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1.
Plants (Basel) ; 11(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35214853

RESUMO

Particulate matter (PM) exposure may cause adverse health effects such as respiratory disorders. We evaluated the protective effects of various Opuntia ficus-indica (OFI) extracts on airway inflammation associated with exposure to PM10D with an aerodynamic diameter <10 µm (PM10) and diesel exhaust particles (DEP). BALB/c mice were exposed to PM10D via intranasal tracheal injection three times over a period of 12 days and various OFI extracts (water, 30% ethanolic, or 50% ethanolic extracts) were administered orally for 12 days. All OFI extracts suppressed neutrophil infiltration and the number of immune cells (CD3+/CD4+, CD3+/CD8+, and Gr-1+/CD11b) in bronchoalveolar lavage fluid (BALF) and lungs. OFI extracts decreased the expression of cytokines and chemokines, including chemokine (C-X-C motif) ligand (CXCL)-1, interleukin (IL)-17, macrophage inflammatory protein-2, tumor necrosis factor (TNF)-α, cyclooxygenase-2, IL-1α, IL-1ß, IL-5, IL-6, transient receptor potential cation channel subfamily V member 1, and mucin 5AC, and inhibited IRAK-1, TNF-α, and CXCL-1 localization in BALF and lungs of mice with PM10D-induced airway inflammation. Serum asymmetric and symmetric dimethyl arginine levels were also decreased by OFI extracts treatment. Moreover, all OFI extracts restored histopathological damage in the trachea and lungs of mice with PM10D-induced airway inflammation. These results indicate that OFI extracts may be used to prevent and treat airway inflammation and respiratory diseases.

2.
Child Obes ; 18(7): 485-493, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35196146

RESUMO

Background: Many states have adopted school-based BMI screening or surveillance programs in an effort to address high rates of childhood obesity, some of which involve provision of confidential BMI reports to parents. While there is evidence that parents are attuned to information in the reports, there is less evidence showing that the reports are effective in preventing excess childhood weight gain. Methods: Data from Arkansas, the state with the nation's first and longest running and BMI screening program, were used to measure the impact of BMI reports. This was done through a regression discontinuity design that compared future BMI z-scores among children falling within a narrow band around the obese and overweight thresholds. We derived the effects of BMI reports by comparing students who received different types of reports around the relevant threshold. Results: While we are unable to detect any differences in BMI z-scores between the children who received the overweight report and the children who received the healthy weight report, we detected some differences between children who received the obese report and children who received the overweight report. These findings hold across subsamples by age, minority status, and school meal status. Conclusions: Based on these data, overweight or obese reports to do not meaningfully impact future BMI z-scores. This may be due, in part, to the format of parental reports, which may dampen the surprise element of an overweight or obese report.


Assuntos
Sobrepeso , Obesidade Infantil , Índice de Massa Corporal , Criança , Humanos , Sobrepeso/epidemiologia , Pais , Obesidade Infantil/epidemiologia , Estudantes , Aumento de Peso
3.
Health Econ Rev ; 11(1): 44, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34855042

RESUMO

BACKGROUND: Macroeconomic conditions are widely known to influence health outcomes through direct behavioral change or indirect mental effects of individuals. However, they have not received much attention in relation to childhood obesity. METHODS: Using gender-specific predicted employment growth rates as an index for labor market conditions, we analyze how economic shocks affect children's weight status in Arkansas. To understand the underlying mechanisms behind these results, we use data on individual time use to examine how economic shocks are related to activities related to children's weight. RESULTS: Improvement in the female labor market is associated with an increase in body mass index (BMI) and the probability that a child is overweight or obese, while an improvement in the male labor market has no significant effects on children's weight. This impact is particularly evident among female children, older children, and African-American children. We also find a negative effect of improvements in the female labor market on time spent on preparation for foods at home. CONCLUSIONS: These results suggest that a decrease in time spent preparing home-cooked foods might be a plausible explanation for the pro-cyclical relationship between children's weight and improvement in the labor market conditions. Thus, the policy implications of our paper should be aimed at mitigating the adverse effects of women's labor participation.

4.
Contemp Econ Policy ; 38(2): 270-288, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32194313

RESUMO

We investigate the effect of residential proximity to recreational trails on childhood body mass index (BMI). We find that children living within 0.5 miles of recreational trails have BMI z-scores that are 0.0412 to 0.0507 standard deviations lower than those who do not live within 0.5 miles of trails. We also find that living nearby trails reduces the probability of becoming obese by 1.6 percentage points. The impact for BMI z-score is larger for children qualifying for free or reduced-price meals and for Hispanic children. These findings suggest that improving neighborhood amenities conducive to physical activity may help reduce disparities in childhood obesity. (JEL I10, R10).

5.
J Biomed Opt ; 25(2): 1-9, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32061065

RESUMO

SIGNIFICANCE: Selective retina therapy (SRT) selectively targets the retinal pigment epithelium (RPE) and reduces negative side effects by avoiding thermal damages of the adjacent photoreceptors, the neural retina, and the choroid. However, the selection of proper laser energy for the SRT is challenging because of ophthalmoscopically invisible lesions in the RPE and different melanin concentrations among patients or even regions within an eye. AIM: We propose and demonstrate SRT monitoring based on speckle variance optical coherence tomography (svOCT) for dosimetry control. APPROACH: M-scans, time-resolved sequence of A-scans, of ex vivo bovine retina irradiated by 1.7-µs duration laser pulses were obtained by a swept-source OCT. SvOCT images were calculated as interframe intensity variance of the sequence. Spatial and temporal temperature distributions in the retina were numerically calculated in a 2-D retinal model using COMSOL Multiphysics. Microscopic images of treated spots were obtained before and after removing the upper neural retinal layer to assess the damage in both RPE and neural layers. RESULTS: SvOCT images show abrupt speckle variance changes when the retina is irradiated by laser pulses. The svOCT intensities averaged in RPE and photoreceptor layers along the axial direction show sharp peaks corresponding to each laser pulse, and the peak values were proportional to the laser pulse energy. The calculated temperatures in the neural retina layer and RPE were linearly fitted to the svOCT peak values, and the temperature of each lesion was estimated based on the fitting. The estimated temperatures matched well with previously reported results. CONCLUSION: We found a reliable correlation between the svOCT peak values and the degree of retinal lesion formation, which can be used for selecting proper laser energy during SRT.


Assuntos
Fotocoagulação a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Radiometria/métodos , Retina/diagnóstico por imagem , Retina/cirurgia , Tomografia de Coerência Óptica/métodos , Animais , Bovinos , Modelos Animais , Monitorização Fisiológica , Epitélio Pigmentado da Retina/diagnóstico por imagem , Epitélio Pigmentado da Retina/cirurgia
6.
Lasers Med Sci ; 33(1): 1-9, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28836013

RESUMO

The aim of this study is to examine the enhanced survival effect of ischemic skin flap by combined treatment with bone marrow-derived stem cells (BMSCs) and low-level light irradiation (LLLI). The neovasculogenic effect of BMSCs induced by LLLI was detected using a wound healing and tube formation assay. ICR mice were divided into four groups: control group, LLLI group, BMSCs group, and combine-treated group. The percentage of skin flap necrosis area was calculated on the seventh post-operative day. Specimens were harvested for histologic analyses. LLLI promoted BMSC migration and tube formation. The flap survival rate of combined treated group was significantly higher than that of the control group. Histologic results demonstrated a significant increase in neovascularization in the combined treatment group. This study demonstrates that combination treatment of BMSCs and LLLI could enhance the survival of ischemic skin flap in a mouse model.


Assuntos
Isquemia/radioterapia , Terapia com Luz de Baixa Intensidade , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Retalhos Cirúrgicos/irrigação sanguínea , Animais , Biomarcadores/metabolismo , Imuno-Histoquímica , Masculino , Células-Tronco Mesenquimais/efeitos da radiação , Camundongos Endogâmicos ICR , Necrose , Neovascularização Fisiológica/efeitos da radiação , Perfusão , Reprodutibilidade dos Testes , Cicatrização
7.
Sensors (Basel) ; 16(5)2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-27128916

RESUMO

We report development of optical parametric oscillator (OPO)-based mid-infrared laser system that utilizes a periodically poled nonlinear crystal pumped by a near-infrared (NIR) laser. We obtained a mid-infrared average output of 8 W at an injection current of 20 A from a quasi-phase-matched OPO using an external cavity configuration. Laser tissue ablation efficiency is substantially affected by several parameters, including an optical fluence rate, wavelength of the laser source, and the optical properties of target tissue. Dimensions of wavelength and radiant exposure dependent tissue ablation are quantified using Fourier domain optical coherence tomography and the ablation efficiency was compared to a non-converted NIR laser system.

8.
Biomed Microdevices ; 17(6): 109, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26494637

RESUMO

Injuries that result in the loss of limb functionality may be caused by the severing of the peripheral nerves within the affected limb. Several bioengineered peripheral nerve scaffolds have been developed in order to provide the physical support and topographical guidance necessary for the naturally disorganized axon outgrowth to reattach to distal nerve stumps as an alternative to other procedures, like nerve grafting. PDMS has been chosen for the base material of the scaffolds due to its biocompatibility, flexibility, transparency, and well-developed fabrication techniques. The process of observing the axon outgrowth across the nerve gaps with PDMS scaffolds has been challenging due to the limited number and fineness of longitudinal sections that can be extracted from harvested nerve tissue samples after implantation. To address this, multilayer microchannel scaffolds were developed with the object of providing more refined longitudinal observation of axon outgrowth by longitudinally 'sectioning' the device during fabrication, removing the need for much of the sample preparation process. This device was then implanted into the sciatic nerves of Lewis rats, and then harvested after two and four weeks to analyze the difference in nerve regeneration between two different time periods. The present layer by layer structure, which is separable after nerve regeneration and is treated as an individual layer during the histology process, provides the details of biological events during axonal regeneration. Confocal microscopic imaging showed the details of peripheral nerve regeneration including nerve branches and growth cones observable from within the microchannels of the multilayer PDMS microchannel scaffolds.


Assuntos
Dimetilpolisiloxanos/química , Regeneração Nervosa , Nervo Isquiático/crescimento & desenvolvimento , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Desenho de Equipamento , Tecido Nervoso/crescimento & desenvolvimento , Ratos , Ratos Endogâmicos Lew
9.
Opt Express ; 23(3): 3589-601, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836211

RESUMO

We have experimentally investigated the multi-parameter sensing characteristics in a novel all-fiber Sagnac loop hybrid interferometer based on a highly birefringent photonic crystal fiber with two asymmetric cores. The sensor device was based on a combination of two types of in-fiber interferences, the intra-core-mode Sagnac interference and the inter-core-mode Mach-Zehnder interference due to the distinct birefringent properties associated with the asymmetric cores. Fast Fourier transform analysis on the transmission spectra of the device exhibited six clear peaks in the spatial frequency domain. By examining the phase shift responses of two distinct Sagnac and one Mach-Zehnder interference peaks, the response matrix that enable simultaneous measurement of torsion, strain, and temperature could be obtained. The proposed all-fiber Sagnac loop hybrid interferometer has the advantages such as simplicity of the device structure, compact device size, and capability for simultaneous sensing of multiple parameters.

10.
Appl Opt ; 49(20): 3841-5, 2010 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-20648154

RESUMO

We report on a transverse load sensor with enhanced sensitivity through the use of a birefringent interferometer based on a highly birefringent photonic crystal fiber (HB-PCF). The transverse load sensitivity can be enhanced by using a fabricated HB-PCF having larger air holes on its fast axis. The transverse load sensitivity was measured to be high: approximately 2.17 nm/(N/cm). The temperature-induced undesirable effects can be ignored because transmission outputs of our HB-PCF were stable with the change of the temperature. The sensing probe can be compact because of its high birefringence with the order of 10(-3) and no bending loss.

11.
Artigo em Inglês | MEDLINE | ID: mdl-20580279

RESUMO

OBJECTIVES: Increased attention has been focused on determining the most efficacious materials for generalized bone grafts. This article presents the results of a histomorphometric analysis of bone healing in the calvaria of rabbits. The study compared the use of a tooth ash and plaster of Paris mixture alone, in association with platelet-rich plasma (PRP), and in association with fibrin sealant. STUDY DESIGN: Twelve rabbits were divided into control (group 1) and experimental groups (groups 2, 3, and 4). Group 1 was maintained as an unfilled control, and tooth ash and plaster of Paris were used in group 2, tooth ash and plaster of Paris with PRP were used in group 3, and tooth ash and plaster of Paris with fibrin sealant (Tissucol Duo Quick) were used in group 4. One-half of the animals were killed after 4 weeks, and the rest were killed after 8 weeks. Bone samples were taken from the defect areas, and newly formed bone was analyzed histomorphometrically. RESULTS: The rate of new bone formation in groups 2, 3, and 4 was significantly higher than the rate in the control group. The rate of new bone formation in groups 3 and 4 was higher than the rate in group 2, but the difference was not statistically significant. CONCLUSION: The concomitant use of PRP or fibrin sealant with tooth ash and plaster of Paris graft materials may have a positive effect on bone healing.


Assuntos
Substitutos Ósseos/farmacologia , Adesivo Tecidual de Fibrina/farmacologia , Minerais/farmacologia , Osteogênese/efeitos dos fármacos , Plasma Rico em Plaquetas , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Sulfato de Cálcio/química , Sulfato de Cálcio/farmacologia , Misturas Complexas/química , Misturas Complexas/farmacologia , Combinação de Medicamentos , Feminino , Hidroxiapatitas/química , Hidroxiapatitas/farmacologia , Implantes Experimentais , Masculino , Minerais/química , Osseointegração/efeitos dos fármacos , Coelhos , Crânio/efeitos dos fármacos , Crânio/cirurgia , Dente/química
12.
Opt Express ; 17(18): 15502-7, 2009 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-19724547

RESUMO

We will discuss fabrication of twin core photonic crystal fiber (TC-PCF) using the stack-and-draw method and its application for in-line Mach-Zehnder interferometers. The small difference in the effective indexes of the two core modes leads to interference fringes and the birefringence of the twin cores results in polarization-dependent fringe spacing. The strain sensitivity was negative and wavelength-dependent. A novel intensity-based bend sensor is also demonstrated with bend-induced spatial fringe shift. High air filling fraction of fabricated TC-PCF cladding provides immunity to bend-induced intensity fluctuation.

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