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1.
Braz. j. biol ; 83: e244123, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278562

RESUMO

Abstract Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccoud's arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (−1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position −1237 with psychosis and anemia (p < 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p < 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


Resumo O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (−1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição −1237 com psicose e anemia (p < 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p < 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.


Assuntos
Humanos , Receptor Toll-Like 9/genética , Lúpus Eritematoso Sistêmico/genética , Brasil , Projetos Piloto , Predisposição Genética para Doença/genética , Frequência do Gene/genética
2.
Braz. j. biol ; 83: 1-5, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468819

RESUMO

Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccoud’s arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (−1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position −1237 with psychosis and anemia (p < 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p < 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (−1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição −1237 com psicose e anemia (p < 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p < 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.


Assuntos
Humanos , Artropatias/genética , Lúpus Eritematoso Sistêmico/genética , Receptor Toll-Like 9/análise
3.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469035

RESUMO

Abstract Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccouds arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position 1237 with psychosis and anemia (p 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


Resumo O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição 1237 com psicose e anemia (p 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.

4.
Plant Biol (Stuttg) ; 24(6): 987-997, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35869650

RESUMO

Genus Asarum (Aristolochiaceae) shows diverse floral morphology and is hypothesized to have diversified as a result of pollinator-mediated selection. Yet most aspects of their reproductive ecology, including pollinators, remain unclear. This study focuses on A. costatum and A. minamitanianum in Japan, a sister species pair having remarkable differences in calyx lobe length (10-20 mm and 70-180 mm, respectively). The objectives of this study are to elucidate multiple aspects of reproductive ecology of these two species and obtain evolutionary insights into floral organ elongation. We adopted combined approaches, including field observations, molecular analyses and cultivation experiments, such as pollinator observation for 3 years, fine-scale spatial genetic analysis of 769 individuals, paternity analysis based on 566 seeds over 4 years, and control pollination experiments. Both Asarum species had strong spatial genetic structures, indicating limited seed dispersal. Pollinator observation revealed that flies and ground-dwelling insects visited flowers of both species, but that the pollinator fauna differed between the species. The visitation rate of flies was extremely low but was more than twice as high in the species with an elongated floral appendage. Paternity analysis revealed A. minamitanianum was predominantly outcrossing, while A. costatum showed a wide range of selfing rates among fruits. These two Asarum species are likely adapted to fly pollination in the shady forest understorey, where available pollinator fauna is limited. In addition, although its function remains unclear, the elongated calyx lobe of A. minamitanianum could have evolved for effective pollen dispersal by attracting fly visitors.


Assuntos
Aristolochiaceae , Asarum , Dípteros , Animais , Flores/anatomia & histologia , Flores/genética , Polinização , Reprodução/genética
5.
Braz J Biol ; 83: e244123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161457

RESUMO

Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccoud's arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (-1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position -1237 with psychosis and anemia (p < 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p < 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


Assuntos
Lúpus Eritematoso Sistêmico , Receptor Toll-Like 9 , Brasil , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Humanos , Lúpus Eritematoso Sistêmico/genética , Projetos Piloto , Receptor Toll-Like 9/genética
7.
Hum Reprod ; 33(4): 694-705, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29401269

RESUMO

STUDY QUESTION: What are the impacts of elevated testosterone (T) and an obesogenic western-style diet (WSD), either independently or together, on fertility and metabolic adaptations of pregnancy in primates? SUMMARY ANSWER: Testosterone increases the time to achieve pregnancy, while a WSD reduces overall fertility, and the combination of testosterone and WSD additionally impairs glucose tolerance and causes pregnancy loss. WHAT IS KNOWN ALREADY: Both hyperandrogenemia and obesity are hallmarks of polycystic ovary syndrome, which is a leading cause of infertility among women worldwide. Female macaques receiving T and WSD beginning at puberty show increased metabolic, ovarian and uterine dysfunction in the non-pregnant state by 3 years of treatment. STUDY DESIGN, SIZE, DURATION: The same cohort of female rhesus macaques continued treatments from the time of puberty (2.5 years) to 4 years, including this fertility trial. There were four groups (n = 9-10/group): controls (C), T-treated (T; average total serum level 1.35 ng/ml), WSD-treated, and combined T and WSD-treated (T + WSD) females. PARTICIPANTS/MATERIALS, SETTING, METHODS: Females, which were typically having menstrual cycles, were paired for 4 days with a proven male breeder following the late follicular rise in circulating estradiol (≥100 pg/ml). The presence of sperm in the reproductive tract was used to confirm mating. Animals went through up to three successive rounds of mating until they became pregnant, as confirmed by a rise in circulating mCG during the late luteal phase and ultrasound evidence of a gestational sac at Day 30 post-mating (GD30). Placental vascular parameters were also measured at GD30. Metabolic measurements consisted of fasting levels of blood glucose and insulin at approximately GD30, 60, 90 and 115, as well as an intravenous (iv) glucose tolerance test (GTT) at GD115. MAIN RESULTS AND THE ROLE OF CHANCE: While all animals in the C and T groups eventually became pregnant, T-treated females on average had a greater interval to achieve pregnancy (P < 0.05). However, only ~70% of animals in the WSD and T + WSD groups became pregnant (P < 0.004). One pregnancy in T + WSD group resulted in an anembryonic pregnancy which miscarried around GD60, while another T + WSD female conceived with a rare identical twin pregnancy which required cessation due to impending fetal loss at GD106. Thus, the number of viable fetuses was less in the T + WSD group, compared to C, T or WSD. Placental blood volume at GD30 was reduced in all treatments compared to the C group (P < 0.05). Maternal P4 levels were elevated in the WSD (P < 0.03) group and E2 levels were elevated in T + WSD animals (P < 0.05). An increase in serum A4 levels throughout gestation was observed in all groups (P < 0.03) except WSD (P = 0.3). All groups displayed increased insulin resistance with pregnancy, as measured from the ivGTT during pregnancy. However, only the T + WSD group had a significant increase in fasting glucose levels and glucose clearance during the GTT indicating a worsened glucose tolerance. WSD treatment decreased female fetuses third trimester weights, but there was an interaction between WSD and T to increase female fetal weight when normalized to maternal weight. LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: The small number of pregnancies in the WSD and T + WSD groups hampers the ability to make definitive conclusions on effects during gestation. Also, the high fertility rate in the controls indicates the cohort was at their breeding prime age, which may impair the ability to observe subtle fertility defects. The low number of fetuses used for male and female analysis requires additional studies. WIDER IMPLICATIONS OF THE FINDINGS: The current findings strongly suggest that both hyperandrogenemia and obesity have detrimental effects on fertility and gestation in primates, which may be directly relevant to women with polycystic ovary syndrome. STUDY FUNDING/COMPETING INTEREST(S): All ONPRC Cores and Units were supported by NIH Grant P51 OD011092 awarded to ONPRC. Research reported in this publication was supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD) of the National Institutes of Health (NIH) under Award Number P50HD071836 (to R.L.S.). The authors have no competing conflict of interests to disclose.


Assuntos
Dieta Ocidental , Fertilidade/fisiologia , Hiperandrogenismo/complicações , Síndrome Metabólica/complicações , Maturidade Sexual/fisiologia , Testosterona/sangue , Animais , Feminino , Hiperandrogenismo/sangue , Hiperandrogenismo/fisiopatologia , Resistência à Insulina/fisiologia , Macaca , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Gravidez
9.
Cereb Cortex ; 28(8): 2725-2740, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981586

RESUMO

Neocortical injury initiates a cascade of events, some of which result in maladaptive epileptogenic reorganization of surviving neural circuits. Research focused on molecular and organizational changes that occur following trauma may reveal processes that underlie human post-traumatic epilepsy (PTE), a common and unfortunate consequence of traumatic brain injury. The latency between injury and development of PTE provides an opportunity for prophylactic intervention, once the key underlying mechanisms are understood. In rodent neocortex, injury to pyramidal neurons promotes axonal sprouting, resulting in increased excitatory circuitry that is one important factor promoting epileptogenesis. We used laser-scanning photostimulation of caged glutamate and whole-cell recordings in in vitro slices from injured neocortex to assess formation of new excitatory synapses, a process known to rely on astrocyte-secreted thrombospondins (TSPs), and to map the distribution of maladaptive circuit reorganization. We show that this reorganization is centered principally in layer V and associated with development of epileptiform activity. Short-term blockade of the synaptogenic effects of astrocyte-secreted TSPs with gabapentin (GBP) after injury suppresses the new excitatory connectivity and epileptogenesis for at least 2 weeks. Results reveal that aberrant circuit rewiring is progressive in vivo and provide further rationale for prophylactic anti-epileptogenic use of gabapentinoids following cortical trauma.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia Pós-Traumática/etiologia , Epilepsia Pós-Traumática/prevenção & controle , Gabapentina/farmacologia , Neocórtex/patologia , Animais , Animais Recém-Nascidos , Mapeamento Encefálico , Modelos Animais de Doenças , Estimulação Elétrica , Agonistas de Aminoácidos Excitatórios/toxicidade , Ácido Glutâmico/toxicidade , Técnicas In Vitro , Lasers/efeitos adversos , Masculino , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Ratos
10.
Hum Reprod ; 32(9): 1880-1891, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854721

RESUMO

STUDY QUESTION: Does developmental exposure to the combination of hyperandrogenemia and western-style diet (WSD) worsen adult metabolic function compared to either treatment alone? SUMMARY ANSWER: Young female rhesus macaques treated for 3 years, beginning at menarche, with combined testosterone (T) and WSD have increased weight gain and insulin resistance compared to controls and animals treated with either T or WSD alone. WHAT IS KNOWN ALREADY: Hyperandrogenemia is a well-established component of polycystic ovary syndrome (PCOS) and can be observed in peripubertal girls, indicating a potential pubertal onset of the disease. Obesity is often associated with hyperandrogenemia in peripubertal girls, and overweight girls appear to be at higher risk for the development of PCOS later in life. STUDY DESIGN, SIZE, DURATION: Juvenile (2.5- year old) female rhesus macaques were divided into four groups (n = 10/group): control animals receiving cholesterol implants and a control diet with 15% of calories derived from fat (C), animals receiving T implants (mean serum levels: 1.35 ± 0.01 ng/ml) and a control diet (T), animals receiving a cholesterol implant and a WSD with 36% of calories derived from fat (WSD) and animals receiving a T implant and a WSD (T + WSD). Animals were maintained on the treatments for 36 months and were 5.5 years old at study completion. PARTICIPANTS/MATERIALS, SETTING, METHODS: Metabolic testing consisted of body measurements including weight, dual-energy X-ray absorptiometry scans, activity monitoring, and glucose tolerance testing at zero months and at least once every 12 months for the remainder of the study. Indirect calorimetry and serum hormone assays were performed following 36 months of treatment. MAIN RESULTS AND THE ROLE OF CHANCE: Body weight and fat mass gain were significantly increased in T + WSD at 24 and 36 months of treatment compared to the other three groups. Log transformed fasting insulin and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) were significantly increased in T + WSD animals at 3 years of treatment compared to all other groups. T-treatment caused a greater rate of decline in activity after 18 months, while food intake and metabolic rate were largely unaffected by treatments. LIMITATIONS REASONS FOR CAUTION: Variability was present in the metabolic parameters measured; however, this is similar to the heterogeneity observed in human populations. WIDER IMPLICATIONS OF THE FINDINGS: Chronic hyperandrogenemia beginning at puberty may exacerbate metabolic dysfunction in women consuming a WSD and account for the increased rates of obesity and insulin resistance observed in PCOS patients. Counseling of female patient populations with elevated androgens about the potential benefit of consuming a lower fat diet could improve long-term metabolic health outcomes. STUDY FUNDING/COMPETING INTEREST(S): Eunice Kennedy Shriver National Institute of Child Health & Human Development P50HD071836 and Oregon National Primate Center Grant P51 OD011092. The authors have no competing conflict of interests to disclose.


Assuntos
Adiposidade/fisiologia , Peso Corporal/fisiologia , Dieta Ocidental , Hiperandrogenismo/metabolismo , Resistência à Insulina/fisiologia , Testosterona/farmacologia , Absorciometria de Fóton , Adiposidade/efeitos dos fármacos , Animais , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Feminino , Teste de Tolerância a Glucose , Hiperandrogenismo/sangue , Macaca mulatta , Testosterona/sangue
11.
J Neuroendocrinol ; 29(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28561903

RESUMO

The underlying hypothalamic neurocircuitry by which metabolism and feeding regulates reproductive function has been well-studied in the rodent; however, recent data have demonstrated significant neuroanatomical differences in the human brain. The present study had three objectives, centred on arcuate nucleus neuropeptides regulating feeding and reproduction: (i) to characterise coexpression patterns in the female nonhuman primate; (ii) to establish whether these neuronal populations make potential contacts with gonadotophin-releasing hormone (GnRH) neurones; and (iii) to determine whether these contacts differ between the low and high GnRH-releasing states of pre-puberty and adulthood, respectively. Female nonhuman primates have several coexpression patterns of hypothalamic neuropeptides that differ from those reported in rodents. Cocaine- and amphetamine-regulated transcript (CART) is not coexpressed with pro-opiomelanocortin but instead with neuropeptide Y (NPY). CART is also expressed in a subpopulation of kisspeptin cells in the nonhuman primate, similar to observations in humans but diverging from findings in rodents. Very few GnRH-expressing neurones received close appositions from double-labelled kisspeptin/CART fibres; however, both single-labelled kisspeptin and CART fibres were in frequent apposition with GnRH neurones, with no differences between prepubertal and adult animals. NPY/agouti-related peptide (AgRP) coexpressing fibres contacted significantly more GnRH neurones in prepubertal animals than adults, consistent with increased NPY and AgRP mRNA observed in prepubertal animals. The findings of the present study detail significant differences in arcuate nucleus neuropeptide coexpression in the monkey compared to the rodent and are consistent with the hypothesis that arcuate nucleus NPY/AgRP neurones play an inhibitory role in controlling GnRH neuronal regulation in the prepubertal primate.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Macaca mulatta , Fatores Etários , Proteína Relacionada com Agouti/metabolismo , Animais , Contagem de Células , Feminino , Kisspeptinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo
12.
Neurobiol Dis ; 91: 166-81, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26956396

RESUMO

Lesioned neuronal circuits form new functional connections after a traumatic brain injury (TBI). In humans and animal models, aberrant excitatory connections that form after TBI may contribute to the pathogenesis of post-traumatic epilepsy. Partial neocortical isolation ("undercut" or "UC") leads to altered neuronal circuitry and network hyperexcitability recorded in vivo and in brain slices from chronically lesioned neocortex. Recent data suggest a critical period for maladaptive excitatory circuit formation within the first 3days post UC injury (Graber and Prince 1999, 2004; Li et al. 2011, 2012b). The present study focuses on alterations in excitatory connectivity within this critical period. Immunoreactivity (IR) for growth-associated protein (GAP)-43 was increased in the UC cortex 3days after injury. Some GAP-43-expressing excitatory terminals targeted the somata of layer V pyramidal (Pyr) neurons, a domain usually innervated predominantly by inhibitory terminals. Immunocytochemical analysis of pre- and postsynaptic markers showed that putative excitatory synapses were present on somata of these neurons in UC neocortex. Excitatory postsynaptic currents from UC layer V Pyr cells displayed properties consistent with perisomatic inputs and also reflected an increase in the number of synaptic contacts. Laser scanning photostimulation (LSPS) experiments demonstrated reorganized excitatory connectivity after injury within the UC. Concurrent with these changes, spontaneous epileptiform bursts developed in UC slices. Results suggest that aberrant reorganization of excitatory connectivity contributes to early neocortical hyperexcitability in this model. The findings are relevant for understanding the pathophysiology of neocortical post-traumatic epileptogenesis and are important in terms of the timing of potential prophylactic treatments.


Assuntos
Potenciais Pós-Sinápticos Excitadores/fisiologia , Neocórtex/fisiopatologia , Sinapses/fisiologia , Transmissão Sináptica/fisiologia , Traumatismos do Sistema Nervoso/fisiopatologia , Animais , Proteína GAP-43/metabolismo , Masculino , Inibição Neural/fisiologia , Técnicas de Patch-Clamp/métodos , Células Piramidais/fisiologia , Ratos
13.
Science ; 349(6249): 734-8, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26273055

RESUMO

Human vocal development occurs through two parallel interactive processes that transform infant cries into more mature vocalizations, such as cooing sounds and babbling. First, natural categories of sounds change as the vocal apparatus matures. Second, parental vocal feedback sensitizes infants to certain features of those sounds, and the sounds are modified accordingly. Paradoxically, our closest living ancestors, nonhuman primates, are thought to undergo few or no production-related acoustic changes during development, and any such changes are thought to be impervious to social feedback. Using early and dense sampling, quantitative tracking of acoustic changes, and biomechanical modeling, we showed that vocalizations in infant marmoset monkeys undergo dramatic changes that cannot be solely attributed to simple consequences of growth. Using parental interaction experiments, we found that contingent parental feedback influences the rate of vocal development. These findings overturn decades-old ideas about primate vocalizations and show that marmoset monkeys are a compelling model system for early vocal development in humans.


Assuntos
Callithrix/crescimento & desenvolvimento , Vocalização Animal , Acústica , Animais , Fenômenos Biomecânicos , Callithrix/fisiologia , Callithrix/psicologia , Feminino , Masculino , Modelos Biológicos , Tono Muscular , Prega Vocal/crescimento & desenvolvimento , Prega Vocal/fisiologia
14.
J Frailty Aging ; 3(4): 211-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27048859

RESUMO

BACKGROUND: Body composition is an important component of health related fitness. Near-infrared spectroscopy (NIRS) is a non-invasive, simple and rapid method of assessing body fat percentage. However, it is unknown whether NIRS can accurately estimate FFM in community-dwelling frail elderly. OBJECTIVES: This study aimed to compare NIRS with bioelectrical impedance analysis (BIA) in FFM measurement. DESIGN: Cross-sectional study. SETTING: Shizuoka, Japan. PARTICIPANTS: The study population comprised 53 community-dwelling frail elderly (15 men, 38 women; mean age 84.8±6.4 years; body mass index 19.7±3.5 kg/m2). MEASUREMENT: FFM and percentage fat mass (%FM) were estimated using a NIRS device at two sites (biceps and calf) and compared to body composition measured by BIA. Simple linear regression and Bland-Altman analyses were used to determine agreement between the methods. RESULTS: FFM determined by BIA highly correlated with that determined by NIRS at both the biceps and calf (r=0.92 for both; p<0.001). The correlation coefficients for %FM estimated by NIRS were slightly lower (r=0.70 for biceps; r=0.66 for calf). In NIRS assessments, systematic biases were found for %FM but not for FFM. CONCLUSION: NIRS has significant potential for body composition analysis. Further comparative and longitudinal studies need to be conducted using an agreed reference analysis method to find a simple and more suitable method that can be applied among the community-dwelling frail elderly.

15.
J Neuropathol Exp Neurol ; 72(10): 919-32, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24042195

RESUMO

Astrocytes have emerged as active participants of synaptic transmission and are increasingly implicated in neurologic disorders including epilepsy. Adult glial fibrillary acidic protein (GFAP)-positive hippocampal astrocytes are not known for ionotropic glutamate receptor expression under basal conditions. Using a chemoconvulsive status epilepticus (SE) model of temporal lobe epilepsy, we show by immunohistochemistry and colocalization analysis that reactive hippocampal astrocytes express kainate receptor (KAR) subunits after SE. In the CA1 region, GluK1, GluK2/3, GluK4, and GluK5 subunit expression was observed in GFAP-positive astrocytes during the seizure-free or "latent" period 1 week after SE. At 8 weeks after SE, a time after SE when spontaneous behavioral seizures occur, the GluK1 and GluK5 subunits remained expressed at significant levels. Kainate receptor subunit expression was found in astrocytes in the hippocampus and surrounding cortex but not in GFAP-positive astrocytes of striatum, olfactory bulb, or brainstem. To examine hippocampal KAR expression more broadly, astroglial-enriched tissue fractions were prepared from dissected hippocampi and were found to have greater GluK4 expression after SE than controls. These results demonstrate that astrocytes begin to express KARs after seizure activity and suggest that their expression may contribute to the pathophysiology of epilepsy.


Assuntos
Astrócitos/metabolismo , Hipocampo/metabolismo , Subunidades Proteicas/metabolismo , Receptores de Ácido Caínico/metabolismo , Estado Epiléptico/metabolismo , Animais , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/genética , Gliose/metabolismo , Ácido Caínico , Masculino , Neurônios/metabolismo , Pilocarpina , Ratos , Ratos Sprague-Dawley , Convulsões/metabolismo , Estado Epiléptico/induzido quimicamente
16.
Philos Trans A Math Phys Eng Sci ; 371(1997): 20120158, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23858488

RESUMO

This paper presents a unified mathematical derivation of the asymptotic behaviour of the three main forms of partial directed coherence (PDC). Numerical examples are used to contrast PDC, gPDC (generalized PDC) and iPDC (information PDC) as to meaning and applicability and, more importantly, to show their essential statistical equivalence insofar as connectivity inference is concerned.


Assuntos
Algoritmos , Modelos Biológicos , Modelos Estatísticos , Simulação por Computador
17.
Int J Obes (Lond) ; 37(2): 254-62, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22450853

RESUMO

OBJECTIVE: The link between maternal under-nutrition and cardiovascular disease (CVD) in the offspring later in life is well recognized, but the impact of maternal over-nutrition on the offspring's cardiovascular function and subsequent risk for CVD later in life remains unclear. Here, we investigated the impact of maternal exposure to a high-fat/calorie diet (HFD) during pregnancy and early postnatal period on endothelial function of the offspring in a nonhuman primate model. METHODS: Offspring, naturally born to either a control (CTR) diet (14% fat calories) or a HFD (36% fat calories) consumption dam, were breast-fed until weaning at about 8 months of age. After weaning, the offspring were either maintained on the same diet (CTR/CTR, HFD/HFD), or underwent a diet switch (CTR/HFD, HFD/CTR). Blood samples and arterial tissues were collected at necropsy when the animals were about 13 months of age. RESULTS: HFD/HFD juveniles displayed an increased plasma insulin level and glucose-stimulated insulin secretion in comparison with CTR/CTR. In abdominal aorta, but not the renal artery, acetylcholine-induced vasorelaxation was decreased remarkably for HFD/HFD juveniles compared with CTR/CTR. HFD/HFD animals also showed a thicker intima wall and an abnormal vascular-morphology, concurrent with elevated expression levels of several markers related to vascular inflammation and fibrinolytic function. Diet-switching animals (HFD/CTR and CTR/HFD) displayed modest damage on the abdominal vessel. CONCLUSION: Our data indicate that maternal HFD exposure impairs offspring's endothelial function. Both early programming events and postweaning diet contribute to the abnormalities that could be reversed partially by diet intervention.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Retardo do Crescimento Fetal/metabolismo , Fígado/metabolismo , Obesidade/sangue , Hipernutrição/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Animais , Animais Recém-Nascidos , Espessura Intima-Media Carotídea , Modelos Animais de Doenças , Endotélio Vascular/patologia , Jejum/sangue , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Regulação da Expressão Gênica no Desenvolvimento , Macaca , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Troca Materno-Fetal , Obesidade/complicações , Obesidade/patologia , Hipernutrição/complicações , Insuficiência Placentária/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Primatas , Reação em Cadeia da Polimerase em Tempo Real , Desmame
18.
Neurochem Int ; 63(7): 660-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23266599

RESUMO

Status epilepticus (SE) is a life threatening condition that often precedes the development of epilepsy. Traditional treatments for epilepsy have been focused on targeting neuronal mechanisms contributing to hyperexcitability, however, approximately 30% of patients with epilepsy do not respond to existing neurocentric pharmacotherapies. A growing body of evidence has demonstrated that profound changes in the morphology and function of astrocytes accompany SE and persist in epilepsy. Astrocytes are increasingly recognized for their diverse roles in modulating neuronal activity, and understanding the changes in astrocytes following SE could provide important clues about the mechanisms underlying seizure generation and termination. By understanding the contributions of astrocytes to the network changes underlying epileptogenesis and the development of epilepsy, we will gain a greater appreciation of the contributions of astrocytes to dynamic circuit changes, which will enable us to develop more successful therapies to prevent and treat epilepsy. This review summarizes changes in astrocytes following SE in animal models and human temporal lobe epilepsy and addresses the functional consequences of those changes that may provide clues to the process of epileptogenesis.


Assuntos
Astrócitos/patologia , Epilepsia/patologia , Estado Epiléptico/patologia , Anticonvulsivantes/uso terapêutico , Astrócitos/metabolismo , Barreira Hematoencefálica , Sinalização do Cálcio , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Epilepsia/metabolismo , Humanos , Receptores de Glutamato/metabolismo , Estado Epiléptico/complicações , Estado Epiléptico/metabolismo
19.
Phys Rev Lett ; 108(10): 105302, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22463420

RESUMO

There are a number of distinct signatures of superfluids, one of which is the appearance of quantized vortices. There have been some attempts to understand the putative supersolid 4He in the vortex framework, but no conclusive evidence that supports the existence of the vortices has been reported. Here, we investigate the rotation velocity dependence of the torsional oscillation of solid 4He at various temperatures. The velocity sweep reveals intriguing periodic staircaselike features below about 300 mK. The staircase patterns show remarkable periodicity, and we interpret these patterns as a consequence of vortex injection. However, there are some features that cannot be accounted for with simple injection of vortices into superfluid, and further investigation is required.

20.
J Bone Joint Surg Br ; 94(3): 308-14, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22371535

RESUMO

We have previously described the mid- to long-term results of conventional simple varus intertrochanteric osteotomy for osteonecrosis of the femoral head, showing that 19 of the 26 hips had good or excellent results. We extended the follow-up to a mean of 18.1 years (10.5 to 26) including a total of 34 hips in 28 patients, with a mean age at surgery of 33 years (19 to 53). There were 18 men and ten women and 25 hips (74%) had a satisfactory result with a Harris hip score ≥ 80. In all, six hips needed total hip replacement (THR) or hemiarthroplasty. The collapse of the femoral head or narrowing of the joint space was found to have progressed in nine hips (26%). Leg shortening after osteotomy was a mean of 19 mm (8 to 36). With conversion to THR or hemiarthroplasty as the endpoint, the ten-year survival rate was 88.2% (95% confidence interval (CI) 82.7 to 93.7) and the 20-year survival rate was 79.7% (95% CI 72.1 to 87.3); four hips were converted at ten years and other two hips were converted at 20 years. Shortening of the leg after osteotomy remains a concern; however, the conventional varus half-wedge osteotomy provides favourable long-term results in hips with less than two-thirds of the medial part of the femoral head affected by necrotic bone and with normal bone superolaterally.


Assuntos
Necrose da Cabeça do Fêmur/cirurgia , Fêmur/cirurgia , Osteotomia/métodos , Adulto , Alcoolismo/complicações , Artroplastia de Quadril , Métodos Epidemiológicos , Feminino , Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/etiologia , Glucocorticoides/efeitos adversos , Humanos , Desigualdade de Membros Inferiores/etiologia , Masculino , Pessoa de Meia-Idade , Osteotomia/efeitos adversos , Radiografia , Resultado do Tratamento , Adulto Jovem
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