Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 142
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Anim Genet ; 52(5): 759-761, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34339052

RESUMO

Gene doping is prohibited in horseracing. In a previous study, we developed a method for non-targeted transgene detection using DELLY, which is based on split-read (SR) and paired-end (PE) algorithms to detect structural variants, on WGS data. In this study, we validated the detection sensitivity of DELLY using artificially generated sequence data of 12 target genes. With DELLY, at least one intron was detected as a deletion in eight targeted genes using the 150 bp PE read WGS data, whereas all targeted genes were detected by DELLY using the 100 bp PE read data. The detection sensitivity was higher in 100 bp PE reads than in 150 bp PE reads, despite a lower total sequence coverage, probably because of mismatch tolerance between the mapped reads and reference genome. In addition, it was observed that the average intron size detected by SR alone was 293 bp and that that detected by both SR and PE was 8924 bp. Thus, we showed that transgenes with various intron-exon structures could be detected using DELLY, suggesting its application in gene-doping control in horses.


Assuntos
Animais Geneticamente Modificados , Dopagem Esportivo , Cavalos/genética , Íntrons , Esportes , Transgenes , Algoritmos , Animais , Éxons
2.
Anim Genet ; 51(1): 43-50, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31612520

RESUMO

Fractures are medical conditions that compromise the athletic potential of horses and/or the safety of jockeys. Therefore, the reduction of fracture risk is an important horse and human welfare issue. The present study used molecular genetic approaches to determine the effect of genetic risk for fracture at four candidate SNPs spanning the myostatin (MSTN) gene on horse chromosome 18. Among the 3706 Japanese Thoroughbred racehorses, 1089 (29.4%) had experienced fractures in their athletic life, indicating the common occurrence of this injury in Thoroughbreds. In the case/control association study, fractures of the carpus (carpal bones and distal radius) were statistically associated with g.65809482T/C (P = 1.17 x 10-8 ), g.65868604G/T (P = 2.66 x 10-9 ), and g.66493737C/T (P = 6.41 x 10-8 ). In the retrospective cohort study using 1710 racehorses born in 2000, the relative risk (RR) was highest for male horses at g.65868604G/T, based on the dominant allele risk model (RR = 2.251, 95% confidence interval 1.407-3.604, P = 0.00041), and for female horses at g.65868604G/T, based on the recessive allele risk model (RR = 2.313, 95% confidence interval 1.380-3.877, P = 0.00163). Considering the association of these SNPs with racing performance traits such as speed, these genotypes may affect the occurrence of carpus fractures in Japanese Thoroughbred racehorses as a consequence of the non-genetic influence of the genotype on the distance and/or intensity of racing and training. The genetic information presented here may contribute to the development of strategic training programs and racing plans for racehorses that improve their health and welfare.


Assuntos
Fraturas Ósseas/genética , Fraturas Ósseas/veterinária , Cavalos/genética , Polimorfismo de Nucleotídeo Único , Animais , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Japão , Masculino , Estudos Retrospectivos
3.
BMC Pulm Med ; 20(1): 84, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252718

RESUMO

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is characterized by the accumulation of surfactant proteins within the alveolar spaces. Autoimmune PAP (APAP) caused by elevated levels of GM-CSF autoantibodies (GM-Ab) is very rarely associated with systemic autoimmune disease. Here we report a case of APAP manifested during immunosuppressive treatment for polymyositis with interstitial lung disease. CASE PRESENTATION: A 52-year-old woman treated at our hospital because of polymyositis with interstitial pneumonia had maintained remission by immunosuppressive treatment for 15 years. She had progressive dyspnea subsequently over several months with her chest CT showing ground-glass opacities (GGO) in bilateral geographic distribution. Her bronchoalveolar lavage fluid with cloudy appearance revealed medium-sized foamy macrophages and PAS-positive amorphous eosinophilic materials by cytological examination. We diagnosed her as APAP due to an increased serum GM-CSF autoantibody level. Attenuating immunosuppression failed to lead GGO improvement, but whole lung lavage (WLL) was effective in her condition. CONCLUSIONS: PAP should be considered as one of the differential diseases when the newly interstitial shadow was observed during immunosuppressive treatment. WLL should be regarded as the treatment option for APAP concurred in connective tissue disease (CTD).


Assuntos
Autoanticorpos/sangue , Doenças Autoimunes/diagnóstico , Doenças Pulmonares Intersticiais/complicações , Polimiosite/complicações , Proteinose Alveolar Pulmonar/diagnóstico , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Líquido da Lavagem Broncoalveolar/citologia , Dispneia/etiologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Imunossupressores/efeitos adversos , Pulmão/fisiopatologia , Doenças Pulmonares Intersticiais/tratamento farmacológico , Pessoa de Meia-Idade , Polimiosite/tratamento farmacológico , Proteinose Alveolar Pulmonar/imunologia , Proteinose Alveolar Pulmonar/fisiopatologia , Proteinose Alveolar Pulmonar/terapia , Tomografia Computadorizada por Raios X
4.
Allergy ; 73(7): 1436-1446, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29350763

RESUMO

BACKGROUND: Companion animals are also affected by IgE-mediated allergies, but the eliciting molecules are largely unknown. We aimed at refining an allergen microarray to explore sensitization in horses and compare it to the human IgE reactivity profiles. METHODS: Custom-designed allergen microarray was produced on the basis of the ImmunoCAP ISAC technology containing 131 allergens. Sera from 51 horses derived from Europe or Japan were tested for specific IgE reactivity. The included horse patients were diagnosed for eczema due to insect bite hypersensitivity, chronic coughing, recurrent airway obstruction and urticaria or were clinically asymptomatic. RESULTS: Horses showed individual IgE-binding patterns irrespective of their health status, indicating sensitization. In contrast to European and Japanese human sensitization patterns, frequently recognized allergens were Aln g 1 from alder and Cyn d 1 from Bermuda grass, likely due to specific respiratory exposure around paddocks and near the ground. The most prevalent allergen for 72.5% of the tested horses (37/51) was the 2S-albumin Fag e 2 from buckwheat, which recently gained importance not only in human but also in horse diet. CONCLUSION: In line with the One Health concept, covering human health, animal health and environmental health, allergen microarrays provide novel information on the allergen sensitization patterns of the companion animals around us, which may form a basis for allergen-specific preventive and therapeutic concepts.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , Fagopyrum/efeitos adversos , Animais , Mapeamento de Epitopos/métodos , Epitopos/genética , Feminino , Cavalos , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino
5.
Diabet Med ; 33(8): 1118-24, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26173591

RESUMO

AIMS: To examine if a simple biomarker can identify people with diabetes who are at high risk of atrial fibrillation. METHODS: A retrospective cohort study was conducted at a single centre in people with Type 2 diabetes referred to our department between January 2000 and December 2007. In 517 consecutive people without any history, signs or symptoms of atrial fibrillation at baseline, the association between baseline B-type natriuretic peptide level and future atrial fibrillation incidence was examined, with adjustments for other potentially confounding factors. RESULTS: A total of 28 people were diagnosed with new-onset atrial fibrillation during a median 6-year follow-up. When people were categorized into three groups according to B-type natriuretic peptide clinical thresholds (20 and 100 pg/ml), hazard ratios for the development of atrial fibrillation in the middle and highest B-type natriuretic peptide groups were 2.8 and 9.4, respectively, compared with the lowest B-type natriuretic peptide group. Time-dependent receiver-operating curve analysis identified a threshold for B-type natriuretic peptide to detect atrial fibrillation development of 52.8 pg/ml (sensitivity 75.2%, specificity 68.8%). The B-type natriuretic peptide predictive value was independent of and similar to that of left atrial size and ventricular dimension. CONCLUSION: In people with Type 2 diabetes, high baseline B-type natriuretic peptide levels were significantly associated with future atrial fibrillation development.


Assuntos
Fibrilação Atrial/sangue , Diabetes Mellitus Tipo 2/sangue , Peptídeo Natriurético Encefálico/sangue , Idoso , Fibrilação Atrial/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos
6.
J Vet Pharmacol Ther ; 39(3): 264-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26538319

RESUMO

Procaterol (PCR) is a beta-2-adrenergic bronchodilator widely used in Japanese racehorses for treating lower respiratory disease. The pharmacokinetics of PCR following single intravenous (0.5 µg/kg) and oral (2.0 µg/kg) administrations were investigated in six thoroughbred horses. Plasma and urine concentrations of PCR were measured using liquid chromatography-mass spectrometry. Plasma PCR concentration following intravenous administration showed a biphasic elimination pattern. The systemic clearance was 0.47 ± 0.16 L/h/kg, the steady-state volume of the distribution was 1.21 ± 0.23 L/kg, and the elimination half-life was 2.85 ± 1.35 h. Heart rate rapidly increased after intravenous administration and gradually decreased thereafter. A strong correlation between heart rate and plasma concentration of PCR was observed. Plasma concentrations of PCR after oral administration were not quantifiable in all horses. Urine concentrations of PCR following intravenous and oral administrations were quantified in all horses until 32 h after administration. Urine PCR concentrations were not significantly different on and after 24 h between intravenous and oral administrations. These results suggest that the bioavailability of orally administrated PCR in horses is very poor, and the drug was eliminated from the body slowly based on urinary concentrations. This report is the first study to demonstrate the pharmacokinetic character of PCR in thoroughbred horses.


Assuntos
Broncodilatadores/farmacocinética , Cavalos/sangue , Procaterol/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Broncodilatadores/sangue , Broncodilatadores/urina , Feminino , Meia-Vida , Frequência Cardíaca/efeitos dos fármacos , Injeções Intravenosas/veterinária , Masculino , Procaterol/sangue , Procaterol/urina
7.
Am J Transplant ; 13(12): 3278-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24165284

RESUMO

Diffuse pulmonary arteriovenous malformations (AVMs) are associated with a poor prognosis and the therapeutic strategy remains controversial. We describe a pediatric patient with diffuse pulmonary AVMs associated with hereditary hemorrhagic telangiectasia (HHT), who presented with two cerebral AVMs in the parietal and occipital lobes as well. Of note, successful bilateral lung transplantation not only improved the hypoxemia but also resulted in size reduction of the cerebral AVMs. Although it is essential to consider involvements other than pulmonary AVMs, especially brain AVMs, to decide the indication, lung transplantation can be a viable therapeutic option for patients with diffuse pulmonary AVMs and HHT.


Assuntos
Malformações Arteriovenosas/complicações , Pneumopatias/complicações , Transplante de Pulmão , Adolescente , Malformações Arteriovenosas/terapia , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/complicações , Ataque Isquêmico Transitório/complicações , Pneumopatias/terapia , Telangiectasia Hemorrágica Hereditária/complicações , Telangiectasia Hemorrágica Hereditária/terapia , Resultado do Tratamento
8.
Equine Vet J ; 43(3): 324-31, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21492210

RESUMO

REASONS FOR PERFORMING STUDY: To improve the understanding of exercise related sudden death in Thoroughbred racehorses. OBJECTIVES: To describe the post mortem findings in cases of sudden death associated with exercise in 268 Thoroughbred racehorses. METHODS: Gross and histological post mortem findings of 268 cases of sudden death were collated and reviewed. Cases originated from 6 racing jurisdictions around the world. Sudden death was defined as acute collapse and death in a closely observed and previously apparently healthy Thoroughbred racehorse, during, or within one hour after, exercise. Cause of death as determined by the attending pathologist was categorised as definitive, presumptive or unexplained and compared between the different populations. Cardiopulmonary lesions recorded at post mortem examination were compared between different populations. RESULTS: Pathologists recorded a definitive cause of death in 53% (143/268) of cases. Major definitive causes of sudden death included cardiac failure, apparent pulmonary failure, pulmonary haemorrhage, haemorrhage associated with pelvic fractures or with idiopathic blood vessel rupture, and spinal cord injury. A presumptive cause of death was made in 25% (67/268) of cases and death remained unexplained in 22% (58/268) of cases. There were several statistically significant inter-population differences in the cause of death and in reporting of cardiopulmonary lesions. CONCLUSIONS: Sudden death can be attributed to a variety of causes. Causes of sudden death and the lesions found in cases of exercise-related sudden death are similar in different racing jurisdictions. However, the lesions are often not specific for the cause of death and determination of the cause of death is therefore affected by interpretation by the individual pathologist.


Assuntos
Morte Súbita/veterinária , Doenças dos Cavalos/etiologia , Cavalos , Condicionamento Físico Animal , Animais , Sistema Nervoso Central/lesões , Morte Súbita/etiologia , Feminino , Cardiopatias/complicações , Cardiopatias/veterinária , Pneumopatias/complicações , Pneumopatias/veterinária , Masculino , Choque Hemorrágico/complicações , Choque Hemorrágico/veterinária
9.
Science ; 267(5199): 897-9, 1995 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-7846533

RESUMO

Plasmids carrying gene pairs encoding type II DNA restriction endonucleases and their cognate modification enzymes were shown to have increased stability in Escherichia coli. The descendants of cells that had lost these genes appeared unable to modify a sufficient number of recognition sites in their chromosomes to protect them from lethal attack by the remaining restriction enzyme molecules. The capacity of these genes to act as a selfish symbiont is likely to have contributed to the evolution of restriction-modification gene pairs.


Assuntos
Enzimas de Restrição-Modificação do DNA/genética , Escherichia coli/genética , Plasmídeos , Apoptose , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/metabolismo , Enzimas de Restrição-Modificação do DNA/metabolismo , DNA Bacteriano/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Escherichia coli/citologia , Escherichia coli/enzimologia , Genes Bacterianos , Transformação Bacteriana
10.
Science ; 155(3767): 1257-9, 1967 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-6018645

RESUMO

Tetraethylammonium ions were injected into the presynaptic axon of the squid giant synapse. Injection of these ions caused prolongation of the action potential with decreased out ward current. The prolonged spike was associated with increased release and prolonged activity of the transmitter substance. Although the amplitude of the postsynaptic potential increased with presynaptic depolarization, strong depolarization blocked transmitter re lease. In the injected presynaptic axon, transmitter release was blocked by 10(-6) gram of tetrodotoxin per milliliter. Transmitter release appears to be under control of presynaptic potential levels.


Assuntos
Axônios/efeitos dos fármacos , Sinapses/fisiologia , Compostos de Tetraetilamônio/farmacologia , Toxinas Biológicas/farmacologia , Animais , Transporte Biológico , Eletrofisiologia , Moluscos , Potássio , Sódio , Tetrodotoxina/farmacologia
11.
Science ; 291(5513): 2600-2, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11283371

RESUMO

The Drosophila Dmblm locus is a homolog of the human Bloom syndrome gene, which encodes a helicase of the RECQ family. We show that Dmblm is identical to mus309, a locus originally identified in a mutagen-sensitivity screen. One mus309 allele, which carries a stop codon between two of the helicase motifs, causes partial male sterility and complete female sterility. Mutant males produce an excess of XY sperm and nullo sperm, consistent with a high frequency of nondisjunction and/or chromosome loss. These phenotypes of mus309 suggest that Dmblm functions in DNA double-strand break repair. The mutant Dmblm phenotypes were partially rescued by an extra copy of the DNA repair gene Ku70, indicating that the two genes functionally interact in vivo.


Assuntos
Antígenos Nucleares , DNA Helicases/genética , DNA Helicases/fisiologia , Proteínas de Ligação a DNA/genética , Drosophila melanogaster/fisiologia , Proteínas Nucleares/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/fisiologia , Alelos , Substituição de Aminoácidos , Animais , Síndrome de Bloom/genética , Quebra Cromossômica , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/fisiologia , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Feminino , Fertilidade , Genes de Insetos , Teste de Complementação Genética , Marcadores Genéticos , Autoantígeno Ku , Masculino , Mutagênese Insercional , Mutação , Não Disjunção Genética , Proteínas Nucleares/fisiologia , Fenótipo , RecQ Helicases , Recombinação Genética , Deleção de Sequência , Espermatozoides/fisiologia , Transgenes , Cromossomo Y/genética
12.
Sci Adv ; 5(1): eaau2307, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30613769

RESUMO

The solar convection zone is filled with turbulent convection in highly stratified plasma. Several theoretical and observational studies suggest that the numerical calculations overestimate the convection velocity. Since all deep convection zone calculations exclude the solar surface due to substantial temporal and spatial scale separations, the solar surface, which drives the thermal convection with efficient radiative cooling, has been thought to be the key to solve this discrepancy. Thanks to the recent development in massive supercomputers, we are successful in performing the comprehensive calculation covering the whole solar convection zone. We compare the results with and without the solar surface in the local domain and without the surface in the full sphere. The calculations do not include the rotation and the magnetic field. The surface region has an unexpectedly weak influence on the deep convection zone. We find that just including the solar surface cannot solve the problem.

13.
Equine Vet J ; 51(4): 506-509, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30472732

RESUMO

BACKGROUND: Repeated topical application of indomethacin is common in Japanese racehorses, despite the lack of pharmacokinetic data. OBJECTIVES: To determine the concentrations of indomethacin and its metabolite, desmethylindomethacin, in plasma and urine of Thoroughbreds topically treated repeatedly with indomethacin. STUDY DESIGN: In vivo experimental. METHODS: Seven female Thoroughbreds were topically treated with 50 g of 1% indomethacin cream per horse to the back and hips (500 mg of indomethacin/head/2400 cm2 , 0.21 g/cm2 ) for 3 consecutive days. Samples were pretreated by protein precipitation for plasma and liquid-liquid extraction with ethyl acetate after hydrolysis with hydrochloric acid for urine. The concentrations of indomethacin and desmethylindomethacin in plasma and urine were measured by liquid chromatography-mass spectrometry. RESULTS: Indomethacin was quantifiable in plasma up to 48-72 h and in urine up to 96 h after the final application. Desmethylindomethacin was quantifiable in plasma up to 48 h and in urine up to 72-96 h after the final application. MAIN LIMITATIONS: The relationship between the local and systemic indomethacin concentrations after the topical application was not clarified. CONCLUSIONS: Pharmacokinetic data were acquired for repeated topical administration of 1% indomethacin cream to Thoroughbreds. Hydrolysing urine samples with hydrochloric acid was effective for the analysis of indomethacin and its metabolite, and indomethacin may be an excellent marker analyte for doping tests. The estimated withdrawal time based on the limit of detection was 342 h.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Cavalos/sangue , Indometacina/farmacocinética , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/urina , Área Sob a Curva , Esquema de Medicação , Feminino , Meia-Vida , Cavalos/urina , Indometacina/administração & dosagem , Indometacina/sangue , Indometacina/urina
14.
Neuron ; 6(3): 421-30, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1848080

RESUMO

Recent binding studies in the central nervous system and other tissues provide evidence that the mammalian bombesin-like peptides, gastrin-releasing peptide (GRP) and neuromedin-B (NMB), exert their numerous physiological effects through at least two different receptors. We describe the structure and expression of a cloned NMB-preferring bombesin receptor (NMB-R) with properties distinct from a GRP-preferring bombesin receptor (GRP-R) reported previously. In particular, the NMB-R shows higher affinity binding to NMB than to GRP in BALB 3T3 fibroblasts expressing the cloned NMB-R. The distinct regional distribution of NMB-R and GRP-R mRNA in the brain suggests that both bombesin receptor subtypes play independent roles in mediating many of the dramatic effects of bombesin-like peptides in the central nervous system.


Assuntos
DNA/genética , Neurocinina B/análogos & derivados , Receptores de Neurotransmissores/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Sistema Nervoso Central/citologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/ultraestrutura , DNA/análise , DNA/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Peptídeo Liberador de Gastrina , Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Neurocinina B/metabolismo , Neurocinina B/fisiologia , Hibridização de Ácido Nucleico , Peptídeos/metabolismo , Peptídeos/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Bombesina , Receptores da Neurocinina-3 , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/fisiologia , Transfecção
15.
J Clin Invest ; 94(3): 1090-7, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8083350

RESUMO

We have found that an estrogen deficiency causes a marked increase in bone marrow cells. To examine the effect of estrogen on hemopoiesis, we characterized the increased population of bone marrow cells after ovariectomy (OVX). In OVX mice, the percentage of myeloid cells and granulocytes was decreased, whereas that of B220-positive B lymphocytes was selectively increased 2-4 wk after surgery. The total number of myeloid cells and granulocytes did not change appreciably, but that of B220-positive cells was greatly increased by OVX. When OVX mice were treated with estrogen, the increased B lymphopoiesis returned to normal. B220-positive cells were classified into two subpopulations, B220low and B220high. The majority of the B220low cells were negative for the IgM mu chain, whereas most of the B220high cells were mu-positive. OVX selectively increased the precursors of B lymphocytes identified by B220low. mu-negative phenotype, suggesting that an estrogen deficiency stimulates accumulation of B lymphocyte precursors. When bone marrow-derived stromal cells (ST2) were pretreated with estrogen then co-cultured with bone marrow cells in the presence of estrogen, the stromal cell-dependent B lymphopoiesis was greatly inhibited. The present study suggests that estrogen plays an important role in the regulation of B lymphocyte development in mouse bone marrow.


Assuntos
Linfócitos B/citologia , Células da Medula Óssea , Estradiol/farmacologia , Células-Tronco Hematopoéticas/citologia , Ovariectomia , Animais , Linfócitos B/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/imunologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Preparações de Ação Retardada , Estradiol/administração & dosagem , Estradiol/sangue , Feminino , Imunofluorescência , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/imunologia , Imunoglobulina M/análise , Cadeias mu de Imunoglobulina/análise , Camundongos , Camundongos Endogâmicos , Valores de Referência , Fatores de Tempo
16.
Traffic Inj Prev ; 18(5): 508-514, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28102701

RESUMO

OBJECTIVE: The objective of this study is to use a validated finite element model of the human body and a certified model of an anthropomorphic test dummy (ATD) to evaluate the effect of simulated precrash braking on driver kinematics, restraint loads, body loads, and computed injury criteria in 4 commonly injured body regions. METHODS: The Global Human Body Models Consortium (GHBMC) 50th percentile male occupant (M50-O) and the Humanetics Hybrid III 50th percentile models were gravity settled in the driver position of a generic interior equipped with an advanced 3-point belt and driver airbag. Fifteen simulations per model (30 total) were conducted, including 4 scenarios at 3 severity levels: median, severe, and the U.S. New Car Assessment Program (U.S.-NCAP) and 3 extra per model with high-intensity braking. The 4 scenarios were no precollision system (no PCS), forward collision warning (FCW), FCW with prebraking assist (FCW+PBA), and FCW and PBA with autonomous precrash braking (FCW + PBA + PB). The baseline ΔV was 17, 34, and 56.4 kph for median, severe, and U.S.-NCAP scenarios, respectively, and were based on crash reconstructions from NASS/CDS. Pulses were then developed based on the assumed precrash systems equipped. Restraint properties and the generic pulse used were based on literature. RESULTS: In median crash severity cases, little to no risk (<10% risk for Abbreviated injury Scale [AIS] 3+) was found for all injury measures for both models. In the severe set of cases, little to no risk for AIS 3+ injury was also found for all injury measures. In NCAP cases, highest risk was typically found with No PCS and lowest with FCW + PBA + PB. In the higher intensity braking cases (1.0-1.4 g), head injury criterion (HIC), brain injury criterion (BrIC), and chest deflection injury measures increased with increased braking intensity. All other measures for these cases tended to decrease. The ATD also predicted and trended similar to the human body models predictions for both the median, severe, and NCAP cases. Forward excursion for both models decreased across median, severe, and NCAP cases and diverged from each other in cases above 1.0 g of braking intensity. CONCLUSIONS: The addition of precrash systems simulated through reduced precrash speeds caused reductions in some injury criteria, whereas others (chest deflection, HIC, and BrIC) increased due to a modified occupant position. The human model and ATD models trended similarly in nearly all cases with greater risk indicated in the human model. These results suggest the need for integrated safety systems that have restraints that optimize the occupant's position during precrash braking and prior to impact.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/estatística & dados numéricos , Desaceleração , Equipamentos de Proteção , Acidentes de Trânsito/prevenção & controle , Fenômenos Biomecânicos , Simulação por Computador , Análise de Elementos Finitos , Humanos , Masculino , Manequins , Modelos Biológicos , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/prevenção & controle
17.
J Gen Physiol ; 52(2): 326-45, 1968 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4299623

RESUMO

The minimal presynaptic depolarization (MPD) for producing a detectable postsynaptic potential (PSP) was lower than 25 mv in normal or tetrodotoxin (TTX)-containing seawater. The MPD was about 10 mv when a small amount of tetraethylammonium ions (TEA) was injected into the presynaptic terminal. Application of linearly increasing depolarizing current to the normal presynaptic terminal at times produced a PSP before a presynaptic spike was evoked; the rate of rise of the resulting PSP was much slower than that of a PSP triggered by the normal presynaptic spike. A brief depolarizing pulse that preceded the presynaptic spike in normal seawater or the initial transient presynaptic depolarization in TTX decreased the PSP. It increased the PSP when it was applied during the spike or initial transient depolarization. Hyperpolarizing pulses had the reverse effect. The Off-PSP was also modified by inserting pulses at an initial part of the recovery phase of the strong presynaptic depolarization. These results indicate further that increases in Na(+) and K(+) conductance during presynaptic spike activity are not a requirement for transmitter release; the rate of release of transmitter can be controlled by electrical manipulation of the presynaptic terminal; there is a superficial correspondence between the time courses of presynaptic depolarization and the resulting PSP. Thus presynaptic depolarization appears to be only the first step in the series of events constituting excitation-transmitter release coupling. It may not be a necessary step for the release mechanism.


Assuntos
Sinapses/fisiologia , Animais , Cálcio/farmacologia , Césio/farmacologia , Eletrofisiologia , Técnicas In Vitro , Moluscos , Perfusão , Transmissão Sináptica , Compostos de Tetraetilamônio/farmacologia , Tetrodotoxina/farmacologia
18.
J Gen Physiol ; 49(4): 613-28, 1966 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-5943604

RESUMO

Depolarizations applied to voltage-clamped cells bathed in the normal solution disclose an initial inward current followed by a delayed outward current. The maximum slope conductance for the peak initial current is about 30 times the leak conductance, but the maximum slope conductance for the delayed current is only about 10 times the leak conductance. During depolarizations for as long as 30 sec, the outward current does not maintain a steady level, but declines first exponentially with a time constant of about 6 msec; it then tends to increase for the next few seconds; finally, it declines slowly with a half-time of about 5 sec. Concomitant with the changes of the outward current, the membrane conductance changes, although virtually no change in electromotive force occurs. Thus, the changes in the membrane conductance represent two phases of K inactivation, one rapidly developing, the other slowly occurring, and a phase of K reactivation, which is interposed between the two inactivations. In isosmotic KCl solution after a conditioning hyperpolarization there occurs an increase in K permeability upon depolarization. When the depolarizations are maintained, the increase of K permeability undergoes changes similar to those observed in the normal medium. The significance of the K inactivation is discussed in relation to the after-potential of the nerve cells.


Assuntos
Eletrofisiologia , Neurônios/fisiologia , Animais , Permeabilidade da Membrana Celular , Peixes , Técnicas In Vitro , Cinética , Cloreto de Potássio/farmacologia
19.
J Gen Physiol ; 50(11): 2579-601, 1967 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4296572

RESUMO

Depolarization of the presynaptic terminal by current produced a postsynaptic potential (PSP) which increased with increasing presynaptic polarization and then reached a plateau. Iontophoretic injection of tetraethylammonium ions (TEA) into the presynaptic axon near the terminal produced a prolonged presynaptic spike. The resulting PSP is increased in size and its time course closely followed that of the presynaptic spike. The presynaptic fiber no longer exhibited rectification and strong depolarizations revealed that the PSP reached a maximum with about 110 mv depolarization. Further depolarization produced a decrease in PSP amplitude and finally transmission was blocked. However, a PSP then always appeared on withdrawal of the depolarizing current. Under the conditions of these experiments, the PSP could be considered a direct measure of transmitter release. Bathing the TEA-injected synapse with concentrations of tetrodotoxin (TTX) sufficient to block spike activity in both pre- and postsynaptic axons did not greatly modify postsynaptic electrogenesis. However, doubling TTX concentration reversibly blocked PSP. Thus the permeability changes to Na and K accompanying the spike do not appear necessary for transmitter release. Some other processes related to the level of presynaptic polarization must be involved to explain the data. The inhibition of transmitter release by strong depolarizations appears to be related to Ca action. A membrane Ca current may also be necessary for normal transmitter release.


Assuntos
Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Compostos de Tetraetilamônio/farmacologia , Potenciais de Ação , Animais , Axônios/efeitos dos fármacos , Cálcio/metabolismo , Cálcio/farmacologia , Permeabilidade da Membrana Celular , Potenciais Evocados , Iontoforese , Potenciais da Membrana , Membranas/fisiologia , Moluscos , Potássio/metabolismo , Sódio/metabolismo , Sinapses/fisiologia , Tetrodotoxina/farmacologia
20.
J Mol Biol ; 209(4): 623-34, 1989 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-2685325

RESUMO

Apparent plasmid instability, i.e. progressive plasmid loss in a bacterial culture growing in the absence of selection for the plasmid, in an Escherichia coli recBC sbcBC mutant was investigated with two different ColE1 derivatives (pMB9 and pBR322) and a mini-F plasmid. The instability was most striking for pMB9 and much less, but still significant, for pBR322 and the mini-F. It was also dependent upon a subset of the genes involved in the RecF recombination pathway: in addition to the previously reported recA, recF and recJ mutations, a recO and a recQ mutation showed a total and a partial suppression, respectively, of the instability. Other recF-family mutations, recN and ruv, were without such an effect. Population analyses of the recBC sbcBC strain carrying pMB9 or the mini-F, as carried out by plating and Coulter counting, revealed marked loss of viability in plasmid-carrying cells, strongly implicating plasmid-mediated cell death in the apparent defect in plasmid maintenance. Analysis of intracellular plasmid DNA by pulsed-field gel electrophoresis combined with the in-agarose cell lysis technique showed that the instability was associated with the formation of plasmid multimers, with a good correlation between the degree of the instability and the amount of the multimers. The multimer formation was also dependent on the same subset of the RecF pathway genes as in the instability phenomenon. These results strongly suggest that the lethality is somehow caused by the multimer formation. Various DNase treatments of cell lysates showed that such multimers of pMB9 DNA comprised molecules of exonuclease-sensitive and exonuclease-resistant types. It was inferred that the former class, which showed electrophoretic mobilities corresponding to plain linear duplexes of approximately 200 x 10(3) to 2200 x 10(3) base-pairs, represented linear multimers possibly carrying circular structures at one end. The latter class, which remained in the origin, was thought to consist of circular multimers and/or linear multimers protected by circular structures at both ends against exonucleolytic attack.


Assuntos
Escherichia coli/genética , Genes Bacterianos , Genes Letais , Mutação , Plasmídeos/genética , Replicação do DNA , DNA Bacteriano/análise , Escherichia coli/crescimento & desenvolvimento , Transformação Bacteriana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA