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1.
Sci Rep ; 14(1): 10803, 2024 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734771

RESUMEN

The northern giant hornet Vespa mandarinia (NGH) is a voracious predator of other insect species, including honey bees. NGH's native range spans subtropical and temperate regions across much of east and southeast Asia and, in 2019, exotic populations of the species were discovered in North America. Despite this broad range and invasive potential, investigation of the population genomic structure of NGH across its native and introduced ranges has thus far been limited to a small number of mitochondrial samples. Here, we present analyses of genomic data from NGH individuals collected across the species' native range and from exotic individuals collected in North America. We provide the first survey of whole-genome population variation for any hornet species, covering this species' native and invasive ranges, and in doing so confirm likely origins in Japan and South Korea for the two introductions. We additionally show that, while this introduced population exhibited strongly elevated levels of inbreeding, these signatures of inbreeding are also present in some long-standing native populations, which may indicate that inbreeding depression alone is insufficient to prevent the persistence of NGH populations. As well as highlighting the importance of ongoing monitoring and eradication efforts to limit the spread of this species outside of its natural range, our data will serve as a foundational database for future genomic studies into introduced hornet populations.


Asunto(s)
Especies Introducidas , Avispas , Animales , América del Norte , Avispas/genética , Genética de Población , Genómica/métodos , Variación Genética , Endogamia , Genoma de los Insectos
2.
Mol Ecol ; 33(2): e17217, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38014715

RESUMEN

Social insect reproductives and non-reproductives represent ideal models with which to understand the expression and regulation of alternative phenotypes. Most research in this area has focused on the developmental regulation of reproductive phenotypes in obligately social taxa such as honey bees, while relatively few studies have addressed the molecular correlates of reproductive differentiation in species in which the division of reproductive labour is established only in plastic dominance hierarchies. To address this knowledge gap, we generate the first genome for any stenogastrine wasp and analyse brain transcriptomic data for non-reproductives and reproductives of the facultatively social species Liostenogaster flavolineata, a representative of one of the simplest forms of social living. By experimentally manipulating the reproductive 'queues' exhibited by social colonies of this species, we show that reproductive division of labour in this species is associated with transcriptomic signatures that are more subtle and variable than those observed in social taxa in which colony living has become obligate; that variation in gene expression among non-reproductives reflects their investment into foraging effort more than their social rank; and that genes associated with reproductive division of labour overlap to some extent with those underlying division of labour in the separate polistine origin of wasp sociality but only explain a small portion of overall variation in this trait. These results indicate that broad patterns of within-colony transcriptomic differentiation in this species are similar to those in Polistinae but offer little support for the existence of a strongly conserved 'toolkit' for sociality.


Asunto(s)
Avispas , Abejas/genética , Animales , Avispas/genética , Conducta Social , Predominio Social , Perfilación de la Expresión Génica , Transcriptoma/genética , Reproducción/genética
3.
Int J Biol Macromol ; 242(Pt 1): 124568, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37100315

RESUMEN

The extreme conservation of mitochondrial genomes in metazoans poses a significant challenge to understanding mitogenome evolution. However, the presence of variation in gene order or genome structure, found in a small number of taxa, can provide unique insights into this evolution. Previous work on two stingless bees in the genus Tetragonula (T. carbonaria and T. hockingsi) revealed highly divergent CO1 regions between them and when compared to the bees from the same tribe (Meliponini), indicating rapid evolution. Using mtDNA isolation and Illumina sequencing, we elucidated the mitogenomes of both species. In both species, there has been a duplication of the whole mitogenome to give a total genome size of 30,666 bp in T. carbonaria; and 30,662 bp in T. hockingsi. These duplicated genomes present a circular structure with two identical and mirrored copies of all 13 protein coding genes and 22 tRNAs, with the exception of a few tRNAs that are present as single copies. In addition, the mitogenomes are characterized by rearrangements of two block of genes. We believe that rapid evolution is present in the whole Indo-Malay/Australasian group of Meliponini but is extraordinarily elevated in T. carbonaria and T. hockingsi, probably due to founder effect, low effective population size and the mitogenome duplication. All these features - rapid evolution, rearrangements, and duplication - deviate significantly from the vast majority of the mitogenomes described so far, making the mitogenomes of Tetragonula unique opportunities to address fundamental questions of mitogenome function and evolution.


Asunto(s)
Abejas , Genoma Mitocondrial , Animales , Australia , Abejas/genética , Genoma Mitocondrial/genética , Mitocondrias/genética , Filogenia
4.
Sci Rep ; 13(1): 1640, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717606

RESUMEN

Social insects are very successful invasive species, and the continued increase of global trade and transportation has exacerbated this problem. The yellow-legged hornet, Vespa velutina nigrithorax (henceforth Asian hornet), is drastically expanding its range in Western Europe. As an apex insect predator, this hornet poses a serious threat to the honey bee industry and endemic pollinators. Current suppression methods have proven too inefficient and expensive to limit its spread. Gene drives might be an effective tool to control this species, but their use has not yet been thoroughly investigated in social insects. Here, we built a model that matches the hornet's life history and modelled the effect of different gene drive scenarios on an established invasive population. To test the broader applicability and sensitivity of the model, we also incorporated the invasive European paper wasp Polistes dominula. We find that, due to the haplodiploidy of social hymenopterans, only a gene drive targeting female fertility is promising for population control. Our results show that although a gene drive can suppress a social wasp population, it can only do so under fairly stringent gene drive-specific conditions. This is due to a combination of two factors: first, the large number of surviving offspring that social wasp colonies produce make it possible that, even with very limited formation of resistance alleles, such alleles can quickly spread and rescue the population. Second, due to social wasp life history, infertile individuals do not compete with fertile ones, allowing fertile individuals to maintain a large population size even when drive alleles are widespread. Nevertheless, continued improvements in gene drive technology may make it a promising method for the control of invasive social insects in the future.


Asunto(s)
Tecnología de Genética Dirigida , Avispas , Femenino , Abejas/genética , Animales , Avispas/genética , Europa (Continente) , Fertilidad , Especies Introducidas
5.
Front Insect Sci ; 3: 1145158, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38469472

RESUMEN

Hornets are large, predatory wasps that have the potential to alter biotic communities and harm honey bee colonies once established in non-native locations. Mated, diapausing females (gynes) can easily be transported to new habitats, where their behavioral flexibility allows them to found colonies using local food and nest materials. Of the 22 species in the genus Vespa, five species are now naturalized far from their endemic populations and another four have been detected either in nature or during inspections at borders of other countries. By far the most likely pathway of long-distance dispersal is the transport of gynes in transoceanic shipments of goods. Thereafter, natural dispersal of gynes in spring and accidental local transport by humans cause shorter-range expansions and contribute to the invasion process. Propagule pressure of hornets is unquantified, although it is likely low but unrelenting. The success of introduced populations is limited by low propagule size and the consequences of genetic founder effects, including the extinction vortex linked to single-locus, complementary sex determination of most hymenopterans. Invasion success is enhanced by climatic similarity between source locality and introduction site, as well as genetic diversity conferred by polyandry in some species. These and other factors that may have influenced the successful establishment of invasive populations of V. velutina, V. tropica, V. bicolor, V. orientalis, and V. crabro are discussed. The highly publicized detections of V. mandarinia in North America and research into its status provide a real-time example of an unfolding hornet invasion.

6.
Front Insect Sci ; 3: 1253176, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38469527

RESUMEN

[This corrects the article DOI: 10.3389/finsc.2023.1145158.].

7.
Nat Commun ; 12(1): 775, 2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33536437

RESUMEN

Phenotypic plasticity, the ability to produce multiple phenotypes from a single genotype, represents an excellent model with which to examine the relationship between gene expression and phenotypes. Analyses of the molecular foundations of phenotypic plasticity are challenging, however, especially in the case of complex social phenotypes. Here we apply a machine learning approach to tackle this challenge by analyzing individual-level gene expression profiles of Polistes dominula paper wasps following the loss of a queen. We find that caste-associated gene expression profiles respond strongly to queen loss, and that this change is partly explained by attributes such as age but occurs even in individuals that appear phenotypically unaffected. These results demonstrate that large changes in gene expression may occur in the absence of outwardly detectable phenotypic changes, resulting here in a socially mediated de-differentiation of individuals at the transcriptomic level but not at the levels of ovarian development or behavior.


Asunto(s)
Adaptación Fisiológica/genética , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Conducta Social , Transcriptoma/genética , Avispas/genética , Algoritmos , Animales , Femenino , Ontología de Genes , Redes Reguladoras de Genes , Humanos , Aprendizaje Automático , Fenotipo
8.
Curr Opin Insect Sci ; 34: 40-47, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31247416

RESUMEN

Major evolutionary transitions in individuality are characterised by the formation of new levels of biological complexity from the cooperation of previously independent lower-level units. The evolution of superorganismality in insects is one such major transition, and is characterised by an extreme division of reproductive labour between ancestrally autonomous units, in the form of queen and worker castes. Here, we discuss the nature of plasticity in the emergence of castes across the major transition to superorganismality in insects. We identify key changes in plasticity which act at different levels of selection: a loss of reproductivity plasticity at the individual level is matched by a gain in plasticity at the colony level. Taking multi-level selection into consideration has important implications for formulating testable hypotheses regarding the nature of plasticity in a major transition from a lower to a higher level of biological complexity.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Insectos/fisiología , Selección Genética , Conducta Social , Animales , Reproducción , Conducta Sexual Animal
9.
Plast Reconstr Surg Glob Open ; 5(4): e1299, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28507861

RESUMEN

Radial forearm free flaps are commonly used for soft-tissue reconstruction after resection of head and neck cancer. It is perfused by the radial artery, leaving the ulnar artery for perfusion of the hand and digits. The absence of distal ulnar artery and associated superficial palmar arch, however, has not been reported in cadaveric dissection. We report a case of unilateral ulnar artery flow absence, detected by Allen's test, during preoperative preparation for a radial forearm free flap. Based on the simplicity, safety, and ease, we recommend Allen's test to be performed preoperatively on every patient for whom such a flap is a consideration.

10.
Laryngoscope ; 127(7): E212-E218, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28485552

RESUMEN

OBJECTIVES/HYPOTHESIS: Mandibular distraction osteogenesis (MDO) involves a lengthy consolidation phase where complications can occur. Strontium is an element that has been shown to improve bone healing. The objective of this study was to determine whether strontium citrate can be used to enhance bone healing during MDO in a rabbit model. STUDY DESIGN: Prospective animal model study. METHODS: Custom-made MDO devices were placed on 20 New Zealand White rabbits. After a 7-day latency period, distraction was performed at 1 mm/day for 5 days. The study group rabbits (n = 10) received oral strontium citrate; the other 10 rabbits served as controls. Mandibles were removed at the end of the consolidation period (4 weeks). Formation and healing of new bone were evaluated with microcomputed tomography, histology, and a three-point bending mechanical test. RESULTS: New bone formed in all animals, but the consolidation process was enhanced in rabbits that received strontium. The histological analysis showed that study group rabbits had more mature bone. Microcomputed tomographic images demonstrated significantly higher bone density for study group animals, and the three-point bending test results demonstrated that the maximum load of the study group specimens was significantly greater than that of the control group mandibles. CONCLUSIONS: Strontium citrate improved the formation of new bone in the current rabbit model of MDO. The prolonged consolidation period may be shortened with strontium citrate, which may also have the potential to reduce complications. LEVEL OF EVIDENCE: NA Laryngoscope, 127:E212-E218, 2017.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Citratos/farmacología , Modelos Animales de Enfermedad , Mandíbula/efectos de los fármacos , Mandíbula/cirugía , Osteogénesis por Distracción/métodos , Estroncio/farmacología , Animales , Densidad Ósea/efectos de los fármacos , Mandíbula/patología , Conejos , Microtomografía por Rayos X
11.
Laryngoscope ; 126 Suppl 5: S5-S13, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27233057

RESUMEN

OBJECTIVES/HYPOTHESIS: To date, there has been little research on shared decision making and decisional outcomes in pediatric surgery. The objectives of this study were to describe the level of decisional conflict and decisional regret experienced by parents considering otoplasty for their children, and to determine if they are related to perceptions of shared decision making. STUDY DESIGN: Prospective cohort clinical study. METHODS: Sixty-five consecutive parents of children who underwent surgical consultation for otoplasty were prospectively enrolled. Participants completed the Demographic Form, the Decisional Conflict Scale, and the Shared Decision-Making Questionnaire after the consultation visit. The consulting surgeons completed the physician version of the Shared Decision-Making Questionnaire. Six months after surgery, parents completed the Decisional Regret Scale. RESULTS: The median decisional conflict was 15.63; 21 (32.8%) parents scored 25 or above, a previously defined cutoff indicating clinically significant decisional conflict. Parent ratings of shared decision making and decisional conflict were significantly negatively correlated (P < 0.001); however, there was no significant correlation between physician ratings of shared decision making and parental decisional conflict. Significant decisional regret was reported in two (3.2%) participants. Decisional regret and parent and physician ratings of shared decision making were both significantly negatively correlated (P = 0.044 and P = 0.001, respectively). Decisional regret and decisional conflict scores were significantly positively correlated (P = 0.001). Parent and physician ratings of shared decision making were correlated (intraclass correlation = 0.625, P < 0.001). CONCLUSION: Many parents experienced significant decisional conflict when making decisions about their child's elective surgical treatment. Fewer parents experienced significant decisional regret after the procedure. Parents who perceived themselves as being more involved in the decision making process reported less decisional conflict and decisional regret. Parents and physicians had varied perceptions of the degree of shared decision making. Future research should develop interventions to increase parents' involvement in decision making and explore the influence of significant decisional conflict and decisional regret on health outcomes. LEVEL OF EVIDENCE: 2b. Laryngoscope, 126:S5-S13, 2016.


Asunto(s)
Toma de Decisiones , Oído Externo/cirugía , Procedimientos Quirúrgicos Electivos , Padres , Cirugía Plástica , Niño , Humanos , Complicaciones Posoperatorias , Estudios Prospectivos , Encuestas y Cuestionarios
12.
J Craniofac Surg ; 27(2): 477-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26967081

RESUMEN

Otoplasty is a commonly performed procedure to correct prominent ears. Many different otoplasty techniques have been described but there is no gold standard technique. As well, many different suture materials are used in otoplasty but studies directly comparing different sutures materials are lacking. An otoplasty outcome study with Nylon and Mersilene (2 of the most commonly used sutures in otoplasty) sutures was conducted using a rabbit model. Each rabbit ear was randomized to receive a Mustardé-type horizontal mattress suture with either 4-0 clear Nylon (N = 12 ears) or 4-0 Mersilene sutures (N = 12 ears). Two weeks after surgery, the auricular bend angle was measured with a finger goniometer and histologic analysis with hematoxylin and eosin staining was performed on the rabbit auricular cartilage. Overall, there was no significant difference in the mean bend angle between the 2 groups (Nylon: 135.8°, SD = 22.7° and Mersilene: 143.2°, SD = 19.7°; P = 0.559). Also, no qualitative difference was observed on histologic analysis between the 2 suture groups. In the current rabbit model study, both Nylon and Mersilene sutures performed well and no significant differences were noted.


Asunto(s)
Materiales Biocompatibles/química , Oído Externo/cirugía , Procedimientos de Cirugía Plástica/métodos , Suturas , Animales , Cartílago Auricular/patología , Cartílago Auricular/fisiología , Cartílago Auricular/cirugía , Oído Externo/patología , Oído Externo/fisiología , Masculino , Modelos Animales , Nylons/química , Docilidad , Tereftalatos Polietilenos/química , Conejos , Distribución Aleatoria , Procedimientos de Cirugía Plástica/instrumentación
13.
J Otolaryngol Head Neck Surg ; 45: 16, 2016 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-26921257

RESUMEN

BACKGROUND: Fine needle aspiration (FNA) cytopathology is the gold standard work-up for thyroid nodules. However, indeterminate lesions are encountered commonly and can lead to difficult treatment decisions. We sought to determine whether patients experienced decisional conflict surrounding management with diagnostic thyroidectomy in the setting of indeterminate FNA results. METHODS: Patients with indeterminate results of thyroid nodule FNA were prospectively enrolled. All consultations were carried out by three otolaryngologists in a consistent manner. After consultation, participants completed a demographics form and the Decisional Conflict Scale (DCS) questionnaire. RESULTS: Thirty-five patients (28 female) between the ages of 30 and 88 years (mean age 54.89) participated. The median total DCS score was 10.94 (interquartile range, 4.69-25.0). Twelve patients (34%) scored at or above 25 on the DCS, indicating clinically significant level of decisional conflict. Patients reported feeling significantly more confident about their decision after the surgical consultation compared to before the consultation (p = 0.00). The total DCS score was significantly negatively correlated with self-reported confidence after the consultation (r = -0.421, p = 0.012). CONCLUSION: Many patients experienced clinically significant decisional conflict when considering thyroidectomy for management of a thyroid nodule with indeterminate cytopathology. Future research should be directed at developing decision support tools for this patient group, and exploring the impact of decisional conflict on health outcomes.


Asunto(s)
Biopsia con Aguja Fina/métodos , Toma de Decisiones , Derivación y Consulta , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo/diagnóstico , Tiroidectomía/psicología , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Encuestas y Cuestionarios , Neoplasias de la Tiroides/cirugía , Nódulo Tiroideo/cirugía , Tiroidectomía/métodos
14.
J Otolaryngol Head Neck Surg ; 45: 13, 2016 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26869258

RESUMEN

BACKGROUND: Eustachian tube dysfunction (ETD) is a common medical issue, occurring in at least 1% of the adult population. Patients suffering from ET dysfunction typically present with complaints of hearing loss or sensation of pressure or plugged ear, which can lead to impaired quality of life. Over time ETD can result in conductive hearing loss or choleastatoma formation. Effective theraputic options for ET dysfunction are few. Eustachian tube balloon dilation is a novel surgical technique being used to treat ETD. The aim of our study is to objectively measure the success of Eustachian tube balloon dilation by comparing pre and post-operative middle ear pressures using tympanometric testing. METHODS: RA retrospective chart review was preformed on all patients who underwent balloon dilation of the Eustachian tube by authors NC or MB from 2010 to 2014. Pre and post-operative tympanograms were analyzed and categorized based on type (Type A, Type B, Type C). Success was defined by an improvement in tympanogram type: Type B or C to Type A, or Type B to type C. Pre and post-operative tympanograms were further analyzed using middle ear pressure values. Follow-up ranged from 3 to 15 months. RESULTS: Twenty-five ears (18 patients) were included in the study. Overall 36% of ears had improvement in tympanogram type, and 32% had normalization of tympanogram post-operatively. The Jerger tympanogram type improved significantly following the procedure (p = 0.04). Patients also had statistically significant improvement in measured middle ear pressure post-operatively (P = 0.003). CONCLUSION: The natural history of Eustachian tube dysfunction is poorly understood, and evidence for current treatments are limited. Eustachian tube balloon dilation is a safe procedure, and produces significant improvement in tympanogram values up to 15 months post-operatively. Further refinement of patient selection and standardization of technique is required to optimize the effect of this therapy. Longterm follow-up data will clarify the persistence of the effect.


Asunto(s)
Pruebas de Impedancia Acústica/métodos , Dilatación/métodos , Enfermedades del Oído/terapia , Trompa Auditiva/fisiopatología , Adolescente , Adulto , Anciano , Enfermedades del Oído/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Adulto Joven
15.
J Invertebr Pathol ; 101(1): 77-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19373971

RESUMEN

Deformed wing virus (DWV) in western honey bees (Apis mellifera) often remains asymptomatic in workers and drones, and symptoms have never been described from queens. However, intense infections linked to parasitism by the mite Varroa destructor can cause worker wing deformity and death within 67 h of emergence. Ten workers (eight with deformed wings and two with normal wings) and three drones (two with deformed wings and one with normal wings) from two colonies infected with V. destructor from Nova Scotia, Canada, and two newly-emerged queens (one with deformed wings and one with normal wings) from two colonies infected with V. destructor from Prince Edward Island, Canada, were genetically analyzed for DWV. We detected DWV in all workers and drones, regardless of wing morphology, but only in the deformed-winged queen. This is the first report of DWV from Atlantic Canada and the first detection of a symptomatic queen with DWV from anywhere.


Asunto(s)
Abejas/virología , Picornaviridae/aislamiento & purificación , Animales , Abejas/anatomía & histología , Abejas/parasitología , Canadá , Femenino , Ácaros/virología , Picornaviridae/genética , Alas de Animales/anatomía & histología , Alas de Animales/virología
16.
J Neurosci ; 28(11): 2827-36, 2008 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-18337413

RESUMEN

The mitochondrial metalloprotease AFG3L2 assembles with the homologous protein paraplegin to form a supracomplex in charge of the essential protein quality control within mitochondria. Mutations of paraplegin cause a specific axonal degeneration of the upper motoneuron and, therefore, hereditary spastic paraplegia. Here we present two Afg3l2 murine models: a newly developed null and a spontaneous mutant that we found carrier of a missense mutation. Contrasting with the mild and late onset axonal degeneration of paraplegin-deficient mouse, Afg3l2 models display a marked impairment of axonal development with delayed myelination and poor axonal radial growth leading to lethality at P16. The increased severity of the Afg3l2 mutants is explained by two main molecular features that differentiate AFG3L2 from paraplegin: its higher neuronal expression and its versatile ability to support both hetero-oligomerization and homo-oligomerization. Our data assign to AFG3L2 a crucial role by linking mitochondrial metabolism and axonal development. Moreover, we propose AFG3L2 as an excellent candidate for motoneuron and cerebellar diseases with early onset unknown etiology.


Asunto(s)
Adenosina Trifosfatasas/biosíntesis , Axones/enzimología , Mitocondrias/enzimología , Proteínas Mitocondriales/biosíntesis , Proteasas ATP-Dependientes , ATPasas Asociadas con Actividades Celulares Diversas , Adenosina Trifosfatasas/genética , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos , Axones/patología , Axones/fisiología , Ratones , Ratones Mutantes , Mitocondrias/genética , Mitocondrias/patología , Proteínas Mitocondriales/genética , Datos de Secuencia Molecular
17.
Genomics ; 88(2): 196-203, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16697553

RESUMEN

We identified a new spontaneous recessive mutation in the mouse, mhyp (mosaic hypopigmentation), in a screen for novel proviral integration sites in a multiple ecotropic provirus mapping stock. Integration of an 8.4-kb retrovirus results in mosaic loss of coat pigment in mhyp homozygotes. Patchy loss of pigmentation in the retinal pigmented epithelial layer of the eye with abnormal melanosomes is also evident. We mapped mhyp to mouse chromosome 7 and cloned the underlying gene. mhyp is a defect in the Trappc6a gene. Expression of Trappc6a is markedly diminished in mhyp homozygotes. The normal protein, TRAPPC6A, is a subunit of the TRAPP (transport protein particle) I and II complexes. While TRAPP complexes are essential for ER-to-Golgi and intra-Golgi vesicle trafficking in yeast, TRAPP subunits participate in additional, including post-Golgi, transport events in mammals. The data implicate mammalian TRAPPC6A in vesicle trafficking during melanosome biogenesis.


Asunto(s)
Color del Cabello , Proteínas de la Membrana/genética , Proteínas de Transporte Vesicular/genética , Secuencia de Aminoácidos , Animales , Mapeo Cromosómico , Clonación Molecular , ADN/metabolismo , Color del Cabello/genética , Metilación , Ratones , Ratones Congénicos , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Mutación , Subunidades de Proteína/genética , ARN/metabolismo , Alineación de Secuencia , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/metabolismo
18.
Eur Spine J ; 14(9): 849-53, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15756608

RESUMEN

To determine prevalence and significance of abnormal superficial abdominal reflexes (SARs) in idiopathic scoliosis. Study of 73 patients with presumed idiopathic scoliosis referred for magnetic resonance imaging (MRI), either as a routine pre-operative assessment (n=42) or because of abnormal symptoms or neurological signs (n=31). All patients were examined prior to magnetic resonance imaging (MRI), and the presence of abnormal SARs was noted. All patients then underwent MRI of the whole spine from the foramen magnum to the sacrum. The presence of Chiari 1 malformation and syrinx was recorded. The study group consisted of 11 males and 62 females with a mean age at time of MRI of 18 years (range 5-51 years) and a mean Cobb angle of 48 degrees (range 10-104 degrees). Abnormality of the SARs was recorded in eight cases (prevalence 11%). An abnormal MRI study was recorded in nine cases (12.3%), all patients having a syrinx and four having in addition, a Chiari 1 malformation. Of the patients with abnormal SARs, only 2 (25%) had an abnormal MRI study; 1 had unilateral absence of the reflexes whereas the other had complete absence of SARs. Of patients referred for MRI as a routine pre-operative assessment, 5 (11.6%) had an abnormal MRI study. In patients with idiopathic scoliosis, abnormality of the SARs was recorded in 11% of cases. Unilateral absence was present in one case only and was associated with the presence of syrinx. Other patterns of abnormality were not a useful indicator of underlying cord abnormality.


Asunto(s)
Reflejo Abdominal/fisiología , Reflejo Anormal/fisiología , Escoliosis/fisiopatología , Médula Espinal/fisiopatología , Adolescente , Adulto , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Escoliosis/complicaciones
19.
Eur Spine J ; 12(4): 378-85, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12734742

RESUMEN

The availability of lumbar interbody cages has fuelled renewed interest in interbody fusion. Despite this, there is no consensus regarding the best non-invasive method for evaluation of interbody fusion, especially where cages have been used. The purpose of this study was to determine whether high-quality thin-slice (1- to 3-mm) computed tomography (CT) scans allow proper evaluation of interbody fusion through titanium cages. Patients undergoing lumbar interbody fusion were prospectively evaluated with CT scan and plain radiographs 6 months following surgery. These images were blindly and independently evaluated by a consultant radiologist and a spine research fellow, for bridging bony trabeculation both through and surrounding the cages as well as for changes at the cage endplate interface. Fifty-three patients (156 cages) undergoing posterior lumbar interbody fusion using titanium interbody cages were evaluated. Posterior elements were used to pack the cages and no graft was packed outside the cages. The outcome data were analysed using the Kappa co-efficient and chi-squared analysis. On CT scan, both observers noted bridging trabeculation in 95% of the cages (Kappa 0.85), while on radiographs this was present in only 4% (Kappa 0.74). Both observers also identified bridging trabeculation surrounding the cages on CT scan in 90% of cages (Kappa 0.82), while on the radiographs this was 8% (Kappa 0.86). Radiographs also failed to demonstrate all the loose cages. The results of the study show that high-quality CT scans show images suggesting bridging bony trabeculae following the use of titanium interbody cages. They also appear to show consistent bone outside the cages in spite of no bone graft having been used, and they appear to be better than plain radiographs in the early detection of cage loosening.


Asunto(s)
Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Fusión Vertebral/instrumentación , Tomografía Computarizada por Rayos X , Femenino , Estudios de Seguimiento , Humanos , Dolor de la Región Lumbar/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Fusión Vertebral/métodos , Factores de Tiempo , Titanio
20.
Spine (Phila Pa 1976) ; 28(3): 272-5, 2003 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-12567030

RESUMEN

STUDY DESIGN: The location of pedicle screws in relation to adjacent superior segment facet joints in 106 patients after lumbar spinal fusion was assessed using computed tomography and plain radiographs. OBJECTIVES: To document the incidence of adjacent superior segment facet joint violation following transpedicular instrumentation in the lumbar spine. SUMMARY OF BACKGROUND DATA: Review of the literature failed to show any documented study examining this incidence. METHODS: A total of 106 patients (212 top-level facet screws) undergoing lumbar spinal fusion surgery using transpedicular instrumentation between 1996 and 1999 were prospectively evaluated with a computed tomography scan and plain radiographs at 6 months following surgery. These were blindly and independently evaluated by a consultant radiologist and a spinal research fellow to document the incidence of superior segment facet joint violation. Calculation of the kappa coefficient and chi2 analysis were carried out. RESULTS: The spinal research fellow noted the incidence of facet joint violation on the computed tomography scan to be present in 20% of the screws and 32% of the patients, whereas the consultant radiologist noted this to be the case in 23% and 35%, respectively. The kappa coefficient for computed tomography scan was 0.88, whereas for the plain radiographs it was 0.39. The incidence of facet joint violation was noted to be independent of the sex, level, and diagnosis. There was also an almost uniform incidence in each of the years from 1996 to 1999. CONCLUSION: Facet joint violation occurred in just >30% of the patients and 20% of the screws in this study. This, therefore, raises the theoretical possibility of long-term deterioration in the clinical results following the use of transpedicular instrumentation.


Asunto(s)
Tornillos Óseos/efectos adversos , Vértebras Lumbares/cirugía , Fusión Vertebral/efectos adversos , Fusión Vertebral/instrumentación , Articulación Cigapofisaria/cirugía , Tornillos Óseos/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Variaciones Dependientes del Observador , Estudios Prospectivos , Prótesis e Implantes/estadística & datos numéricos , Reoperación , Factores de Riesgo , Enfermedades de la Columna Vertebral/cirugía , Tomografía Computarizada por Rayos X
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