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1.
Cogn Process ; 23(2): 179-189, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35142948

RESUMO

Interactions among sensory information are important for generating a coherent percept of the external world. Facilitation and inhibition effects in cross-modal perception have been widely studied for decades. The present study tried to confirm the interaction effects between sensory information in a bimodal context and explore these influences when part of the sensory information was presented without participants' subjective awareness. A total of 40 undergraduate participants were recruited in this mixed design study. Participants were required to count the flashing of the black circle (visual task) or the presentation frequency of the beep sound (auditory task) with the presence of either congruent or incongruent sensory signals in the background. Participants in the explicit group generally performed more accurately and also faster with the congruent stimuli than with the incongruent stimuli. Performance accuracy in the visual task in the implicit group was affected by the non-target sound signals which were presented beneath participants' subjective awareness. The better performance yielded in the auditory task than in the visual task was explained by the appropriateness of the auditory stimulation to the task nature. In addition, the supportive findings regarding processing without awareness should be interpreted with caution.


Assuntos
Cognição , Percepção Visual , Estimulação Acústica , Percepção Auditiva/fisiologia , Humanos , Estimulação Luminosa , Tempo de Reação/fisiologia , Percepção Visual/fisiologia
2.
Anim Genet ; 49(1): 36-42, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29194688

RESUMO

Chinese indigenous pigs in Zhejiang Province are well known for their high fecundity. In order to verify breed subdivision at the genomic level, we investigated genetic diversity and population structure of seven breeds and made comparisons with three Western pig breeds using next-generation sequencing data. Parameters obtained from allelic richness and proportion of polymorphic markers indicated that the genetic diversity of the Chinese indigenous pigs was higher than that of the Western pigs, with the highest and lowest values found in the Chaluand and the Landrace pigs respectively. Both neighbor-joining tree and principal components analysis could distinguish breeds from one another and structure analysis showed less differentiation among Western pigs than among the Chinese pigs. The average linkage disequilibrium decay over distance was significantly less in the Chinese pigs compared with the Western pigs, ranging from 188.2 to 280.6 kb for the Chinese pigs and 680.3 to 752.8 kb for the Western breeds and showing an average r2 threshold value of 0.3. Results obtained from high-density SNP comparison over the whole genome on genetic diversity and population structure were in agreement with the current breed classification of the pigs in Zhejiang Province. More importantly, the results presented here advances our current understanding of the genomic biology of Chinese indigenous pigs in Zhejiang Province and allows for implementation of conservation strategies in additional breeds.


Assuntos
Polimorfismo de Nucleotídeo Único , Sus scrofa/genética , Animais , Cruzamento , China , Genética Populacional , Desequilíbrio de Ligação , Análise de Sequência de DNA , Sus scrofa/classificação
3.
Hong Kong Med J ; 24(6): 554-560, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30530869

RESUMO

INTRODUCTION: The aim of the present study was to evaluate the understanding of generic substitution among health care professionals and members of the general public ("general public") in Hong Kong. METHODS: This cross-sectional descriptive study was performed by using a self-completed anonymous questionnaire from March 2015 to May 2017. The questionnaire included demographic data, knowledge of generic drugs, experiences of generic substitution, and views on policy. RESULTS: A total of 2106 general public, 73 doctors, 22 nurses, and 50 pharmacists responded the questionnaire. In all, 41.2% of the general public was aware that generic drugs have the same active ingredients. Although a majority of the health care professionals knew that generic drugs have the same active ingredients (doctors: 79.5%; nurses: 86.4%; pharmacists: 98.0%), many were unaware of bioequivalence (doctors: 37.0%; nurses: 18.2%; pharmacists: 50.0%). "Efficacy" was ranked as the primary concern among all groups; a substantial portion of respondents reported experiencing adverse drug reactions upon generic substitution (general public: 26.6%; doctors: 23.3%; nurses: 9.1%; pharmacists: 42.0%). At least half of the general public, nurses, and pharmacists considered that patients should be given a choice for generic substitution. However, fewer than one-fifth of doctors and nurses and approximately one-third of pharmacists considered that patient consent was needed prior to generic substitution, compared with approximately two-thirds of the general public. CONCLUSION: The knowledge and perception of generic substitution remains low, both in the general public and among health care professionals. This knowledge deficit could potentially lead to different perspectives among stakeholders regarding generic substitution.


Assuntos
Substituição de Medicamentos/psicologia , Medicamentos Genéricos/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Atitude do Pessoal de Saúde , Doença Crônica , Estudos Transversais , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Percepção , Farmacêuticos/estatística & dados numéricos , Médicos/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
4.
Cogn Process ; 19(4): 505-515, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29774479

RESUMO

Emotion can be conceptualized by the dimensional account of emotion with the dimensions of valence and arousal. There is little discussion of the difference in discriminability across the dimensions. The present study hypothesized that any pair of emotional expressions differing in the polarity of both valence and arousal dimensions would be easier to distinguish than a pair differing in only one dimension. The results indicate that the difference in the dimensions did not affect participants' reaction time. Most pairs of emotional expressions, except those involving fear, were similarly discriminative. Reaction times to pairs with a fearful expression were faster than to those without. The fast reaction time to fearful facial expressions underscores the survival value of emotions.


Assuntos
Discriminação Psicológica/fisiologia , Emoções/fisiologia , Expressão Facial , Medo/psicologia , Adolescente , Nível de Alerta/fisiologia , Retroalimentação Fisiológica , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
5.
Int J Psychol ; 52(3): 171-179, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26260767

RESUMO

Detection of angry and happy faces is generally found to be easier and faster than that of faces expressing emotions other than anger or happiness. This can be explained by the threatening account and the feature account. Few empirical studies have explored the interaction between these two accounts which are seemingly, but not necessarily, mutually exclusive. The present studies hypothesised that prominent facial features are important in facilitating the detection process of both angry and happy expressions; yet the detection of happy faces was more facilitated by the prominent features than angry faces. Results confirmed the hypotheses and indicated that participants reacted faster to the emotional expressions with prominent features (in Study 1) and the detection of happy faces was more facilitated by the prominent feature than angry faces (in Study 2). The findings are compatible with evolutionary speculation which suggests that the angry expression is an alarming signal of potential threats to survival. Compared to the angry faces, the happy faces need more salient physical features to obtain a similar level of processing efficiency.


Assuntos
Ira/fisiologia , Emoções/fisiologia , Expressão Facial , Adolescente , Adulto , Feminino , Felicidade , Humanos , Masculino , Adulto Jovem
6.
Clin Genet ; 88(3): 255-60, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25142838

RESUMO

Kabuki or Niikawa-Kuroki syndrome (KS) is a rare disorder with multiple malformations and recurrent infections, especially otitis media. This study aimed to investigate the genetic defects in Kabuki syndrome and determine if immune status is related to recurrent otitis media. Fourteen patients from 12 unrelated families were enrolled in the 9-year study period (2005-2013). All had Kabuki faces, cleft palate, developmental delay, mental retardation, and the short fifth finger. Recurrent otitis media (12/14) and hearing impairment (8/14) were also more common features. Immunologic analysis revealed lower memory CD19+ cells (11/13), lower memory CD4+ cells (8/13), undetectable anti-HBs antibodies (7/13), and antibody deficiency (7/13), including lower IgA (4), IgG (2), and IgG2 (1). Naïve emigrant lymphocytes, lymphocyte proliferation function, complement activity, and superoxide production in polymorphonuclear cells were all normal. All the patients had KMT2D mutations and 10 novel mutations of R1252X, R1757X,Y1998C, P2550R fs2604X, Q4013X, G5379X, E5425K, R5432X, R5432W, and R5500W. Resembling the phenotype of common variable immunodeficiency, KS patients with antibody deficiency, decreased memory cells, and poor vaccine response increased susceptibility to recurrent otitis media. Large-scale prospective studies are warranted to determine if regular immunoglobulin supplementation decreases the frequency of otitis media and severity of hearing impairment.


Assuntos
Anormalidades Múltiplas/genética , Anormalidades Múltiplas/imunologia , Proteínas de Ligação a DNA/genética , Face/anormalidades , Doenças Hematológicas/genética , Doenças Hematológicas/imunologia , Mutação , Proteínas de Neoplasias/genética , Doenças Vestibulares/genética , Doenças Vestibulares/imunologia , Anormalidades Múltiplas/diagnóstico , Análise Mutacional de DNA , Disgamaglobulinemia/genética , Disgamaglobulinemia/imunologia , Feminino , Doenças Hematológicas/diagnóstico , Humanos , Contagem de Linfócitos , Masculino , Fenótipo , Doenças Vestibulares/diagnóstico
7.
Haemophilia ; 21(1): 95-101, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25458735

RESUMO

UNLABELLED: Congenital factor XIII (FXIII) deficiency is a rare condition with substantial risk for life-threatening bleeding. Replacement of deficient FXIII with plasma-derived FXIII concentrate is a treatment option. The current 12-week study evaluated the steady-state pharmacokinetic (PK) and safety profile of prophylactic infusions of FXIII concentrate (human) in patients with congenital FXIII deficiency. Patients received FXIII concentrate (human) 40 IU kg(-1) on Days 0, 28, and 56. FXIII levels were assessed before and after each infusion; steady-state PK parameters were assessed up to 28 days after the infusion on Day 56. Treatment effectiveness in maintaining trough FXIII activity levels ≥ 5% over 28 days and safety parameters were also assessed. Fourteen patients received FXIII concentrate (human) and 13 completed the study. Post-infusion, FXIII activity levels increased to within the range found in patients without congenital FXIII deficiency without reaching supra-therapeutic levels. Non-baseline-adjusted trough FXIII activity levels were maintained at or above 10% at all post-baseline visits in all patients. Steady-state PK parameters were baseline-adjusted; maximum FXIII activity was 87.7% at 1.72 h post-infusion, subsequently declining to a minimum of 5.0%. The half-life was 6.6 days. FXIII concentrate (human) was generally well tolerated. Two patients had possibly treatment-related adverse events. There were no reports of thromboembolism, viral transmission, bleeding events or treatment-related hypersensitivity. These findings support use of FXIII concentrate (human) 40 IU kg(-1) every 28 days as an appropriate regimen for routine, long-term prophylaxis in children and adults with congenital FXIII deficiency. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov/ct2/show/NCT00883090.


Assuntos
Deficiência do Fator XIII/congênito , Fator XIII/farmacocinética , Adolescente , Adulto , Biomarcadores Farmacológicos , Criança , Pré-Escolar , Fator XIII/uso terapêutico , Deficiência do Fator XIII/tratamento farmacológico , Feminino , Humanos , Masculino , Adulto Jovem
8.
J Anim Breed Genet ; 131(2): 116-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24628723

RESUMO

Higher average daily gain, more lean meat yield and less fat yield of porcine carcass increase selling profits for animal producers. Myostatin (MSTN), previously called GDF8, is a member of transforming growth factor-ß (TGF-ß) superfamily. It is a negative regulator for both embryonic development and adult homeostasis of skeletal muscle. In this study, the genotypes of the previously described SNPs MSTN g.435G>A and g.447A>G SNPs in 66 Duroc pigs, 33 Landrace pigs, 180 Duroc × Landrace (DL) pigs and 155 Duroc × Yorkshire × Landrace (DYL) pigs were determined by Taqman SNP Genotyping Assays. For Duroc and Landrace pigs, MSTN g.435GG/g.447AA individual had greater backfat thickness (p < 0.05) than g.435AA/g.447GG individual, whereas MSTN g.435AA/g.447GG had greater meat (p < 0.05) and meat percentage (p < 0.05) than g.435GA/g.447AG individual. For DL and DYL pigs, the MSTN g.435GG/g.447AA animals were greater in backfat at ultrasound 10th rib (p < 0.05) and carcass 10th rib (p < 0.01) than g.435AA/g.447GG individual. The MSTN g.435AA/g.447GG individual also had higher values than g.435GG/g.447AA for anterior-end meat (p < 0.05), posterior-end meat (p < 0.01), total meat weight (p < 0.01) and meat percentage (p < 0.01). This study confirmed evidence that MSTN g.435G>A and g.447A>G affected carcass traits in pigs. The effects of the mutated alleles were additive with the maximal effects resulting from two copies of the mutated allele. Selection for MSTN g.435A/g.447G allele is expected to increase muscle of limb and total meat production and decrease backfat thickness.


Assuntos
Miostatina/genética , Fenótipo , Regiões Promotoras Genéticas/genética , Suínos/anatomia & histologia , Suínos/genética , Animais , Técnicas de Genotipagem , Polimorfismo de Nucleotídeo Único , Especificidade da Espécie
9.
Ergonomics ; 57(10): 1549-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25017144

RESUMO

The ISO 2631-1 ( 1997 ) provides methodologies for assessment of the seated human body comfort in response to vibrations. The standard covers various conditions such as frequency content, direction and location of the transmission of the vibration to the human body. However, the effects of seat structural dynamics mode shapes and corresponding resonances have not been discussed. This study provides important knowledge about the effects of vehicle seat structural vibration modes on discomfort assessment. The occupied seat resonant frequencies and corresponding vibration modes were measured and comfort test was carried out based on the paired comparison test method. The results show that the ISO 2631-1 ( 1997 ) method significantly underestimates the vibration discomfort level around the occupied seat twisting resonant frequencies. This underestimation is mainly due to the ISO suggested location of the accelerometer pad on the seatback. The centre of the seatback is a nodal point at the seat twisting mode. Therefore, it underestimates the total vibration transferred to the occupant body from the seatback. PRACTITIONER SUMMARY: The effects of the vehicle seat structural dynamics have not been discussed in the human body vibration ISO . The results of this research show that the current measurement method suggested by ISO 2631-1 (1997) can significantly underestimate the vibration discomfort level at around the seat structural vibration mode.


Assuntos
Automóveis , Acelerometria , Adulto , Automóveis/normas , Desenho de Equipamento , Humanos , Masculino , Vibração/efeitos adversos , Adulto Jovem
10.
PLoS One ; 18(1): e0272716, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36608021

RESUMO

The Coronavirus Disease 2019 (COVID-19) pandemic renewed interest in infectious aerosols and reducing risk of airborne respiratory pathogen transmission, prompting development of devices to protect healthcare workers during airway procedures. However, there are no standard methods for assessing the efficacy of particle containment with these protective devices. We designed and built an aerosol bio-containment device (ABCD) to contain and remove aerosol via an external suction system and tested the aerosol containment of the device in an environmental chamber using a novel, quantitative assessment method. The ABCD exhibited a strong ability to control aerosol exposure in experimental and computational fluid dynamic (CFD) simulated scenarios with appropriate suction use and maintenance of device seals. Using a log-risk-reduction framework, we assessed device containment efficacy and showed that, when combined with other protective equipment, the ABCD can significantly reduce airborne clinical exposure. We propose this type of quantitative analysis serves as a basis for rating efficacy of aerosol protective enclosures.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Aerossóis e Gotículas Respiratórios , Equipamento de Proteção Individual , Equipamentos de Proteção , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle
11.
Br J Cancer ; 107(7): 1125-30, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-22929889

RESUMO

BACKGROUND: Tissue factor (TF), which has a role in normal tissue haemostasis, was reported to be aberrantly expressed, associated with higher microvascular density and a poor prognosis in intestinal-type gastric adenocarcinoma in the Japanese population. This is the first study to look at the relationship of TF and the metaplasia-adenoma-carcinoma sequence (MACS) of gastric cancer in a European population. METHODS: The expression of TF was examined immunohistochemically in 191 gastric tissue samples: (13: normal; 18: intestinal metaplasia; 160: gastric adenocarcinoma) from the European population. RESULTS: TF was not expressed in normal gastric mucosal cells. A strong intensity of staining was found in intestinal metaplasia cells but in 2 of 18 samples. TF expression increased with advancing stage of gastric cancer (P<0.0001, Jonckheere's test for ordered medians). Stage 3-4 gastric cancers preferentially expressed TF (34%, P=0.04). In comparison with the Japanese study, TF was not expressed at a higher level in intestinal vs diffuse-type gastric cancers and expression had 'no prognostic' significance. CONCLUSION: TF may be involved in tumour progression along the MACS of gastric cancer in the European population and is shown to start in precancerous lesions. However, clinical features may differ due to differences in biological features in the two populations, as reflected by differences in TF expression profile.


Assuntos
Adenoma/metabolismo , Carcinoma/metabolismo , Neoplasias Gástricas/metabolismo , Estômago/patologia , Tromboplastina/biossíntese , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenoma/genética , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/genética , Carcinoma/patologia , Progressão da Doença , Feminino , Mucosa Gástrica/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Tromboplastina/genética , Tromboplastina/metabolismo , População Branca
12.
Int J Oral Maxillofac Surg ; 50(6): 763-773, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33218918

RESUMO

The aim of this study was to compare the outcomes of surgical-orthodontic treatment between hemifacial microsomia (HFM) patients who had and had not undergone early mandibular distraction osteogenesis (DO). Twenty adult unilateral HFM patients were included, seven who had undergone early mandibular DO (DO group) and 13 who had not (NDO group). All patients were type IIB, except for one type IIA patient in the NDO group. Mean age at definitive surgery was 20.72±2.96 years. Linear, cross-sectional, and volumetric measurements were obtained from serial cone beam computed tomography scans. Data were obtained pre-surgery (T0), 1 week after surgery (T1), and at treatment completion (T2) to determine surgical movement, post-surgical stability, and net gain movement. Surgical and ultimate outcomes did not differ significantly between the groups. The overall surgical movement among all patients was as follows (mean values): maxillomandibular complex (MMC) symmetry was achieved by Le Fort I differential roll movement (3.78mm extrusion on the affected side, 4.28mm impaction on the non-affected side), a combination of medial movement and yaw rotation of MMC, and genioplasty. Upper and lower dental midlines and deviated menton were shifted by 5.73mm, 5.08mm, and 12.38mm, respectively. Anterior impaction and advancement with counterclockwise rotation of MMC were also performed. Menton was advanced by 6.14mm and lower facial height was increased by 3.55mm. Neither group exhibited a significant difference in stability. Relapse at the maxilla was <1mm and relapse at the mandible was <1.5mm. The results suggest that early DO had limited beneficial effects on the definitive correction outcome. HFM patients achieved acceptable symmetry and a stable surgical outcome, regardless of early DO, following surgical-orthodontic correction at skeletal maturity with three-dimensional surgical simulation.


Assuntos
Síndrome de Goldenhar , Osteogênese por Distração , Adulto , Estudos Transversais , Assimetria Facial/diagnóstico por imagem , Assimetria Facial/cirurgia , Síndrome de Goldenhar/diagnóstico por imagem , Síndrome de Goldenhar/cirurgia , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Resultado do Tratamento
13.
Anim Genet ; 41(2): 208-12, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19793264

RESUMO

Microsatellites are the most popular markers for parentage assignment and population genetic studies. To meet the demand for international comparability for genetic studies of Asian seabass, a standard panel of 28 microsatellites has been selected and characterized using the DNA of 24 individuals from Thailand, Malaysia, Indonesia and Australia. The average allele number of these markers was 10.82 +/- 0.71 (range: 6-19), and the expected heterozygosity averaged 0.76 +/- 0.02 (range: 0.63-1.00). All microsatellites showed Mendelian inheritance. In addition, eight standard size controls have been developed by cloning a set of microsatellite alleles into a pGEM-T vector to calibrate allele sizes determined by different laboratories, and are available upon request. Seven multiplex PCRs, each amplifying 3-5 markers, were optimized to accurately and rapidly genotype microsatellites. Parentage assignment using 10 microsatellites in two crosses (10 x 10 and 20 x 20) demonstrated a high power of these markers for revealing parent-sibling connections. This standard set of microsatellites will standardize genetic diversity studies of Asian seabass, and the multiplex PCR sets will facilitate parentage assignment.


Assuntos
Bass/genética , Repetições de Microssatélites , Animais , Sudeste Asiático , Austrália , Variação Genética , Genética Populacional
14.
Int Forum Allergy Rhinol ; 10(10): 1173-1179, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32652898

RESUMO

The coronavirus disease-2019 (COVID-19) pandemic has heightened the awareness of aerosol generation by human expiratory events and their potential role in viral respiratory disease transmission. Concerns over high severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) viral burden of mucosal surfaces has raised questions about the aerosol-generating potential and dangers of many otorhinolaryngologic procedures. However, the risks of aerosol generation and associated viral transmission by droplet or airborne routes for many otorhinolaryngology procedures are largely unknown. Indoor aerosol and droplet viral respiratory transmission risk is influenced by 4 factors: (1) aerosol or droplet properties; (2) indoor airflow; (3) virus-specific factors; and (4) host-specific factors. Herein we elaborate on known aerosol vs droplet properties, indoor airflow, and aerosol-generating events to provide context for risks of aerosol infectious transmission. We also provide simple but typically effective measures for mitigating the spread and inhalation of viral aerosols in indoor settings. Understanding principles of infectious transmission, aerosol and droplet generation, as well as concepts of indoor airflow, will assist in the integration of new data on SARS-CoV-2 transmission and activities that can generate aerosol to best inform on the need for escalation or de-escalation from current societal and institutional guidelines for protection during aerosol-generating procedures.


Assuntos
Aerossóis , COVID-19/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Otolaringologia/métodos , SARS-CoV-2/fisiologia , Poluição do Ar em Ambientes Fechados , COVID-19/prevenção & controle , Humanos , Inalação , Gotículas Lipídicas , Pandemias
15.
Science ; 275(5302): 945-8, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9020070

RESUMO

For the past decade the immune system has been exploited as a rich source of de novo catalysts. Catalytic antibodies have been shown to have chemoselectivity, enantioselectivity, large rate accelerations, and even an ability to reroute chemical reactions. In many instances catalysts have been made for reactions for which there are no known natural or man-made enzymes. Yet, the full power of this combinatorial system can only be exploited if there was a system that allows for the direct selection of a particular function. A method that allows for the direct chemical selection for catalysis from antibody libraries was so devised, whereby the positive aspects of hybridoma technology were preserved and re-formatted in the filamentous phage system to allow direct selection of catalysis. This methodology is based on a purely chemical selection process, making it more general than biologically based selection systems because it is not limited to reaction products that perturb cellular machinery.


Assuntos
Anticorpos Catalíticos , Biblioteca de Peptídeos , Animais , Anticorpos Catalíticos/genética , Anticorpos Catalíticos/metabolismo , Catálise , Clonagem Molecular , Colífagos , Ditiotreitol , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Galactosídeos/metabolismo , Haptenos , Hibridomas , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Indóis/metabolismo , Isopropiltiogalactosídeo/metabolismo , Camundongos , Nitrofenilgalactosídeos/metabolismo , Reação em Cadeia da Polimerase , Soroalbumina Bovina , Transformação Bacteriana , beta-Galactosidase/metabolismo
16.
Neuron ; 15(3): 527-39, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7546733

RESUMO

c-RET is an orphan receptor tyrosine kinase essential for enteric neurogenesis in mice and is involved in several human genetic disorders. RET is also one of the earliest surface markers expressed by postmigratory neural crest cells in the gut. We generated anti-RET monoclonal antibodies to isolate such cells. We find that RET+ cells are antigenically and functionally distinct from neural crest stem cells (NCSCs) characterized previously. Unlike NCSCs, which are RET- and MASH1-, most RET+ cells express MASH1. Moreover, unlike NCSCs, which are multipotent and have high proliferative capacity, many RET+ cells generate only neurons following a limited number of divisions. This behavior is observed even in the presence of glial growth factor, a polypeptide that suppresses neuronal and promotes glial differentiation by NCSCs. These data provide direct evidence for the existence of committed neuronal progenitor cells and support a model of neural crest lineage diversification by progressive restriction of developmental potential.


Assuntos
Divisão Celular , Proteínas de Drosophila , Crista Neural/citologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Diferenciação Celular , Movimento Celular , Cricetinae , Fibronectinas/farmacologia , Fator de Maturação da Glia , Glicoproteínas/farmacologia , Imunofenotipagem , Proteínas do Tecido Nervoso/farmacologia , Crista Neural/imunologia , Neurregulinas , Neurônios/química , Neurônios/metabolismo , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-ret , Ratos , Receptores Proteína Tirosina Quinases/análise , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Proteínas Recombinantes/farmacologia
17.
Neuron ; 22(4): 693-705, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10230790

RESUMO

We have investigated the specification of noradrenergic neurotransmitter identity in neural crest stem cells (NCSCs). Retroviral expression of both wild-type and dominant-negative forms of the paired homeodomain transcription factor Phox2a indicates a crucial and direct role for this protein (and/or the closely related Phox2b) in the regulation of endogenous tyrosine hydroxylase (TH) and dopamine-beta hydroxylase (DBH) gene expression in these cells. In collaboration with cAMP, Phox2a can induce expression of TH but not of DBH or of panneuronal genes. Phox2 proteins are, moreover, necessary for the induction of both TH and DBH by bone morphogenetic protein 2 (BMP2) (which induces Phox2a/b) and forskolin. They are also necessary for neuronal differentiation. These data suggest that Phox2a/b coordinates the specification of neurotransmitter identity and neuronal fate by cooperating environmental signals in sympathetic neuroblasts.


Assuntos
Proteínas de Homeodomínio/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Crista Neural/fisiologia , Neurotransmissores/fisiologia , Células-Tronco/fisiologia , Fatores de Transcrição/fisiologia , Glândulas Suprarrenais/fisiologia , Animais , Colforsina/farmacologia , Dopamina beta-Hidroxilase/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Genes Dominantes , Crista Neural/citologia , Crista Neural/efeitos dos fármacos , Ratos , Sistema Nervoso Simpático/fisiologia , Tirosina 3-Mono-Oxigenase/genética
18.
Neuron ; 1(6): 463-76, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3272176

RESUMO

We have characterized and sequenced cDNA clones corresponding to the neural-specific SCG10 mRNA. The predicted amino acid sequence is novel and not strongly homologous to that of any known polypeptide. The protein is encoded by two mRNAs that differ in their choice of polyadenylation site. Immunocytochemical localization experiments using an affinity-purified antibody (against an SCG10-TrpE fusion protein) reveal accumulations of punctate staining in the perinuclear cytoplasm, axons, and growth cones of cultured neurons. SCG10 levels are maximal in the embryonic CNS but are dramatically reduced in the adult. Preliminary cell fractionation experiments suggest that the protein is tightly associated with membranes but is not itself an integral membrane protein. The apparent localization and timing of expression of the SCG10 protein are reminiscent of GAP-43, but the sequences of the two polypeptides are unrelated. Cross-hybridizing mRNAs and antigenically related proteins are found in several nonneuronal cell lines that do not express SCG10.


Assuntos
Encéfalo/metabolismo , Gânglios Simpáticos/metabolismo , Proteínas de Membrana/genética , Fatores de Crescimento Neural/farmacologia , Neurônios/metabolismo , RNA Mensageiro/genética , Envelhecimento , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sequência de Bases , Encéfalo/crescimento & desenvolvimento , Proteínas de Transporte , Células Cultivadas , DNA/genética , Biblioteca Gênica , Proteínas dos Microtúbulos , Dados de Sequência Molecular , Neurônios/citologia , Biossíntese de Proteínas , Conformação Proteica , RNA Mensageiro/efeitos dos fármacos , Ratos , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
19.
Anim Genet ; 39(1): 34-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18076743

RESUMO

Quantitative trait loci (QTL) affecting growth traits have previously been mapped in linkage groups (LG) 2, 3 and 23 of Barramundi (Lates carcalifer), but these QTL have not been verified in different genetic backgrounds and environments. Here, we report the identification and verification of QTL for growth traits on LG2, 3, 10 and 23 in F(1) families constructed using brooders from the Singapore Marine Aquaculture Center (MAC) and from wild stocks collected in Thailand (THAI). The previously detected QTL for body weight and length linked to marker Lca371 on LG2 were confirmed in both the MAC and THAI families, whereas other QTL previously mapped to LG3 and 23 were only detected in one of the two families. QTL for body weight and length were identified in the MAC family, but not in the THAI family, in a region where the insulin-like growth factor 2 (IGF2) and tyrosine hydroxylase 1 (TH1) genes are located on LG10. Significant epistatic interactions were identified between markers Lca287 on LG2 and IGF2 on LG10 for growth trait QTL in the MAC family, but not in the THAI family. Effects of the IGF2, TH1 and parvalbumin 1 candidate genes were family-specific. Our results indicate that some but not all QTL are family-specific in Barramundi.


Assuntos
Perciformes/crescimento & desenvolvimento , Perciformes/genética , Locos de Características Quantitativas , Alelos , Animais , Animais Selvagens/genética , Animais Selvagens/crescimento & desenvolvimento , Cruzamento , Mapeamento Cromossômico , DNA/genética , Epistasia Genética , Feminino , Pesqueiros , Variação Genética , Fator de Crescimento Insulin-Like II/genética , Masculino , Repetições de Microssatélites , Parvalbuminas/genética , Perciformes/classificação , Fenótipo , Singapura , Especificidade da Espécie , Tailândia , Tirosina 3-Mono-Oxigenase/genética
20.
Curr Biol ; 7(6): 440-50, 1997 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9197246

RESUMO

BACKGROUND: The interplay between growth factors and transcription factors in vertebrate neurogenesis is poorly understood. MASH1 is a basic helix-loop-helix (bHLH) transcription factor that is essential for autonomic neurogenesis. Bone morphogenetic protein (BMP) 2, and its relative BMP4, have been shown to induce expression of MASH1 and to promote autonomic neuronal differentiation in neural crest stem cells. The relationship between expression of MASH1 and the neurogenic competence of neural crest cells has not been investigated, however. RESULTS: We have examined the function of MASH1 in neurogenic competence using a population of immuno-isolated neural-crest-derived progenitor cells. Post-migratory neural crest cells isolated from fetal rat gut expressed Mash1, yet comprised a mixture of committed neuronal precursors and non-neuronal cells. The non-neuronal cells remained competent to differentiate to neurons, however, if challenged with BMP2. Such competence declines with time and is paralleled by a decline in Mash1 expression in the cells. Expression of endogenous Mash1 can be maintained by BMP2; in turn, constitutive expression of Mash1 from a retroviral vector maintains competence for neuronal differentiation in response to late addition of BMP2. CONCLUSIONS: These data suggest that MASH1 promotes competence for neurogenesis, in a manner similar to its homologs, the proneural genes achaete-scute in Drosophila. They also reveal an unexpected feedback interaction between BMP2 and MASH1 during neuronal differentiation. MASH1 may play multiple roles at successive stages of development within a neurogenic lineage, only one of which is revealed by a loss-of-function mutation.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila , Sequências Hélice-Alça-Hélice , Tecido Nervoso/embriologia , Crista Neural/embriologia , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Proteína Morfogenética Óssea 2 , Diferenciação Celular , Movimento Celular , Células Clonais , Proteínas de Ligação a DNA/genética , Sistema Digestório/citologia , Sistema Digestório/embriologia , Relação Dose-Resposta a Droga , Músculo Liso/embriologia , Tecido Nervoso/citologia , Tecido Nervoso/efeitos dos fármacos , Crista Neural/citologia , Crista Neural/efeitos dos fármacos , Neuroglia/citologia , Neurônios/citologia , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-ret , Ratos , Receptores Proteína Tirosina Quinases/isolamento & purificação , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/genética
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