs, either during open surgery or percutaneously under ultrasounds.

RESULTS

The technique was efficient and well-tolerated by the animals. Large volumes of necrotic tissue were created in a significantly short time compared to concurrent thermoablative techniques.

CONCLUSION

Anticipating human application, this experimental study demonstrated a safe and efficient innovative thermoablation technique. The first human applications have been successfully performed and will be reported soon.

Reporting of vertebral fractures on spine X-rays

Vertebral fractures are the hallmark of osteoporosis, responsible for increased morbidity and mortality in post-menopausal women. However, two-thirds of vertebral fractures do not come to clinical attention. The aim of this study was to compare the identification of vertebral fractures on spine X-rays among rheumatologists. Study subjects were women aged 60-80 years having potential signs of vertebral fracture and visiting a rheumatologist. X-rays were performed according to standardized procedures. In 629 patients (among 824 included) at least one vertebral fracture was diagnosed, and the X-rays were then sent to a central facility where a semi-quantitative assessment of vertebral fracture was performed by a single rheumatologist trained for this evaluation. According to the vertebral level, kappa scores were between 0.20 to 0.77, i.e., below 0.6 from T4 to T7, and between 0.6 and 0.77 from T8 to L4. The false-negative fractures rate was 25.8% (and 15.7% of them were related to a numbering discrepancy). The rate of false positive fractures was 6.3%. At the patient level 6.8% had actually no fracture. This study shows that 25% of overall vertebral fractures are not diagnosed among patients considered as having at least one fracture. As a consequence, patients who require treatment to reduce fracture risk are not being properly identified.

The severity of vertebral fractures and health-related quality of life in osteoporotic postmenopausal women

Vertebral fractures are the hallmark of osteoporosis, responsible for increased back pain, impairment of mobility and functional limitations. These factors have an impact on patients' health-related quality of life (QOL). The aim of this study was to assess QOL, using QUALEFFO, in osteoporotic postmenopausal women, according to the number and the severity of the vertebral fractures. A group of 629 osteoporotic postmenopausal women (60-80 years) with symptoms that, according to a rheumatologist, could be related to a vertebral fracture, had spine X-rays with standardized procedures. All the X-rays were assessed in a central facility. The number of fractures was a determinant of a low QOL, as indicated by an increased score in physical function (P=0.001), social function (P=0.002) and total score (P=0.027). Patients with higher grades of vertebral deformities, i.e., more severe fractures, had low QOL in these three domains, too (P<0.0001, P<0.0001 and P=0.005, respectively). There was no difference in QOL according to the thoracic or lumbar location of the fractures. Both anterior and middle deformities of the vertebral bodies had a negative impact on QOL. In none of the analyses were the pain and mental function domains of QUALEFFO discriminant among the patients. QOL, assessed by an osteoporosis-specific instrument, is decreased in osteoporotic women as a function of both the number and the severity of the vertebral fractures. Treating women with prevalent fractures may avoid a further decrease in their quality of life.

[Biochemical markers of bone remodeling]

Bone markers are aimed to assess bone cells activity. Some are specific of bone formation (osteocalcin, bone alkaline phosphatase, extension peptides of type I procollagen); others are specific of bone resorption (deoxypyridinoline and peptidebound forms.). Their main applications are: evaluation of fracture risk and follow-up of antiosteoporotic treatments. Their use in clinical practice is difficult: choice of the most appropriate bone marker, relevance of changes, and may require the specialist's opinion.

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.

Raman spectroscopy and the forensic analysis of black/grey and blue cotton fibres

Raman spectroscopy was investigated to determine the optimal conditions, mainly laser wavelength/s, for the analysis of the commonly encountered black/grey and blue cotton fibres dyed with reactive dyes. In this first part, a single blue cotton fibre, its three dye components, and an undyed cotton fibre were analysed with five different laser wavelengths from two different Raman microprobe spectrometers. The quality of the spectra, fibre degradation and speed of acquisition were used to determine that, under the conditions used, the 785 and 830 nm lasers gave superior results. The 632.8 nm laser wavelengths provided good results with little acquisition time and no spectral degradation. Results indicate that, at least, the major dye component could be identified using Raman spectroscopy.

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.

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.

Body weight, body composition, and bone turnover changes in patients with spondyloarthropathy receiving anti-tumour necrosis factor {alpha} treatment

OBJECTIVES

To determine the changes in body weight, body composition, and bone turnover in patients with spondyloarthropathy (SpA) treated with anti-tumour necrosis factor alpha (TNFalpha).

PATIENTS AND METHODS

19 patients with SpA (2 women, 17 men), aged 21-71 years, were studied in a 1 year prospective open study. 17 patients received infliximab: 3 or 5 mg/kg/infusion at weeks 0, 2, 6 and infusions in the case of a relapse (n = 14) or systematically (n = 3); 2 patients received etanercept (25 mg twice a week). Body weight, body composition (lean mass, fat mass), and bone mineral density (BMD; using dual energy x ray absorptiometry) were measured at baseline and at months 6 and 12. Serum insulin-like growth factor-I (IGF-I), bone markers (carboxy terminal telopeptide of collagen Iota (CTX) and procollagen type Iota N terminal propeptide (PINP)) were measured at baseline and months 3, 6, and 12.

RESULTS

In 1 year there was a significant increase in body weight (mean (SD) 2.24 (3.1) kg, p = 0.0004), and in lean mass (1.4 (1.69) kg, p = 0.005), but no changes in fat mass. BMD increased at the spine (5.6%, p = 0.0005) and total femur (2.6%, p = 0.01). CTX decreased from the third month (-50%, p = 0.005) up to 1 year (-30%, p = 0.012), and a trend for an increase in PINP (10%, p = 0.06) and in IGF-I (15%, p = 0.04) was seen at month 3.

CONCLUSION

These data confirm that treatment with anti-TNFalpha in SpA is associated with an increase of BMD, which results from a decrease of bone resorption. Increase in body weight and lean mass is observed in parallel with an increase in IGF-1.

The transfer and persistence of petrol on car carpets

The significance of the presence of petrol in motor vehicle fires has often been challenged due to the possibility of a natural occurrence of petrol residues inside the vehicle. Transfer and persistence studies were undertaken to investigate the potential transfer and persistence of petrol onto vehicle carpets through the 'normal' usage of motor vehicles. The results of the transfer study indicate that petrol may be transferred from the external environment in sufficient quantities via the shoes of drivers or passengers to be detected after a 24 h period, but not after 1 week. Low levels of petrol were detectable after 24 h on all carpet mats where the initial volume was 500 microL or more. The level of evaporation of the petrol detected increased with corresponding increases in the time period between transfer and analysis. The results of the persistence study indicate that small volumes of petrol (less than 100 microL) are unlikely to be detected on carpet after a 24 h period, and volumes of less than 1000 microL are unlikely to be detected on acoustic padding after this time period. Larger volumes may be detected after this period, but will generally not be detectable on either carpet or acoustic padding after 4 weeks. In each case, the petrol that is detected exhibits a chromatographic profile of greater than 60% evaporated petrol. These results demonstrate the significance of finding a large volume of fresh or slightly evaporated petrol on car carpet.

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.

Ostéoporose postménopausique : les traitements actuels

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.

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.

[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.

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.

Partner communication in the arbuscular mycorrhizal interaction

During 400 million years of genome–genome interaction, plants and arbuscular mycorrhizal (AM) fungi have become highly interdependent, both ecologically and physiologically. As a result, the differentiation of a functional mycorrhiza is a multistep process requiring the active participation of both partners. During the presymbiotic stage of the AM interaction, some active molecules present in root exudates rapidly induce several fungal genes, in addition to stimulating important cellular and metabolic functions in the fungus, such as mitochondrial biogenesis and respiration. As a result of this activation, the fungus can use its lipidic reserves and reach further developmental stages. Subsequently, the fungus produces factors that induce new gene expression in roots. The fact that the partners of the AM symbiosis exchange such "pheromonal" active molecules during the presymbiotic stage of their interaction suggests the existence of other cross-signaling molecules during the symbiotic stage. These later signals might be involved in activating fungal fatty acid synthesis and sugar uptake or be responsible for specific plant gene induction. Now the challenge is to characterize the chemical nature and the exact role of these fungal and plant regulators in the AM symbiosis.Key words: arbuscular mycorrhizal symbiosis, signaling, root exudates, Myc factor, respiration, lipid metabolism.

Toxidermie lichénoïde à l’imatinib (Glivec®)

INTRODUCTION

Imatinib (Glivec) is a new therapeutic molecule used for the treatment of chronic myeloid leukemia. Cutaneous side effects with this treatment are common but lichenoid drug eruption is exceptional. We report the first case with profuse cutaneous lichen.

CASE REPORT

A 52 year-old woman presented with a 5-year history of chronic myeloid leukemia. The different chemotherapies had failed (persisting polyadenopathies and splenomegalia). She was treated with imatinib (400 mg/day). Two months after the beginning of this treatment a disseminated cutaneous eruption appeared on the trunk, legs, arms and face without mucosal involvement and composed of dark purple, prurigenous, papules suggestive of lichen planus. The cutaneous biopsy confirmed the diagnosis of lichen planus. Suspension of the drug led to the complete regression of the eruption, without any other local treatment, within 2 months. Reintroduction of the drug led to the recurrence of the lesions.

DISCUSSION

Cutaneous reactions to imatinib are common and occur in 11 to 67 p. 100 of patients depending on the series. More severe cutaneous reactions have been described: exfoliating dermatites, generalized pustulosis, epidermal necrolysis. The aspect of profuse lichenoid eruption of the skin and the correlation with cutaneous lesions clinically and histologically evocative of lichen planus has not been described other than an isolated buccal involvement in a 72 year-old woman. In our patient, study of the imputability criteria is in favor of imatinib's responsibility.