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1.
Mol Genet Metab ; 114(3): 451-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25555642

RESUMEN

Genetic sequencing has become a critical part of the diagnosis of certain forms of pancreatic beta cell dysfunction. Despite great advances in the speed and cost of DNA sequencing, determining the pathogenicity of variants remains a challenge, and requires sharing of sequence and phenotypic data between laboratories. We reviewed all diabetes and hyperinsulinism-associated molecular testing done at the Seattle Children's Molecular Genetics Laboratory from 2009 to 2013. 331 probands were referred to us for molecular genetic sequencing for Neonatal Diabetes (NDM), Maturity-Onset Diabetes of the Young (MODY), or Congenital Hyperinsulinism (CHI) during this period. Reportable variants were identified in 115 (35%) patients with 91 variants in one of 6 genes: HNF1A, GCK, HNF4A, ABCC8, KCNJ11, or INS. In addition to identifying 23 novel variants, we identified unusual mechanisms of inheritance, including mosaic and digenic MODY presentations. Re-analysis of all reported variants using more recently available databases led to a change in variant interpretation from the original report in 30% of cases. These results represent a resource for molecular testing of monogenic forms of diabetes and hyperinsulinism, providing a mutation spectrum for these disorders in a large North American cohort. In addition, they highlight the importance of periodic review of molecular testing results.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus/diagnóstico , Pruebas Genéticas , Hiperinsulinismo/congénito , Células Secretoras de Insulina/metabolismo , Niño , Diabetes Mellitus/genética , Diabetes Mellitus Tipo 2/genética , Femenino , Humanos , Hiperinsulinismo/diagnóstico , Hiperinsulinismo/genética , Recién Nacido , Masculino , Mosaicismo , Mutación , Fenotipo , Análisis de Secuencia de ADN , Factores de Tiempo
2.
Eur Arch Otorhinolaryngol ; 272(9): 2371-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25359192

RESUMEN

We hypothesize that three-dimensional imaging using cone beam computed tomography (CBCT) is suitable for calculating nasoseptal flap (NSF) dimensions. To evaluate our hypothesis, we compared CBCT NSF dimensions with anatomical dissections. The NSF reach and vascularity were studied. In an anatomical study (n = 10), CBCT NSF length and surface were calculated and compared with anatomical dissections. The NSF position was evaluated by placing the NSF from the anterior sphenoid sinus wall and from the sella along the skull base towards the frontal sinus. To visualize the NSF vascularity in CBCT, the external carotic arteries were perfused with colored Iomeron. Correlations between CBCT NSFs and anatomical dissections were strongly positive (r > 0.70). The CBCT NSF surface was 19.8 cm(2) [16.6-22.3] and the left and right CBCT NSF lengths were 78.3 mm [73.2-89.5] and 77.7 mm [72.2-88.4] respectively. Covering of the anterior skull base was possible by positioning the NSF anterior to the sphenoid sinus. If the NSF was positioned from the sella along the skull base towards the frontal sinus, the NSF reached partially into the anterior ethmoidal sinuses. CBCT is a valuable technique for calculating NSF dimensions. CBCT to demonstrate septum vascularity in cadavers proved to be less suitable. The NSF reach for covering the anterior skull base depends on positioning. This study encourages preoperative planning of a customized NSF, in an attempt to spare septal mucosa. In the concept of minimal invasive surgery, accompanied by providing customized care, this can benefit the patients' postoperative complaints.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional , Tabique Nasal/diagnóstico por imagen , Base del Cráneo/diagnóstico por imagen , Colgajos Quirúrgicos , Anciano , Anciano de 80 o más Años , Cadáver , Disección , Femenino , Seno Frontal/diagnóstico por imagen , Humanos , Masculino , Tabique Nasal/cirugía , Base del Cráneo/cirugía , Seno Esfenoidal/diagnóstico por imagen
3.
Clin Oral Investig ; 17(8): 1919-27, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23371754

RESUMEN

To compare the accuracy of linear and angular measurements between cephalometric and anatomic landmarks on surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols was the aim of this study. CBCT scans were made of cadaver heads and 3D surface models were created of the mandible using two different segmentation protocols. A high-resolution laser surface scanner was used to make a 3D model of the macerated mandibles. Twenty linear measurements at 15 anatomic and cephalometric landmarks between the laser surface scan and the 3D models generated from the two segmentation protocols (commercial segmentation (CS) and doctor's segmentation (DS) groups) were measured. The interobserver agreement for all the measurements of the all three techniques was excellent (intraclass correlation coefficient 0.97-1.00). The results are for both groups very accurate, but only for the measurements on the condyle and lingual part of the mandible, the measurements in the CS group is slightly more accurate than the DS group. 3D surface models produced by CBCT are very accurate but slightly inferior to reality when threshold-based methods are used. Differences in the segmentation process resulted in significant clinical differences between the measurements. Care has to be taken when drawing conclusions from measurements and comparisons made from different segmentations, especially at the condylar region and the lingual side of the mandible.


Asunto(s)
Tomografía Computarizada de Haz Cónico/instrumentación , Modelos Anatómicos , Cadáver , Humanos , Propiedades de Superficie
4.
Clin Anat ; 26(4): 430-5, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22431331

RESUMEN

What can be learned from historical anatomical drawings and how to incorporate these drawings into anatomical teaching? The drawing "A skull sectioned" (RL 19058v) by Leonardo da Vinci (1452-1519), hides more detailed information than reported earlier. A well-chosen section cut explores sectioned paranasal sinuses and ductus nasolacrimalis. A dissected lateral wall of the maxilla is also present. Furthermore, at the level of the foramen mentale, the drawing displays compact and spongious bony components, together with a cross-section through the foramen mentale and its connection with the canalis mandibulae. Leonardo was the first to describe a correct dental formula (6424) and made efforts to place this formula above the related dental elements. However, taking into account, the morphological features of the individual elements of the maxilla, it can be suggested that Leonardo sketched a "peculiar dental element" on the position of the right maxillary premolar in the dental sketch. The fact that the author did not make any comment on that special element is remarkable. Leonardo could have had sufficient knowledge of the precise morphology of maxillary and mandibular premolars, since the author depicted these elements in the dissected skull. The fact that the author also had access to premolars in situ corroborates our suggestion that "something went wrong" in this part of the drawing. The present study shows that historical anatomical drawings are very useful for interactive learning of detailed anatomy for students in medicine and dentistry.


Asunto(s)
Anatomía/historia , Cráneo/anatomía & histología , Diente/anatomía & histología , Historia del Siglo XV , Historia del Siglo XVI , Italia
5.
Clin Anat ; 25(2): 168-75, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21748808

RESUMEN

Anatomical professionals know better than anyone else that donated bodies are a valuable asset to anatomical science and medical education. They highly value voluntary donations, since a dearth of bodies negatively affects their profession. With this in mind, we conducted a survey (n = 54) at the 171st scientific meeting of the Dutch Anatomical Society in 2009 to see to what extent anatomical professionals are willing to donate their own body. The results reveal that none of the survey participants are registered as a whole body donor and that only a quarter of them would consider the possibility of body donation. We argue that the two main constraints preventing Dutch anatomical professionals from donating their own body are their professional and their social environments. In contrast to the absence of registered body donors, half of the anatomical professionals are registered as an organ donor. This figure far exceeds the proportion of registered organ donors among the general Dutch population.


Asunto(s)
Anatomía , Donación Directa de Tejido , Disección/psicología , Conocimientos, Actitudes y Práctica en Salud , Médicos/psicología , Distribución por Edad , Recolección de Datos , Femenino , Humanos , Masculino , Países Bajos , Distribución por Sexo , Obtención de Tejidos y Órganos
6.
Cleft Palate Craniofac J ; 48(5): 623-30, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20849272

RESUMEN

OBJECTIVE: The purpose of this study was to determine the accuracy and repeatability of linear anthropometric measurements on the soft tissue surface model generated from cone beam computed tomography scans. MATERIALS AND METHODS: The study sample consisted of seven cadaver heads. The accuracy and repeatability were assessed by means of a series of 21 standardized, linear facial measurements derived from 11 landmarks taken both directly on the face with a set of digital calipers and indirectly from a three-dimensional soft tissue surface model generated from a cone beam computed tomography scan of the heads using SimPlant® Ortho Pro software. The landmarks and measurements were chosen to cover various regions of the face with an emphasis on the oral-nasal region. The cone beam computed tomography measurements were compared with the physical measurements. Statistical analysis for the repeatability was done by means of the intraclass coefficient. Accuracy was determined by means of the absolute error and absolute percentage error. RESULTS: The cone beam computed tomography measurements were very accurate when compared with the physical measurements (0.962 to 0.999). Except for one measurement, between point tragion (t) and nasion (n) (mean, 1.52 mm), all the measurements had a mean absolute error of less than 1.5 mm. CONCLUSIONS: The three-dimensional surface models derived from cone beam computed tomography images are sufficiently precise and accurate for the anthropometric measurements.


Asunto(s)
Antropometría/instrumentación , Tomografía Computarizada de Haz Cónico/métodos , Cara/anatomía & histología , Cara/diagnóstico por imagen , Imagenología Tridimensional , Cadáver , Humanos , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Programas Informáticos
7.
Eur J Pediatr ; 169(12): 1495-501, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20640442

RESUMEN

Evidence shows that psychosocial problems among children and adolescents with asthma interfere with adherence to treatment and therefore need attention in asthma care. It is unknown whether the already frequently implemented asthma-related quality of life (QoL) instruments reflect psychosocial problems in children with asthma. The aim of this study was to assess the relationship between asthma-related QoL and psychosocial problems and to determine whether an asthma-related QoL instrument is able to identify those children and adolescents with asthma with major psychosocial problems. In a multicenter study psychosocial problems (Strengths and Difficulties Questionnaire) and asthma-related QoL (Pediatric Asthma (Caregivers) Quality of Life Questionnaire) were obtained in children and adolescents with asthma aged 6-16 years and their caregivers. A total of 339 children and adolescents (response rate 95%) from four pediatric outpatient clinics in the Netherlands with doctor-diagnosed asthma participated. Of the caregivers, 43% reported major or minor psychosocial problems of their child or adolescent which is two times more than in the reference group, whereas the percentage of adolescents reporting psychosocial problems was comparable to a reference population. Adolescents and caregivers reported few impairments in asthma-related QoL (median score between 6.2 and 7.0). However, an optimal asthma-related QoL did not rule out major psychosocial problems: 10% of the adolescents with an optimal asthma-related QoL score reported major psychosocial problems. And in one out of seven children with an optimal caregiver's asthma-related QoL score, major psychosocial problems were reported. The prevalence of psychosocial problems in children and adolescents with asthma is considerable. Assessment of asthma-related QoL alone is insufficient to identify those children with major psychosocial problems. We recommend the implementation of psychosocial screening, besides assessment of asthma-related QoL, in routine pediatric asthma care, to improve asthma management.


Asunto(s)
Trastornos de Adaptación/diagnóstico , Trastornos de Adaptación/epidemiología , Asma/psicología , Calidad de Vida , Conducta Social , Encuestas y Cuestionarios/normas , Trastornos de Adaptación/etiología , Trastornos de Adaptación/psicología , Adolescente , Asma/complicaciones , Asma/epidemiología , Cuidadores , Niño , Femenino , Humanos , Masculino , Países Bajos/epidemiología , Pacientes Ambulatorios , Psicometría , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
8.
Glob Pediatr Health ; 7: 2333794X20958933, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33088852

RESUMEN

In the midst of current SARS-CoV-2 pandemic, little is known about the implications of this new virus on patients with underlying chronic comorbidities. Herein, we present a case of a 5-week-old infant with congenital adrenal hyperplasia who acquired SARS-CoV-2 and recovered with minimal medical support.

9.
Glob Pediatr Health ; 6: 2333794X19845074, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31080849

RESUMEN

Adrenal insufficiency is a rare, potentially life-threatening condition whose diagnosis requires a high index of suspicion. Adrenal insufficiency may be primary, secondary, or tertiary with varied etiologies. Primary insufficiency may be part of a cluster of autoimmune diseases, referred to as autoimmune polyglandular syndrome(s) (APS). We describe a case of a 15-year-old male who presents to a local emergency department complaining of fatigue, fever, abdominal pain, nausea, and vomiting for a few days with a preceding viral illness. The patient was hyponatremic and hyperkalemic with skin hyperpigmentation, raising concern for adrenal insufficiency. Laboratory workup confirmed autoimmune primary adrenal insufficiency, with subsequent laboratory studies revealing autoimmune thyroiditis and celiac disease. Concomitant Addison's and Hashimoto's diseases led to a diagnosis of APS type 2. The patient was started on steroid replacement with rapid clinical improvement.

10.
Ned Tijdschr Geneeskd ; 160: A9794, 2015.
Artículo en Holandés | MEDLINE | ID: mdl-26934438

RESUMEN

An 11-year-old girl with a history of trichophagia presented with abdominal pain and progressive vomiting. The MRI scan showed a gastric mass and multiple masses in the small intestine. A large trichobezoar was removed from the stomach by laparotomy.


Asunto(s)
Dolor Abdominal/diagnóstico , Bezoares/diagnóstico , Bezoares/cirugía , Laparotomía/métodos , Dolor Abdominal/etiología , Niño , Femenino , Humanos , Intestino Delgado , Vómitos/diagnóstico , Vómitos/etiología
11.
J Comp Neurol ; 480(4): 352-63, 2004 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-15558782

RESUMEN

During mating, the female golden hamster displays a stereotyped specific receptive posture, characterized by lordosis of the back, elevation of the tail, and extension of the legs. Muscles involved in this posture are thought to be iliopsoas, cutaneus trunci, lateral longissimus (LL), and quadratus lumborum (QL). Lesion studies in rats suggest that mating behavior is controlled by the mesencephalic periaqueductal gray (PAG). The PAG does not project directly to the motoneurons innervating the muscles involved in mating, but is thought to make use of the nucleus retroambiguus (NRA) as relay. The NRA is located ventrolaterally in the most caudal medulla, and projects directly to iliopsoas and cutaneus trunci motoneuronal cell groups. The question is whether this is also true for LL and QL muscles. Retrograde HRP tracing experiments revealed that LL and QL motoneurons are located medially in the ventral horn of the T12-L6 and T13-L4 segments, respectively. A subsequent ultrastructural study combined wheatgerm agglutinin-conjugated horseradish peroxidase injections in the NRA with cholera-toxin B-subunit injections in LL and QL muscles. The results revealed monosynaptic contacts between anterogradely labeled NRA-fiber terminals with retrogradely labeled dendrites of both LL and QL motoneurons. Almost all these terminals had asymmetrical synapses and contained spherical vesicles, suggesting an excitatory function of this NRA-motoneuronal pathway. These results correspond with the hypothesis that in hamster the PAG-NRA-motoneuronal projection not only involves motoneurons of iliopsoas and cutaneus trunci but also of LL and QL.


Asunto(s)
Bulbo Raquídeo/citología , Neuronas Motoras/ultraestructura , Músculo Esquelético/inervación , Vías Nerviosas/anatomía & histología , Conducta Sexual Animal/fisiología , Médula Espinal/citología , Animales , Copulación/fisiología , Cricetinae , Femenino , Peroxidasa de Rábano Silvestre/análisis , Bulbo Raquídeo/fisiología , Mesocricetus , Neuronas Motoras/citología , Vías Nerviosas/fisiología , Postura/fisiología , Médula Espinal/fisiología , Vértebras Torácicas
12.
Chemistry ; 2(5): 592-597, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-29178225

RESUMEN

Manganese complexes of 2,2'-bipyridine (bpy) and 1,10-phenantroline (phen) have been synthesised in the supercages of cubic NaX and NaY and in the hypercages of the hexagonal NaEMT faujasites. The coordination and redox chemistry were studied with ESCA, CA, FT-IR, FT-Raman, diffuse reflectance and emission techniques. FT-IR/FT-Raman shows cis coordination for all complexes and a high Mn-N stretching frequency in the phen complexes as a result of steric constraints imposed by the ligand. [Mn(bpy)2 ]2+ in the different zeolites shows metal-to-ligand charge transfer (MLCT; at 495 nm); for [Mn(phen)2 ]2+ -NaY the MLCt is broadened owing to complex distortion. On MLCT excitation [Mn(bpy)2 ]2+ complexes show an ipsochromic shift in the emission and an increase in quantum yield with increasing steric restrictions imposed by the zeolite. The ipsochromic shift of the emission band of [Mn(phen)2 ]2+ in NaY results from the combined effect of the ligand field (this suggests emission from a CT state) and of coordinative distortion. The key factor influencing the emission properties is found to be the overall matrix-induced complex distortion. Cation stabilisation of the ligand anion affects emission indirectly. The decay times for [Mn-(bpy)2 ]2+ -NaY are in the millisecond range (7.5-11.5 ms). A proposed model for excitation and emission properties of zeolite-occluded MnII complexes involves excitation of a quartet CT state, intersystem crossing and subsequent emission. The enhanced stability of the coordination sphere in the zeolite allows complexes to luminesce from a CT state, which is not detected in solution. The zeolite behaves as a supramolecular cryptating agent, protecting complexes from photodissociation.

13.
Neurosci Lett ; 362(1): 57-60, 2004 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-15147780

RESUMEN

Although the guinea pig is used widely in experimental medical research, including in studies on micturition control, the spinal origin of preganglionic parasympathetic bladder and somatic external urethral sphincter motoneurons is not known. In the male guinea pig using wheat germ agglutinin-conjugated horseradish peroxidase and dextran Alexa Fluor 488/568 tracers, preganglionic parasympathetic bladder motoneurons were observed in the ventrolateral part of the intermediolateral cell group of the first sacral segment. The external urethral sphincter motoneurons were found to be located in the ventral horn of the first sacral segment, in a cell group corresponding with the nucleus of Onuf in cat and human.


Asunto(s)
Neuronas Motoras/química , Uretra/química , Vejiga Urinaria/química , Animales , Cobayas , Masculino , Neuronas Motoras/fisiología , Uretra/inervación , Vejiga Urinaria/inervación
14.
J Perinatol ; 24(2): 105-8, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14762455

RESUMEN

OBJECTIVE: Traditionally, neonatal thyrotoxicosis has been managed with antithyroid drugs and/or iodine as well as sedatives, propranol and digitalis when necessary. The purpose of this study was to evaluate the management of neonatal thyrotoxicosis using the radio-contrast agent iopanoic acid. METHODS: We managed five cases of neonatal thyrotoxicosis. All infants were treated initially with propranolol (1.7 mg/kg/day) and iopanoic acid 250 to 500 mg every third or fourth day. RESULTS: In all cases, clinical signs improved and T(3) and T(4) levels decreased dramatically within 24 to 72 hours. No toxic side effects were noted. CONCLUSION: Neonatal thyrotoxicosis can be managed successfully using iopanoic acid. Iopanoic acid is essentially free of side effects and need only be administered every 3 to 4 days. When administered until (transplacental) maternal TSI has been metabolized by the neonate, iopanoic acid maintains euthyroid status with no risk of hypothyroidism. With conventional therapy, propylthiouracil (PTU) must be administered three times a day. PTU also carries a significant risk of toxic side effects and a week or more of therapy is required to correct the hyperthyroid state and may induce hypothyroidism.


Asunto(s)
Medios de Contraste/uso terapéutico , Enfermedad de Graves/tratamiento farmacológico , Ácido Yopanoico/uso terapéutico , Antagonistas Adrenérgicos beta/uso terapéutico , Medios de Contraste/administración & dosificación , Humanos , Inmunoglobulinas Estimulantes de la Tiroides/sangre , Recién Nacido , Ácido Yopanoico/administración & dosificación , Propranolol/uso terapéutico
15.
Neurobiol Aging ; 34(4): 1277-86, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23063645

RESUMEN

Brain microvasculature plays a critical role in the regulation of homeostasis of neural tissues. The present study focuses on characteristic microvascular basement membrane (bm) aberrations in the midbrain periaqueductal gray matter (PAG) and their relation to aging. The PAG can be considered a caudal extension of the limbic system and is a key structure in the regulation of a myriad of autonomic and motor control functions. In an ultrastructural study, morphologic changes in mesencephalic PAG capillaries were assessed in aged and young hamster and compared with those in caudal brainstem areas. Bm aberrations were studied in 1200 capillaries (n = 600 young hamsters; n = 600 aged hamsters). A new, never reported variant of bm degeneration was found that presented itself as foamy-like structures accumulating within the lamina densa of notably PAG capillaries. We classified these foamy structures as 'spumiform basement membrane degenerations' (sbmd) in which we could distinguish 4 stages depending on the size and intramembranous localization, ranging from split bm (stage I), intermediate stages II and III, to extensive stage IV, affecting almost the complete capillary bm outline. In the PAG of senescent animals various stages of sbmd were observed in 92 ± 3% of all capillaries. Stage II was most prominently present (59%), followed by stage III (20%), and stage IV (13%). These bm aberrations were clearly age-dependent because in young animals, only 5% of the PAG capillaries showed characteristics of sbmd. For comparison, in the pontine reticular formation at the PAG-level, 41% of the capillaries showed a form of sbmd, but these defects were significantly less severe (stages I-II, 98%), and caudal brainstem structures displayed no sbmd at all. In addition to sbmd, diffuse endothelial changes, disrupted tight junctions, thickening of the bm, pericyte degeneration, and gliosis were observed in PAG capillaries. It is hypothesized that selective bm permeability of PAG capillaries results in a sequence of bm damage events that start with split bm, gradually changing into more and more extensive sbmd accumulations that eventually almost completely surround the capillary. Progressive sbmd in PAG capillaries might lead to a loss of blood-brain barrier function and consequently to impairment of autonomic and motor control functions exerted by the PAG.


Asunto(s)
Membrana Basal/ultraestructura , Tronco Encefálico/irrigación sanguínea , Tronco Encefálico/ultraestructura , Capilares/ultraestructura , Trastornos Cerebrovasculares/patología , Animales , Cricetinae , Femenino , Mesocricetus
16.
Fluids Barriers CNS ; 9(1): 16, 2012 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-22883598

RESUMEN

There is increasing evidence that non-synaptic communication by volume transmission in the flowing CSF plays an important role in neural mechanisms, especially for extending the duration of behavioral effects. In the present review, we explore the mechanisms involved in the behavioral and physiological effects of ß-endorphin (ß-END), especially those involving the cerebrospinal fluid (CSF), as a message transport system to reach distant brain areas. The major source of ß-END are the pro-opio-melano-cortin (POMC) neurons, located in the arcuate hypothalamic nucleus (ARH), bordering the 3rd ventricle. In addition, numerous varicose ß-END-immunoreactive fibers are situated close to the ventricular surfaces. In the present paper we surveyed the evidence that volume transmission via the CSF can be considered as an option for messages to reach remote brain areas. Some of the points discussed in the present review are: release mechanisms of ß-END, independence of peripheral versus central levels, central ß-END migration over considerable distances, behavioral effects of ß-END depend on location of ventricular administration, and abundance of mu and delta opioid receptors in the periventricular regions of the brain.

17.
Eur J Radiol ; 81(4): e524-30, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21733649

RESUMEN

AIMS: To assess the accuracy of surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols. MATERIALS AND METHODS: Seven fresh-frozen cadaver heads were used. There was no conflict of interests in this study. CBCT scans were made of the heads and 3D surface models were created of the mandible using two different segmentation protocols. The one series of 3D models was segmented by a commercial software company, while the other series was done by an experienced 3D clinician. The heads were then macerated following a standard process. A high resolution laser surface scanner was used to make a 3D model of the macerated mandibles, which acted as the reference 3D model or "gold standard". The 3D models generated from the two rendering protocols were compared with the "gold standard" using a point-based rigid registration algorithm to superimpose the three 3D models. The linear difference at 25 anatomic and cephalometric landmarks between the laser surface scan and the 3D models generate from the two rendering protocols was measured repeatedly in two sessions with one week interval. RESULTS: The agreement between the repeated measurement was excellent (ICC=0.923-1.000). The mean deviation from the gold standard by the 3D models generated from the CS group was 0.330mm±0.427, while the mean deviation from the Clinician's rendering was 0.763mm±0.392. The surface models segmented by both CS and DS protocols tend to be larger than those of the reference models. In the DS group, the biggest mean differences with the LSS models were found at the points ConLatR (CI: 0.83-1.23), ConMedR (CI: -3.16 to 2.25), CoLatL (CI: -0.68 to 2.23), Spine (CI: 1.19-2.28), ConAntL (CI: 0.84-1.69), ConSupR (CI: -1.12 to 1.47) and RetMolR (CI: 0.84-1.80). CONCLUSION: The Commercially segmented models resembled the reality more closely than the Doctor's segmented models. If 3D models are needed for surgical drilling guides or surgical planning which requires high precision, the additional cost of the commercial segmentation services seem to be justified to produce a more accurate surface models.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Imagenología Tridimensional/métodos , Mandíbula/anatomía & histología , Mandíbula/diagnóstico por imagen , Modelos Anatómicos , Reconocimiento de Normas Patrones Automatizadas/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Algoritmos , Cadáver , Simulación por Computador , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Omega (Westport) ; 66(1): 57-77, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23495537

RESUMEN

In The Netherlands, the number of body donor registrations has been increasing for several years. Body donors are people who register at an anatomical institute to donate their entire body, after death, for scientific education and research. Although only 0.1% of the Dutch population is registered as a body donor, this is sufficient to realize the anatomical demand of about 650 bodies annually. Due to the recent rise of registrations many anatomical institutes have (temporarily) stopped registering new donors to prevent a surplus of bodies. Based on a large body donor survey (n=759) and in-depth anthropological interviews with 20 body donors, we try to give an explanation for the rising registration numbers. We argue that the choice for body donation in contemporary, individualized Dutch society is an autonomous way to give meaning and sense to life and death outside the framework of institutionalized religion.


Asunto(s)
Actitud Frente a la Muerte , Donaciones , Cuerpo Humano , Sistema de Registros/estadística & datos numéricos , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Adulto , Anciano , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Países Bajos , Opinión Pública
19.
Neurobiol Aging ; 33(3): 625.e1-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21550695

RESUMEN

Lipofuscin accumulation is a characteristic feature of senescent postmitotic neuronal cells but estrogen may have protecting effects by inhibiting its formation. In the present ultrastructural study, lipofuscin accumulation was studied in 2 estrogen-α-receptive brainstem areas: nucleus pararetroambiguus (NPRA) and the commissural part of the solitary tract nucleus/A2 catecholaminergic group (NTScom/A2) and compared with the estrogen-insensitive medial tegmental field (mtf), in young (23 weeks) and aged (95 weeks) female hamsters. In the aged animals, extensive intracytoplasmic lipofuscin accumulation was observed. A total number of 6450 neurons were classified in 4 categories. Levels were significantly elevated in each of the brain areas studied. Lipofuscin accumulation was strongest in the mtf, less in NPRA, and remarkably less in the area of NTScom/A2. In conclusion, the observed differences in lipofuscin accumulation suggest: (1) considerable regional differences in the degree of neuronal vulnerability; and (2) a possible neuroprotective role for estrogen, because the degree of accumulation is inversely related to the density of the estrogen receptors, varying from nonreceptive (mtf) to NPRA and NTScom/A2 (most receptive).


Asunto(s)
Envejecimiento/metabolismo , Tronco Encefálico/metabolismo , Lipofuscina/metabolismo , Neuronas/metabolismo , Envejecimiento/fisiología , Animales , Tronco Encefálico/fisiología , Senescencia Celular/fisiología , Cricetinae , Gránulos Citoplasmáticos/metabolismo , Gránulos Citoplasmáticos/fisiología , Receptor alfa de Estrógeno/metabolismo , Femenino , Masculino , Mesocricetus , Neuronas/fisiología
20.
Neurobiol Aging ; 33(12): 2920-34, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22445324

RESUMEN

UNLABELLED: The nucleus pararetroambiguus (NPRA) and the commissural nucleus of the solitary tract (NTScom) show estrogen nuclear receptor-α immunoreactivity (nuclear ER-α-IR). Both cell groups are involved in estrous cycle related adaptations. We examined in normally cycling aged hamsters the occurrence/amount/frequency of age-related degenerative changes in NPRA and NTScom during estrus and diestrus. In 2640 electron microscopy photomicrographs plasticity reflected in the ratio of axon terminal surface/dendrite surface (t/d) was morphometrically analyzed. Medial tegmental field (mtf, nuclear ER-α-IR poor), served as control. In aged animals, irrespective of nuclear ER-α-IR+ or nuclear ER-α-IR- related cell groups, extensive diffuse degenerative structural aberrations were observed. The hormonal state had a strong influence on t/d ratios in NPRA and NTScom, but not in mtf. In NPRA and NTScom, diestrous hamsters had significantly smaller t/d ratios (NPRA, 0.750 ± 0.050; NTScom, 0.900 ± 0.039) than the estrous hamsters (NPRA, 1.083 ± 0.075; NTScom, 1.204 ± 0.076). Aging affected axodendritic ratios only in mtf (p < 0.001). IN CONCLUSION: in the female hamster brain, estrous cycle-induced structural plasticity is preserved in NPRA and NTScom during aging despite the presence of diffuse age-related neurodegenerative changes.


Asunto(s)
Envejecimiento , Tronco Encefálico/citología , Estrógenos/metabolismo , Neuronas/metabolismo , Conducta Sexual Animal/fisiología , Factores de Edad , Animales , Tronco Encefálico/metabolismo , Cricetinae , Receptor alfa de Estrógeno/metabolismo , Ciclo Estral/metabolismo , Femenino , Masculino , Microscopía Electrónica de Transmisión , Neuronas/ultraestructura , Factores de Tiempo
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