Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 192
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Blood ; 142(1): 106-118, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37053547

RESUMO

Inflammation leads to functional iron deficiency by increasing the expression of the hepatic iron regulatory peptide hepcidin. Inflammation also stimulates fibroblast growth factor 23 (FGF23) production by increasing both Fgf23 transcription and FGF23 cleavage, which paradoxically leads to excess in C-terminal FGF23 peptides (Cter-FGF23), rather than intact FGF23 (iFGF23) hormone. We determined that the major source of Cter-FGF23 is osteocytes and investigated whether Cter-FGF23 peptides play a direct role in the regulation of hepcidin and iron metabolism in response to acute inflammation. Mice harboring an osteocyte-specific deletion of Fgf23 showed a ∼90% reduction in Cter-FGF23 levels during acute inflammation. Reduction in Cter-FGF23 led to a further decrease in circulating iron in inflamed mice owing to excessive hepcidin production. We observed similar results in mice showing impaired FGF23 cleavage owing to osteocyte-specific deletion of Furin. We next showed that Cter-FGF23 peptides bind members of the bone morphogenetic protein (BMP) family, BMP2 and BMP9, which are established inducers of hepcidin. Coadministration of Cter-FGF23 and BMP2 or BMP9 prevented the increase in Hamp messenger RNA and circulating hepcidin levels induced by BMP2/9, resulting in normal serum iron levels. Finally, injection of Cter-FGF23 in inflamed Fgf23KO mice and genetic overexpression of Cter-Fgf23 in wild type mice also resulted in lower hepcidin and higher circulating iron levels. In conclusion, during inflammation, bone is the major source of Cter-FGF23 secretion, and independently of iFGF23, Cter-FGF23 reduces BMP-induced hepcidin secretion in the liver.


Assuntos
Fatores de Crescimento de Fibroblastos , Hepcidinas , Ferro , Animais , Camundongos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Inflamação/genética , Peptídeos
2.
Nat Chem Biol ; 18(3): 272-280, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34949836

RESUMO

Class B G protein-coupled receptors (GPCRs) are notoriously difficult to target by small molecules because their large orthosteric peptide-binding pocket embedded deep within the transmembrane domain limits the identification and development of nonpeptide small molecule ligands. Using the parathyroid hormone type 1 receptor (PTHR) as a prototypic class B GPCR target, and a combination of molecular dynamics simulations and elastic network model-based methods, we demonstrate that PTHR druggability can be effectively addressed. Here we found a key mechanical site that modulates the collective dynamics of the receptor and used this ensemble of PTHR conformers to identify selective small molecules with strong negative allosteric and biased properties for PTHR signaling in cell and PTH actions in vivo. This study provides a computational pipeline to detect precise druggable sites and identify allosteric modulators of PTHR signaling that could be extended to GPCRs to expedite discoveries of small molecules as novel therapeutic candidates.


Assuntos
Receptor Tipo 1 de Hormônio Paratireóideo , Receptores Acoplados a Proteínas G , Ligantes , Simulação de Dinâmica Molecular , Transdução de Sinais
3.
Artigo em Inglês | MEDLINE | ID: mdl-38916769

RESUMO

BACKGROUND: Previous research has linked attention deficit hyperactivity disorder (ADHD) with an increased risk of all-cause mortality, primarily owing to unnatural causes such as accidents and suicides. This increase may be attributable to the co-occurrence of major psychiatric disorders, including schizophrenia (SCZ), bipolar disorder (BD), major depressive disorder (MDD), autism spectrum disorder (ASD), anxiety disorders, substance use disorders (SUDs), and personality disorders (PDs). This study examined the all-cause and specific-cause mortality rates in individuals with ADHD and the influence of psychiatric comorbidities. METHODS: Between 2003 and 2017, 1.17 million individuals were enrolled in the study, of which 233,886 received a diagnosis of ADHD from the Taiwan's National Health Insurance Research Database. A 1:4 sex- and birth year-matched control group without ADHD was also included. Hazard ratios (HRs) for mortality rates were estimated between groups after adjusting for demographic data. RESULTS: During the follow-up period, 781 individuals with ADHD died. The HR for all-cause mortality was 1.45 (95% confidence interval [CI]: 1.30-1.61), largely owing to unnatural causes, particularly suicide. Suicide rates were particularly high in individuals with ADHD and psychiatric comorbidities: the HRs for suicide were 47.06 in ADHD with SUDs (95% CI: 6.12-361.99), 32.02 in ADHD with SCZ (7.99-128.29), 23.60 in ADHD with PDs (7.27-76.66), 10.11 in ADHD with anxiety disorders (5.74-17.82), 9.30 in ADHD with BD (4.48-19.33), 8.36 in ADHD with MDD (5.66-12.35), and 6.42 in ADHD with ASD (1.83-22.53) relative to ADHD only. DISCUSSION: ADHD was associated with increased mortality rates, primarily owing to suicide. The presence of major psychiatric comorbidities was associated with a further increase in suicide mortality risk.

4.
Br J Psychiatry ; 223(4): 465-470, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37350338

RESUMO

BACKGROUND: Evidence suggests a familial coaggregation of major psychiatric disorders, including schizophrenia, bipolar disorder, major depression (MDD), autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). Those disorders are further related to suicide and accidental death. However, whether death by suicide may coaggregate with accidental death and major psychiatric disorders within families remains unclear. AIMS: To clarify the familial coaggregation of deaths by suicide with accidental death and five major psychiatric disorders. METHOD: Using a database linked to the entire Taiwanese population, 68 214 first-degree relatives of individuals who died by suicide between 2003 and 2017 and 272 856 age- and gender-matched controls were assessed for the risks of death by suicide, accidental death and major psychiatric disorders. RESULTS: A Poisson regression model showed that the first-degree relatives of individuals who died by suicide were more likely to die by suicide (relative risk RR = 4.61, 95% CI 4.02-5.29) or accident (RR = 1.62, 95% CI 1.43-1.84) or to be diagnosed with schizophrenia (RR = 1.53, 95% CI 1.40-1.66), bipolar disorder (RR = 1.99, 95% CI 1.83-2.16), MDD (RR = 1.98, 95% CI 1.89-2.08) or ADHD (RR = 1.34, 95% CI 1.24-1.44). CONCLUSIONS: Our findings identified a familial coaggregation of death by suicide with accidental death, schizophrenia, major affective disorders and ADHD. Further studies would be required to elucidate the pathological mechanisms underlying this coaggregation.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Bipolar , Transtorno Depressivo Maior , Suicídio , Humanos , Transtorno Bipolar/genética , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética
5.
Eur Arch Psychiatry Clin Neurosci ; 273(7): 1433-1442, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36484844

RESUMO

The dorsomedial prefrontal cortex (DMPFC) plays a pivotal role in depression and anxiosomatic symptom modulation. However, DMPFC stimulation using a double-cone coil has demonstrated inconsistent results for antidepressant efficacy. No study thus far has investigated the antidepressant and anti-anxiosomatic effects of prolonged intermittent theta-burst stimulation (piTBS) bilaterally over DMPFC. Furthermore, head-to-head comparisons of antidepressant effects between standard iTBS and piTBS warrant investigation. This double-blind, randomized, sham-controlled trial recruited 34 patients with highly treatment-resistant depression (TRD) unresponsive to antidepressants and standard repetitive transcranial magnetic stimulation (rTMS)/piTBS. These patients were randomly assigned to one of three monotherapy groups (standard iTBS, piTBS, or sham), with treatment administered bilaterally over the DMPFC twice per day for 3 weeks. The primary outcome was the overall changes of 17-item Hamilton Depression Rating Scale (HDRS-17) over 3-weeks intervention. The changes in Depression and Somatic Symptoms Scale (DSSS) as the secondary outcome and the anxiosomatic cluster symptoms as rated by HDRS-17 as the post-hoc outcome were measured. Multivariable generalized estimating equation analysis was performed. Although no differences in overall HDRS-17 changes between three groups were found, the antidepressant efficacy based on DSSS was higher in piTBS than in iTBS and sham at week 3 (group effect,p = 0.003, post-hoc: piTBS > iTBS, p = 0.002; piTBS > sham, p = 0.038). In post-hoc analyses, piTBS had more alleviation in anxiosomatic symptoms than iTBS (group effect, p = 0.002; post-hoc, p = 0.001). This first randomized sham-controlled study directly compared piTBS and iTBS targeting the DMPFC using a figure-of-8 coil and found piTBS may fail to demonstrate a significant antidepressant effect on overall depressive symptoms, but piTBS seems superior in alleviating anxiosomatic symptoms, even in depressed patients with high treatment resistance. This Trial registration (Registration number: NCT04037592). URL: https://clinicaltrials.gov/ct2/show/NCT04037592 .


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Estimulação Magnética Transcraniana/métodos , Depressão/terapia , Projetos Piloto , Resultado do Tratamento , Córtex Pré-Frontal/fisiologia , Antidepressivos/uso terapêutico , Método Duplo-Cego
6.
J Am Soc Nephrol ; 33(7): 1323-1340, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35581010

RESUMO

BACKGROUND: Impaired mineral ion metabolism is a hallmark of CKD-metabolic bone disorder. It can lead to pathologic vascular calcification and is associated with an increased risk of cardiovascular mortality. Loss of calcium-sensing receptor (CaSR) expression in vascular smooth muscle cells exacerbates vascular calcification in vitro. Conversely, vascular calcification can be reduced by calcimimetics, which function as allosteric activators of CaSR. METHODS: To determine the role of the CaSR in vascular calcification, we characterized mice with targeted Casr gene knockout in vascular smooth muscle cells ( SM22α CaSR Δflox/Δflox ). RESULTS: Vascular smooth muscle cells cultured from the knockout (KO) mice calcified more readily than those from control (wild-type) mice in vitro. However, mice did not show ectopic calcifications in vivo but they did display a profound mineral ion imbalance. Specifically, KO mice exhibited hypercalcemia, hypercalciuria, hyperphosphaturia, and osteopenia, with elevated circulating fibroblast growth factor 23 (FGF23), calcitriol (1,25-D3), and parathyroid hormone levels. Renal tubular α-Klotho protein expression was increased in KO mice but vascular α-Klotho protein expression was not. Altered CaSR expression in the kidney or the parathyroid glands could not account for the observed phenotype of the KO mice. CONCLUSIONS: These results suggest that, in addition to CaSR's established role in the parathyroid-kidney-bone axis, expression of CaSR in vascular smooth muscle cells directly contributes to total body mineral ion homeostasis.


Assuntos
Receptores de Detecção de Cálcio , Calcificação Vascular , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/metabolismo , Proteínas Klotho , Camundongos , Camundongos Knockout , Minerais/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismo , Calcificação Vascular/etiologia
7.
Medicina (Kaunas) ; 59(3)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36984465

RESUMO

Coronavirus disease 2019 (COVID-19) remains a global pandemic. Early warning scores (EWS) are used to identify potential clinical deterioration, and this study evaluated the ability of the Rapid Emergency Medicine score (REMS), National Early Warning Score (NEWS), and Modified EWS (MEWS) to predict in-hospital mortality in COVID-19 patients. This study retrospectively analyzed data from COVID-19 patients who presented to the emergency department and were hospitalized between 1 May and 31 July 2021. The area under curve (AUC) was calculated to compare predictive performance of the three EWS. Data from 306 COVID-19 patients (61 ± 15 years, 53% male) were included for analysis. REMS had the highest AUC for in-hospital mortality (AUC: 0.773, 95% CI: 0.69-0.85), followed by NEWS (AUC: 0.730, 95% CI: 0.64-0.82) and MEWS (AUC: 0.695, 95% CI: 0.60-0.79). The optimal cut-off value for REMS was 6.5 (sensitivity: 71.4%; specificity: 76.3%), with positive and negative predictive values of 27.9% and 95.4%, respectively. Computing REMS for COVID-19 patients who present to the emergency department can help identify those at risk of in-hospital mortality and facilitate early intervention, which can lead to better patient outcomes.


Assuntos
COVID-19 , Escore de Alerta Precoce , Humanos , Masculino , Feminino , Estudos Retrospectivos , Mortalidade Hospitalar , Taiwan/epidemiologia , Centros de Atenção Terciária , Serviço Hospitalar de Emergência , Curva ROC
8.
J Infect Dis ; 226(1): 38-48, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34962571

RESUMO

BACKGROUND: Immune reconstitution bone loss (IRBL) is a common side-effect of antiretroviral therapy (ART) in people with human immunodeficiency virus (PWH). Immune reconstitution bone loss acts through CD4+ T-cell/immune reconstitution-induced inflammation and is independent of antiviral regimen. Immune reconstitution bone loss may contribute to the high rate of bone fracture in PWH, a cause of significant morbidity and mortality. Although IRBL is transient, it remains unclear whether bone recovers, or whether it is permanently denuded and further compounds bone loss associated with natural aging. METHODS: We used a validated IRBL mouse model involving T-cell reconstitution of immunocompromised mice. Mice underwent cross-sectional bone phenotyping of femur and/or vertebrae between 6 and 20 months of age by microcomputed tomography (µCT) and quantitative bone histomorphometry. CD4+ T cells were purified at 20 months to quantify osteoclastogenic/inflammatory cytokine expression. RESULTS: Although cortical IRBL in young animals recovered with time, trabecular bone loss was permanent and exacerbated skeletal decline associated with natural aging. At 20 months of age, reconstituted CD4+ T cells express enhanced osteoclastogenic cytokines including RANKL, interleukin (IL)-1ß, IL-17A, and tumor necrosis factor-α, consistent with elevated osteoclast numbers. CONCLUSIONS: Immune reconstitution bone loss in the trabecular compartment is permanent and further exacerbates bone loss due to natural aging. If validated in humans, interventions to limit IRBL may be important to prevent fractures in aging PWH.


Assuntos
Infecções por HIV , Reconstituição Imune , Envelhecimento , Animais , Linfócitos T CD4-Positivos , Citocinas/metabolismo , Infecções por HIV/complicações , Humanos , Camundongos , Microtomografia por Raio-X
9.
Pediatr Res ; 91(6): 1391-1398, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33958714

RESUMO

BACKGROUND: Continuous positive airway pressure (CPAP) in preterm infants is initially beneficial, but animal models suggest longer term detrimental airway effects towards asthma. We used a neonatal CPAP mouse model and human fetal airway smooth muscle (ASM) to investigate the role of extracellular calcium-sensing receptor (CaSR) in these effects. METHODS: Newborn wild type and smooth muscle-specific CaSR-/- mice were given CPAP for 7 days via a custom device (mimicking CPAP in premature infants), and recovered in normoxia for another 14 days (representing infants at 3-4 years). Airway reactivity was tested using lung slices, and airway CaSR quantified. Role of CaSR was tested using NPS2143 (inhibitor) or siRNA in WT mice. Fetal ASM cells stretched cyclically with/without static stretch mimicking breathing and CPAP were analyzed for intracellular Ca2+ ([Ca2+]i) responses, role of CaSR, and signaling cascades. RESULTS: CPAP increased airway reactivity in WT but not CaSR-/- mice, increasing ASM CaSR. NPS2143 or CaSR siRNA reversed CPAP effects in WT mice. CPAP increased fetal ASM [Ca2+]I, blocked by NPS2143, and increased ERK1/2 and RhoA suggesting two mechanisms by which stretch increases CaSR. CONCLUSIONS: These data implicate CaSR in CPAP effects on airway function with implications for wheezing in former preterm infants. IMPACT: Neonatal CPAP increases airway reactivity to bronchoconstrictor agonist. CPAP increases smooth muscle expression of the extracellular calcium-sensing receptor (CaSR). Inhibition or absence of CaSR blunts CPAP effects on contractility. These data suggest a causal/contributory role for CaSR in stretch effects on the developing airway. These data may impact clinical recognition of the ways that CPAP may contribute to wheezing disorders of former preterm infants.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Receptores de Detecção de Cálcio , Animais , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Camundongos , Camundongos Knockout , RNA Interferente Pequeno , Receptores de Detecção de Cálcio/genética , Sons Respiratórios
10.
J Biomed Inform ; 133: 104171, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35995106

RESUMO

The emergency department (ED) plays a very significant role in the hospital. Owing to the rising number of ED visits, medical service points, and ED market, overcrowding of EDs has become serious worldwide. Overcrowding has long been recognized as a vital issue that increases the risk to patients and negative emotions of medical personnel and impacts hospital cost management. For the past years, many researchers have been applying artificial intelligence to reduce crowding situations in the ED. Nevertheless, the datasets in ED hospital admission are naturally inherent with the high-class imbalance in the real world. Previous studies have not considered the imbalance of the datasets, particularly addressing the imbalance. This study purposes to develop a natural language processing model of a deep neural network with an attention mechanism to solve the imbalanced problem in ED admission. The proposed framework is used for predicting hospital admission so that the hospitals can arrange beds early and solve the problem of congestion in the ED. Furthermore, the study compares a variety of methods and obtains the best composition that has the best performance for forecasting hospitalization in ED. The study used the data from a specific hospital in Taiwan as an empirical study. The experimental result demonstrates that almost all imbalanced methods can improve the model's performance. In addition, the natural language processing model of Bi-directional Long Short-Term Memory with attention mechanism has the best results in all-natural language processing methods.


Assuntos
Inteligência Artificial , Processamento de Linguagem Natural , Serviço Hospitalar de Emergência , Hospitalização , Humanos , Redes Neurais de Computação
11.
Int J Sports Med ; 42(11): 1035-1042, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33690866

RESUMO

Our study aimed to (i) utilize novel electrical cardiometry and observe acute changes in cardiac biomarkers among 24-h and 48-h ultra-marathoners, and (ii) examine whether alterations in cardiac responses were associated with the average running speed of these participants. Twenty-four 24-h and sixteen 48-h ultra-marathoners were recruited. Electrical cardiometry in the 2 groups showed significant post-race drops in systolic pressure (24-h: p=0.001; 48-h: p=0.016) and rapid increases in heart rate (24-h, p=0.004; 48-h, p=0.001). Cardiac output increased in 48-h runners (p=0.012) and stroke volume decreased in 24-h runners (p=0.009) at post-test. Six of 20 (30%) 24-h and 4 of 16 (25%) 48-h runners had high-sensitivity troponin T values above the reference interval after the races. N-terminal proB-type natriuretic peptide levels showed a 15-fold increase in 24-h runners and a 10-fold increase in 48-h runners at post-race. There was a positive correlation between delta N-terminal proB-type natriuretic peptide and running mileage (rs=0.629, p=0.003) in 24-h ultra-marathoners. In conclusion, stroke volume and cardiac output showed inconsistent changes between the 2 groups. Average running speed has a significant effect on post-exercise elevation in cardiac biomarkers.


Assuntos
Biomarcadores/sangue , Coração/fisiologia , Corrida de Maratona/fisiologia , Adulto , Atletas , Débito Cardíaco , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Volume Sistólico , Troponina T/sangue
12.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202889

RESUMO

In this paper, small-sized acoustic horns, the sensitivity enhancement package for the MEMS-based thermal acoustic particle velocity sensor, have been designed and optimized. Four kinds of acoustic horns, including tube horn, double cone horn, double paradox horn, and exponential horn, were analyzed through numerical calculation. Considering both the amplification factor and effective length of amplification zone, a small-sized double cone horn with middle tube is designed and further optimized. A three-wire thermal acoustic particle velocity sensor was fabricated and packaged in the 3D printed double cone tube (DCT) horn. Experiment results show that an amplification factor of 6.63 at 600 Hz and 6.93 at 1 kHz was achieved. A good 8-shape directivity pattern was also obtained for the optimized DCT horn with the lateral inhibition ratio of 50.3 dB. No additional noise was introduced, demonstrating the DCT horn's potential in improving the sensitivity of acoustic particle velocity sensors.


Assuntos
Sistemas Microeletromecânicos , Acústica , Animais , Desenho de Equipamento , Ruído
13.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204449

RESUMO

We recently found that, in human osteoblasts, Homer1 complexes to Calcium-sensing receptor (CaSR) and mediates AKT initiation via mechanistic target of rapamycin complex (mTOR) complex 2 (mTORC2) leading to beneficial effects in osteoblasts including ß-catenin stabilization and mTOR complex 1 (mTORC1) activation. Herein we further investigated the relationship between Homer1 and CaSR and demonstrate a link between the protein levels of CaSR and Homer1 in human osteoblasts in primary culture. Thus, when siRNA was used to suppress the CaSR, we observed upregulated Homer1 levels, and when siRNA was used to suppress Homer1 we observed downregulated CaSR protein levels using immunofluorescence staining of cultured osteoblasts as well as Western blot analyses of cell protein extracts. This finding was confirmed in vivo as the bone cells from osteoblast specific CaSR-/- mice showed increased Homer1 expression compared to wild-type (wt). CaSR and Homer1 protein were both expressed in osteocytes embedded in the long bones of wt mice, and immunofluorescent studies of these cells revealed that Homer1 protein sub-cellular localization was markedly altered in the osteocytes of CaSR-/- mice compared to wt. The study identifies additional roles for Homer1 in the control of the protein level and subcellular localization of CaSR in cells of the osteoblast lineage, in addition to its established role of mTORC2 activation downstream of the receptor.


Assuntos
Proteínas de Arcabouço Homer/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Osteoblastos/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Animais , Cálcio/metabolismo , Linhagem da Célula , Sobrevivência Celular , Células Cultivadas , Feminino , Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Fosforilação , Ligação Proteica , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Detecção de Cálcio/genética
14.
J Biol Chem ; 294(44): 16337-16350, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527082

RESUMO

The calcium-sensing receptor (CaSR) is critical for skeletal development, but its mechanism of action in osteoblasts is not well-characterized. In the central nervous system (CNS), Homer scaffolding proteins form signaling complexes with two CaSR-related members of the G protein-coupled receptor (GPCR) family C, metabotropic glutamate receptor 1 (mGluR1) and mGluR5. Here, we show that CaSR and Homer1 are co-expressed in mineralized mouse bone and also co-localize in primary human osteoblasts. Co-immunoprecipitation experiments confirmed that Homer1 associates with CaSR in primary human osteoblasts. The CaSR-Homer1 protein complex, whose formation was increased in response to extracellular Ca2+, was bound to mechanistic target of rapamycin (mTOR) complex 2 (mTORC2), a protein kinase that phosphorylates and activates AKT Ser/Thr kinase (AKT) at Ser473 siRNA-based gene-silencing assays with primary osteoblasts revealed that both CaSR and Homer1 are required for extracellular Ca2+-stimulated AKT phosphorylation and thereby inhibit apoptosis and promote AKT-dependent ß-catenin stabilization and cellular differentiation. To confirm the role of the CaSR-Homer1 complex in AKT initiation, we show that in HEK-293 cells, co-transfection with both Homer1c and CaSR, but neither with Homer1c nor CaSR alone, establishes sensitivity of AKT-Ser473 phosphorylation to increases in extracellular Ca2+ concentrations. These findings indicate that Homer1 mediates CaSR-dependent AKT activation via mTORC2 and thereby stabilizes ß-catenin in osteoblasts.


Assuntos
Proteínas de Arcabouço Homer/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Osteoblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Detecção de Cálcio/metabolismo , beta Catenina/metabolismo , Animais , Apoptose/fisiologia , Cálcio/metabolismo , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Receptores de Detecção de Cálcio/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
15.
Development ; 144(2): 221-234, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28096214

RESUMO

Fractures heal predominantly through the process of endochondral ossification. The classic model of endochondral ossification holds that chondrocytes mature to hypertrophy, undergo apoptosis and new bone forms by invading osteoprogenitors. However, recent data demonstrate that chondrocytes transdifferentiate to osteoblasts in the growth plate and during regeneration, yet the mechanism(s) regulating this process remain unknown. Here, we show a spatially-dependent phenotypic overlap between hypertrophic chondrocytes and osteoblasts at the chondro-osseous border in the fracture callus, in a region we define as the transition zone (TZ). Hypertrophic chondrocytes in the TZ activate expression of the pluripotency factors [Sox2, Oct4 (Pou5f1), Nanog], and conditional knock-out of Sox2 during fracture healing results in reduction of the fracture callus and a delay in conversion of cartilage to bone. The signal(s) triggering expression of the pluripotency genes are unknown, but we demonstrate that endothelial cell conditioned medium upregulates these genes in ex vivo fracture cultures, supporting histological evidence that transdifferentiation occurs adjacent to the vasculature. Elucidating the cellular and molecular mechanisms underlying fracture repair is important for understanding why some fractures fail to heal and for developing novel therapeutic interventions.


Assuntos
Transdiferenciação Celular/genética , Condrócitos/fisiologia , Neovascularização Fisiológica/fisiologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Células-Tronco Pluripotentes/fisiologia , Animais , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Calo Ósseo/crescimento & desenvolvimento , Calo Ósseo/metabolismo , Cartilagem/citologia , Cartilagem/fisiologia , Células Cultivadas , Condrócitos/citologia , Condrogênese/fisiologia , Consolidação da Fratura/genética , Consolidação da Fratura/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Fisiológica/genética , Osteoblastos/citologia , Regulação para Cima/genética
16.
BMC Public Health ; 20(1): 78, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952485

RESUMO

BACKGROUND: Motorcycle full-coverage helmet use may reduce fatalities and head injuries. METHODS: This retrospective cohort study extracted injury data from eight level-I trauma centres in Taiwan and performed a questionnaire survey to investigate injuries sustained by motorcyclists for the period between January 2015 and June 2017. RESULTS: As many as 725 patients participated in the questionnaire survey and reported their helmet types or phone use during crashes. The results of multivariate logistic models demonstrated that nonstandard helmet (half or open-face helmet) use was associated with an increased risk of head injuries and more severe injuries (injury severity score ≥ 8). Drunk riding and phone use appeared to be two important risk factors for head injuries and increased injury severity. Anaemia was also found to be a determinant of head injuries." CONCLUSIONS: Compared to full-coverage helmets, nonstandard provide less protection against head injuries and increased injury severity among motorcyclists.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Traumatismos Craniocerebrais/prevenção & controle , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Motocicletas , Adolescente , Adulto , Idoso , Traumatismos Craniocerebrais/epidemiologia , Feminino , Humanos , Escala de Gravidade do Ferimento , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Centros de Traumatologia , Adulto Jovem
17.
Psychol Med ; 49(14): 2397-2404, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30415649

RESUMO

BACKGROUND: Bipolar disorder is a highly heritable mental illness that transmits intergeneratively. Previous studies supported that first-degree relatives (FDRs), such as parents, offspring, and siblings, of patients with bipolar disorder, had a higher risk of bipolar disorder. However, whether FDRs of bipolar patients have an increased risk of schizophrenia, major depressive disorder (MDD), autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD) remains unclear. METHODS: Among the entire population in Taiwan, 87 639 patients with bipolar disorder and 188 290 FDRs of patients with bipolar disorder were identified in our study. The relative risks (RRs) of major psychiatric disorders were assessed among FDRs of patients with bipolar disorder. RESULTS: FDRs of patients with bipolar disorder were more likely to have a higher risk of major psychiatric disorders, including bipolar disorder (RR 6.12, 95% confidence interval (CI) 5.95-6.30), MDD (RR 2.89, 95% CI 2.82-2.96), schizophrenia (RR 2.64, 95% CI 2.55-2.73), ADHD (RR 2.21, 95% CI 2.13-2.30), and ASD (RR 2.10, 95% CI 1.92-2.29), than the total population did. These increased risks for major psychiatric disorders were consistent across different familial kinships, such as parents, offspring, siblings, and twins. A dose-dependent relationship was also found between risk of each major psychiatric disorder and numbers of bipolar patients. CONCLUSIONS: Our study was the first study to support the familial coaggregation of bipolar disorder with other major psychiatric disorders, including schizophrenia, MDD, ADHD, and ASD, in a Taiwanese (non-Caucasian) population. Given the elevated risks of major psychiatric disorders, the public health government should pay more attention to the mental health of FDRs of patients with bipolar disorder.


Assuntos
Transtorno Bipolar/genética , Transtornos Mentais/genética , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Espectro Autista/genética , Bases de Dados Factuais , Transtorno Depressivo Maior/genética , Doenças em Gêmeos/genética , Saúde da Família , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Esquizofrenia/genética , Taiwan , Adulto Jovem
18.
Psychiatry Clin Neurosci ; 73(4): 187-193, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30588705

RESUMO

AIM: Fibromyalgia is often comorbid with depression, and less than half those patients achieve satisfactory improvement after adequate pharmacological intervention. The investigation of repetitive transcranial magnetic stimulation (rTMS) at left dorsolateral prefrontal cortex for modified-2010 American College of Rheumatology (ACR) fibromyalgia and major depressive disorder (MDD) is still in its infancy. METHODS: In this double-blind, randomized, sham-control study, subjects diagnosed with ACR-2010 fibromyalgia and DSM-IV-TR MDD were recruited and received either active or sham interventions for 2 weeks. Hamilton Depression Rating Scale (HDRS) and the 10-cm visual analogue pain scale were evaluated at baseline, week 1, and week 2. Multivariable generalized estimating equations analysis was performed for the association between depression and pain scores at each checkpoint. RESULTS: Twenty subjects were recruited. There was a significant difference over the 2 weeks between the rTMS and sham stimulation groups (P = 0.029), but subgroup analyses were further performed due to significant interaction of group and HDRS on pain outcomes (P = 0.020). The active group had significant improvement in pain at week 2 compared with week 1 (P = 0.021), but the control group did not have any improvement in pain (P = 0.585). Of the mild-moderate depression patients, the pain score in the active group was significantly lower than in the sham group at week 1 (P = 0.001) and at week 2 (P < 0.001). For the severe depression group, there was significantly lower pain over the 2 weeks in the active group (P = 0.045) but the sham group had significantly relapsing pain at week 2 (P < 0.001). CONCLUSION: Left prefrontal rTMS has an analgesic effect in modified-ACR 2010-defined fibromyalgia and MDD patients. Further investigation is required, however, in order to determine how to regulate the different rTMS treatment protocols according to individual baseline depression severity in patients with MDD and fibromyalgia.


Assuntos
Transtorno Depressivo Maior/terapia , Fibromialgia/terapia , Avaliação de Resultados em Cuidados de Saúde , Manejo da Dor/métodos , Córtex Pré-Frontal , Estimulação Magnética Transcraniana/métodos , Adulto , Comorbidade , Transtorno Depressivo Maior/epidemiologia , Método Duplo-Cego , Feminino , Fibromialgia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Índice de Gravidade de Doença
19.
Semin Cell Dev Biol ; 49: 11-23, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26688334

RESUMO

Parathyroid hormone (PTH)-related peptide (PTHrP) controls the pace of pre- and post-natal growth plate development by activating the PTH1R in chondrocytes, while PTH maintains mineral and skeletal homeostasis by modulating calciotropic activities in kidneys, gut, and bone. The extracellular calcium-sensing receptor (CaSR) is a member of family C, G protein-coupled receptor, which regulates mineral and skeletal homeostasis by controlling PTH secretion in parathyroid glands and Ca(2+) excretion in kidneys. Recent studies showed the expression of CaSR in chondrocytes, osteoblasts, and osteoclasts and confirmed its non-redundant roles in modulating the recruitment, proliferation, survival, and differentiation of the cells. This review emphasizes the actions of CaSR and PTH1R signaling responses in cartilage and bone and discusses how these two signaling cascades interact to control growth plate development and maintain skeletal metabolism in physiological and pathological conditions. Lastly, novel therapeutic regimens that exploit interrelationship between the CaSR and PTH1R are proposed to produce more robust osteoanabolism.


Assuntos
Osteogênese , Receptor Tipo 1 de Hormônio Paratireóideo/fisiologia , Receptores de Detecção de Cálcio/fisiologia , Transdução de Sinais , Animais , Remodelação Óssea , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Cálcio/metabolismo , Cartilagem/citologia , Cartilagem/fisiologia , Diferenciação Celular , Condrócitos/fisiologia , Lâmina de Crescimento/fisiologia , Humanos , Hormônio Paratireóideo/fisiologia
20.
J Biol Chem ; 292(43): 17845-17856, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28893908

RESUMO

Galectins are a family of lectins that bind ß-galactosides through their conserved carbohydrate recognition domain (CRD) and can induce aggregation with glycoproteins or glycolipids on the cell surface and thereby regulate cell activation, migration, adhesion, and signaling. Galectin-3 has an intrinsically disordered N-terminal domain and a canonical CRD. Unlike the other 14 known galectins in mammalian cells, which have dimeric or tandem-repeated CRDs enabling multivalency for various functions, galectin-3 is monomeric, and its functional multivalency therefore is somewhat of a mystery. Here, we used NMR spectroscopy, mutagenesis, small-angle X-ray scattering, and computational modeling to study the self-association-related multivalency of galectin-3 at the residue-specific level. We show that the disordered N-terminal domain (residues ∼20-100) interacts with itself and with a part of the CRD not involved in carbohydrate recognition (ß-strands 7-9; residues ∼200-220), forming a fuzzy complex via inter- and intramolecular interactions, mainly through hydrophobicity. These fuzzy interactions are characteristic of intrinsically disordered proteins to achieve liquid-liquid phase separation, and we demonstrated that galectin-3 can also undergo liquid-liquid phase separation. We propose that galectin-3 may achieve multivalency through this multisite self-association mechanism facilitated by fuzzy interactions.


Assuntos
Galectina 3/química , Proteínas Intrinsicamente Desordenadas/química , Proteínas Sanguíneas , Galectina 3/genética , Galectina 3/metabolismo , Galectinas , Humanos , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Domínios Proteicos , Difração de Raios X
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa