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1.
Iran J Allergy Asthma Immunol ; 22(5): 430-439, 2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-38085145

RESUMO

Asthma, characterized by persistent inflammation and increased sensitivity of the airway, is the most common chronic condition among children. Novel, safe, and reliable treatment strategies are the focus of current research on pediatric asthma. Amygdalin, mainly present in bitter almonds, has anti-inflammatory and immunoregulatory potential, but its effect on asthma remains uninvestigated. Here, the impact of amygdalin on the thymic stromal lymphopoietin (TSLP)-dendritic cell (DC)-OX40L axis was investigated. A BALB/c mouse model for allergic asthma was established using the ovalbumin-sensitization method. Amygdalin treatment was administered between days 21 and 27 of the protocol. Cell numbers and hematoxylin and eosin (H&E) staining in bronchoalveolar lavage fluid (BALF) were used to observe the impact of amygdalin on airway inflammation. TSLP, IL-4, IL-5, IL-13, and IFN-γ concentrations were determined via Enzyme-linked immunosorbent assay (ELISA). TSLP, GATA-3, and T-bet proteins were measured using western blotting. Cell-surface receptor expression on DCs (MHC II, CD80, and CD86) was assessed via flow cytometry. OX40L mRNA and protein levels were detected using western blotting and qRT-PCR, respectively. Amygdalin treatment attenuated airway inflammation decreased BALF TSLP levels, inhibited DC maturation, restrained TSLP-induced DC surface marker expression (MHCII, CD80, and CD86), and further decreased OX40L levels in activated DCs. This occurred together with decreased Th2 cytokine levels (IL-4, IL-5, and IL-13) and GATA3 expression, whereas Th1 cytokine (IFN-γ) levels and T-bet expression increased. Amygdalin thus regulates the Th1/Th2 balance through the TSLP-DC-OX40L axis to participate in inflammation development in the airways, providing a basis for potential allergic asthma treatments.


Assuntos
Amigdalina , Asma , Camundongos , Animais , Criança , Humanos , Linfopoietina do Estroma do Timo , Interleucina-13/metabolismo , Interleucina-13/farmacologia , Amigdalina/farmacologia , Amigdalina/uso terapêutico , Amigdalina/metabolismo , Ligante OX40/metabolismo , Ligante OX40/farmacologia , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Interleucina-5/farmacologia , Citocinas/metabolismo , Asma/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Células Th2/metabolismo , Células Dendríticas/metabolismo , Camundongos Endogâmicos BALB C
2.
J Clin Endocrinol Metab ; 107(7): e2690-e2701, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35428889

RESUMO

CONTEXT: Premenopausal women with idiopathic osteoporosis (PreMenIOP) have marked deficits in bone density, microstructure, and strength. OBJECTIVE: To define effects of treatment with teriparatide followed by denosumab on lumbar spine (LS) volumetric bone mineral density (vBMD) and stiffness by finite element analysis assessed on central quantitative computed tomography (cQCT) scans. DESIGN, SETTINGS, AND PARTICIPANTS: Ancillary analysis of baseline, post-teriparatide, and post-denosumab cQCT scans from a randomized trial of 41 women allocated to teriparatide (20 mcg daily; n = 28) or placebo (n = 11). After 6 months, those on teriparatide continued for 18 months, and those on placebo switched to teriparatide for 24 months. After completing teriparatide, 33 enrolled in a Phase 2B extension with denosumab (60 mg every 6 months) for 12 months. MAIN OUTCOME MEASURES: Primary outcomes were percentage change from baseline in LS trabecular vBMD and stiffness after teriparatide and between end of teriparatide and completing denosumab. Percentage change from baseline in LS trabecular vBMD and stiffness after sequential teriparatide and denosumab were secondary outcomes. FINDINGS: There were large increases (all Ps < 0.001) in trabecular vBMD (25%), other vBMD parameters, and stiffness (21%) after teriparatide. Statistically significant increases in trabecular vBMD (10%; P < 0.001) and other vBMD parameters (P = 0.03-0.001) were seen after denosumab, while stiffness increased by 7% (P = 0.068). Sequential teriparatide and denosumab led to highly significant (all Ps < 0.001) increases LS trabecular vBMD (43%), other vBMD parameters (15-31%), and stiffness (21%). CONCLUSIONS: The large and statistically significant increases in volumetric density and stiffness after sequential treatment with teriparatide followed by denosumab are encouraging and support use of this regimen in PreMenIOP.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Densidade Óssea , Denosumab/farmacologia , Denosumab/uso terapêutico , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Osteoporose/tratamento farmacológico , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida
3.
J Clin Endocrinol Metab ; 106(4): e1868-e1879, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33098299

RESUMO

CONTEXT: The prevalence of obesity is burgeoning among African American and Latina women; however, few studies investigating the skeletal effects of bariatric surgery have focused on these groups. OBJECTIVE: To investigate long-term skeletal changes following Roux-en-Y gastric bypass (RYGB) in African American and Latina women. DESIGN: Four-year prospective cohort study. PATIENTS: African American and Latina women presenting for RYGB (n = 17, mean age 44, body mass index 44 kg/m2) were followed annually for 4 years postoperatively. MAIN OUTCOME MEASURES: Dual-energy x-ray absorptiometry (DXA) measured areal bone mineral density (aBMD) at the spine, hip, and forearm, and body composition. High-resolution peripheral quantitative computed tomography measured volumetric bone mineral density (vBMD) and microarchitecture. Individual trabecula segmentation-based morphological analysis assessed trabecular morphology and connectivity. RESULTS: Baseline DXA Z-Scores were normal. Weight decreased ~30% at Year 1, then stabilized. Parathyroid hormone (PTH) increased by 50% and 25-hydroxyvitamin D was stable. By Year 4, aBMD had declined at all sites, most substantially in the hip. There was significant, progressive loss of cortical and trabecular vBMD, deterioration of microarchitecture, and increased cortical porosity at both the radius and tibia over 4 years. There was loss of trabecular plates, loss of axially aligned trabeculae, and decreased trabecular connectivity. Whole bone stiffness and failure load declined. Risk factors for bone loss included greater weight loss, rise in PTH, and older age. CONCLUSIONS: African American and Latina women had substantial and progressive bone loss, deterioration of microarchitecture, and trabecular morphology following RYGB. Further studies are critical to understand the long-term skeletal consequences of bariatric surgery in this population.


Assuntos
Doenças Ósseas Metabólicas/etnologia , Doenças Ósseas Metabólicas/etiologia , Derivação Gástrica/efeitos adversos , Absorciometria de Fóton , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Composição Corporal , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/diagnóstico , Estudos de Coortes , Feminino , Seguimentos , Derivação Gástrica/estatística & dados numéricos , Hispânico ou Latino/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , New York/epidemiologia , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/etnologia , Obesidade Mórbida/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios X
4.
Bone ; 144: 115825, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33348128

RESUMO

Spinal cord injury (SCI) results in marked atrophy of sublesional skeletal muscle and substantial loss of bone. In this study, the effects of prolonged electrical stimulation (ES) and/or testosterone enanthate (TE) on muscle mass and bone formation in a rat model of SCI were tested. Compared to sham-transected animals, a significant reduction of the mass of soleus, plantaris and extensor digitorum longus (EDL) muscles was observed in animals 6 weeks post-SCI. Notably, ES or ES + TE resulted in the increased mass of the EDL muscles. ES or ES + TE significantly decreased mRNA levels of muscle atrophy markers (e.g., MAFbx and MurF1) in the EDL. Significant decreases in bone mineral density (BMD) (-27%) and trabecular bone volume (-49.3%) at the distal femur were observed in animals 6 weeks post injury. TE, ES and ES + TE treatment significantly increased BMD by +6.4%, +5.4%, +8.5% and bone volume by +22.2%, and +56.2% and+ 60.2%, respectively. Notably, ES alone or ES + TE resulted in almost complete restoration of cortical stiffness estimated by finite element analysis in SCI animals. Osteoblastogenesis was evaluated by colony-forming unit-fibroblastic (CFU-F) staining using bone marrow mesenchymal stem cells obtained from the femur. SCI decreased the CFU-F+ cells by -56.8% compared to sham animals. TE or ES + TE treatment after SCI increased osteoblastogenesis by +74.6% and +67.2%, respectively. An osteoclastogenesis assay revealed significantly increased TRAP+ multinucleated cells (+34.8%) in SCI animals compared to sham animals. TE, ES and TE + ES treatment following SCI markedly decreased TRAP+ cells by -51.3%, -40.3% and -46.9%, respectively. Each intervention greatly reduced the ratio of RANKL to OPG mRNA of sublesional long bone. Collectively, our findings demonstrate that after neurologically complete paralysis, dynamic muscle resistance exercise by ES reduced muscle atrophy, downregulated genes involved in muscle wasting, and restored mechanical loading to sublesional bone to a degree that allowed for the preservation of bone by inhibition of bone resorption and/or by facilitating bone formation.


Assuntos
Traumatismos da Medula Espinal , Animais , Densidade Óssea , Osso e Ossos , Estimulação Elétrica , Membro Posterior , Músculo Esquelético , Ratos , Traumatismos da Medula Espinal/terapia
5.
Micromachines (Basel) ; 11(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32024180

RESUMO

Aluminum alloys are widely used, but they are prone to contamination or damage under harsh working environments. In this paper, a self-cleaning superhydrophobic aluminum alloy surface with good corrosion resistance was successfully fabricated via the combination of sand peening and electrochemical oxidation, and it was subsequently covered with a fluoroalkylsilane (FAS) film. The surface morphology, surface wettability, and corrosion resistance were investigated using a scanning electron microscope (SEM), an optical contact angle measurement, and an electrochemical workstation. The results show that binary rough structures and an FAS film with a low surface energy on the Al alloy surfaces confer good superhydrophobicity with a water contact angle of 167.5 ± 1.1° and a sliding angle of 2.5 ± 0.7°. Meanwhile, the potentiodynamic polarization curve shows that the corrosion potential has a positively shifted trend, and the corrosion current density decreases by three orders of magnitude compared with that of the original aluminum alloy sample. In addition, the chemical stability of the as-prepared superhydrophobic surface was evaluated by dripping test using solutions with different pH values for different immersion time. It indicates that the superhydrophobic surface could provide long-term corrosion protection for aluminum alloys. Consequently, the as-prepared superhydrophobic surface has excellent contamination resistance and self-cleaning efficacy, which are important for practical applications.

6.
Spinal Cord ; 58(3): 309-317, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31664187

RESUMO

STUDY DESIGN: Animal study. OBJECTIVE: This study examined how soon after spinal cord injury (SCI) bone loss occurs, and investigated the underlying molecular mechanism. METHODS: Eight-week-old male Wistar rats underwent complete transection of the thoracic spinal cord at T3-4 or sham operation (n = 10-12 per group). Blood, hindlimb bone samples, and bone marrows were collected at 2 and 7 days after SCI. RESULTS: The neurologically motor-complete SCI causes loss of bone mass and deterioration of trabecular bone microstructure as early as 2 days after injury; these skeletal defects become more evident at 7 days. These changes are associated with a dramatic increase in levels of bone resorption maker CTX in blood. Alternations of gene expression in hindlimb bone tissues and bone marrow cells at the first week after SCI were examined. Gene expressions responsible for both bone resorption and formation are increased at 2 days post-SCI, and the associated bone loss and bone deterioration are likely the result of higher levels of osteoclastic resorption over osteoblastic formation, as may be extrapolated from findings at molecular levels. CONCLUSIONS: Rapid bone loss occurs as early as 2 days after motor-complete SCI and interventions for inhibiting bone resorption and prompting bone formation should start as soon as possible after the injury to prevent bone loss.


Assuntos
Reabsorção Óssea/etiologia , Traumatismos da Medula Espinal/complicações , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
7.
Arch Osteoporos ; 14(1): 70, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31250235

RESUMO

Significant correlations for bone mineral density and bone microstructure between spinal and non-spinal skeletal sites (distal radius and proximal femur) in adolescent idiopathic scoliosis (AIS) patients were observed, indicating that proximal femoral DXA and distal radial HR-pQCT could provide valid clinical assessments in patients with AIS. PURPOSE: Low bone mass is an important feature of adolescent idiopathic scoliosis (AIS), which is a complex 3D spinal deformity that affects girls during puberty. However, no clinical imaging modality is suitable for regular monitoring on their spinal bone qualities in rapid growth period. Therefore, we investigated whether bone mineral density (BMD) and bone microstructure at non-spinal sites correlated with BMD and mechanical property in the spine in AIS patients. METHODS: Thirty-two AIS girls (16.7 ± 3.5 years old with mean Cobb angle of 67 ± 11°) who underwent pre-operative spine CT examination for navigation surgery were recruited. Volumetric BMD (vBMD) of lumbar spine (LS) was measured by quantitative computed tomography (QCT), vBMD and bone microstructure of distal radius (DR) by high-resolution peripheral QCT (HR-pQCT) and areal BMDs of total hip (TH) and femoral necks (FN) by dual-energy X-ray absorptiometry (DXA). Biomechanical properties of the DR and LS were estimated by finite element analysis (FEA). Pearson correlation was performed to study the correlation between bone parameters at these three sites. RESULTS: LS vBMD correlated significantly with both FN and TH aBMD (R = 0.663-0.725, both p < 0.01) and with DR microstructural parameters (R = 0.380-0.576, all p < 0.05). Mechanical properties of LS and DR were also correlated (R = 0.398, p = 0.039). CONCLUSIONS: Bone measurement at proximal femur and distal radius could provide an additional predictive power in estimating the bone changes at spine, which is the primary site of deformity in AIS patients. Our result indicated that DXA and HR-pQCT could provide a valid surrogate for spine bone measurements in AIS patients.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Adolescente , Osso e Ossos/anatomia & histologia , Correlação de Dados , Feminino , Fêmur , Colo do Fêmur , Análise de Elementos Finitos , Humanos , Cifose , Vértebras Lombares , Rádio (Anatomia) , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
Mol Cell Endocrinol ; 485: 35-43, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30707916

RESUMO

Intracellular Ca2+ signaling plays an essential role in synaptic plasticity. This study examined the effect of BPA on concentration of intracellular Ca2+ ([Ca2+]i) by measuring fluorescence intensity of Ca2+ in hippocampal neurons in vitro. The results showed that BPA for 30 min exerted dose-dependently dual effects on glutamate-elevated [Ca2+]i: BPA at 1-10 µM suppressed but at 1-100 nM enhanced glutamate-raised [Ca2+]i. BPA-potentiated [Ca2+]i was blocked by the antagonist of NMDA receptor and was eliminated by an estrogen-related receptor gamma (ERRγ) antagonist rather than an AR antagonist. Both inhibitors of MAPK/ERKs and MAPK/p38 blocked BPA-enhanced [Ca2+]i. Co-treatment of BPA with 17ß-E2 or DHT eliminated the enhancement of 17ß-E2, DHT, and BPA in glutamate-elevated [Ca2+]i. These results suggest that BPA at nanomole level rapidly enhances Ca2+ influx through NMDA receptor by ERRγ-mediated MAPK/ERKs and MAPK/p38 signaling pathways. However, BPA antagonizes both estrogen and androgen enhancing NMDA receptor-mediated Ca2+ influx in hippocampal neurons.


Assuntos
Compostos Benzidrílicos/efeitos adversos , Sinalização do Cálcio/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Hipocampo/citologia , Fenóis/efeitos adversos , Animais , Compostos Benzidrílicos/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Hipocampo/diagnóstico por imagem , Hipocampo/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fenóis/farmacologia , Ratos , Ratos Sprague-Dawley , Análise de Célula Única
9.
Bone ; 107: 181-187, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29154969

RESUMO

Individuals with cystic fibrosis (CF) have lower bone mineral density (BMD) by DXA and are at higher risk of fracture than healthy controls. However, the 2-dimensional measurement of areal BMD (aBMD) provided by DXA is influenced by bone size and the true extent of the bone deficit is unclear. Our objective was to use high-resolution peripheral quantitative computed tomography (HR-pQCT) and individual trabecula segmentation (ITS) analysis to compare volumetric BMD (vBMD), microarchitecture and estimated strength at the distal radius and tibia in 26 young adults with CF and 26 controls matched for age, gender, and race. To assess the effect of limb length and minimize the confounding effects of size on HR-pQCT outcomes, we scanned participants at both the standard fixed HR-pQCT measurement sites and at a subject-specific relative site that varied according to limb length. CF participants did not differ significantly in age, height, weight, or BMI from controls. Ulnar and tibial lengths were 9mm shorter in CF patients, though differences were not significant. CF patients had significantly lower BMI-adjusted aBMD by DXA at the lumbar spine (8.9%, p<0.01), total hip (11.5%, p<0.01) and femoral neck (14.5%, p<0.01), but not at the forearm. At the fixed radius site, thickness of trabecular plates and torsional stiffness were significantly lower in CF participants than controls. At the relative radius site, only torsional stiffness was significantly lower in CF participants. At the tibia, total, trabecular and cortical vBMD were significantly lower at both fixed and relative sites in CF participants, with fewer, more widely-spaced trabecular plates, lower trabecular connectivity, and lower axial and torsional stiffness. Our results confirm that aBMD is lower at the spine and hip in young adults with CF, independent of BMI and body size. We also conclude that vBMD and stiffness are lower at the weight-bearing tibia. The pathogenesis of these differences in bone density and strength at the tibia appear to be related to trabecular drop-out and reduced trabecular connectivity and to be independent of differences in limb length, as assessed by scanning participants at both standard and relative sites. We concluded that significant deficits in bone structure and strength persist in young adults with CF, despite advances in care that permit them to attain relatively normal height and weight.


Assuntos
Osso e Ossos/patologia , Fibrose Cística/complicações , Fibrose Cística/patologia , Adulto , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiopatologia , Feminino , Humanos , Masculino , Rádio (Anatomia) , Coluna Vertebral , Tíbia , Tomografia Computadorizada por Raios X
10.
Chemosphere ; 195: 567-575, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29278848

RESUMO

Bisphenol A (BPA), a common environmental endocrine disruptor, modulates estrogenic, antiestrogenic, and antiandrogenic effects throughout the lifespan. Recent studies found more obvious adverse effect of BPA on some neurobehavior in males than that in females. In this study, BPA at 10-100 nM rapidly increased the densities of the dendrite spine and synapse in cultured hippocampal neurons of rats in vitro within 1 h. Co-treatment of BPA (100 nM) with dihydrotestosterone (DHT, 10 nM) or with 17ß-E2 (10 nM) completely eliminated the promotion of DHT or 17ß-E2 in the densities of the dendritic spine and synapse. Pretreatment of estrogen receptors (ERs) antagonist ICI182,780 but not of androgen receptors (ARs) antagonist flutamide (Flu) for 30min completely blocked BPA-enhanced densities of the dendritic spine and synapse. Pretreatment of flutamide for 30min before BPA and DHT completely rescued BPA-enhanced densities of the dendritic spine and synapse. Furthermore, pretreatment of ERK1/2 inhibitor U0126 or p38 inhibitor SB203580 entirely eliminated BPA-induced increases in the densities of the dendritic spine and synapse. Meanwhile, BPA (100 nM) enhanced long-term potentiation (LTP) induction of dentate gyrus in hippocampal slices of younger male rats, which was not blocked by co-incubation of flutamide but was inhibited by pretreatment of an P38 inhibitor SB203580. Co-application of BPA with DHT inhibited DHT-suppressed LTP. These results are the first demonstrating the antagonism of BPA to the rapid modification of DHT in synaptic plasticity. However, BPA alone rapidly promotes spinogenesis and synaptic activity through ER instead of AR, and both ERKs and p38 signaling pathways are involved in these processes.


Assuntos
Compostos Benzidrílicos/farmacologia , Espinhas Dendríticas/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fenóis/farmacologia , Animais , Disruptores Endócrinos/farmacologia , Feminino , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Masculino , Plasticidade Neuronal/efeitos dos fármacos , Ratos , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Sinapses/efeitos dos fármacos
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