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1.
Chemistry ; : e202402163, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949770

RESUMO

Gases are essential for various applications relevant to human health, including in medicine, biomedical imaging, and pharmaceutical synthesis. However, gases are significantly more challenging to safely handle than liquids and solids. Herein, we review the use of porous materials, such as metal-organic frameworks (MOFs), zeolites, and silicas, to adsorb medicinally relevant gases and facilitate their handling as solids. Specific topics include the use of MOFs and zeolites to deliver H2S for therapeutic applications, 129Xe for magnetic resonance imaging, O2 for the treatment of cancer and hypoxia, and various gases for use in organic synthesis. This Perspective aims to bring together the organic, inorganic, medicinal, and materials chemistry communities to inspire the design of next-generation porous materials for the storage and delivery of medicinally relevant gases.

2.
Biology (Basel) ; 13(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38666879

RESUMO

Pumpkins (Cucurbita moschata), valued for their nutritional, medicinal, and economic significance, face threats from Meloidogyne incognita, a critical plant-parasitic nematode. This study extensively examines the impact of M. incognita on the growth, physiological, and biochemical responses of C. moschata. We demonstrate that M. incognita infection leads to significant growth impairment in C. moschata, evidenced by reduced plant height and biomass, along with the significant development of nematode-induced galls. Concurrently, a pronounced oxidative stress response was observed, characterized by elevated levels of hydrogen peroxide and a significant increase in antioxidant defense mechanisms, including the upregulation of key antioxidative enzymes (superoxide dismutase, glutathione reductase, catalase, and peroxidase) and the accumulation of glutathione. These responses highlight a dynamic interaction between the plant and the nematode, wherein C. moschata activates a robust antioxidant defense to mitigate the oxidative stress induced by nematode infection. Despite these defenses, the persistence of growth impairment underscores the challenge posed by M. incognita to the agricultural production of C. moschata. Our findings contribute to the understanding of plant-nematode interactions, paving the way for the development of strategies aimed at enhancing resistance in Cucurbitaceae crops against nematode pests, thus supporting sustainable agricultural practices.

3.
CrystEngComm ; 24(41): 7292-7297, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36776537

RESUMO

Metal-organic frameworks bearing coordinatively unsaturated Mg(II) sites are promising materials for gas storage, chemical separations, and drug delivery due to their low molecular weights and lack of toxicity. However, there remains a limited number of such MOFs reported in the literature. Herein, we investigate the gas sorption properties of the understudied framework Mg2(m-dobdc) (dobdc4- = 4,6-dioxido-1,3-benzenedicarboxylate) synthesized under both solvothermal and mechanochemical conditions. Both materials are found to be permanently porous, as confirmed by 77 K N2 adsorption measurements. In particular, Mg2(m-dobdc) synthesized under mechanochemical conditions using exogenous organic base displays one of the highest capacities reported to date (6.14 mmol/g) for CO2 capture in a porous solid under simulated coal flue gas conditions (150 mbar, 40 °C). As such, mechanochemically synthesized Mg2(m-dobdc) represents a promising new framework for applications requiring high gas adsorption capacities in a porous solid.

4.
Phytopathology ; 111(10): 1800-1810, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33703920

RESUMO

Bananas are among the world's most important cash and staple crops but are threatened by various devastating pathogens. The phytohormone salicylic acid (SA) plays a key role in the regulation of plant immune response. Tracking the expression of SA-responsive marker genes under pathogen infection is important in pathogenesis elucidation. However, the common SA-responsive marker genes are not consistently induced in different banana cultivars or different organs. Here, we conducted transcriptome analysis for SA response of a banana cultivar, 'Pei-Chiao' (Cavendish, AAA genome), and identified three genes, MaWRKY40, MaWRKY70, and Downy Mildew Resistant 6 (DMR6)-Like Oxygenase 1 (MaDLO1) that are robustly induced upon SA treatment in both the leaves and roots. Consistent induction of these three genes by SA treatment was also detected in both the leaves and roots of bananas belonging to different genome types such as 'Tai-Chiao No. 7' (Cavendish, AAA genome), 'Pisang Awak' (ABB genome), and 'Lady Finger' (AA genome). Furthermore, the biotrophic pathogen cucumber mosaic virus elicited the expression of MaWRKY40 and MaDLO1 in infected leaves of susceptible cultivars. The hemibiotrophic fungal pathogen Fusarium oxysporum f. sp. cubense tropical race 4 (TR4) also consistently induced the expression of MaWRKY40 and MaDLO1 in the infected roots of the F. oxysporum f. sp. cubense TR4-resistant cultivar. These results indicate that MaWRKY40 and MaDLO1 can be used as reliable SA-responsive marker genes for the study of plant immunity in banana. Revealing SA-responsive marker genes provides a stepping stone for further studies in banana resistance to pathogens.


Assuntos
Musa , Produtos Agrícolas , Imunidade , Musa/genética , Doenças das Plantas , Ácido Salicílico
5.
J Orthop Res ; 37(8): 1784-1789, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30977552

RESUMO

Legg-Calve-Perthes disease is characterized by the capital femoral epiphyseal collapse, which occurs more reliably in the anterior quadrant than the more weight-bearing lateral quadrant. The purpose of this study was to determine whether there is a vascular or microstructural predisposition for anterior femoral epiphyseal collapse in Perthes disease. Thirty-two cadaveric proximal femoral epiphyses from 17 subjects (age 4-14 years old) underwent micro-computed tomography at 10-µm resolution. Each quadrant was analyzed for four markers of trabecular architecture: bone volume fraction (BV/TV), trabecular thickness, trabecular separation (TbSp), and trabecular number (TbN). Vascular channels were then mapped in each quadrant, identified by correlating surface topography with cross-sectional imaging. One-way analysis of variance revealed an overall difference between quadrants (p < 0.001) in BV/TV, TbN, and TbSp. However, post hoc analysis revealed there was no significant difference between the anterior and lateral quadrants for any of the four markers of trabecular architecture. Vascular channel mapping illustrated a predominance of vessels in the posterior half of the epiphysis compared to the anterior half (8.7 ± 4.0 vs. 3.4 ± 3.1 vascular channels, p < 0.001). The lack of microstructural differences between the anterior and lateral quadrants, and the predominance of vascular channels in the posterior half of the epiphysis with posteriorly-based medial femoral circumflex and ligamentum teres vessels suggests that the anterior femoral epiphysis may be a relative vascular watershed region, which predisposes it to collapse after the vascular insult of Perthes disease. Clinical significance: Improved understanding of the pathophysiology of anterior femoral epiphyseal collapse may inform future treatments aimed at revascularization. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1784-1789, 2019.


Assuntos
Osso Esponjoso/patologia , Fêmur/patologia , Doença de Legg-Calve-Perthes/patologia , Adolescente , Osso Esponjoso/irrigação sanguínea , Osso Esponjoso/diagnóstico por imagem , Criança , Pré-Escolar , Epífises/irrigação sanguínea , Epífises/diagnóstico por imagem , Epífises/patologia , Feminino , Fêmur/irrigação sanguínea , Fêmur/diagnóstico por imagem , Humanos , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Masculino , Microtomografia por Raio-X
6.
Pediatrics ; 142(6)2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30385640

RESUMO

: media-1vid110.1542/5839992674001PEDS-VA_2018-1485Video Abstract BACKGROUND AND OBJECTIVES: Recently, the Neonatal Resuscitation Program (NRP) recommended against routine endotracheal suctioning of meconium-stained nonvigorous newborns but suggested resuscitation with positive pressure ventilation. Our purpose is to study the effects of this change in management. METHODS: In this multicenter cohort study, we compare 130 nonvigorous newborns born during the retrospective 1-year period before the implementation of new NRP guidelines (October 1, 2015, to September 30, 2016) to 101 infants born during the 1-year prospective period after implementation (October 1, 2016, to September 30, 2017). RESULTS: Endotracheal suctioning was performed predominantly in the retrospective group compared with the prospective group (70% vs 2%), indicating the change in practice. A significantly higher proportion of newborns were admitted to the NICU for respiratory issues in the prospective group compared with the retrospective group (40% vs 22%) with an odds ratio (OR) of 2.2 (95% confidence interval [CI]: 1.2-3.9). Similarly, a significantly higher proportion of infants needed oxygen therapy (37% vs 19%) with an OR of 2.5 (95% CI: 1.2-4.5), mechanical ventilation (19% vs 9%) with an OR of 2.6 (95% CI: 1.1-5.8), and surfactant therapy (10% vs 2%) with an OR of 5.8 (95% CI: 1.5-21.8). There were no differences in the incidence of other outcomes, including meconium aspiration syndrome. CONCLUSIONS: The recent NRP guideline change was not associated with an increased incidence of meconium aspiration syndrome but was associated with an increased incidence of NICU admissions for respiratory issues. Also, the need for mechanical ventilation, oxygen, and surfactant therapy increased.


Assuntos
Salas de Parto , Gerenciamento Clínico , Doenças do Recém-Nascido/terapia , Síndrome de Aspiração de Mecônio/terapia , Respiração Artificial/métodos , Ressuscitação/métodos , Adulto , Feminino , Seguimentos , Humanos , Recém-Nascido , Intubação Intratraqueal , Masculino , Gravidez , Estudos Retrospectivos , Sucção/métodos
7.
Molecules ; 23(12)2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30486478

RESUMO

The root of Chinese sage (Salvia miltiorrhiza Bunge) was regarded as top-grade Chinese medicine two thousand years ago, according to Shen Nong Materia Medica. The aim of this study is to develop an easy and reliable means for obtaining tetraploids (4x plants) via thidiazuron-induced direct organogenesis in the presence of colchicine. The resulting 4x plants showed significantly enhanced agronomic traits, including the size of stomata, leaflet, pollen, and seed as well as shoot length, root diameter, number of leaves, and fresh weight of plant. In addition, an obvious reduction of length to width ratio was found in the 4x plants, including stomata, leaflets, pollens, seeds, and roots. The 4x ploidy state of the plants was stable as was proved by evaluation of selection indicators as well as consistent ploidy level at 10th generation plantlets and also on 4x seedlings obtained via self-pollination. The major bioactive compounds, salvianolic acid B, tanshinone I, tanshinone IIA, dihydrotanshinone I and cryptotanshinone, as well as total tanshinones were determined by high performance liquid chromatography (HPLC). The concentrations of dihydrotanshinone I and total tanshinones in the root extract of the 4x plants were significantly higher when compared with the 2x plants. This present study developed a simple and efficient system for inducing and subculture of tetrapolids which have stable ploidy level, enhanced growth characteristics as well as the content of dihydrotanshinone I in the root of S. miltiorrhiza.


Assuntos
Biomassa , Cromossomos de Plantas/genética , Medicina Tradicional Chinesa , Plantas Medicinais , Salvia miltiorrhiza , Tetraploidia , Cromossomos de Plantas/metabolismo , Colchicina/farmacologia , Compostos de Fenilureia/farmacologia , Plantas Medicinais/genética , Plantas Medicinais/crescimento & desenvolvimento , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/crescimento & desenvolvimento , Tiadiazóis/farmacologia
8.
Bone ; 116: 221-231, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30125727

RESUMO

Legg-Calvé-Perthes disease (LCPD) is a childhood form of ischemic osteonecrosis of the femoral head which can produce a permanent femoral head deformity and early osteoarthritis. The femoral head deformity results from increased bone resorption and decreased bone formation during repair and remodeling of the necrotic femoral head. A recent study showed that a pro-inflammatory cytokine, interleukin-6 (IL-6), is significantly elevated in the synovial fluid of patients with LCPD. We hypothesized that IL-6 elevation decreases bone formation during the repair process following ischemic osteonecrosis and that IL-6 depletion will increase new bone formation. To test this hypothesis, we surgically induced ischemic osteonecrosis in the wild-type (n = 29) and IL-6 knockout (KO) mice (n = 25). The animals were assessed at 48 h, 2 weeks and 4 weeks following the induction of ischemic osteonecrosis using histologic, histomorphometric and micro-CT methods. IL-6 immunohistochemistry showed high expression of IL-6 in the osteonecrotic side of the wild-type mice at 48 h and 4 weeks following ischemic osteonecrosis, but not in the IL-6 KO mice. We also confirmed an undetectable level of IL-6 expression in the primary osteoblasts of the IL-6 KO mice compared to the readily detectable level in the wild-type mice. Furthermore, we confirmed that IL-6 deletion did not affect the extent of bone necrosis in the IL-6 KO mice compared to the wild-type mice by performing histologic and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assessments at 2 weeks following the induction of ischemia. Both groups had the same extent of ischemic osteonecrosis and absence of repair at 2 weeks. At 4 weeks, the necrotic epiphyses showed a significant increase in the extent of revascularization in the IL-6 KO mice compared to the wild-type mice (p = 0.001). In addition, a significantly greater recovery of the hematopoietic bone marrow was observed in the osteonecrotic side of the IL-6 KO mice compared to the wild-type mice (p < 0.01). Vascular endothelial growth factor (VEGF) immunohistochemistry showed regionally increased staining in the areas of repair in the osteonecrosis side of IL-6 KO mice compared to the wild-type mice at 4 weeks following ischemic osteonecrosis. Micro-CT assessment of the wild-type mice at 4 weeks showed a significant decrease in the percent bone volume (p < 0.01) in the osteonecrotic side compared to the control side. In contrast, IL-6 KO mice showed significantly increased bone volume in the osteonecrotic side compared to the osteonecrotic side of WT mice (p < 0.001). No significant difference in the bone volume percentage was found between the control side of the wild-type and the IL-6 KO mice. Histomorphometric analysis at 4 weeks revealed increased osteoblast number/bone surface (p < 0.001), bone formation rate (BFR) (p = 0.0001), and mineral apposition rate (MAR) (p < 0.0001) in the osteonecrotic side of the IL-6 KO mice compared to the wild-type mice. The number of osteoclast/bone surface was also increased in the IL-6 KO mice compared to the wild-type mice (p < 0.0001). No significant difference was observed between the control side of the wild-type and IL-6 KO mice with regards to the number of osteoblast or osteoclast/bone surface, BFR, and MAR. We next obtained primary osteoblasts from IL-6 KO mice and showed they expressed a significantly higher level of RANKL/OPG than wild-type mice (p = 0.001) in hypoxia culture condition. Taken together, the findings indicate that IL-6 deletion stimulates revascularization and new bone formation following ischemic osteonecrosis. This study provides new evidence that therapeutic strategies to block IL-6 may be beneficial for bone healing following ischemic osteonecrosis.


Assuntos
Necrose da Cabeça do Fêmur/patologia , Cabeça do Fêmur/irrigação sanguínea , Deleção de Genes , Interleucina-6/deficiência , Isquemia/patologia , Neovascularização Fisiológica , Osteogênese , Animais , Células Cultivadas , Modelos Animais de Doenças , Epífises/diagnóstico por imagem , Epífises/patologia , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/fisiopatologia , Necrose da Cabeça do Fêmur/cirurgia , Hematopoese , Interleucina-6/genética , Isquemia/complicações , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoclastos/metabolismo , Osteoclastos/patologia , Fenótipo , Reprodutibilidade dos Testes , Microtomografia por Raio-X
9.
J Bone Miner Res ; 30(6): 1009-13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25556551

RESUMO

Legg-Calvé-Perthes disease (LCPD) is a childhood hip disorder of ischemic osteonecrosis of the femoral head. Hip joint synovitis is a common feature of LCPD, but the nature and pathophysiology of the synovitis remain unknown. The purpose of this study was to determine the chronicity of the synovitis and the inflammatory cytokines present in the synovial fluid at an active stage of LCPD. Serial MRI was performed on 28 patients. T2-weighted and gadolinium-enhanced MR images were used to assess synovial effusion and synovial enhancement (hyperemia) over time. A multiple-cytokine assay was used to determine the levels of 27 inflammatory cytokines and related factors present in the synovial fluid from 13 patients. MRI analysis showed fold increases of 5.0 ± 3.3 and 3.1 ± 2.1 in the synovial fluid volume in the affected hip compared to the unaffected hip at the initial and the last follow-up MRI, respectively. The mean duration between the initial and the last MRI was 17.7 ± 8.3 months. The volume of enhanced synovium on the contrast MRI was increased 16.5 ± 8.5 fold and 6.3 ± 5.6 fold in the affected hip compared to the unaffected hip at the initial MRI and the last follow-up MRI, respectively. In the synovial fluid of the affected hips, IL-6 protein levels were significantly increased (LCPD: 509 ± 519 pg/mL, non-LCPD: 19 ± 22 pg/mL; p = 0.0005) on the multi-cytokine assay. Interestingly, IL-1ß and TNF-α levels were not elevated. In the active stage of LCPD, chronic hip synovitis and significant elevation of IL-6 are produced in the synovial fluid. Further studies are warranted to investigate the role of IL-6 on the pathophysiology of synovitis in LCPD and how it affects bone healing.


Assuntos
Articulação do Quadril/metabolismo , Interleucina-6/metabolismo , Doença de Legg-Calve-Perthes/metabolismo , Líquido Sinovial/metabolismo , Sinovite/metabolismo , Feminino , Articulação do Quadril/diagnóstico por imagem , Humanos , Interleucina-1beta/metabolismo , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Masculino , Radiografia , Sinovite/diagnóstico por imagem , Fator de Necrose Tumoral alfa/metabolismo
10.
J Bone Joint Surg Am ; 96(14): 1152-1160, 2014 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-25031369

RESUMO

BACKGROUND: Current radiographic classifications for Legg-Calvé-Perthes disease cannot be applied at the early stages of the disease. The purpose of this study was to quantify the perfusion of the femoral epiphysis in the early stages of Legg-Calvé-Perthes disease with use of perfusion magnetic resonance imaging (MRI) and to determine if the extent of epiphyseal perfusion can predict the lateral pillar involvement at the mid-fragmentation stage. METHODS: Twenty-nine patients had gadolinium-enhanced perfusion MRI at the initial stage or early fragmentation stage of Legg-Calvé-Perthes disease and were followed prospectively. The percent perfusion of the whole epiphysis and its lateral third was measured by four independent observers using image analysis software. The radiographs obtained at the mid-fragmentation stage were used for the lateral pillar classification. Intraclass correlation coefficient (ICC) and logistic regression analyses were performed. RESULTS: The mean age (and standard deviation) at diagnosis was 7.7 ± 1.7 years (range, 5.3 to 11.3 years). The mean interval between the MRI and the time of maximum fragmentation was 8.2 ± 5.5 months. The interobserver ICC for the percent perfusion of the lateral third of the epiphysis was 0.90 (95% confidence interval [CI]: 0.83 to 0.95). The mean percent perfusion of the lateral third of the epiphysis was 92% ± 2%, 68% ± 18%, and 46% ± 12% for the hips in which the lateral pillar was later classified as A, B, and C, respectively (p = 0.001). When the perfusion level was ≥90% in the lateral third of the epiphysis, the odds ratio of the lateral pillar being later classified as group A, as opposed to B or C, was 72.0 (CI: 3.5 to 1476). With a perfusion level of ≤55% in the lateral third of the epiphysis, the odds ratio of the lateral pillar being later classified as group C, as opposed to A or B, was 33.3 (CI: 2.8 to 392). Similar results were obtained for the whole epiphysis. CONCLUSIONS: Perfusion MRI measurements of the total epiphysis and its lateral third obtained at the early stages of Legg-Calvé-Perthes disease were predictive of lateral pillar involvement at the mid-fragmentation stage of the disease. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Cabeça do Fêmur/diagnóstico por imagem , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Angiografia por Ressonância Magnética , Criança , Pré-Escolar , Epífises/diagnóstico por imagem , Feminino , Cabeça do Fêmur/patologia , Humanos , Doença de Legg-Calve-Perthes/complicações , Doença de Legg-Calve-Perthes/patologia , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos
11.
Anal Chem ; 81(8): 2944-52, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19296592

RESUMO

A rapid and sensitive method to detect single-walled carbon nanotubes (SWNTs) in biological samples is presented. The method uses polyacrylamide gel electrophoresis (PAGE) followed by quantification of SWNT bands. SWNTs dispersed in bovine serum albumin (BSA) were used to develop the method. When BSA-SWNT dispersions were subjected to sodium dodecyl sulfate (SDS)-PAGE, BSA passed through the stacking gel, entered the resolving gel, and migrated toward the anode as expected. The SWNTs, however, accumulated in a sharp band at the interface between the loading well and the stacking gel. The intensities from digitized images of these bands were proportional to the amount of SWNTs loaded onto the gel with a detection limit of 5 ng of SWNTs. To test the method, normal rat kidney (NRK) cells in culture were allowed to take up SWNTs upon exposure to medium containing various concentrations of BSA-SWNTs for different times and temperatures. The SDS-PAGE analyses of cell lysate samples suggest that BSA-SWNTs enter NRK cells by fluid-phase endocytosis at a rate of 30 fg/day/cell upon exposure to medium containing 98 microg/mL SWNTs.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Nanotubos de Carbono/análise , Absorção , Animais , Transporte Biológico , Bovinos , Rim/citologia , Rim/metabolismo , Ratos , Soroalbumina Bovina/metabolismo , Análise Espectral Raman
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