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Biomedical subjects

R Pantoja

Publications and source records attributed to R Pantoja.

10 recordsLinked to original sources
PubMed2001

Bilayer reconstitution of voltage-dependent ion channels using a microfabricated silicon chip.

Painted bilayers containing reconstituted ion channels serve as a well defined model system for electrophysiological investigations of channel structure and function. Horizontally oriented bilayers with easy solution access to both sides were obtained by painting a phospholipid:decane mixture across a cylindrical pore etched into a 200-microm thick silicon wafer. Silanization of the SiO(2) layer produced a hydrophobic surface that promoted the adhesion of the lipid mixture. Standard lithographic techniques and anisotropic deep-reactive ion etching were used to create pores with diameters from 50 to 200 microm. The cylindrical structure of the pore in the partition and the surface treatment resulted in stable bilayers. These were used to reconstitute Maxi K channels in the 100- and 200-microm diameter pores. The electrophysiological characteristics of bilayers suspended in microchips were comparable with that of other bilayer preparations. The horizontal orientation and good voltage clamping properties make the microchip bilayer method an excellent system to study the electrical properties of reconstituted membrane proteins simultaneously with optical probes.

Alkanes↗
PubMed1998

[Central lipoma of the mandible. A new case].

Lipomas are benign neoplasms affecting many organs of the body with adipose tissue. As a bone central lesion they represent less than 1% of all lipomas. In the literature lipomas are reported in different bones: calcaneum, ribs, fibula, phalanges, ulna, frontal and parietal bone. In the jaws 8 cases have been reported, most of them representing radiographic findings the clinician diagnosing cyst or tumor, specially odontogenic tumor. No preference has been reported for any gender, age or race but the condition appears after the fourth decade. We report a case of central lipoma in the mandible with the clinical, radiological and histopathological findings and discuss its origin.

Adipose Tissue↗
PubMed1995

[Anatomic bone and dento-alveolar changes in patients with lip incompetence].

Twenty young patients with clinical labial incompetence have been studied cefalometrically using Delaire's Analysis, in order to determine anatomical alterations who explains this condition. In all of them we have found some anatomical alteration in sagital or vertical plane or both, in maxillary or mandibular squeletal bases or their dento-alveolar squeletic unit. Knowledge of anatomical factors contributing or determining labial incompetence is the key of the planification and execution of an etiologic approach, what is the best way to obtain physiological rapport and consequently good aesthetic results.

Adolescent↗
PubMed1994

[Vertical condylar hyperplasia, clinical and histologic aspects. Apropos of 2 cases].

Condylar hyperplasia is a pathologic condition associated with an overgrowing of the condylar cartilage. It is possible to distinguish two clinical forms; vertical and horizontal when the lesion is unilateral. We have reported two cases of vertical condylar hyperplasia, both of them treated by simple condylectomy, in our opinion the selected treatment. Histopathological images show an increase of the growth and maturation layers of the condylar cartilage and inclusions of cartilaginous tissue, with appearance of glove fingers into the underlying cancellous bone.

Adult↗
PubMed1994

[Changes in the periodontal alveolar bone after surgical restoration of the dental occlusion].

Alveolar cortical bone of 49 including teeth of patients with dento-facial deformities has been studied before and after procedures of orthognathic surgery, performed to give a correct occlusion of those teeth. Standardised radiographic technic was used to measure the width of cortical alveolar lamina. The width was increased in all teeth studied, in a variable degree. This augmentation was explained as morphologic changes to maintain physiologic conditions in teeth's function.

Adolescent↗
PubMed1991

[A new case of adenomatoid odontogenic tumor].

We have reported a new case of adenomatoid odontogenic tumour, treated as is classic, by simple enucleation that is the selected treatment. This lesion is, in fact, a malformation and not a variety of ameloblastoma as some denominations (ameloblastic adenomatoid tumour, adenoameloblastoma) could make to think.

Adolescent↗
PubMed1989

[Cephalometry in maxillofacial surgery].

This paper, makes some references about precisions on base of cephalometric analysis making special emphasis of different tracings that maxillo-facial surgeon must know.

Cephalometry↗