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P Montoya

Publications and source records attributed to P Montoya.

At least 19 recordsLinked to original sources
PubMed2005

[Study of the morphologic variations of the scaphocephaly. Deduction for their systematisation].

PURPOSE: The scaphocephaly is the most frequent craniosynostosis secondary to a premature synostosis of the sagittal suture. Despite this univocal pathogeny there are a great heterogeneity in the skull deformation and their systematisation stay imprecise. The aim of this study was to analyse the different morphology of the scaphocephaly by 3D CT-scan to clarify the different shapes. MATERIAL AND METHODS: This retrospective study was done from the morphometric analysis of forty-two 3D CT-scan (10 girls and 32 boys). The scaphocephaly was classified in two groups according to the systematisation of Stricker and Montaut: the sphenocephaly (large forehead) and the leptocephaly (narrow forehead). The variation of the calvaria shape was analysed and different index were calculated. RESULTS: There were 30 sphenocephaly and 12 leptocephaly. Excepted for the forehead deformation there was a morphometric difference of the occipital pole that was backward rotated in the leptocephaly. In the two groups there were retro-coronal constriction (40.5%) or pre-lambdoid constriction (9.5%) independently of the sagittal synostosis degree. CONCLUSIONS: The morphometric analysis shows that the deformation of the skull secondary to the premature synostosis of the sagittal suture can be different. The adaptative defect of the metopic suture can be to explain this difference. This deformation can be harmonious, or with a retro-coronal constriction resulting in a bitemporal narrowing, or with a pre-lambdoid constriction resulting in an occipital chignon. These results conduce to qualify the surgical correction to adapt at the different shapes.

Child, Preschool↗
PubMed2003

Plagiocephaly: morphometry of skull base asymmetry.

The aim of this study was to perform a morphometric analysis of the skull base to understand the mechanism of asymmetry between malformational and deformational plagiocephaly. Since 1988, we have carried out 102 CT scans with three-dimensional reconstruction of the endocranial side of the skull base. There were 20 cases of malformational plagiocephaly, consisting of 18 unicoronal synostoses (UCS) and two unilambdoid synostoses (ULS), and 82 cases of plagiocephaly without synostosis, made up of 60 cases of frontal plagiocephaly (FP) and 22 of occipital plagiocephaly (OP). The skull base asymmetry was analyzed in three ways: (1) the hemibases and the cranial fossa angles were compared with each other; (2) the structural asymmetry of the chondrocranium was calculated; and (3) the architectural asymmetry was measured in relation to the medio-labyrinthine plane. The skull base asymmetry of malformational plagiocephaly was located in the anterior and middle cranial fossae for UCS and in the posterior and middle cranial fossae for ULS. The asymmetry was the result of a localized structural anomaly of the chondrocranium. The asymmetry of deformational plagiocephaly corresponded to a distortion in relation to the medio-labyrinthine plane while the chondrocranium remained symmetric. The skull base asymmetry of malformational plagiocephaly is secondary to a localized malformation of the chondrocranium, and that of the deformational plagiocephaly is secondary to an architectural deformation.

Analysis of Variance↗
PubMed2003

[The secondary bone grafting in cleft lip and palate: technical notes and indications about 62 cases].

INTRODUCTION: Secondary bone grafting of the maxilla has become a well-accepted procedure in the surgical protocol for rehabilitation of patients with cleft lip and palate (CLP). The aim of this study is to review the surgical procedure and the indication of the secondary bone graft. MATERIALS AND METHODS: Sixty-two secondary bone graft were retrospectively reviewed from 1993 to 2000. There were 50 unilateral CLP and 12 bilateral CLP. The age at the time of bone grafting ranged from 9 years to 25.5 years with a mean at 14.34 +/- 2.9 years. The same operator performed a Gingivoperiosteoplasty (GPO) in all cases and the graft material was cancellous iliac bone in all cases. RESULTS: There were three indications of the bone graft and in each case the objective is different. First the interceptive bone graft in mixed dentition (50%): it was performed prior to the orthodontic treatment 12.8 +/- 2.3 years. The graft provides a bone support for teeth adjacent to the cleft. Second the stabilisation bone graft in permanent dentition (33.8%): it stabilize the orthodontic treatment and/or plan orthognathic surgery (15.2 +/- 1.6 years). Third the consolidation bone graft (16.2%): it was a late secondary bone graft after the complete growth (17,3 +/- 3,6 years) to correct the sequellae. It restored the maxilla continuity, stabilised the clefting teeth and prepared a prosthetic rehabilitation. CONCLUSION: The benefice of the secondary bone graft with GPO are numerous and is a part of the protocol treatment in CLP patients. A multidisciplinary follow up is necessary for the indication and timing of secondary bone grafting. The indication is subject to the clefting teeth, to the occlusal status and to the maxillary growth.

Adolescent↗
PubMed2003

[Clinico-radiological study of the skull deformation in the plagiocephaly without synostosis].

UNLABELLED: The aim of this study was to analyze the mechanism of the skull deformation observed in frontal and occipital plagiocephaly without synostosis. POPULATION AND METHODS: From 1987 to 2001, 96 plagiocephalies without synostosis, 72 males and 24 females, were examined. There were 72 Frontal Plagiocephalies (FP) and 24 Occipital Plagiocephalies (OP). The clinical examination of the neck muscles was performed to find out a torticolis with or without retraction. All patients underwent a 3D CT scan of the skull to exclude a craniostenosis. Cephalic Index (CI) was also calculated. RESULTS: The FP had a torticollis in 89.3% of cases associated with a muscle retraction (54.8%), a tonus asymmetry (16.6%), or in association (28.6%). The skull had a parallelepiped shape and the greater axis was oblique. The CI was 0.85. The OP had a torticollis in 50% of case associated with a retraction (28.6%), a tonus asymmetry (57.1%), or the association (14.3%). The skull had a square shape with an occipital flat and the CI was 0.95. DISCUSSION: The FP and OP are two deformations whose mechanism is different. The FP corresponds to a three plans skull asymmetry secondary to muscle traction on the base of the skull, and the OP corresponds to a posterior localized asymmetry of the skull secondary to compression. CONCLUSION: The traction and/or compression deformation start in utero or in the newborn period and the supine position is an aggravating positional factor.

Anthropometry↗
PubMed2003

Prenatal organization and morphogenesis of the sphenofrontal suture in humans.

OBJECTIVE: The aim of this study was to describe the prenatal structure and morphogenesis of the sphenofrontal suture. METHODS: Eleven human specimens, two embryos and nine fetuses, were prepared for light microscopy study of the sphenofrontal suture. Ten-micrometer sections were made with the microtome in the sagittal plane from the midline to the sphenoidal fontanelle. RESULTS: At the end of the fetal period, the sphenofrontal suture had a five-layer structure like the cranial sutures, and was formed by two different morphogenetic unities. The orbitosphenofrontal suture was formed between the membranous ossification of the orbital part of the frontal bone and the endochondral ossification of the lesser wing of the sphenoid bone, i.e. the ala orbitalis. In the early stage, a transient sphenoethmoidal cartilage was inserted between these two ossifications. The second unit, the lateral sphenofrontal suture, was formed between the frontal bone and the greater wing of the sphenoid, and the ossification was membranous in this portion. It is formed like the cranial suture, directly from the mesenchyme. CONCLUSION: The sphenofrontal suture is a typical fibrous suture arising from two morphogenetic unities.

Body Patterning↗
PubMed2002

[Clinical management of cleft lip and palate in university hospital of Montpellier].

Management of labio-maxillo-palatine clefts has two major requirements: to constitute a multidisciplinary staff (surgical, phonological, orthodontical) intervening as soon as possible and determination of a precise therapeutical chronology not only for primary surgery but also for sequellae. Primary surgical protocol is in cases of total clefts these defined by Malek and Psaume; and for pure labial or incomplete clefts, we perform a neonatal surgery. Integration of interceptive correction of sequellae into thus protocol appears basic: correction of alveolar cleft by gingivoplasty (5 to 7 years) associated with secondary home-graft between 11 to 13 years; early nasal revision since 2 years for functional and aesthetic reasons. Early control of speech development, otologic problems and their management appears a very important point. Introduction of the concept of maxillary distraction appears to us a very important improvement for correcting orthognatic cases with major problems of squeletical growth. Recent introduction of the antenatal diagnosis introduces a new concept in psychological approach of these cases. It is necessary to establish a network for managing these cases since the antenatal period.

Academic Medical Centers↗
PubMed2001

[Imaging of oto-mandibular dysplasias].

The modern imaging opened a possibility of precise exploration of otomandibular dysplasias. The techniques of browsing by IRM and CT Scan and the software of image processing which is associated with these techniques (three-dimensional, superposition and removing of the anatomical structures) allow to carry out a true anatomical dissection of the whole of these malformative syndromes. The study of the skeletal anomalies gains by specifying the disorders of development of the various mandibular segments: temporomandibular joint, ramus and horizontal branch and also, all cranio-maxillar structures: orbital rim, cranial basis. Study of masticatory muscles shows an important damage correlated with skeletal troubles and performs a grading of morphological and functional gravity. This analytical study emphasizes some malformative axis: malar axis in cases of mandibulofacial dystosis, temporomandibular axis in hemifacial microsomia. Modern imaging can appreciate, by development of three-dimensional cephalometry, growth anomalies and quantification of post therapeutical results. At last usefulness of imaging appears in therapeutic modelisation and in the field of Computer-Aided Planning of surgical techniques of osteotomies and overall maxillaries distractions.

Ear↗
PubMed2001

An artificial lung reduces pulmonary impedance and improves right ventricular efficiency in pulmonary hypertension.

OBJECTIVE: Artificial lungs may have a role in supporting patients with end-stage lung disease as a bridge or alternative to lung transplantation. This investigation was performed to determine the effect of an artificial lung, perfused by the right ventricle in parallel with the pulmonary circulation, on indices of right ventricular load in a model of pulmonary hypertension. METHODS: Seven adult male sheep were connected to a low-resistance membrane oxygenator through conduits anastomosed end to side to the pulmonary artery and left atrium. Banding of the distal pulmonary artery generated acute pulmonary hypertension. Data were obtained with and without flow through the device conduits. Outcome measures of right ventricular load included hemodynamic parameters, as well as analysis of impedance, power consumption, wave reflections, cardiac efficiency, and the tension-time index. RESULTS: The model of pulmonary hypertension increased all indices of right ventricular load and decreased ventricular efficiency. Allowing flow through the artificial lung significantly reduced mean pulmonary artery pressure, zero harmonic impedance, right ventricular power consumption, amplitude of reflected waves, and the tension-time index. Cardiac efficiency was significantly increased. CONCLUSIONS: An artificial lung perfused by the right ventricle and applied in parallel with the pulmonary circulation reduces ventricular load and improves cardiac efficiency in the setting of pulmonary hypertension. These data suggest that an artificial lung in this configuration may benefit patients with end-stage lung disease and pulmonary hypertension with right ventricular strain.

Airway Resistance↗
PubMed2001

Field evaluation of a phototoxic dye, phloxine B, against three species of fruit flies (Diptera: Tephritidae).

The xanthene dye phloxine B (D&C Red #28) bait was sprayed against fruit flies in mango orchards in 1996 and 1997. The flies used for testing were Mexican fruit fly, Anastrepha ludens (Loew), West Indian fruit fly, Anastrepha obliqua (Macquart), and Mediterranean fruit fly, Ceratitis capitata (Wiedeman). Results of the experiments indicate that the toxic efficacy of phloxine B against these fruit flies is as good as that of malathion-bait sprays. Results also indicate that type of protein used with phloxine B can dramatically influence its efficacy. Hydrolyzed proteins of corn origin, Mazoferm 802 and Nutriplus, and one from microbial origin, Coltec yeast broth, were best. Phloxine B-bait applications as complete coverage or alternate swaths reduced fly populations as well as 19.5 or 9.8% (AI) malathion-Captor 300. Applications of phloxine B bait at concentrations of 0.12% phloxine B reduced populations as well as those applied at 0.48% (AI). The fruit fly parasitoid Diachasmimorpha longicaudata was adversely affected when exposed to phloxine B-Nutriplus bait but not when exposed to the other proteins.

Animals↗
PubMed2001

[Imaging of cloverleaf skull].

The cloverleaf skull is a rare and due to complex craniosynostosis. This malformation can be isolated or associated with extracranial skeletal anomalies. This anomaly has a poor prognosis both in terms of neurological outcome and esthetic appearance. Our report underscores the need to obtain a global study of the skull, the brain and the cerebral vessels with 3D reconstructions and MRI prior to early surgery.

Craniosynostoses↗
PubMed2000

Strong Amerind/white sex bias and a possible Sephardic contribution among the founders of a population in northwest Colombia.

Historical and genetic evidences suggest that the recently founded population of Antioquia (Colombia) is potentially useful for the genetic mapping of complex traits. This population was established in the 16th-17th centuries through the admixture of Amerinds, Europeans, and Africans and grew in relative isolation until the late 19th century. To examine the origin of the founders of Antioquia, we typed 11 markers on the nonrecombining portion of the Y chromosome and four markers on mtDNA in a sample of individuals with confirmed Antioquian ancestry. The polymorphisms on the Y chromosome (five biallelic markers and six microsatellites) allow an approximation to the origin of founder men, and those on mtDNA identify the four major founder Native American lineages. These data indicate that approximately 94% of the Y chromosomes are European, 5% are African, and 1% are Amerind. Y-chromosome data are consistent with an origin of founders predominantly in southern Spain but also suggest that a fraction came from northern Iberia and that some possibly had a Sephardic origin. In stark contrast with the Y-chromosome, approximately 90% of the mtDNA gene pool of Antioquia is Amerind, with the frequency of the four Amerind founder lineages being closest to Native Americans currently living in the area. These results indicate a highly asymmetric pattern of mating in early Antioquia, involving mostly immigrant men and local native women. The discordance of our data with blood-group estimates of admixture suggests that the number of founder men was larger than that of women.

Africa, Northern↗
PubMed2000

An association study of bipolar mood disorder (type I) with the 5-HTTLPR serotonin transporter polymorphism in a human population isolate from Colombia.

The short variant of a functional length polymorphism in the promoter region of the serotonin transporter has been associated with several behavioural and psychiatric traits, including bipolar mood disorder. The same short allele has also been implicated as a modifier of the bipolar phenotype. Here we evaluate the etiologic/modifier role of this polymorphism in a case (N=103) / control (N=112) sample for bipolar mood disorder (type I) collected from an isolated South American population. We did not detect an association between bipolar disorder and the 5-HTT promoter polymorphism in this sample. However, an excess of the short allele was seen in younger cases and in cases with psychotic symptoms. When combined with data from the literature, the increased frequency of the short allele in patients with psychotic symptoms was statistically significant.

Age of Onset↗
PubMed1999

Activation of cortical and cerebellar motor areas during executed and imagined hand movements: an fMRI study.

Brain activation during executed (EM) and imagined movements (IM) of the right and left hand was studied in 10 healthy right-handed subjects using functional magnetic resonance imagining (fMRI). Low electromyographic (EMG) activity of the musculi flexor digitorum superficialis and high vividness of the imagined movements were trained prior to image acquisition. Regional cerebral activation was measured by fMRI during EM and IM and compared to resting conditions. Anatomically selected regions of interest (ROIs) were marked interactively over the entire brain. In each ROI activated pixels above a t value of 2.45 (p<0.01) were counted and analyzed. In all subjects the supplementary motor area (SMA), the premotor cortex (PMC), and the primary motor cortex (M1) showed significant activation during both EM and IM; the somatosensory cortex (S1) was significantly activated only during EM. Ipsilateral cerebellar activation was decreased during IM compared to EM. In the cerebellum, IM and EM differed in their foci of maximal activation: Highest ipsilateral activation of the cerebellum was observed in the anterior lobe (Larsell lobule H IV) during EM, whereas a lower maximum was found about 2-cm dorsolateral (Larsell lobule H VII) during IM. The prefrontal and parietal regions revealed no significant changes during both conditions. The results of cortical activity support the hypothesis that motor imagery and motor performance possess similar neural substrates. The differential activation in the cerebellum during EM and IM is in accordance with the assumption that the posterior cerebellum is involved in the inhibition of movement execution during imagination.

Adult↗
PubMed1999

[Congenital skull depression. Report of 2 cases].

Congenital depression of the fetal skull is a rare lesion (1 to 2.5 per 10,000 births) resulting in an asymmetrical skull. This depression is caused by exaggerated or prolonged pressure applied to the fetal head in utero or during delivery. Two types of congenital skull depression have been described: deformity without fracture and depression with fracture, the more common form. Congenital skull depression is important because it may be associated with underlying brain injury, especially when the depression is associated with fracture. The simple permanent cosmetic deformity may also constitute a complication. CT scan can now rule out intracranial complications and in this case, a conservative management is reasonable treatment option. The observation period should not exceed six months. After this period, orthopedic or surgical management may be indicated because spontaneous elevation of depression is uncommon after six months. The authors report two cases of congenital skull depression with deformity without fracture. The pathogenesis and treatment are discussed.

Fetal Diseases↗
PubMed1999

[Synovial sarcoma of the mandible in children. Apropos of a case].

UNLABELLED: Synovialosarcoma is an aggressive malignant soft-tissue tumor. It's a mesenchymal tumor rare in the cephalic region in the children. Its occurs most frequently in the extremities, in the adolescents and young adults between 15 and 40 years. His treatment are principally a radical surgical excision. We report the case of a 10 year old boy who had a mandibular tumor developing in the first premolar area and invading the submandibular region. The histologic diagnosis was biphasic synovialosarcoma with epithelial predominance. The staging showed a stage II tumor (5 cm) of the submandibular region with invading the mouth floor and the mandible. After the failure of the polychemotherapy we had performed a radical surgical excision with a functional cervical lymphadenectomy. The tumor was excised in one piece with the horizontal part of the left hemimandible. The treatment was completed by radiotherapy. In a second time a reconstructive surgery was performed with a fibula free flap. The result at one year show a good local control and a perfect esthetic and functional result of the mandible. CONCLUSION: Synovialosarcoma is a very aggressive malignant soft-tissue tumor with a high metastatic risk. Management must be rapid as soon as the diagnosis is made. Surgical excision is the main treatment in association with the chemotherapy and radiotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

The cortical somatotopic map and phantom phenomena in subjects with congenital limb atrophy and traumatic amputees with phantom limb pain.

The extent of the cortical somatotopic map and its relationship to phantom phenomena was tested in five subjects with congenital absence of an upper limb, four traumatic amputees with phantom limb pain and five healthy controls. Cortical maps of the first and fifth digit of the intact hand, the lower lip and the first toe (bilaterally) were obtained using neuroelectric source imaging. The subjects with congenital upper limb atrophy showed symmetric positions of the left and right side of the lower lip and the first toe, whereas the traumatic amputees with pain showed a significant shift (about 2.4 cm) of the cortical representation of the lower lip towards the hand region contralateral to the amputation side but no shift for the toe representation. In healthy controls, no significant hemispheric differences between the cortical representation of the digits, lower lip or first toe were found. Phantom phenomena were absent in the congenital but extensive in the traumatic amputees. These data confirm the assumption that congenital absence of a limb does not lead to cortical reorganization or phantom limbs whereas traumatic amputations that are accompanied by phantom limb pain show shifts of the cortical areas adjacent to the amputation zone towards the representation of the deafferented body part.

Adult↗
PubMed1997

CD4+ T-lymphocyte variations in patients with advanced human immunodeficiency virus infection and counts below 100 cells per microliter.

Variability in CD4+ T-lymphocyte measurements has been described for both normal and human immunodeficiency virus (HIV)-infected persons. Clinical protocols use CD4+ cell counts as surrogate markers for disease progression or response. In this study, we determined the variability of CD4+ T-lymphocytes below 100 cells/microl when measured less than 7 days apart. Two consecutive lymphocyte subset measurements were performed in 55 patients using CD3/CD4 antibodies in a flow cytometer (Epics Profile II). Specimens were collected between 8:00 and 10:00 am within the same week. Data from the first and second measurements were compared. The average total lymphocyte count on the first measurement was 1,064 (360-2,853), and on the second 1,162 (320-2,223; P = 0.07); the percentage CD4 was 1.76 (0-8) on the first, and on the second 1.98 (0-9; P = 0.3); the absolute CD4 cell count on the first measurement was 16.6 (0-57) and on the second 22.8 (0-93; P = 0.01). Statistically significant differences were found between the first and second absolute CD4 T-lymphocytes but not in the CD4 percentage. These differences probably are due to variations in total lymphocyte count. For research protocols, repeating CD4+ cell determinations within a short period is advisable, to ensure a homogeneous population. On the other hand, for day-to-day patient follow-up, a combination of clinical criteria and both percentage and absolute CD4+ cell counts should be used to make treatment decisions, because repeating CD4 cell measurements can be very costly.

Anti-HIV Agents↗