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G Lefort

Publications and source records attributed to G Lefort.

At least 37 records · Page 2Linked to original sources
PubMed1996

The PRINS technique: potential use for rapid preimplantation embryo chromosome screening.

The primed in-situ labelling (PRINS) method is an alternative to in-situ hybridization for chromosomal detection based on the use of chromosome-specific oligonucleotide primers. Using this process, we have developed a simple and semi-automatic method for rapid in-situ detection of human chromosomes. The reaction was performed on a programmable temperature cycler. Specific labelling was obtained in < 2 h reaction. Double PRINS techniques were performed on six morphologically abnormal preimplantation embryos using primers specific for chromosomes 9, 16, 18, 21, X and Y. The majority of these embryos displayed chromosomal abnormalities. The present results demonstrate that PRINS may be a simple and reliable technique applicable in human preimplantation diagnosis.

Blastocyst↗
PubMed1996

FISH and PRINS, a strategy for rapid chromosome screening: application to the assessment of aneuploidy in human sperm.

The co-utilization of FISH and PRINS techniques for in situ chromosome screening was tested on human sperm nuclei. We used a centromeric repeat probe specific for chromosome 4 for FISH. PRINS reactions were performed with alpha-satellite primers specific for either chromosomes 9 or chromosome 18. Double labeling was obtained and estimates of disomy rates were carried out for the three chromosomes.

Adult↗
PubMed1995

Rapid in situ detection of chromosome 21 by PRINS technique.

The "PRimed IN Situ labeling" (PRINS) method is an interesting alternative to in situ hybridization for chromosomal detection. In this procedure, chromosome labeling is performed by in situ annealing of specific oligonucleotide primers, followed by primer elongation by a Taq polymerase in the presence of labeled nucleotides. Using this process, we have developed a simple and semi-automatic method for rapid in situ detection of human chromosome 21. The reaction was performed on a programmable temperature cycler, with a chromosome 21 specific oligonucleotide primer. Different samples of normal and trisomic lymphocytes and amniotic fluid cells were used for testing the method. Specific labeling of chromosome 21 was obtained in both metaphases and interphase nuclei in a 1 hour reaction. The use of oligonucleotide primer for in situ labeling overcomes the need for complex preparations of specific DNA probes. The present results demonstrate that PRINS may be a simple and reliable technique for rapidly detecting aneuploidies.

Base Sequence↗
PubMed1995

PRINS as a method for rapid chromosomal labeling on human spermatozoa.

Direct in situ labeling of human spermatozoa was performed using the PRINS method. This technique is based on annealing of specific oligonucleotide primers, and subsequent primer extension by a Taq DNA polymerase. The reaction was carried out on a programmable temperature cycler, and labeling was obtained in a 1-hr reaction. The method was successfully tested with specific primers for chromosomes 13, 16, and 21. This suggests that PRINS may be a fast and reliable technique for detecting aneuploidies.

Aneuploidy↗
PubMed1995

Use of the primed in situ labelling (PRINS) technique for a rapid detection of chromosomes 13, 16, 18, 21, X and Y.

The primed in situ labelling (PRINS) technique is an alternative to in situ hybridization for chromosomal screening. We have developed a semi-automatic PRINS protocol, using a programmable thermocycler. The method has been successfully tested with specific primers for chromosomes, 13, 16, 18, 21, X and Y. Specific chromosome detection has been obtained on both metaphases and interphase nuclei. This suggests that PRINS may be a reliable technique for detecting aneuploidies and some chromosomal aberrations.

Base Sequence↗
PubMed1995

Amniocentesis before 15 weeks' gestation: technical aspects and obstetric risks.

In a prospective case-control study, early amniocenteses (EAC, n = 242) at between 12 and 14 weeks gestation, were compared with standard amniocenteses (SAC, n = 242) performed at between 15 and 24 weeks gestation. The medical records of these 484 cases were reviewed for indications, success rate, color and volume of amniotic fluid, gestational age, number of needle insertions, location of the placenta, culture failure rate, obstetric complications and therapeutic abortion rate. There were no significant differences between the two groups in success rate, in culture success rate or in the outcome of the pregnancies. The volume of the sample taken was smaller in the EAC patients (P < 0.001), and therapeutic abortions were performed significantly earlier (P < 0.02.) Results show that EAC is feasible from 11 weeks' gestation, and can be performed for the usual indications as an alternative to chorionic villus sampling. In the near future, cytogenetic techniques will enable results to be obtained in less than a week.

Adult↗
PubMed1995

Selection of chromosome-specific primers and their use in simple and double PRINS techniques for rapid in situ identification of human chromosomes.

The PRimed IN Situ labeling (PRINS) technique is an alternative to in situ hybridization for rapid chromosome screening. We have defined and tested new specific oligonucleotide primers for alpha-satellite DNA of several chromosomes. When using a semiautomatic PRINS protocol, specific labeling was obtained in both metaphase cells and interphase nuclei in a 1-h reaction. PRINS may be a simple and reliable technique for rapidly detecting aneuploidies.

Base Sequence↗
PubMed1995

[Direct analysis of the frequency of disomy in human sperm using the PRINS technique].

The PRINS method allows a rapid and specific detection of human chromosomes in situ. We have adapted the PRINS protocol to human sperm. Estimates of disomy have thus been performed for chromosomes 9, 12, 16 and 21 by using alpha-satellite DNA specific primers. The frequencies of disomy ranged from 0.27% to 0.31%. No significant difference was found. These data agree with the hypothesis of an equal distribution of non-disjunctions among chromosomes in male meiosis.

Adult↗
PubMed1995

[Treatment of hip dislocations and subluxations by Petit's splints].

PURPOSE OF THE STUDY: The management of DDH in infants less than one year old is not yet definite. Many ambulant therapeutic methods are described and Pavlik's harness is widely employed. The use of Petit's splints is less well known and we report our experience with 169 cases. MATERIAL AND METHOD: Between 1973 and 1991, Petit's splints were used in 112 cases, following abduction cushions in 55 cases and after Pavlik's harness in 2 cases. 103 hips were dislocated but reducible. This permitted progressive abduction of the hips in order to obtain the reduction of the dislocation and to ensure stabilization by retraction of the slack articular capsule. RESULTS: Only 8 dislocations (4,7 per cent) couldn't be reduced by this procedure and necessitated another treatment. Hips were normal after 5 years of follow up in 118 cases and there were 43 residual dysplasias. 6 post reductional avascular necrosis (3,7 per cent) were recorded as a complication of this method among which only one was a serlous from. DISCUSSION: This ambulatory method for treatment of congenital hip dislocation seems to be forsaken by many authors. Nevertheless its effectiveness has been demonstrated with a complication rate lower than with Pavlik's harness procedure.

Female↗
PubMed1994

[Congenital clubfoot. Analysis of 260 cases followed from birth].

INTRODUCTION: This study is a critical analysis of the results in a homogeneous series of 260 cases of congenital clubfoot followed from birth. MATERIAL AND METHODS: This series of congenital club feet was divided in 2 groups: the stiff forms (144 cases) and the supple forms (116 cases). Daily physical therapy and Denis Brown's splints were begun from the first examination. This method did not allow full correction of deformations in 213 cases. A posterior medial surgical release was performed. Its importance depended on the criteria of radio-clinical analysis before surgery. 46 feet were operated twice. RESULTS: Follow up averaged 7 years. 39 per cent of patients had completed growth, only 18 per cent of feet were not operated. With the surgical treatment, the results were ""very good'' and ""good'' in 75.1 per cent of cases, according to an analysis using Seringe's criteria. 21 per cent were operated again, on an average between 3 and 8 years, with poorer results than at first surgery. DISCUSSION: The quality of the results depends on the quality of the functional treatment. Poor control of equinism with Denis-Brown splints can be corrected by using Seringe's articulated splints or by a series of plaster casts. CONCLUSION: Many technical factors influence the results. The quality of post-operative contention is stressed.

Child, Preschool↗
PubMed1994

[Rapid in situ detection of chromosome 21 by the PRINS technique].

The PRINS technique has been used to rapidly detect chromosomes 21 in both metaphases and interphase nuclei. A specific labeling was obtained in preparations from lymphocytes and amniotic fluid cells. The method is based on annealing of specific oligonucleotide primers and subsequent primer extension by a Taq DNA polymerase. PRINS is an interesting alternative to in situ hybridization for cytogenetic diagnosis and physical mapping.

Amniocentesis↗
PubMed1993

Multifetal pregnancy reduction: a consecutive series of 61 cases.

OBJECTIVE: The effect of selective fetocide on the course of 61 multiple pregnancies. DESIGN: An observational study. SETTING: A tertiary centre. SUBJECTS: 61 women whose pregnancies included 37 triplets, 18 quadruplets, 5 quintuplets and 1 hepatuplet; 97% followed IVF or the induction of ovulation. The aim of the procedure in most cases was to obtain twins. INTERVENTIONS: Selective reduction was performed before 13 weeks gestation under general anaesthesia, using either a transcervical (n = 26) or transabdominal approach (n = 35). Fifty-four twins, 4 singletons and 3 triplets were obtained after the procedure. MAIN OUTCOME MEASURE: Preterm labour rate. RESULTS: The rate of unplanned fetal loss was 13% and was related to the number of suppressed embryos (P < 0.05). The preterm labour rate was 56.6%, the mean gestation at delivery was 35.6 weeks. Seven deliveries were before 32 weeks and led to all neonatal deaths. A comparison with published data suggested that fetal reduction reduced the rate of preterm labour in high multiple pregnancies; in 24 twin pregnancies obtained after reduction of triplets there was probably a gain of 2 weeks gestation. Severe growth retardation occurred in 13%. The perinatal mortality rate was 10.8%. CONCLUSIONS: Selective termination reduces but does not prevent early preterm labour. The procedure is of value in pregnancies with more than 3 fetuses and should be considered carefully for triplet pregnancies.

Abortion, Induced↗
PubMed1993

Late vaginal induced abortion after a previous cesarean birth: potential for uterine rupture.

This descriptive study was conducted to evaluate the risk of uterine rupture in cases of late vaginal induced abortions among women with previous cesarean sections. 23 women were referred at a mean gestational age of 23.9 (SD 6.9) weeks of gestation after one or two cesarean sections. Indications for terminating the pregnancy were maternal diseases in 4 cases and fetal anomalies in 19 cases. RU 486 and/or prostaglandins were used for cervical ripening and to induce labor. Vaginal birth was obtained in 20 cases (86.9%) with an average duration of 72 (SD 52) h. Cesarean section was performed in the remaining 3 women because no cervical dilation could be obtained. One uterine rupture occurred and was treated with conservation of the uterus. Late termination of pregnancy in such cases can be achieved without cesarean section with a high success rate.

Abortifacient Agents, Nonsteroidal↗
PubMed1993

Familial cystic hygroma. Report of 8 cases in 3 families.

The authors report 8 cases of familial cystic hygroma concerning 3 families. In the first family, the two affected fetuses with normal karyotypes showed cystic hygroma of the neck associated with campomelic long bone disease. No other fetal anomalies in the two fetuses were found in the second family, and only one of the four abortuses revealed associated malformations (meningomyelocoele, cleft palate) in the third family. In all these cases, parental consanguinity is found, supporting an autosomal recessive mode of inheritance.

Abnormalities, Multiple↗
PubMed1993

Multiple congenital anomalies associated with an oto-palato-digital syndrome type II.

We report the case of a male fetus with an oto-palato-digital (OPD) type II syndrome and multiple congenital anomalies (MCA) including omphalocoele, hypospadias, thoracic dysplasia, skeletal abnormalities, pulmonary hypoplasia and an absent right adrenal gland. These MCA are sometimes reported in Melnick-Needles syndrome, which leads us to discuss the possibility that the spectrum of malformations in these two syndromes might be due to two allelic forms of the same X-linked gene.

Abnormalities, Multiple↗
PubMed1993

X-linked alpha-thalassemia/mental retardation syndrome. Linkage analysis in a new family further supports localization in proximal Xq.

Linkage analysis was performed in a three generation family with three males affected by the recently delineated X-linked form of alpha-thalassemia/mental retardation syndrome (ATR-X). Results are in agreement with the linkage study reported by Gibbons et al in 1992 and further confirm that the ATR-X gene is located in proximal Xq. Positive LOD scores were obtained for several markers situated in the pericentromeric region. A maximum LOD score of 2.09 at a recombination fraction of 0 was obtained for DXS453 located at the boundary q12-q13.1. The nearest flanking loci demonstrating recombination with the disease locus were AR at Xq11.2-q12 on the centromeric side and DXS72 at Xq21.1 on the telomeric side. Consequently the authors were able to reduce the previously defined candidate region for the gene location. Their results are compatible with a distal boundary at Xq21.1 instead of q21.31.

Chromosome Mapping↗