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1.
Mar Environ Res ; 193: 106256, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38006852

RESUMO

Widespread habitat-forming invaders inhabiting marinas, such as the spaghetti bryozoan Amathia verticillata, allow exploring facilitation processes across spatiotemporal contexts. Here we investigate the role of this bryozoan as habitat for native and exotic macrofaunal assemblages across different ecoregions of Western Mediterranean and East Atlantic coasts, and a monthly variation over a year. While only 7 (all peracarid crustaceans) of the 54 associated species were NIS, they dominated macrofaunal assemblages in terms of abundance, raising the potential for invasional meltdown. NIS richness and community structure differed among marinas but not among ecoregions, highlighting the importance of marina singularities in modulating facilitation at spatial scale. Despite facilitation did not depend on bryozoan abundance fluctuations, it was affected by its deciduous pattern, peaking in summer and disappearing in late winter. Monitoring A. verticillata in marinas, especially in summer periods, may improve the detection and management of multiple associated NIS.


Assuntos
Briozoários , Animais , Espécies Introduzidas , Ecossistema , Crustáceos , Alimentos
2.
Nat Commun ; 13(1): 4796, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35970856

RESUMO

In the context of visual attention, it has been classically assumed that missing the response to a target or erroneously selecting a distractor occurs as a consequence of the (miss)allocation of attention in space. In the present paper, we challenge this view and provide evidence that, in addition to encoding spatial attention, prefrontal neurons also encode a distractibility-to-impulsivity state. Using supervised dimensionality reduction techniques in prefrontal neuronal recordings in monkeys, we identify two partially overlapping neuronal subpopulations associated either with the focus of attention or overt behaviour. The degree of overlap accounts for the behavioral gain associated with the good allocation of attention. We further describe the neural variability accounting for distractibility-to-impulsivity behaviour by a two dimensional state associated with optimality in task and responsiveness. Overall, we thus show that behavioral performance arises from the integration of task-specific neuronal processes and pre-existing neuronal states describing task-independent behavioral states.


Assuntos
Transtornos Cognitivos , Comportamento Impulsivo , Atenção , Humanos , Comportamento Impulsivo/fisiologia , Neurônios/fisiologia
3.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 39(6): 360-366, nov.-dic. 2020. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-202218

RESUMO

OBJETIVO: Aplicación de la biopsia selectiva de ganglio centinela (BSGC) en el carcinoma de vulva en estadios iniciales y análisis de los resultados, recurrencias y complicaciones. MATERIAL Y MÉTODOS: Se revisaron retrospectivamente 40 pacientes con cáncer de vulva y BSGC entre 2008 y 2018. El día de la intervención se rastrearon las cadenas ganglionares inguinales mediante sonda gammadetectora para identificar los ganglios centinela que se extirparon y remitieron para estudio anatomopatológico intraoperatorio. Posteriormente, se realizó seguimiento a largo plazo con análisis de complicaciones, recaída y mortalidad. RESULTADOS: De las 40 pacientes (edad media: 72 años [47-86]), la tasa de detección global por paciente fue del 95%, con un total de 129 ganglios centinela (GC) (3,22 GC/paciente). En tres de 25 pacientes con lesiones tumorales laterales el drenaje fue bilateral y en dos de 15 con lesiones de línea media fue unilateral. De las 40 linfogammagrafías 16 presentaban drenaje bilateral y 24 unilateral. Se obtuvieron un total de 119 GC- y 10 GC+, realizándose vaciamiento en ocho. En el grupo de GC- se incluyeron un caso de bloqueo linfático y un falso negativo. En 12 de 40 pacientes hubo complicaciones posquirúrgicas, cuatro de ellas linfedemas. Durante una mediana de seguimiento de 40 meses, recayeron seis de 10 con GC+ (40% mortalidad) y siete de 30 GC- (16% mortalidad). CONCLUSIONES: La BSGC en cáncer de vulva es la técnica de elección para una correcta estadificación y tratamiento locorregional. Es importante una adecuada estadificación ganglionar previa a la cirugía para evitar posibles bloqueos linfáticos que puedan inducir falsos negativos


AIM: Application of sentinel lymph node biopsy (SLNB) procedure in early-stage vulvar cancer and analysis of results, recurrences and complications. MATERIAL AND METHODS: 40 patients with vulvar cancer and SLNB between 2008 and 2018 were retrospectively reviewed. During the surgical procedure the inguinofemoral lymph nodes were checked with a gamma probe to identify the sentinel nodes that were removed and referred for intraoperative pathological assessment. Subsequently, long-term patient follow-up was performed with analysis of complications, relapse and mortality. RESULTS: 40 patients (mean age: 72 years [47-86], the overall detection rate per patient was 95% and a total of 129 Sentinel Lymph Nodes (SLNs) were removed (3.22 SLN/patient). In 3 out of 25 patients with lateral tumour lesions drainage was bilateral and in 2 out of 15 with midline lesions drainage was unilateral. On lymphoscintigraphy, 16 out of 40 had bilateral drainage and 24 unilateral. A total of 119 SLN- and 10 SLN+ were obtained, in 8 out of 10 an inguinofemoral lymphadenectomy was performed. In the SLN- group, one case of lymphatic blockage and one false negative were included. In 12 out of 40 patients there were post-surgical complications, 4 of them lymphoedemas. In the median follow-up (40 months), 6 out of 10 with SLN+ (40% mortality) and 7 out of 30 SLN- (16% mortality) had recurrences. CONCLUSIONS: SLNB in vulvar cancer is the technique of choice for correct staging and locoregional therapy. Correct clinical lymph node staging is important before surgery in order to avoid potential blockage drainages which could induce a false negative SLN


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Biópsia de Linfonodo Sentinela , Carcinoma de Células Escamosas/patologia , Neoplasias Vulvares/patologia , Carcinoma de Células Escamosas/mortalidade , Neoplasias Vulvares/mortalidade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Análise de Sobrevida , Seguimentos , Estudos Retrospectivos
4.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32563714

RESUMO

AIM: Application of sentinel lymph node biopsy (SLNB) procedure in early-stage vulvar cancer and analysis of results, recurrences and complications. MATERIAL AND METHODS: 40 patients with vulvar cancer and SLNB between 2008 and 2018 were retrospectively reviewed. During the surgical procedure the inguinofemoral lymph nodes were checked with a gamma probe to identify the sentinel nodes that were removed and referred for intraoperative pathological assessment. Subsequently, long-term patient follow-up was performed with analysis of complications, relapse and mortality. RESULTS: 40 patients (mean age: 72 years [47-86], the overall detection rate per patient was 95% and a total of 129 Sentinel Lymph Nodes (SLNs) were removed (3.22 SLN/patient). In 3 out of 25 patients with lateral tumour lesions drainage was bilateral and in 2 out of 15 with midline lesions drainage was unilateral. On lymphoscintigraphy, 16 out of 40 had bilateral drainage and 24 unilateral. A total of 119 SLN- and 10 SLN+ were obtained, in 8 out of 10 an inguinofemoral lymphadenectomy was performed. In the SLN- group, one case of lymphatic blockage and one false negative were included. In 12 out of 40 patients there were post-surgical complications, 4 of them lymphoedemas. In the median follow-up (40 months), 6 out of 10 with SLN+ (40% mortality) and 7 out of 30 SLN- (16% mortality) had recurrences. CONCLUSIONS: SLNB in vulvar cancer is the technique of choice for correct staging and locoregional therapy. Correct clinical lymph node staging is important before surgery in order to avoid potential blockage drainages which could induce a false negative SLN.


Assuntos
Carcinoma de Células Escamosas/patologia , Metástase Linfática/diagnóstico , Linfocintigrafia/métodos , Biópsia de Linfonodo Sentinela , Neoplasias Vulvares/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Excisão de Linfonodo , Linfedema/etiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Intervalo Livre de Progressão , Estudos Retrospectivos , Neoplasias Vulvares/mortalidade , Neoplasias Vulvares/cirurgia
5.
J Prosthet Dent ; 123(3): 379-383, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31307796

RESUMO

This clinical report describes a chemical abrasive protocol and whitening techniques to quantify modifications to the color and volume produced when eliminating white spots associated with developmental defects in enamel. Chemical (oxidative-erosive) abrasive treatment (whitening + 6.6% hydrochloric acid) resolves white spots up to a depth of 0.2 mm. At greater depths, infiltration with 16% hydrochloric acid followed by composite resin infiltration is recommended.


Assuntos
Cárie Dentária , Clareamento Dental , Resinas Compostas , Esmalte Dentário , Humanos
6.
Brain Imaging Behav ; 10(4): 1289-1307, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26707190

RESUMO

Novel rehabilitation interventions have improved motor recovery by induction of neural plasticity in individuals with stroke. Of these, Music-supported therapy (MST) is based on music training designed to restore motor deficits. Music training requires multimodal processing, involving the integration and co-operation of visual, motor, auditory, affective and cognitive systems. The main objective of this study was to assess, in a group of 20 individuals suffering from chronic stroke, the motor, cognitive, emotional and neuroplastic effects of MST. Using functional magnetic resonance imaging (fMRI) we observed a clear restitution of both activity and connectivity among auditory-motor regions of the affected hemisphere. Importantly, no differences were observed in this functional network in a healthy control group, ruling out possible confounds such as repeated imaging testing. Moreover, this increase in activity and connectivity between auditory and motor regions was accompanied by a functional improvement of the paretic hand. The present results confirm MST as a viable intervention to improve motor function in chronic stroke individuals.


Assuntos
Encéfalo/fisiopatologia , Atividade Motora/fisiologia , Musicoterapia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Percepção Auditiva/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Doença Crônica , Feminino , Mãos/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Plasticidade Neuronal/fisiologia , Testes Neuropsicológicos , Paresia/diagnóstico por imagem , Paresia/etiologia , Paresia/fisiopatologia , Paresia/reabilitação , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/psicologia , Resultado do Tratamento
7.
Neuroscience ; 250: 342-51, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-23876325

RESUMO

The commission of an error triggers cognitive control processes dedicated to error correction and prevention. Post-error adjustments leading to response slowing following an error ("post-error slowing"; PES) might be driven by changes in excitability of the motor regions and the corticospinal tract (CST). The time-course of such excitability modulations of the CST leading to PES is largely unknown. To track these presumed excitability changes after an error, single pulse transcranial magnetic stimulation (TMS) was applied to the motor cortex ipsilateral to the responding hand, while participants were performing an Eriksen flanker task. A robotic arm with a movement compensation system was used to maintain the TMS coil in the correct position during the experiment. Magnetic pulses were delivered over the primary motor cortex ipsilateral to the active hand at different intervals (150, 300, 450 ms) after correct and erroneous responses, and the motor-evoked potentials (MEP) of the first dorsal interosseous muscle (FDI) contralateral to the stimulated hemisphere were recorded. MEP amplitude was increased 450 ms after the error. Two additional experiments showed that this increase was neither associated to the correction of the erroneous responses nor to the characteristics of the motor command. To the extent to which the excitability of the motor cortex ipsi- and contralateral to the response hand are inversely related, these results suggest a decrease in the excitability of the active motor cortex after an erroneous response. This modulation of the activity of the CST serves to prevent further premature and erroneous responses. At a more general level, the study shows the power of the TMS technique for the exploration of the temporal evolution of post-error adjustments within the motor system.


Assuntos
Adaptação Fisiológica/fisiologia , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Magnética Transcraniana , Interpretação Estatística de Dados , Potencial Evocado Motor/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
8.
Int J Obes (Lond) ; 37(9): 1169-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23207406

RESUMO

OBJECTIVE: To assess the influence of supplementation with a moderate dose of vitamin A in early life on adipose tissue development and the response to an obesogenic diet later in life. METHODS: During the suckling period, rat pups received a daily oral dose of retinyl palmitate corresponding to three times the vitamin A ingested daily from maternal milk. Control rats received the vehicle (olive oil). Short-term effects of treatment on gene expression and morphology of white adipose tissue (WAT) were analyzed in animals on the day after weaning (day 21). To study long-term effects, control and vitamin A-treated rats were fed, after weaning, a normal fat or a high-fat (HF) diet for 16 weeks. RESULTS: WAT of vitamin A-treated young rats (day 21) was enriched in small adipocytes with a reduced expression of adipogenic markers (peroxisome proliferator-activated receptor γ and lipoprotein lipase) and an increased cell proliferation potential as indicated by increased expression of proliferating cell nuclear antigen. Increased retinoic acid (RA)-induced transcriptional responses were present in the tissues of vitamin A-treated young rats (day 21) including WAT. Vitamin A-treated rats developed higher adiposity than control rats on a HF diet as indicated by body composition analysis and increased WAT depot mass, adipocyte diameter, WAT DNA content, leptinemia and adipose leptin gene expression. Excess adiposity gain in vitamin A-treated rats developed in the absence of changes in body weight and was attributable to excess adipocyte hyperplasia. No differences in adiposity were observed between vitamin A-treated rats and control rats on a normal fat diet. Total retinol levels in WAT of vitamin A-treated rats were elevated at weaning (day 21) and normalized by day 135 of age. CONCLUSION: Vitamin A intake in the early stages of postnatal life favors subsequent HF diet-induced adiposity gain through mechanisms that may relate to changes in adipose tissue development, likely mediated by RA.


Assuntos
Tecido Adiposo Branco/patologia , Adiposidade , Dieta Hiperlipídica , Vitamina A/análogos & derivados , Vitamina A/farmacologia , Desmame , Tecido Adiposo Branco/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Animais Lactentes/crescimento & desenvolvimento , Peso Corporal , Suplementos Nutricionais , Diterpenos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Masculino , PPAR gama/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Ésteres de Retinil , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos
9.
Minerva Stomatol ; 58(4): 181-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19369923

RESUMO

Hydrogen and carbamide peroxides used for in-office and at-home whitening treatments are potentially harmful to pulp causing various alterations. Also characteristic and quite frequent is the presence of dental sensitivity. The aim of this paper is to review the appearance of post-whitening tooth hypersensitivity in clinical cases treated with different techniques. A study of patients (N = 56) with 5 different dental whitening techniques was managed: in-office light activated, with 35% hydrogen peroxide (N1 = 10); in-office chemical activated, also with 35% hydrogen peroxide (N2 = 10); in-office with custom-formed trays using 35% carbamide peroxide (N3 = 10); at-home with custom-formed trays (N4 = 16, 8 with 10% carbamide peroxide and 8 with 3.5% hydrogen peroxide); and at-home with a 6% carbamide peroxide varnish (N5 = 10). For the set of cases, sensitivity was 55% and varied between slight and intense. All whitening procedures can cause hypersensitivity, although it does not always occur. When present (31-55% of all the patients treated), hypersensitivity is not usually very intense and affects only a few teeth in each patient. Greater sensitivity was observed with in-office chemical activated (70%) and light-activated (100%) whitening techniques. So, after dental whitening treatment, dental hypersensitivity is to be expected, independently of technique and product used, in at least one out of two patients.


Assuntos
Sensibilidade da Dentina/induzido quimicamente , Peróxido de Hidrogênio/efeitos adversos , Oxidantes/efeitos adversos , Peróxidos/efeitos adversos , Clareamento Dental/efeitos adversos , Ureia/análogos & derivados , Peróxido de Carbamida , Combinação de Medicamentos , Humanos , Ureia/efeitos adversos
10.
Enferm. clín. (Ed. impr.) ; 19(2): 83-89, mar.-abr. 2009. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-60259

RESUMO

Objetivo. Realizar una revisión estructurada de la bibliografía entre los años 2000 y 2007, acerca de las necesidades que presentan las personas cuidadoras no profesionalizadas (familiares) de personas supervivientes de accidente cerebro vascular (ACV) en fase subaguda en el ámbito domiciliario. Material y métodos. La búsqueda se realizó en las bases de datos CINAHL, MEDLINE, EMBASE, PSYCHINFO, Cochrane Library Plus, CDSR (coch), DARE, CCTR, ACP Journal Club (ACP), IBECS, LILACS e IME, utilizando los términos ¿cerebral vascular accident¿, ¿caregiver¿ y ¿needs (assesment)¿. Resultadosse seleccionaron un total de 270 resúmenes de artículos, de los que tan sólo 53 cumplieron todos los criterios de inclusión; de éstos, sólo 12 cumplían los niveles de calidad metodológica previamente establecidos. Aunque con mucha variabilidad entre los estudios evaluados, la bibliografía identifica la información y el apoyo en el desarrollo de habilidades en el cuidado, como los 2 ámbitos de necesidades más señalados por las personas cuidadoras no profesionalizadas de familiares supervivientes de ACV. El cuidado de la propia persona cuidadora así como el desarrollo y la provisión de recursos de apoyo al desempeño del rol, son las grandes áreas que estas personas señalan como necesidades en su adaptación al nuevo rol y a la nueva situación. Conclusiones. Los estudios revisados ponen también de manifiesto una incipiente demanda de atención y cuidados para estas cuidadoras. Los muy diferentes contextos de origen de los trabajos revisados, la falta de una definición explícita del concepto de ¿necesidad¿ y la pluralidad de realidades en la figura de la cuidadora dificultan la síntesis de resultados y sugieren el desarrollo de nuevos trabajos en nuestro contexto que traten de tomar en cuenta y superar dichas limitaciones(AU)


Objective. To perform a structured review of the literature from 2000 to 2007 on the needs of the caregivers of stroke survivors in the postacute phase of the illness process at home. MethodsSearches were conducted in the CINAHL, MEDLINE, EMBASE, PSYCHINFO, Cochrane Library Plus, CDSR (coch), DARE, CCTR, ACP Journal Club (ACP), IBECS, LILACS and IME databases using the terms ¿stroke¿, ¿caregiver¿ and ¿needs (assessment)¿. ResultsWe selected 270 abstracts for review. Of these, only 53 met the inclusion criteria and just 12 achieved preestablished quality standards. Despite wide variability among the selected studies, the literature reviewed revealed that the two most prevalent needs for the caregivers of stroke survivors were information and support in the development of caregiving skills. Care for the caregiver herself, as well as the development and provision of support services, were defined as the two main areas where these participants seem to need support while adapting to and performing this newly adopted role. ConclusionsThe studies reviewed show an increasing demand for support and care for stroke survivors¿ caregivers. Because of the highly diverse contexts of these studies, the lack of an explicit definition on the concept of ¿need¿, and the wide heterogeneity in caregivers¿ situations, summarizing the results of these studies is difficult. New studies are required in our context that take these limitations into account and try to overcome them(AU)


Assuntos
Humanos , Cuidadores/psicologia , Acidente Vascular Cerebral/complicações , Avaliação das Necessidades , Assistência Domiciliar/estatística & dados numéricos
11.
Enferm Clin ; 19(2): 83-9, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19285447

RESUMO

OBJECTIVE: To perform a structured review of the literature from 2000 to 2007 on the needs of the caregivers of stroke survivors in the postacute phase of the illness process at home. METHODS: Searches were conducted in the CINAHL, MEDLINE, EMBASE, PSYCHINFO, Cochrane Library Plus, CDSR (coch), DARE, CCTR, ACP Journal Club (ACP), IBECS, LILACS and IME databases using the terms "stroke", "caregiver" and "needs (assessment)". RESULTS: We selected 270 abstracts for review. Of these, only 53 met the inclusion criteria and just 12 achieved preestablished quality standards. Despite wide variability among the selected studies, the literature reviewed revealed that the two most prevalent needs for the caregivers of stroke survivors were information and support in the development of caregiving skills. Care for the caregiver herself, as well as the development and provision of support services, were defined as the two main areas where these participants seem to need support while adapting to and performing this newly adopted role. CONCLUSIONS: The studies reviewed show an increasing demand for support and care for stroke survivors' caregivers. Because of the highly diverse contexts of these studies, the lack of an explicit definition on the concept of "need", and the wide heterogeneity in caregivers' situations, summarizing the results of these studies is difficult. New studies are required in our context that take these limitations into account and try to overcome them.


Assuntos
Cuidadores , Família , Assistência Domiciliar , Acidente Vascular Cerebral/enfermagem , Humanos , Sobreviventes
12.
Int Endod J ; 39(3): 185-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507071

RESUMO

AIM: To evaluate microleakage of a flowable composite used as a protective isolating base, applied with different adhesive systems. METHODOLOGY: Seventy root-filled teeth were divided into seven groups. A flowable composite base (Tetric Flow Chroma) was used with three adhesive techniques (Syntac, Excite, Excite DCS; in the three cases with and without acid etching) and in a control group without dentine conditioning or adhesive placement. A 30% hydrogen peroxide solution was applied for 24 h in the pulp chambers, followed by the placement of a dye (silver nitrate) for 4 h. Each tooth was sectioned longitudinally, and examined under 4x magnification to assess the tooth/restoration dye leakage following a four-degree scale. Percentage of dye penetration was registered. Statistical analysis was made through the Tukey and Mann-Whitney U-tests. RESULTS: Maximum leakage (100% of specimens) was recorded in the control group without an adhesive system. In the groups subjected to acid etching, the percentage of leakage corresponded to Excite DSC (10%), followed by Syntac (20%) and Excite (30%). In the groups in which only an adhesive system was used, 50% of the teeth demonstrated dye leakage. Statistically significant differences in terms of leakage were observed between the control group and the experimental groups (P < 0.05). There were no significant differences among the experimental groups, but comparing the leakage percentages obtained between the groups in which the teeth were subjected to prior acid etching, and those in which no etching was carried out, observed differences were significant (P = 0.04). CONCLUSIONS: There were no significant differences between the adhesive systems in terms of leakage. Acid etching significantly reduced leakage.


Assuntos
Condicionamento Ácido do Dente/métodos , Resinas Compostas/química , Infiltração Dentária , Clareamento Dental/métodos , Análise de Variância , Adaptação Marginal Dentária , Humanos , Estatísticas não Paramétricas , Dente não Vital/terapia
13.
Insect Mol Biol ; 3(2): 117-22, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7987521

RESUMO

Seven EMBL-4 lambda clones containing U1 small nuclear RNA sequences were isolated from a Bombyx mori genomic library. Six of the seven represent unique sequences. The six unique U1 sequences exhibit fixed point 3'-end truncation. Five out of the six clones share immediate 3'-end flanking sequences while two share 5'-end flanking sequences. Fixed point 3'-end truncation and a hierarchy of shared to unique diagnostic mutations may suggest a family of U1 pseudogenes generated from a reverse-transcribed class II pseudogene in B. mori. An ancestral 'master' U1 pseudogene capable of RNA- and/or DNA-mediated transposition may give rise to generations of U1 pseudogenes that include the original pseudogene's flanking sequences. Identical 3'-end truncation in some of these U1 sequences can be explained by RNA self-priming due to intra-strand binding prior to reverse transcription.


Assuntos
Bombyx/genética , Genes de Insetos , Pseudogenes , RNA Nuclear Pequeno/genética , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , Primers do DNA/genética , Biblioteca Genômica , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
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