PubMed Health⌕ Search

Biomedical subjects

M P Vazquez

Publications and source records attributed to M P Vazquez.

At least 19 recordsLinked to original sources
PubMed2001

[The Wiedemann-Beckwith syndrome and a congenital cataract].

Wiedemann-Beckwith syndrome is a congenital syndrome with characteristic abnormalities: omphalocele, macroglossia, neonatal gigantism, visceromegaly, hemihypertrophy and a predisposition to embryonic tumors. Ophthalmologic abnormalities have not been described with Wiedemann-Beckwith syndrome. The authors report one case of Wiedemann-Beckwith syndrome associated with bilateral congenital cataract. Family studies indicate linkage of the Wiedemann-Beckwith syndrome locus to the marker 11p15,5. The genetics of cataract is heterogenic. Several mutations responsible for congenital cataract have been described. The association of the Wiedemann-Beckwith syndrome and cataract may contribute to the understanding of the genetics of congenital cataract.

Beckwith-Wiedemann Syndrome↗
PubMed2000

Neurophysiological brainstem investigations in isolated Pierre Robin sequence.

Polysomnography, electromyography (EMG) of the face, tongue, and soft palate, blink reflexes (BRs), EMG during bottle-feeding, and brainstem auditory evoked responses (BAERs) were performed in 25 newborn babies with isolated Pierre Robin sequence (PRS) to aid in evaluation and management. Obstructive apneas were found in 23/24 patients (the 25th having undergone tracheotomy). Number and duration of central respiratory pauses were always normal, as well as electroencephalographic and clinical organization of sleep stages. EMG recruitment pattern in facial and lingual muscles, and BRs were normal in all cases. EMG recruitment pattern in muscles of the soft palate was normal in 14/25 patients, showed a reduced average amplitude with short-duration and low amplitude motor unit potentials in 10/25, and showed signs of denervation in 1/25. EMG during bottle-feeding showed sucking-swallowing disorders in 20/25 patients. BAERs showed a bilateral conductive impairment with increased latencies and thresholds in 5/19 patients, but with normal and symmetric I-III and I-V interpeak latencies in 19/19. These neurophysiological findings suggest that in isolated PRS a dysfunction of the lingual and pharyngeal motor organization exists without any structural impairment in brainstem nuclei and pathways.

Blinking↗
PubMed2000

Assessment of p57(KIP2) gene mutation in Beckwith-Wiedemann syndrome.

Beckwith-Wiedemann syndrome (BWS) is an overgrowth disorder involving developmental anomalies, tissue and organ hyperplasia and an increased risk of embryonic tumours (most commonly Wilms' tumour). This multigenic disorder is caused by dysregulation of the expression of imprinted genes in the 11p15 chromosomal region. It may involve paternal uniparental disomy (UPD), loss of imprinting of the IGF2 gene, maternal inherited translocations and trisomy with paternal duplication. Recently, a small proportion of BWS patients has been shown to have a mutation in the paternal imprinted p57(KIP2) gene, which encodes a cyclin-dependent kinase inhibitor and negatively regulates cell proliferation. We screened for p57(KIP2) gene mutations in 21 BWS patients with no 11p15 UPD in leucocyte DNA. All patients had a phenotype typical of BWS. We analysed the entire coding sequence of p57(KIP2), including intron-exon boundaries, by direct sequencing of five PCR-amplified fragments. No mutation was found in the p57(KIP2) gene. Our results are consistent with those of previous studies showing that mutation of p57(KIP2) is infrequent in BWS. Thus, other mechanisms of p57(KIP2) silencing (imprinting errors) and/or other 11p15 genes are probably involved in the pathogenesis of BWS.

Beckwith-Wiedemann Syndrome↗
PubMed1999

Functional analysis of the intergenic regions of TcP2beta gene loci allowed the construction of an improved Trypanosoma cruzi expression vector.

TcP2beta ribosomal protein genes in Trypanosoma cruzi are encoded by four different loci, H6.4, H1.8, H1.5 and H1.3. All loci have a similar organization, except for H1.8 that harbors two TcP2beta genes arranged in tandem and separated by a short repetitive sequence, named SIRE (short interspersed repetitive element), which is also found upstream of the first gene of the tandem and downstream of the second. In this locus the trans-splicing signal of TcP2beta is located within the SIRE element, while in the other loci it is positioned within the first 50bases upstream of the AUG with an AG acceptor site at position -12 respective to the initiation codon. Transient transfection experiments were used to evaluate the efficiency of these two different trans-splicing regions to drive CAT activity. The region named HX1 located upstream the TcP2beta H1. 8 gene was clearly more efficient than the SIRE sequence contained in the region named HX2. Therefore, we decided to use the HX1 region to ameliorate the performance of the cryptic trans-splicing signal present in the T. cruzi expression vector pRIBOTEX (Martinez-Calvillo, S., López, I., Hernandez, H., 1997. pRIBOTEX expression vector: a pTEX derivative for a rapid selection of Trypanosoma cruzi transfectants. Gene 199, 71-76). By insertion of the region HX1 downstream of the ribosomal promoter of pRIBOTEX, we constructed pRHX1CAT40 that, in stable transfected cells, was able to drive CAT activity 2760 times more efficiently than the control plasmids. Based on this, a novel plasmid vector was conceived, named pTREX-n, which retains the neo gene of pRIBOTEX as a positive selectable marker and replaces the CAT-SV40 cassette in pRHX1CAT40 by a multiple cloning site.

Animals↗
PubMed1999

Linkage analysis of 5 novel van der Woude syndrome kindreds to 1q32-q41 markers further supports locus homogeneity of the disease trait.

van der Woude syndrome (vWS, MIM 119300) is a rare autosomal dominant clefting condition with cardinal features of mucous cysts (lower-lip pits) and clefts to the lip and/or palate. The vWS gene has been assigned to a locus in 1q32-q41 by linkage analysis and physical mapping. We have investigated 5 novel vWS families through probands attended for cleft lip and/or palate repair at the Department of Maxillofacial Surgery of Hôpital Trousseau, Paris, in order to tentatively refine the genetic map of the vWS region in 1q32-q41 and possibly identify unlinked pedigrees. Linkage analysis was carried out to 6 microsatellite markers (D1S249, D1S425, D1S491, D1S205, D1S414, D1S425), yielding a maximum cumulative LOD score of Z = 3.27 at theta = 0.00 for D1S245. The innermost four markers were found to be tightly linked to one another, with no evidence for recombination. Our results support linkage of vWS within a region of tightly linked markers and do not favour locus heterogeneity of the disease trait.

Chromosome Mapping↗
PubMed1999

[Circumscribed mandibular osteitis in children due to hematogenous dissemination. Apropos of 5 clinical cases].

In children, mandibular swelling associated with an X-ray bone osteolysis may correspond to tumoral or infection diseases. Circumscribed osteitis of a child's mandibula, with no dental etiology occurs around 7-years of age, adjacent to a healthy first molar. Five cases reports were analyzed. Clinically, it is a bone swelling of the mandibula's lateral cortical associated with a soft tissue swelling. X-ray signs were not specific but all cases showed a bone lacuna with sharp outlines. Such clinical and X-ray signs strongly suggest diagnosis of osteitis which has a higher incidence than malignant tumors. The lack of dental pathology suggests bloodstream dissemination from another localized sepsis. Surgical removal of pathologic bone in addition to antibiotics (6 or 8 weeks) appears to be an effective treatment.

Amoxicillin↗
PubMed1999

Intraoral mandibular distraction: indications, technique and long-term results.

This report describes the experience of the Trousseau Hospital, Paris, France, with distraction osteogenesis of the mandible using an intraoral distraction device. From 1993 to 1998, 26 paediatric patients with mandibular hypoplasia underwent distraction of the mandible using the Leibinger Intraoral Distractor. The majority of the patients had hemifacial microsomia. Distraction was performed at a rate of 1 mm a day following complete osteotomy of the mandible. A mean of 15 mm of distraction was obtained. In conjunction with combined orthodontic management, satisfactory morphologic results were achieved in the majority of patients with good facial symmetry, adequate occlusal relationships and balanced maxillary mandibular relationships. Radiographic evaluation revealed that substantial new bone formation and remodelling was induced by the intraoral distraction along the entire hemimandible on the distracted side and that this contributed significantly to the aesthetically pleasing clinical results.

Adolescent↗
PubMed1998

Arteriovenous malformations of the dental arcades. The place of endovascular therapy: results in 12 cases are presented.

Twelve arteriovenous malformations of the dental arcades (AVMDAs) (seven mandibular and five maxillary) were seen in our institution between 1977 and 1997. All these lesions consisted of true arteriovenous shunts (of either nidus or fistulous type) involving the bone, with or without soft tissue extension. Haemorrhage was present in eight patients (67%); either torrential, necessitating emergency embolization, or recurrent and progressive. Teeth instability was detected in all patients and was the origin of the bleeding. All lesions were embolized. Lesions in nine patients were embolized with Polyvinyl Alcohol Particles (PVA): this helped to stabilize the situation but could not avoid recurrences in all patients, necessitating complementary embolizations and or surgery. The use of acrylic glue (N-Butyl-Cyano-Acrylate [NBCA] Histoacryl) as the embolic agent has changed the results obtained tremendously. Eight patients have been treated with NBCA (five as complementary therapy to PVA during later sessions and three at the first attempt); injection either via the transarterial route or direct transcutaneous puncture (four patients) achieved a cure in four of these lesions (34%) with stability at long-term follow-up of all the other AVMs. Embolization with glue represents the therapy of choice in these sometimes life-threatening lesions, achieving a cure if directed towards the osseous venous lakes. Surgery, often leading to facial mutilation and necessitating massive reconstruction should be avoided nowadays, at least as the initial therapy.

Adolescent↗
PubMed1997

The Beckwith-Wiedemann syndrome phenotype and the risk of cancer.

Beckwith-Wiedemann syndrome (BWS) comprises of a number of childhood abnormalities, often associated with one or more tumors. Thirty-eight patients were investigated to determine clinical and/or biological signs associated with a tumor presence. Our patients exhibited a higher incidence of tumor development (21%) than that previously reported, underlying the care with which such patients should be followed, when particular clinical features are observed: visceromegaly affecting three organs (liver, kidney, spleen), and also family history with sign of BWS such as macroglossia, omphalocele, hemihypertrophy, embryonic tumor), high body weight at birth (> or = +2 standard deviations and diastasis recti.

Beckwith-Wiedemann Syndrome↗
PubMed1997

Submerged intraoral device for mandibular lengthening.

The authors report a new technique for mandibular distraction. Lengthening of the mandible by gradual intraoral distraction was obtained in nine young patients. An intraoral device was used in order to avoid external scars. Seven patients had hemifacial microsomia, one patient had a ramus hypoplasia after TMJ ankylosis and one patient had the Treacher-Collins syndrome. The amount of mandibular lengthening ranged from 12 to 28 mm depending on the duration of expansion. Retention after expansion, to allow ossification to take place, lasted for 3 weeks on average. The follow-up period ranged from a minimum of 5 months to a maximum of 44 months.

Ankylosis↗
PubMed1997

[Mandibular distraction].

The authors review the bone lengthening techniques used in orthopaedics, analyse the application of osteogenesis by surgical distraction of the mandible and describe the progress in techniques and equipment. The presentation of clinical cases of mandibular hypoplasia treated by intraoral distraction emphasizes the value of this new technique, particularly in terms of the morphological results, which are superior to those obtained by conventional techniques.

Child↗
PubMed1995

Cloning and sequence analysis of the TcP2 beta cDNA variants of Trypanosoma cruzi.

P2 beta acidic ribosomal protein is a relevant antigen in Chagas' disease. cDNA cloning demonstrated that Trypanosoma cruzi expresses at least six types of TcP2 beta transcripts that differed by point nucleotides substitutions. The distribution and type of mutations seemed to follow the typical structural organization of eukaryotic acidic ribosomal proteins. Most of the synonymous changes clustered in the amino-terminus, suggesting that conservation of this domain was crucial for an equivalent functional ability of each TcP2 beta variant to bind to the ribosome. Interestingly, most amino acid changes in the central-globular and hinge domains caused polymorphism in putative phosphorylatable sites.

Amino Acid Sequence↗
PubMed1994

A short interspersed repetitive element provides a new 3' acceptor site for trans-splicing in certain ribosomal P2 beta protein genes of Trypanosoma cruzi.

Four Trypanosoma cruzi genomic DNA fragments carrying different TcP2 beta genes have been isolated and sequenced. Three of them had a single TcP2 beta gene, while the 3.8-kb-long DNA segment encoding the TcP2 beta-H1.8 locus showed two TcP2 beta genes arranged in tandem. These genes were physically connected by a 428-bp-long DNA sequence that was also located immediately 5' to the first gene and immediately 3' to the second. Comparison of the 4 TcP2 beta gene loci, suggested that the insertion of this repeated element originated the duplication of its target sequence, a poly(dT) stretch. Approximately 1200 copies of this short sequence, named short interspersed repetitive element (SIRE), were found scattered in the genome. Analysis of the 5' non-coding regions of different TcP2 beta mRNAs, and RNA-PCR experiments suggested that the insertion of a SIRE upstream of a TcP2 beta-H1.8 gene introduced a new 3' spliced leader (SL) acceptor site in the TcP2 beta-H1.8 pre-mRNAs, encoded within the SIRE. Consequently, in the mature H1.8 mRNA the SL sequence is followed by 38 bases directly transcribed from the SIRE. Structural and functional features of this repeated element reveal similarity to the short interspersed repetitive DNA sequences detected in the genomes of several microorganisms.

Animals↗
PubMed1994

Amputation of penis after circumcision--penoplasty using expandable prosthesis.

A two-year-old boy was referred for correction of an amputation of penis following ritual circumcision. The reconstruction involved mobilization of the profound part of corpora cavernosa and coverage by a vascularised flap taken from the hypogastric area through the use of a sub-cutaneous expandable prosthesis. After two years, appearance of the neo-penis is satisfactory considering the initial lesions.

Amputation, Traumatic↗
PubMed1994

[Bone distraction using an external fixator: a new mandibular lengthening technic. A preliminary study apropos of 2 cases of children with mandibular hypoplasia].

The authors expose a technical innovation concerning mandibular lengthening without any bone graft, by applying to the mandibular Ilizarov's principles about limb lengthening by osseous distraction. This surgical technique concerns children with mandibular hypoplasia, like the Hanhart's syndrome (aglossia-adactylia, first observation), or Hemifacial Microsomia (second observation). The purpose of this new technique is mandibular lengthening with functional and aesthetic correction of the mandibular growth deficiency, and minimal morbidity. A specialist staff is essential to realize a distraction device with his minimal and appropriate shape for children, as well as a protection device conception. This external distraction device is placed with transmandibular pins. After mandibular corticotomy by endobuccal incision, the distraction is accomplished, at home by the parents, at the rythm of 1 mm p. two days. The distraction goes on about 2 months, depending on the lack of mandibular growth, and a retention device, much more light, is necessary during 8 weeks more to stabilize the osteogenesis. At the term of an eight weeks gradual distraction, the mandibular lengthening is 17.5 mm for the horizontal ramus (first observation), and 13 mm for the vertical ramus (second observation). The functional and aesthetic results, the swift and secure surgical procedure, lead to put forward this mandibular distraction technique in any mandibular or facial defects.

Abnormalities, Multiple↗