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1.
Diabetologia ; 63(10): 2150-2157, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32757153

RESUMEN

AIMS/HYPOTHESIS: Assisted reproductive technology (ART) is the most widely used treatment for infertility and has resulted in millions of births worldwide. The safety of the offspring has been of the utmost concern. Previous studies suggested an increase in metabolic disorders in offspring later in life. The aim of the present study was to investigate metabolic changes at age 6-10 years in offspring conceived as a result of in vitro fertilisation/intracytoplasmic sperm injection (IVF/ICSI). METHODS: A total of 380 children born from IVF/ICSI and a matched control group of 380 naturally conceived children, all aged 6-10 years, were recruited. Anthropometric measures, ultrasound and serum tests were performed for body mass, glucose metabolism and lipid profiles, and examination of vasculature structure. RESULTS: The children conceived by ART showed significantly higher fasting blood glucose and serum insulin levels and HOMA-IR (adjusted ß [95% CI]: fasting blood glucose 0.49 [0.42, 0.55]; loge-transformed insulin 0.28 [0.20, 0.35]; loge-transformed HOMA-IR 0.38 [0.30, 0.46]), as well as a lower HOMA-B and serum apolipoprotein A (ApoA) levels (adjusted ß [95% CI]: loge-transformed HOMA-B -0.19 [-0.27, -0.11]; ApoA -0.17 [-0.21, -0.13]), when compared with the control group. Furthermore, the ultrasound scan indicated elevated carotid intima-media thickness in children conceived by ART (ß 0.13 [95% CI 0.12, 0.13]). CONCLUSIONS/INTERPRETATION: Children conceived by IVF/ICSI have a less favourable glucose and cardiovascular metabolic profile in childhood when compared with naturally conceived children. The underlying mechanisms and potential long-term consequences need to be elucidated in future studies. Graphical abstract.


Asunto(s)
Apolipoproteínas A/sangre , Glucemia/metabolismo , Grosor Intima-Media Carotídeo , Fertilización In Vitro , Insulina/sangre , Efectos Tardíos de la Exposición Prenatal/metabolismo , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Niño , Femenino , Humanos , Resistencia a la Insulina , Masculino , Edad Materna , Embarazo , Técnicas Reproductivas Asistidas , Inyecciones de Esperma Intracitoplasmáticas
2.
Nature ; 491(7426): 769-73, 2012 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-23103873

RESUMEN

In the course of primary infection with herpes simplex virus 1 (HSV-1), children with inborn errors of toll-like receptor 3 (TLR3) immunity are prone to HSV-1 encephalitis (HSE). We tested the hypothesis that the pathogenesis of HSE involves non-haematopoietic CNS-resident cells. We derived induced pluripotent stem cells (iPSCs) from the dermal fibroblasts of TLR3- and UNC-93B-deficient patients and from controls. These iPSCs were differentiated into highly purified populations of neural stem cells (NSCs), neurons, astrocytes and oligodendrocytes. The induction of interferon-ß (IFN-ß) and/or IFN-λ1 in response to stimulation by the dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) was dependent on TLR3 and UNC-93B in all cells tested. However, the induction of IFN-ß and IFN-λ1 in response to HSV-1 infection was impaired selectively in UNC-93B-deficient neurons and oligodendrocytes. These cells were also much more susceptible to HSV-1 infection than control cells, whereas UNC-93B-deficient NSCs and astrocytes were not. TLR3-deficient neurons were also found to be susceptible to HSV-1 infection. The rescue of UNC-93B- and TLR3-deficient cells with the corresponding wild-type allele showed that the genetic defect was the cause of the poly(I:C) and HSV-1 phenotypes. The viral infection phenotype was rescued further by treatment with exogenous IFN-α or IFN-ß ( IFN-α/ß) but not IFN-λ1. Thus, impaired TLR3- and UNC-93B-dependent IFN-α/ß intrinsic immunity to HSV-1 in the CNS, in neurons and oligodendrocytes in particular, may underlie the pathogenesis of HSE in children with TLR3-pathway deficiencies.


Asunto(s)
Sistema Nervioso Central/patología , Herpesvirus Humano 1/inmunología , Células Madre Pluripotentes Inducidas/citología , Receptor Toll-Like 3/deficiencia , Astrocitos/inmunología , Astrocitos/virología , Biomarcadores , Diferenciación Celular , Linaje de la Célula , Separación Celular , Células Cultivadas , Sistema Nervioso Central/citología , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/virología , Niño , Susceptibilidad a Enfermedades , Encefalitis por Herpes Simple/inmunología , Encefalitis por Herpes Simple/metabolismo , Encefalitis por Herpes Simple/patología , Encefalitis por Herpes Simple/virología , Herpesvirus Humano 1/patogenicidad , Humanos , Inmunidad Innata , Células Madre Pluripotentes Inducidas/virología , Interferones/inmunología , Proteínas de Transporte de Membrana/deficiencia , Proteínas de Transporte de Membrana/genética , Células-Madre Neurales/inmunología , Células-Madre Neurales/virología , Neuronas/inmunología , Neuronas/patología , Neuronas/virología , Oligodendroglía/inmunología , Oligodendroglía/patología , Oligodendroglía/virología , Receptor Toll-Like 3/genética
3.
J Biol Chem ; 291(35): 18176-89, 2016 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-27387502

RESUMEN

Activation of IKKß is the key step in canonical activation of NF-κB signaling. Extensive work has provided insight into the mechanisms underlying IKKß activation through the identification of context-specific regulators. However, the molecular processes responsible for its negative regulation are not completely understood. Here, we identified KLHL21, a member of the Kelch-like gene family, as a novel negative regulator of IKKß. The expression of KLHL21 was rapidly down-regulated in macrophages upon treatment with proinflammatory stimuli. Overexpression of KLHL21 inhibited the activation of IKKß and degradation of IκBα, whereas KLHL21 depletion via siRNA showed the opposite results. Coimmunoprecipitation assays revealed that KLHL21 specifically bound to the kinase domain of IKKß via its Kelch domains and that this interaction was gradually attenuated upon TNFα treatment. Furthermore, KLHL21 did not disrupt the interaction between IKKß and TAK1, TRAF2, or IκBα. Also, KLHL21 did not require its E3 ubiquitin ligase activity for IKKß inhibition. Our findings suggest that KLHL21 may exert its inhibitory function by binding to the kinase domain and sequestering the region from potential IKKß inducers. Taken together, our data clearly demonstrate that KLHL21 negatively regulates TNFα-activated NF-κB signaling via targeting IKKß, providing new insight into the mechanisms underlying NF-κB regulation in cells.


Asunto(s)
Quinasa I-kappa B/metabolismo , Proteínas de Microfilamentos/metabolismo , Transducción de Señal/fisiología , Animales , Humanos , Quinasa I-kappa B/genética , Quinasas Quinasa Quinasa PAM/genética , Quinasas Quinasa Quinasa PAM/metabolismo , Ratones , Proteínas de Microfilamentos/genética , FN-kappa B/genética , FN-kappa B/metabolismo , Células RAW 264.7 , Factor 2 Asociado a Receptor de TNF/genética , Factor 2 Asociado a Receptor de TNF/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
4.
J Neurosci ; 35(33): 11462-81, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26290227

RESUMEN

The derivation of somatic motoneurons (MNs) from ES cells (ESCs) after exposure to sonic hedgehog (SHH) and retinoic acid (RA) is one of the best defined, directed differentiation strategies to specify fate in pluripotent lineages. In mouse ESCs, MN yield is particularly high after RA + SHH treatment, whereas human ESC (hESC) protocols have been generally less efficient. In an effort to optimize yield, we observe that functional MNs can be derived from hESCs at high efficiencies if treated with patterning molecules at very early differentiation steps before neural induction. Remarkably, under these conditions, equal numbers of human MNs were obtained in the presence or absence of SHH exposure. Using pharmacological and genetic strategies, we demonstrate that early RA treatment directs MN differentiation independently of extrinsic SHH activation by suppressing the induction of GLI3. We further demonstrate that neural induction triggers a switch from a poised to an active chromatin state at GLI3. Early RA treatment prevents this switch by direct binding of the RA receptor at the GLI3 promoter. Furthermore, GLI3 knock-out hESCs can bypass the requirement for early RA patterning to yield MNs efficiently. Our data demonstrate that RA-mediated suppression of GLI3 is sufficient to generate MNs in an SHH-independent manner and that temporal changes in exposure to patterning factors such as RA affect chromatin state and competency of hESC-derived lineages to adopt specific neuronal fates. Finally, our work presents a streamlined platform for the highly efficient derivation of human MNs from ESCs and induced pluripotent stem cells. SIGNIFICANCE STATEMENT: Our study presents a rapid and efficient protocol to generate human motoneurons from embryonic and induced pluripotent stem cells. Surprisingly, and in contrast to previous work, motoneurons are generated in the presence of retinoic acid but in the absence of factors that activate sonic hedgehog signaling. We show that early exposure to retinoic acid modulates the chromatin state of cells to be permissive for motoneuron generation and directly suppresses the induction of GLI3, a negative regulator of SHH signaling. Therefore, our data point to a novel mechanism by which retinoic acid exposure can bypass the requirement for extrinsic SHH treatment during motoneuron induction.


Asunto(s)
Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Proteínas Hedgehog/farmacología , Factores de Transcripción de Tipo Kruppel/metabolismo , Neuronas Motoras/citología , Proteínas del Tejido Nervioso/metabolismo , Tretinoina/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Células Cultivadas , Células Madre Embrionarias/efectos de los fármacos , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/fisiología , Humanos , Masculino , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Tretinoina/farmacología , Proteína Gli3 con Dedos de Zinc
5.
Neurobiol Dis ; 85: 81-92, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26459112

RESUMEN

Absence seizures occur in several types of human epilepsy and result from widespread, synchronous feedback between the cortex and thalamus that produces brief episodes of loss of consciousness. Genetic rodent models have been invaluable for investigating the pathophysiological basis of these seizures. Here, we identify tetratricopeptide-containing Rab8b-interacting protein (TRIP8b) knockout mice as a new model of absence epilepsy, featuring spontaneous spike-wave discharges on electroencephalography (EEG) that are the electrographic hallmark of absence seizures. TRIP8b is an auxiliary subunit of the hyperpolarization-activated cyclic-nucleotide-gated (HCN) channels, which have previously been implicated in the pathogenesis of absence seizures. In contrast to mice lacking the pore-forming HCN channel subunit HCN2, TRIP8b knockout mice exhibited normal cardiac and motor function and a less severe seizure phenotype. Evaluating the circuit that underlies absence seizures, we found that TRIP8b knockout mice had significantly reduced HCN channel expression and function in thalamic-projecting cortical layer 5b neurons and thalamic relay neurons, but preserved function in inhibitory neurons of the reticular thalamic nucleus. Our results expand the known roles of TRIP8b and provide new insight into the region-specific functions of TRIP8b and HCN channels in constraining cortico-thalamo-cortical excitability.


Asunto(s)
Corteza Cerebral/fisiopatología , Epilepsia Tipo Ausencia/fisiopatología , Proteínas de la Membrana/deficiencia , Neuronas/fisiología , Tálamo/fisiopatología , Animales , Western Blotting , Modelos Animales de Enfermedad , Electrocardiografía , Electrocorticografía , Electrodos Implantados , Epilepsia Tipo Ausencia/genética , Inmunohistoquímica , Masculino , Potenciales de la Membrana/fisiología , Proteínas de la Membrana/genética , Ratones Noqueados , Actividad Motora/fisiología , Técnicas de Placa-Clamp , Peroxinas , Prueba de Desempeño de Rotación con Aceleración Constante , Eliminación de Secuencia , Técnicas de Cultivo de Tejidos
6.
Anesthesiology ; 122(5): 1047-59, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25782754

RESUMEN

BACKGROUND: The thalamus is thought to be crucially involved in the anesthetic state. Here, we investigated the effect of the inhaled anesthetic xenon on stimulus-evoked thalamocortical network activity and on excitability of thalamocortical neurons. Because hyperpolarization-activated, cyclic nucleotide-gated cation (HCN) channels are key regulators of neuronal excitability in the thalamus, the effect of xenon on HCN channels was examined. METHODS: The effects of xenon on thalamocortical network activity were investigated in acutely prepared brain slices from adult wild-type and HCN2 knockout mice by means of voltage-sensitive dye imaging. The influence of xenon on single-cell excitability in brain slices was investigated using the whole-cell patch-clamp technique. Effects of xenon on HCN channels were verified in human embryonic kidney cells expressing HCN2 channels. RESULTS: Xenon concentration-dependently diminished thalamocortical signal propagation. In neurons, xenon reduced HCN channel-mediated Ih current amplitude by 33.4 ± 12.2% (at -133 mV; n = 7; P = 0.041) and caused a left-shift in the voltage of half-maximum activation (V1/2) from -98.8 ± 1.6 to -108.0 ± 4.2 mV (n = 8; P = 0.035). Similar effects were seen in human embryonic kidney cells. The impairment of HCN channel function was negligible when intracellular cyclic adenosine monophosphate level was increased. Using HCN2 mice, we could demonstrate that xenon did neither attenuate in vitro thalamocortical signal propagation nor did it show sedating effects in vivo. CONCLUSIONS: Here, we clearly showed that xenon impairs HCN2 channel function, and this impairment is dependent on intracellular cyclic adenosine monophosphate levels. We provide evidence that this effect reduces thalamocortical signal propagation and probably contributes to the hypnotic properties of xenon.


Asunto(s)
Anestésicos por Inhalación/farmacología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Xenón/farmacología , Animales , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , AMP Cíclico/metabolismo , Humanos , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/genética , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Red Nerviosa/citología , Red Nerviosa/efectos de los fármacos , Neuronas/efectos de los fármacos , Técnicas de Placa-Clamp , Canales de Potasio/genética , Tálamo/citología , Tálamo/efectos de los fármacos
7.
J Neurosci ; 31(28): 10412-23, 2011 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-21753018

RESUMEN

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels generate a pacemaking current, I(h), which regulates neuronal excitability and oscillatory activity in the brain. Although all four HCN isoforms are expressed in the brain, the functional contribution of HCN3 is unknown. Using immunohistochemistry, confocal microscopy, and whole-cell patch-clamp recording techniques, we investigated HCN3 function in thalamic intergeniculate leaflet (IGL) neurons, as HCN3 is reportedly preferentially expressed in these cells. We observed that I(h) recorded from IGL, but not ventral geniculate nucleus, neurons in HCN2(+/+) mice and rats activated slowly and were cAMP insensitive, which are hallmarks of HCN3 channels. We also observed strong immunolabeling for HCN3, with no labeling for HCN1 and HCN4, and only very weak labeling for HCN2. Deletion of HCN2 did not alter I(h) characteristics in mouse IGL neurons. These data together indicate that the HCN3 channel isoform generated I(h) in IGL neurons. Intracellular phosphatidylinositol-4,5-bisphosphate (PIP(2)) shifted I(h) activation to more depolarized potentials and accelerated activation kinetics. Upregulation of HCN3 function by PIP(2) augmented low-threshold burst firing and spontaneous oscillations; conversely, depletion of PIP(2) or pharmacologic block of I(h) resulted in a profound inhibition of excitability. The results indicate that functional expression of HCN3 channels in IGL neurons is crucial for intrinsic excitability and rhythmic burst firing, and PIP(2) serves as a powerful modulator of I(h)-dependent properties via an effect on HCN3 channel gating. Since the IGL is a major input to the suprachiasmatic nucleus, regulation of pacemaking function by PIP(2) in the IGL may influence sleep and circadian rhythms.


Asunto(s)
Canales Catiónicos Regulados por Nucleótidos Cíclicos/metabolismo , Activación del Canal Iónico/fisiología , Neuronas/fisiología , Periodicidad , Fosfoinositido Fosfolipasa C/metabolismo , Tálamo/fisiología , Animales , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización , Potenciales de la Membrana/fisiología , Ratones , Neuronas/metabolismo , Técnicas de Placa-Clamp , Canales de Potasio , Ratas , Tálamo/metabolismo
8.
J Asian Nat Prod Res ; 14(9): 897-905, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22917468

RESUMEN

Puerarin is an isoflavone extracted from Radix Puerariae, a traditional Chinese herb used to treat many diseases such as osteoporosis. In this study, puerarin was shown to stimulate alkaline phosphatase (ALP) activity, type I collagen (Col I) secretion, and mineralized nodules formation of primary osteoblasts. Whereas the estrogen receptor (ER) antagonist ICI 182780 was able to reduce the increase in ALP activity and Col I secretion induced by puerarin. Furthermore, puerarin was shown to elevate levels of phospho-p38 mitogen-activated protein kinase (MAPK) and ß-catenin proteins in a time-dependent manner. Pretreatment of osteoblasts with ICI 182780 can reduce this elevation, whereas pretreatment with p38 MAPK inhibitor SB 203580 did not affect the increase of ß-catenin protein. Meanwhile, intragastric administration of puerarin protected against reduction in bone mineral density and bone mineral content in ovariectomized rats, and improved femur trabecular bone structure. Taken together, ER, p38 MAPK, and Wnt/ß-catenin pathways were involved in puerarin-stimulated osteoblasts differentiation and bone formation.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Colágeno Tipo I/metabolismo , Isoflavonas/farmacología , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Receptores de Estrógenos/efectos de los fármacos , beta Catenina/efectos de los fármacos , beta Catenina/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Animales , Densidad Ósea/efectos de los fármacos , Diferenciación Celular , Colágeno Tipo I/efectos de los fármacos , Estradiol/química , Estradiol/farmacología , Isoflavonas/química , Osteoblastos/efectos de los fármacos , Ratas , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
Science ; 372(6548)2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34140356

RESUMEN

Echolocation is the use of reflected sound to sense features of the environment. Here, we show that soft-furred tree mice (Typhlomys) echolocate based on multiple independent lines of evidence. Behavioral experiments show that these mice can locate and avoid obstacles in darkness using hearing and ultrasonic pulses. The proximal portion of their stylohyal bone fuses with the tympanic bone, a form previously only seen in laryngeally echolocating bats. Further, we found convergence of hearing-related genes across the genome and of the echolocation-related gene prestin between soft-furred tree mice and echolocating mammals. Together, our findings suggest that soft-furred tree mice are capable of echolocation, and thus are a new lineage of echolocating mammals.


Asunto(s)
Ecolocación , Roedores/fisiología , Animales , Evolución Biológica , Huesos/anatomía & histología , Quirópteros/anatomía & histología , Quirópteros/fisiología , Genoma , Audición/genética , Laringe/anatomía & histología , Laringe/fisiología , Mamíferos/anatomía & histología , Mamíferos/genética , Mamíferos/fisiología , Roedores/anatomía & histología , Roedores/genética , Transportadores de Sulfato/genética , Hueso Temporal/anatomía & histología
10.
Zool Res ; 41(6): 670-683, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-32918407

RESUMEN

The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables. Disjunct alpine communities are geographically isolated from one another but experience similar environmental impacts. Isolated homogenous habitats may promote speciation but constrain functional trait variation. In this study, we examined the hypothesis that dispersal limitation promotes taxonomic divergence, whereas habitat similarity in alpine mountains leads to functional convergence. We performed standardized field investigation to sample non-volant small mammals from 18 prominent alpine sites in the Three Parallel Rivers area. We estimated indices quantifying taxonomic and functional alpha- and beta-diversity, as well as beta-diversity components. We then assessed the respective importance of geographical and environmental predictors in explaining taxonomic and functional compositions. No evidence was found to show that species were more functionally similar than expected in local assemblages. However, the taxonomic turnover components were higher than functional ones (0.471±0.230 vs. 0.243±0.215), with nestedness components showing the opposite pattern (0.063±0.054 vs. 0.269±0.225). This indicated that differences in taxonomic compositions between sites occurred from replacement of functionally similar species. Geographical barriers were the key factor influencing both taxonomic total dissimilarity and turnover components, whereas functional beta-diversity was primarily explained by climatic factors such as minimum temperature of the coldest month. Our findings provide empirical evidence that taxonomic and functional diversity patterns can be independently driven by different ecological processes. Our results point to the importance of clarifying different components of beta-diversity to understand the underlying mechanisms of community assembly. These results also shed light on the assembly rules and ecological processes of terrestrial mammal communities in extreme environments.


Asunto(s)
Genoma Mitocondrial , Presbytini/genética , Distribución Animal , Animales , Asia , ADN/genética , Heces/química , Femenino , Masculino , Filogenia , Especificidad de la Especie
11.
Can J Cardiol ; 36(9): 1467-1473, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32492399

RESUMEN

BACKGROUND: Pediatric hypertension is typically defined as blood pressure ≥ sex-, age-, and height-specific 95th percentile (high) cutoffs. Given the number of strata, there are hundreds of cutoffs for defining elevated and high blood pressure that make it cumbersome to use in clinical practice. This study aimed to evaluate the utility of the static cutoffs for pediatric hypertension (120/80 mm Hg for children and 130/80 mm Hg for adolescents) in determining high carotid intimamedia thickness (cIMT) in children and adolescents. METHODS: Data were from 6 population-based cross-sectional studies in Brazil, China, Greece, Italy, Spain, and the United Kingdom. A total of 4280 children and adolescents, aged 6 to 17 years, were included. High cIMT was defined as cIMT ≥ sex-, age- and cohort-specific 90th percentile cutoffs. RESULTS: Compared with normal blood pressure, hypertension defined using the percentile-based cutoffs from 2017 American Academy of Pediatrics guideline, and the static cutoffs were associated with similar higher odds for high cIMT (percentile-based cutoffs: odds ratio [OR], 1.46, 95% confidence interval [CI], 1.15-1.86; static cutoffs: OR, 1.65, 95% CI, 1.25-2.17), after adjustment for sex, age, race/ethnicity, body mass index, high-density lipoprotein-cholesterol, triglyceride, and fasting blood glucose. The similar utility of 2 definitions in determining high cIMT was further confirmed by area under the receiver operating characteristic curve and net reclassification improvement methods (P for difference > 0.05). CONCLUSION: Static cutoffs (120/80 mm Hg for children, 130/80 mm Hg for adolescents) performed similarly compared with percentile-based cutoffs in determining high cIMT, supporting the use of static cutoffs in identifying pediatric hypertension in clinical practice.


Asunto(s)
Presión Sanguínea/fisiología , Índice de Masa Corporal , Grosor Intima-Media Carotídeo , Hipertensión/diagnóstico , Obesidad Infantil/complicaciones , Adolescente , Niño , Estudios Transversales , Femenino , Salud Global , Humanos , Hipertensión/etiología , Hipertensión/fisiopatología , Masculino , Morbilidad/tendencias , Obesidad Infantil/epidemiología , Factores de Riesgo
12.
J Hypertens ; 38(4): 618-624, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31790055

RESUMEN

OBJECTIVE: The clinical utility of screening for pediatric metabolic syndrome (MetS) in children and adolescents is still controversial. We examined the performance of pediatric MetS vs. clustering of cardiovascular risk factors (which are the components of MetS) for predicting high carotid intima-media thickness (cIMT) in children and adolescents. METHODS: Participants included 2427 children and adolescents aged 6-17 years from population-based studies in three countries (Brazil, China and Italy). Pediatric MetS was defined using either the modified National Cholesterol Education Program Adult Treatment Panel III criteria or the modified International Diabetes Federation criteria. Clustering of cardiovascular risk factors was calculated as the sum of five components of MetS (i.e. central obesity, elevated blood pressure, elevated triglycerides, reduced HDL-cholesterol and elevated fasting blood glucose). High cIMT was defined as cIMT at least 95th percentile values for sex and age developed from European children. RESULTS: Presence of one, two or at least three cardiovascular risk factors (using the National Cholesterol Education Program Adult Treatment Panel III criteria), as compared with none, was associated with gradually increasing odds of high cIMT [odds ratios (95% confidence intervals): 1.60 (1.29-1.99), 2.89 (2.21-3.78) and 4.24 (2.81-6.39), respectively]. High cIMT was also associated with presence (vs. absence) of MetS (odds ratio = 2.88, 95% confidence interval = 1.95-4.26). However, clustering of cardiovascular risk factors predicted high cIMT markedly better than MetS (area under the curve of 0.66 vs. 0.54, respectively). Findings were similar using the International Diabetes Federation criteria for pediatric MetS. CONCLUSION: In children and adolescents, a graded score based on five cardiovascular risk factors (used to define MetS) predicted high cIMT markedly better than MetS. These findings do not support the clinical utility of MetS for screening youth at increased cardiovascular risk, as expressed in this study by high cIMT.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Grosor Intima-Media Carotídeo , Síndrome Metabólico/complicaciones , Obesidad Infantil/complicaciones , Adolescente , Glucemia/metabolismo , Brasil , Enfermedades Cardiovasculares/sangre , Niño , China , Colesterol/sangre , Análisis por Conglomerados , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Hipertensión/complicaciones , Italia , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/fisiopatología , Obesidad Infantil/fisiopatología , Triglicéridos/sangre
13.
Neuropharmacology ; 56(2): 438-47, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18948126

RESUMEN

GABAergic neurons in the reticular thalamic nucleus (RTN) synapse onto thalamocortical neurons in the ventrobasal (VB) thalamus, and this reticulo-thalamocortical pathway is considered an anatomic target for general anesthetic-induced unconsciousness. A mutant mouse was engineered to harbor two amino acid substitutions (S270H, L277A) in the GABA(A) receptor (GABA(A)-R) alpha1 subunit; this mutation abolished sensitivity to the volatile anesthetic isoflurane in recombinant GABA(A)-Rs, and reduced in vivo sensitivity to isoflurane in the loss-of-righting-reflex assay. We examined the effects of the double mutation on GABA(A)-R-mediated synaptic currents and isoflurane sensitivity by recording from thalamic neurons in brain slices. The double mutation accelerated the decay, and decreased the (1/2) width of, evoked inhibitory postsynaptic currents (eIPSCs) in VB neurons and attenuated isoflurane-induced prolongation of the eIPSC. The hypnotic zolpidem, a selective modulator of GABA(A)-Rs containing the alpha1 subunit, prolonged eIPSC duration regardless of genotype, indicating that mutant mice incorporate alpha1 subunit-containing GABA(A)-Rs into synapses. In RTN neurons, which lack the alpha1 subunit, eIPSC duration was longer than in VB, regardless of genotype. Isoflurane reduced the efficacy of GABAergic transmission from RTN to VB, independent of genotype, suggesting a presynaptic action in RTN neurons. Consistent with this observation, isoflurane inhibited both tonic action potential and rebound burst firing in the presence of GABA(A)-R blockade. The suppressed excitability in RTN neurons is likely mediated by isoflurane-enhanced Ba(2+)-sensitive, but 4-aminopyridine-insenstive, potassium conductances. We conclude that isoflurane enhances inhibition of thalamic neurons in VB via GABA(A)-R-dependent, but in RTN via GABA(A)-R-independent, mechanisms.


Asunto(s)
Anestésicos por Inhalación/farmacología , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Isoflurano/farmacología , Neuronas/efectos de los fármacos , Tálamo/citología , Ácido gamma-Aminobutírico/metabolismo , 4-Aminopiridina/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/genética , Alanina/genética , Animales , Biofisica , Relación Dosis-Respuesta a Droga , Agonistas del GABA/farmacología , Histidina/genética , Potenciales Postsinápticos Inhibidores/genética , Potenciales Postsinápticos Inhibidores/fisiología , Leucina/genética , Ratones , Ratones Transgénicos , Mutación , Inhibición Neural/efectos de los fármacos , Inhibición Neural/genética , Técnicas de Placa-Clamp/métodos , Bloqueadores de los Canales de Potasio/farmacología , Piridazinas/farmacología , Receptores de GABA-A/genética , Serina/genética , Factores de Tiempo
14.
Mol Med Rep ; 19(4): 2463-2470, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30720087

RESUMEN

Differential proteomic technology was used to identify urine proteomic profile of gestational hypertension and preeclampsia. Urine samples were collected from 10 patients with gestational hypertension, 10 patients with mild preeclampsia, 10 patients with severe preeclampsia and 10 normal pregnancies and analyzed by 2­D difference gel electrophoresis, then matrix assisted laser desorption ionization mass spectrometry was used to identify differential proteins. Subsequently, ELISA was used to verify the content variation of the identified proteins in 200 urine samples. In total, 30 differential proteins were identified. For prostaglandin­H2 D­isomerase (L­PGDS), perlecan and other 15 proteins, the contents in patients with gestational hypertension were higher than that of normal pregnancies, but lower in mild and severe preeclampsia. By contrast, serum albumin and α­1­antitrypsin was lower in samples from patients with gestational hypertension and higher in patients with mild and severe preeclampsia compared with normal pregnancies. ELISA verified that the urinary concentration of L­PGDS and perlecan were significantly lower in patients with preeclampsia than in normal pregnancies (P<0.05). Urine proteomics is a useful tool to identify potential biomarkers to distinguish between different types of hypertensive disorders in pregnancy. L­PGDS and perlecan could potentially be used as markers to reflect the state of renal function, and may participate in the genesis and development of renal injury during preeclampsia.


Asunto(s)
Biomarcadores , Hipertensión Inducida en el Embarazo/orina , Preeclampsia/orina , Adulto , Estudios de Casos y Controles , Electroforesis en Gel Bidimensional , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Embarazo , Proteoma , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
Zool Res ; 40(1): 53-60, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30581186

RESUMEN

The distribution of small mammals in mountainous environments across different elevations can provide important information on the effects of climate change on the dispersal of species. However, few studies conducted on Afromontane ecosystems have compared the altitudinal patterns of small mammal diversity. We investigated the species diversity and abundance of non-volant small mammals (hereafter 'small mammals') on Mt. Kenya, the second tallest mountain in Africa, using a standard sampling scheme. Nine sampling transects were established at intervals of 200 m on the eastern (Chogoria) and western (Sirimon) slopes. A total of 1 905 individuals representing 25 species of small mammals were trapped after 12 240 trap-nights. Abundance was highest at mid-elevations on both slopes. However, species richness and distribution patterns differed between the two slopes. More species were recorded on Chogoria (24) than on Sirimon (17). On Chogoria, species richness was higher at mid-high elevations, with a peak at mid-elevation (2 800 m a.s.l.), whereas species richness showed little variation on the Sirimon slope. These results indicate that patterns of species diversity can differ between slopes on the same mountain. In addition, we extensively reviewed literature on Mt. Kenya's mammals and compiled a comprehensive checklist of 76 mammalian species. However, additional research is required to improve our understanding of small mammal diversity in mountain habitats in Africa.


Asunto(s)
Distribución Animal , Biodiversidad , Mamíferos , Altitud , Animales , Kenia , Densidad de Población
16.
Diabetes Care ; 42(1): 119-125, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30420475

RESUMEN

OBJECTIVE: It has been argued that metabolically healthy obesity (MHO) does not increase cardiovascular disease (CVD) risk. This study examines the association of MHO with carotid intima-media thickness (cIMT), a proxy of CVD risk, in children and adolescents. RESEARCH DESIGN AND METHODS: Data were available for 3,497 children and adolescents aged 6-17 years from five population-based cross-sectional studies in Brazil, China, Greece, Italy, and Spain. Weight status categories (normal, overweight, and obese) were defined using BMI cutoffs from the International Obesity Task Force. Metabolic status (defined as "healthy" [no risk factors] or "unhealthy" [one or more risk factors]) was based on four CVD risk factors: elevated blood pressure, elevated triglyceride levels, reduced HDL cholesterol, and elevated fasting glucose. High cIMT was defined as cIMT ≥90th percentile for sex, age, and study population. Logistic regression model was used to examine the association of weight and metabolic status with high cIMT, with adjustment for sex, age, race/ethnicity, and study center. RESULTS: In comparison with metabolically healthy normal weight, odds ratios (ORs) for high cIMT were 2.29 (95% CI 1.58-3.32) for metabolically healthy overweight and 3.91 (2.46-6.21) for MHO. ORs for high cIMT were 1.44 (1.03-2.02) for unhealthy normal weight, 3.49 (2.51-4.85) for unhealthy overweight, and 6.96 (5.05-9.61) for unhealthy obesity. CONCLUSIONS: Among children and adolescents, cIMT was higher for both MHO and metabolically healthy overweight compared with metabolically healthy normal weight. Our findings reinforce the need for weight control in children and adolescents irrespective of their metabolic status.


Asunto(s)
Grosor Intima-Media Carotídeo , Obesidad Metabólica Benigna/epidemiología , Sobrepeso/epidemiología , Obesidad Infantil/epidemiología , Adolescente , Presión Sanguínea , Brasil , Niño , China , Estudios Transversales , Femenino , Estudios de Seguimiento , Grecia , Estado de Salud , Humanos , Italia , Modelos Logísticos , Masculino , Obesidad Metabólica Benigna/sangre , Sobrepeso/sangre , Obesidad Infantil/sangre , Prevalencia , Factores de Riesgo , España
17.
J Neurosci ; 27(32): 8719-32, 2007 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-17687049

RESUMEN

Hyperpolarization activated cyclic nucleotide (HCN) gated channels conduct a current, I(h); how I(h) influences excitability and spike firing depends primarily on channel distribution in subcellular compartments. For example, dendritic expression of HCN1 normalizes somatic voltage responses and spike output in hippocampal and cortical neurons. We reported previously that HCN2 is predominantly expressed in dendritic spines in reticular thalamic nucleus (RTN) neurons, but the functional impact of such nonsomatic HCN2 expression remains unknown. We examined the role of HCN2 expression in regulating RTN excitability and GABAergic output from RTN to thalamocortical relay neurons using wild-type and HCN2 knock-out mice. Pharmacological blockade of I(h) significantly increased spike firing in RTN neurons and large spontaneous IPSC frequency in relay neurons; conversely, pharmacological enhancement of HCN channel function decreased spontaneous IPSC frequency. HCN2 deletion abolished I(h) in RTN neurons and significantly decreased sensitivity to 8-bromo-cAMP and lamotrigine. Recapitulating the effects of I(h) block, HCN2 deletion increased both temporal summation of EPSPs in RTN neurons as well as GABAergic output to postsynaptic relay neurons. The enhanced excitability of RTN neurons after I(h) block required activation of ionotropic glutamate receptors; consistent with this was the colocalization of HCN2 and glutamate receptor 4 subunit immunoreactivities in dendritic spines of RTN neurons. The results indicate that, in mouse RTN neurons, HCN2 is the primary functional isoform underlying I(h) and expression of HCN2 constrains excitatory synaptic integration.


Asunto(s)
Dendritas/fisiología , Canales Iónicos/fisiología , Receptores de Glutamato/fisiología , Formación Reticular/fisiología , Tálamo/fisiología , Animales , Potenciales Postsinápticos Excitadores/fisiología , Ácido Glutámico/fisiología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización , Ratones , Ratones Noqueados , Neuronas/fisiología , Canales de Potasio , Formación Reticular/citología , Ácido gamma-Aminobutírico/fisiología
18.
Zool Res ; 39(5): 321-334, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-29976842

RESUMEN

Blarinellini is a tribe of soricine shrews comprised of nine fossil genera and one extant genus. Blarinelline shrews were once widely distributed throughout Eurasia and North America, though only members of the Asiatic short-tailed shrew genus Blarinella currently persist (mostly in southwestern China and adjacent areas). Only three forms of Blarinella have been recognized as either species or subspecies. However, recent molecular studies indicated a strikingly deep divergence within the genus, implying the existence of a distinct genus-level lineage. We sequenced the complete mitochondrial genomes and one nuclear gene of three Asiatic short-tailed and two North American shrews and analyzed them morphometrically and morphologically. Our molecular analyses revealed that specimens ascribed to B. griselda formed two deeply diverged lineages, one a close relative to B. quadraticauda, whereas the other - comprised of topotype specimens from southern Gansu - diverged from other Blarinella in the middle Miocene (ca. 18.2 million years ago (Ma), 95% confidence interval=13.4-23.6 Ma). Although the skulls were similarly shaped in both lineages, we observed several diagnostic characteristics, including the shape of the upper P4. In consideration of the molecular and morphological evidence, we recognize B. griselda as the sole species of a new genus, namely, Pantherina gen. nov. Interestingly, some characteristics of Pantherina griselda are more similar to fossil genera, suggesting it represents an evolutionarily more primitive form than Blarinella. Recognition of this new genus sheds light on the systematics and evolutionary history of the tribe Blarinellini throughout Eurasia and North America.


Asunto(s)
Musarañas/anatomía & histología , Animales , Evolución Biológica , China , Mitocondrias/genética , América del Norte , Análisis de Secuencia de ADN , Musarañas/clasificación , Musarañas/genética , Cráneo/anatomía & histología
19.
Zool Res ; 39(5): 356-363, 2018 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-29616678

RESUMEN

Gibbons and siamangs (Hylobatidae) are well-known for their rapid chromosomal evolution, which has resulted in high speciation rate within the family. On the other hand, distinct karyotypes do not prevent speciation, allowing interbreeding between individuals in captivity, and the unwanted hybrids are ethically problematic as all gibbon species are endangered or critically endangered. Thus, accurate species identification is crucial for captive breeding, particularly in China where studbooks are unavailable. Identification based on external morphology is difficult, especially for hybrids, because species are usually similar in appearance. In this study, we employed G-banding karyotyping and fluorescence in situ hybridization (FISH) as well as a PCR-based approach to examine karyotypic characteristics and identify crested gibbons of the genus Nomascus from zoos and nature reserves in China. We characterized and identified five karyotypes from 21 individuals of Nomascus. Using karyotypes and mitochondrial and nuclear genes, we identified three purebred species and three hybrids, including one F2 hybrid between N. gabriellae and N. siki. Our results also supported that N. leucogenys and N. siki shared the same inversion on chromosome 7, which resolves arguments from previous studies. Our results demonstrated that both karyotyping and DNA-based approaches were suitable for identifying purebred species, though neither was ideal for hybrid identification. The advantages and disadvantages of both approaches are discussed. Our results further highlight the importance of animal ethics and welfare, which are critical for endangered species in captivity.


Asunto(s)
Hylobates/genética , Animales , Animales de Zoológico , Núcleo Celular/genética , China , Especies en Peligro de Extinción , Genes/genética , Hylobates/clasificación , Hibridación Fluorescente in Situ , Cariotipo , Cariotipificación , Mitocondrias/genética , Reacción en Cadena de la Polimerasa
20.
Radiat Oncol ; 12(1): 6, 2017 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-28069017

RESUMEN

BACKGROUND: Dose escalation of SBRT for locally advanced pancreatic cancer patients had been reported in several studies in one or three fractions, and phase I protocol was developed to investigate the maximum tolerated dose with CyberKnife for locally advanced unresectable pancreatic cancer patients in five fractions. METHODS: The study is designed as a mono-center phase I study. The primary endpoint is to determine the maximum tolerated dose by frequency of III/IV GI (gastrointestinal) toxicity. Adverse events (AE) according to Common Toxicity Criteria (CTC) version 4. Doses of 7 Gy, 7.5 Gy, 8 Gy, 8.5 Gy, 9 Gy, 9.5Gy x 5 respectively would be delivered while meeting with normal tissue constraints. A minimum of three patients will be included for each dosage level. And an interval is 4 weeks from the first patient treatment to the next patient treatment at each dose level. The maximal tolerated dose will be defined as the dose for which at least two patients in three, or at least three patients in nine, will present with a limiting toxicity. DISCUSSION: Since the dose and fractions of SBRT treatment for locally advanced pancreatic cancer patients are still unknown, we propose to conduct a Phase I study determining the maximum tolerated dose of CyberKnife SBRT for the treatment of locally advanced pancreatic tumor based on a 5 fractions treatment regimen. This trial protocol has been approved by the Ethics committee of Changhai hospital. The ethics number is 2016-030-01. TRIAL REGISTRATION: Clinical trials number: NCT02716207 . Date of registration: 20 March 2016.


Asunto(s)
Neoplasias Pancreáticas/radioterapia , Radiocirugia/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Dosificación Radioterapéutica , Proyectos de Investigación
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