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1.
Artigo em Inglês | MEDLINE | ID: mdl-39017815

RESUMO

PURPOSE: CD133, a cancer stem cells (CSC) marker, has been reported to be associated with treatment resistance and worse survival in triple-negative breast cancer (BC). However, the clinical relevance of CD133 expression in ER-positive/HER2-negative (ER + /HER2-) BC, the most abundant subtype, remains unknown. METHODS: The BC cohorts from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC, n = 1904) and The Cancer Genome Atlas (TCGA, n = 1065) were used to obtain biological variables and gene expression data. RESULTS: Epithelial cells were the exclusive source of CD133 gene expression in a bulk BC. CD133-high ER + /HER2- BC was associated with CD24, NOTCH1, DLL1, and ALDH1A1 gene expressions, as well as with WNT/ß-Catenin, Hedgehog, and Notch signaling pathways, all characteristic for CSC. Consistent with a CSC phenotype, CD133-low BC was enriched with gene sets related to cell proliferation, such as G2M Checkpoint, MYC Targets V1, E2F Targets, and Ki67 gene expression. CD133-low BC was also linked with enrichment of genes related to DNA repair, such as BRCA1, E2F1, E2F4, CDK1/2. On the other hand, CD133-high tumors had proinflammatory microenvironment, higher activity of immune cells, and higher expression of genes related to inflammation and immune response. Finally, CD133-high tumors had better pathological complete response after neoadjuvant chemotherapy in GSE25066 cohort and better disease-free survival and overall survival in both TCGA and METABRIC cohorts. CONCLUSION: CD133-high ER + /HER2- BC was associated with CSC phenotype such as less cell proliferation and DNA repair, but also with enhanced inflammation, better response to neoadjuvant chemotherapy and better prognosis.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38972017

RESUMO

PURPOSE: While comprehensive research exists on the mutation of the DNA repair gene BRCA1, limited information is available regarding the clinical significance of BRCA1 gene expression. Given that cancer cell proliferation is aggrevated by DNA repair, we hypothesized that high BRCA1 gene expression breast cancer (BC) might be linked with aggressive tumor biology and poor clinical outcomes. METHODS: The cohorts: The Cancer Genome Atlas (TCGA, n = 1069), METABRIC (n = 1903), and SCAN-B (n = 3273) were utilzed to obtain data of 6245 BC patients. RESULTS: BC patients without BRCA1 mutation exhibited higher BRCA1 expression, which was associated with DNA repair functionality. However, no such correlation was observed with BRCA2 expression. The association of high BRCA1 expression with cancer cell proliferation was evidenced by significant enrichment of cell proliferation-related gene sets, higher histological grade, and proliferation score. Furthermore, increased levels of homologous recombination deficiency, intratumoral heterogeneity, and altered fractions were associated with high BRCA1 expression. Moreover, BC with high BRCA1 expression exhibited reduced infiltration of dendritic cells and CD8 T-cells, while showing increased infiltration of Th1 cells. Surprisingly, BRCA1 expression was not associated with the survival of BC irrespective of the subtypes. Conversely, BC with low BRCA1 expression enriched cancer aggravating pathway gene sets, such as Cancer Stem Cell-related signaling (NOTCH and HEDGEHOG), Angiogenesis, Epithelial-Mesenchymal Transition, Inflammatory Response, and TGF-beta signaling. CONCLUSION: Despite being linked to heightened proliferation of cancer cells and unassertive phenotype, BRCA1 expression did not show any association with survival in BC.

3.
Langmuir ; 40(15): 7962-7973, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38577710

RESUMO

During the manufacturing process of liposome formulations, it is considered difficult to evaluate their physicochemical properties and biological profiles due to the complexity of their structure and manufacturing process. Conventional quality evaluation is labor-intensive and time-consuming; therefore, there was a need to introduce a method that could perform in-line, real-time evaluation during the manufacturing process. In this study, Raman spectroscopy was used to monitor in real time the encapsulation of drugs into liposomes and the drug release, which are particularly important quality evaluation items. Furthermore, Raman spectroscopy combined with partial least-squares (PLS) analysis was used for quantitative drug evaluation to assess consistency with results from UV-visible spectrophotometry (UV), a common quantification method. The prepared various ciprofloxacin (CPFX) liposomes were placed in cellulose tubes, and a probe-type Raman spectrophotometer was used to monitor drug encapsulation, the removal of unencapsulated drug, and drug release characteristics in real time using a dialysis method. In the Raman spectra of the liposomes prepared by remote loading, the intensities of the CPFX-derived peaks increased upon drug encapsulation and showed a slight decrease upon removal of the unencapsulated drug. Furthermore, the peak intensity decreased more gradually during the drug release. In all Raman monitoring experiments, the discrepancy between quantified values of CPFX concentration in liposomes, as measured by Raman spectroscopy combined with partial least-squares (PLS) analysis, and those obtained through ultraviolet (UV) spectrophotometry was within 6.7%. The results revealed that the quantitative evaluation of drugs using a combination of Raman spectroscopy and PLS analysis was as accurate as the evaluation using UV spectrophotometry, which was used for comparison. These results indicate the promising potential of Raman spectroscopy as an innovative method for the quality evaluation of liposomal formulations.


Assuntos
Celulose , Lipossomos , Composição de Medicamentos/métodos , Análise Espectral Raman/métodos
4.
J Nat Prod ; 87(6): 1556-1562, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38758599

RESUMO

Bis-indole alkaloids from marine sponges are an intriguing class of natural products with a variety of activities. However, only a preliminary biological study of tulongicin A (5), a related previously isolated marine tris-indole alkaloid, has been conducted. In this study, we accomplished the first asymmetric total synthesis of 5 via the construction of an imidazoline-linked bis-indolylmethane skeleton using a Friedel-Crafts-type reaction. Our synthesis enabled a detailed study of the antibacterial profile of 5. Compound 5 displayed bactericidal activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA) strains.


Assuntos
Antibacterianos , Alcaloides Indólicos , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Estrutura Molecular , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/síntese química , Alcaloides Indólicos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Staphylococcus aureus/efeitos dos fármacos , Poríferos/química , Biologia Marinha
5.
Rinsho Ketsueki ; 65(4): 231-236, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38684432

RESUMO

A 69-year-old woman was referred to our hospital due to hyperleukocytosis. We diagnosed acute myeloid leukemia and started induction therapy with the CAG regimen (aclarubicin, cytarabine and filgrastim). However, the patient was refractory to the initial treatment and developed quadriplegia, and a cerebrospinal fluid (CSF) test showed elevated blasts. We then performed intrathecal chemotherapy, and the number of blasts in CSF gradually decreased. But only two cycles of intrathecal therapy were possible due to severe methotrexate-induced mucositis. The leukemia cells had fms-like kinase 3-internal tandem duplication (FLT3-ITD), so we started treatment with oral gilteritinib. The patient then achieved hematological complete remission. Her paralysis was also resolving, and the CSF was clear of blasts for more than 6 months. Some reports show that gilteritinib may penetrate the CNS, and this case also supports the effectiveness of gilteritinib on CNS leukemia.


Assuntos
Compostos de Anilina , Leucemia Mieloide Aguda , Pirazinas , Humanos , Idoso , Feminino , Leucemia Mieloide Aguda/tratamento farmacológico , Pirazinas/administração & dosagem , Pirazinas/uso terapêutico , Compostos de Anilina/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Tirosina Quinase 3 Semelhante a fms , Resultado do Tratamento
6.
J Bone Miner Metab ; 41(6): 865-876, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37897670

RESUMO

INTRODUCTION: The present study developed an application using dual-energy computed tomography (DECT) focused on Cu for detecting medication-related osteonecrosis of the jaw (MRONJ). MATERIALS AND METHODS: First, we performed two types of phantom studies using a Cu wire syringe and pig mandible with Cu wire to detect Cu on DECT. Second, DECT examinations of 44 patients with MRONJ were performed to compare lesion and normal bone sites using single-energy CT, DECT-virtual non-calcium (VNCa), and DECT-Cu applications. Quantitative analyses of VNCa CT and CT values were performed, and a cut-off value was calculated using receiver operating characteristic analysis. Third, we compared the Cu content in the MRONJ and normal bone groups using inductively coupled plasma atomic emission spectroscopy (ICP-AES). RESULTS: The material-specific differences in attenuation between the two different energies enabled the accurate separation of Cu from Ca in phantom studies. The sensitivity and specificity for single-energy CT, DECT-VNCa, and DECT-Cu applications were 97.7% and 2.3%, 86.4% and 81.8%, and 88.6% and 97.7%, respectively. Thus, VNCa CT values obtained on DECT-Cu application images showed the highest area under the curve value and maximal diagnostic efficacy in differentiating lesion sites from normal bone sites. On ICP-AES analyses, the Cu content was significantly higher in the MRONJ group than in the normal bone group. CONCLUSION: DECT-Cu application demonstrated better diagnostic performance in detecting MRONJ compared with single-energy CT or DECT-VNCa.


Assuntos
Osteonecrose , Tomografia Computadorizada por Raios X , Humanos , Animais , Suínos , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade , Curva ROC , Osteonecrose/induzido quimicamente , Osteonecrose/diagnóstico por imagem , Cálcio da Dieta
7.
Proc Natl Acad Sci U S A ; 117(25): 14552-14560, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513689

RESUMO

Both inorganic fertilizer inputs and crop yields have increased globally, with the concurrent increase in the pollution of water bodies due to nitrogen leaching from soils. Designing agroecosystems that are environmentally friendly is urgently required. Since agroecosystems are highly complex and consist of entangled webs of interactions between plants, microbes, and soils, identifying critical components in crop production remain elusive. To understand the network structure in agroecosystems engineered by several farming methods, including environmentally friendly soil solarization, we utilized a multiomics approach on a field planted with Brassica rapa We found that the soil solarization increased plant shoot biomass irrespective of the type of fertilizer applied. Our multiomics and integrated informatics revealed complex interactions in the agroecosystem showing multiple network modules represented by plant traits heterogeneously associated with soil metabolites, minerals, and microbes. Unexpectedly, we identified soil organic nitrogen induced by soil solarization as one of the key components to increase crop yield. A germ-free plant in vitro assay and a pot experiment using arable soils confirmed that specific organic nitrogen, namely alanine and choline, directly increased plant biomass by acting as a nitrogen source and a biologically active compound. Thus, our study provides evidence at the agroecosystem level that organic nitrogen plays a key role in plant growth.


Assuntos
Brassica rapa/crescimento & desenvolvimento , Produção Agrícola , Produtos Agrícolas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Solo/química , Alanina/química , Alanina/metabolismo , Biomassa , Brassica rapa/metabolismo , Colina/química , Colina/metabolismo , Produtos Agrícolas/metabolismo , Conjuntos de Dados como Assunto , Redes e Vias Metabólicas/efeitos da radiação , Metabolômica , Microbiota/fisiologia , Microbiota/efeitos da radiação , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Rizosfera , Microbiologia do Solo , Luz Solar
8.
J Biol Chem ; 297(3): 100978, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34284062

RESUMO

Pregnane X receptor (PXR) plays an important role in xenobiotic metabolism. While ligand binding induces PXR-dependent gene transcription, PXR shows constitutive transcriptional activity in the absence of ligands when expressed in cultured cells. This constitutive activity sometimes hampers investigation of PXR activation by compounds of interest. In this study, we investigated the molecular mechanism of PXR activation. In the reported crystal structures of unliganded PXR, helix 12 (H12), including a coactivator binding motif, was stabilized, while it is destabilized in the unliganded structures of other nuclear receptors, suggesting a role for H12 stabilization in the basal activity of PXR. Since Phe420, located in the loop between H11 and H12, is thought to interact with Leu411 and Ile414 to stabilize H12, we substituted alanine at Phe420 (PXR-F420A) and separately inserted three alanine residues directly after Phe420 (PXR-3A) and investigated their influence on PXR-mediated transcription. Reporter gene assays demonstrated that the mutants showed drastically reduced basal activity and enhanced responses to various ligands, which was further enhanced by coexpression of the coactivator peroxisome proliferator-activated receptor gamma coactivator 1α. Mutations of both Leu411 and Ile414 to alanine also suppressed basal activity. Mammalian two-hybrid assays showed that PXR-F420A and PXR-3A bound to corepressors and coactivators in the absence and presence of ligands, respectively. We conclude that the intramolecular interactions of Phe420 with Leu411 and Ile414 stabilize H12 to recruit coactivators even in the absence of ligands, contributing to the basal transcriptional activity of PXR. We propose that the generated mutants might be useful for PXR ligand screening.


Assuntos
Receptor de Pregnano X/fisiologia , Transcrição Gênica/fisiologia , Animais , Células COS , Chlorocebus aethiops , Cristalografia por Raios X , Humanos , Ligantes , Mutação , Receptor de Pregnano X/antagonistas & inibidores , Receptor de Pregnano X/química , Receptor de Pregnano X/genética , Conformação Proteica , Técnicas do Sistema de Duplo-Híbrido
9.
Parasitology ; 149(1): 105-115, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35184787

RESUMO

Poultry red mites (Dermanyssus gallinae, PRM) are dangerous ectoparasites that infest chickens and threaten the poultry industry worldwide. PRMs usually develop resistance to chemical acaricides, necessitating the development of more effective preventive agents, and vaccination could be an alternative strategy for controlling PRMs. The suitability of plasma membrane proteins expressed in the midguts as vaccine antigens was evaluated because these molecules are exposed to antibodies in the ingested blood and the binding of antibodies could potentially induce direct damage to midgut tissue and indirect damage via inhibition of the functions of target molecules. Therefore, in the present study, a copper transporter 1-like molecule (Dg-Ctr1) was identified and its efficacy as a vaccine antigen was assessed in vitro. Dg-Ctr1 mRNA was expressed in the midguts and ovaries and in all the life stages, and flow cytometric analysis indicated that Dg-Ctr1 was expressed on the plasma membrane. Importantly, nymphs fed on plasma derived from chickens immunized with the recombinant protein of the extracellular region of Dg-Ctr1 showed a significant reduction in the survival rate. These data indicate that the application of Dg-Ctr1 as a vaccine antigen could reduce the number of nymphs in the farms, contributing to reduction in the economic losses caused by PRMs in the poultry industry. To establish an effective vaccination strategy, the acaricidal effects of the combined use of Dg-Ctr1 with chemical acaricides or other vaccine antigens must be examined.


Assuntos
Infestações por Ácaros , Ácaros , Doenças das Aves Domésticas , Vacinas , Animais , Galinhas/parasitologia , Transportador de Cobre 1 , Infestações por Ácaros/parasitologia , Infestações por Ácaros/prevenção & controle , Infestações por Ácaros/veterinária , Ácaros/genética , Doenças das Aves Domésticas/parasitologia
10.
Int J Mol Sci ; 23(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955941

RESUMO

Nanoparticles exhibit diverse self-assembly attributes and are expected to be applicable under unique settings. For instance, biomolecules can be sandwiched between dimer nanoparticles and detected by surface-enhanced Raman scattering. Controlling the gap between extremely close dimers and stably capturing the target molecule in the gap are crucial aspects of this strategy. Therefore, polymer-tethered nanoparticles (PTNPs), which show promise as high-performance materials that exhibit the attractive features of both NPs and polymers, were targeted in this study to achieve stable biomolecule sensing. Using coarse-grained molecular dynamics simulations, the dependence of the PTNP interactions on the length of the grafted polymer, graft density, and coverage ratio of a hydrophobic tether were examined. The results indicated that the smaller the tether length and graft density, the smaller was the distance between the PTNP surfaces (Rsurf). In contrast, Rsurf decreased as the coverage ratio of the hydrophobic surface (ϕ) increased. The sandwiching probability of the sensing target increased in proportion to the coverage ratio. At high ϕ values, the PTNPs aggregated into three or more particles, which hindered their sensing attributes. These results provide fundamental insight into the sensing applications of NPs and demonstrate the usefulness of PTNPs in sensing biomolecules.


Assuntos
Nanopartículas , Ácidos Nucleicos , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Nanopartículas/química , Polímeros/química
11.
Soft Matter ; 17(15): 4047-4058, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33725068

RESUMO

In this study, a coarse-grained molecular simulation was performed to investigate the morphologies and phase diagrams of self-assembled polymer-tethered nanoparticles (NPs) confined in nanotubes (NTs). Unlike ordinary NPs, polymer-tethered NPs have two distinct characteristic lengths, which are key factors that determine their self-assembly. Herein, two distinct types of NT walls and three types of polymer-tethered NPs were considered: hydrophilic and hydrophobic walls, and hydrophilic, hydrophobic, and Janus surfaces. First, the qualitative phase diagrams of the axial pressure, Pz, versus the ratio of the NT radius to the NP radius, L, were derived. The results revealed that diverse self-assembled morphologies, which are not formed in non-tethered NPs, were observed in the polymer-tethered NPs. For example, three types of ordered structures with different structural characteristic lengths, depending on Pz, were obtained. In addition, the effect of the chemical nature of the polymer-tethered NP surface on the self-assembled morphology confined in NTs was investigated. Clusters of water molecules were formed, particularly in the hydrophobic polymer-tethered NPs, and these clusters caused the structural distortion of the NP. Moreover, in the polymer-tethered NPs with the Janus amphiphilic surface, the hydrophobic and hydrophilic polymer tethered NPs assembled in the axial direction to form an ordered structure, and a double-helix structure was formed at L = 3.0 in the hydrophobic NT. The results of these simulations indicate that the self-assembly behaviours of polymer-tethered NPs can be qualitatively predicted based on the chemical nature of the NT walls and the surface design of the polymer-tethered NP.

12.
Mycorrhiza ; 31(3): 403-412, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33459866

RESUMO

Arbuscular mycorrhizal (AM) fungal extraradical hyphae exude their metabolites into the soil. Root exudate metabolites are affected by plant species and P status. However, the effect of P status on AM hyphal exudate metabolites has been unknown. This study aimed to examine hyphal exudate metabolite composition of two AM fungal species and their response to P deficiency through metabolite profiling. Rhizophagus clarus and R. irregularis were grown in a two-compartment in vitro culture system of Linum usitatissimum roots on solid modified Strullu-Romand medium in combination with two P levels (3 µM (P3) and 30 µM (P30)). Hyphal exudates were collected from the hyphal compartment at 118 days after inoculation (DAI). The metabolite composition of the hyphal exudates was determined by capillary electrophoresis/time-of-flight mass spectrometry, resulting in the identification of a total of 141 metabolites at 118 DAI. In the hyphal exudates of R. clarus, the concentrations of 18 metabolites, including sugars, amino acids, and organic acids, were significantly higher (p < 0.05) under P3 than under P30 conditions. In contrast, the concentrations of 10 metabolites, including sugar and amino acids, in the hyphal exudates of R. irregularis were significantly lower (p < 0.05) under P3 than under P30 conditions. These findings suggest that the extraradical hyphae of AM fungi exude diverse metabolites of which concentrations are affected by P conditions and differ between AM fungal species.


Assuntos
Glomeromycota , Micorrizas , Exsudatos e Transudatos , Fungos , Hifas , Fósforo , Raízes de Plantas
13.
J Infect Chemother ; 25(1): 28-33, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30396822

RESUMO

Pseudomonas aeruginosa is one of the most common causes of nosocomial infections, and its multi-drug resistance has been a serious problem worldwide. The aim of this study was to evaluate whether exposure to piperacillin and reactive oxygen species (ROS) could lead to multi-drug resistance for clinical isolates of P. aeruginosa. The inhibition of this acquired resistance by the anti-ROS agent was also examined. In vitro inducement of multi-drug resistance was performed against 20 clinical isolates. These strains were incubated for 24 h and transferred 5 times after being exposed to 1 mM H2O2 (ROS) in addition to a sub-MIC of piperacillin by the agar dilution method. Each MIC of piperacillin and levofloxacin was determined. As the mechanism of levofloxacin resistance, mutation of QRDR was investigated. The expression level of genes encoding efflux pumps; mexA, mexY, mexC, and D2 porin; oprD were determined by real-time PCR. Multi-resistance to both piperacillin and levofloxacin was induced with 4 of 20 strains (20%). No amino acid change was confirmed in QRDR. These strains showed overexpression of mexA, mexY, mexC, and another one showed decrease of oprD expression. Resistance development in 4 strains was inhibited by the same method including the anti-ROS agent, sodium zinc histidine dithiooctanamide (DHL-His-Zn). In conclusion, stimulation by ROS promoted acquisition of multi-drug resistance in 20% of isolates of P. aeruginosa, and DHL-His-Zn completely inhibited this acquisition of resistance. Therefore, this anti-ROS agent may be useful to assist antimicrobial chemotherapy by preventing multi-drug resistance.


Assuntos
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Histidina/análogos & derivados , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Ácido Tióctico/análogos & derivados , Ácido Tióctico/farmacologia , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Histidina/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Levofloxacino/farmacologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Piperacilina/farmacologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
15.
Mycorrhiza ; 29(6): 599-605, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31745622

RESUMO

Arbuscular mycorrhizal (AM) fungi increase phosphate (P) uptake by plants. Organic phosphate comprises 30-80% of total P in most agricultural soils. Some plants can utilize organic phosphate by secreting acid phosphatase (ACP) from their roots, especially under low P conditions. Although secretion of ACP from extraradical hyphae of AM fungi has been reported, the specific factors that affect the secretion of ACP are unknown. The objective of the present study was to investigate whether secretion of ACP from extraradical hyphae is induced by low P conditions. First, specimens of Allium fistulosum were either inoculated with the AM fungus Rhizophagus clarus strain CK001 or remained uninoculated and were grown in soil with 0.5 g P2O5 kg-1 soil or without P fertilization using two-compartment pots. Soil solution was collected using mullite ceramic tubes 45 days after sowing. The soil solution was analyzed for ACP activity by using p-nitrophenylphosphate. Second, Ri T-DNA transformed roots (i.e., hairy roots) of Linum usitatissimum inoculated with R. clarus were grown on solid minimal media with two P levels applied (3 and 30 µM P) using two-compartment Petri dishes under in vitro conditions. Hyphal exudates, extraradical hyphae, and hairy roots were collected and analyzed for ACP activity. ACP activity in the soil solution of the hyphal compartment in the A. fistulosum inoculation treatment was higher without P fertilization than with P fertilization. AM colonization also was higher without P fertilization than with P fertilization. In the in vitro two-compartment culture, ACP activity of hyphal exudates and extraradical hyphae were higher under the 3-µM treatment than under the 30-µM treatment. These findings suggest that the secretion of ACP from the extraradical hyphae of R. clarus into the hyphosphere is promoted under low P conditions.


Assuntos
Micorrizas , Fosfatase Ácida , Hifas , Organofosfatos , Fosfatos , Raízes de Plantas
16.
Appl Opt ; 57(6): 1450-1454, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29469847

RESUMO

We report on the demonstration of Doppler-free spectroscopy of metastable Sr atoms using a hollow cathode lamp (HCL). We employed a custom Sr HCL, which is filled with a mixture of 0.5 Torr Ne and 0.5 Torr Xe as a buffer gas to suppress velocity changing collisions and increase the populations in all of the (5s5p)3PJ(J=0,1,2) metastable states. We performed frequency modulation spectroscopy for the (5s5p)3P0-(5s6s)3S1, (5s5p)3P1-(5s6s)3S1, (5s5p)3P2-(5s5d)3D2, and (5s5p)3P2-(5s5d)3D3 transitions with sufficient signal-to-noise ratios for laser frequency stabilization. We also observed the hyperfine transitions of (5s5p)3P2-(5s5d)3D3 of Sr87. This method would greatly facilitate laser cooling of Sr.

17.
Appl Opt ; 57(1): 52-56, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29328113

RESUMO

Characteristics of a diffusion-bonded sapphire cell for optical experiments with hot metal vapors were investigated. The sapphire cell consisted of sapphire-crystal plates and a borosilicate-glass tube, which were bonded to each other by diffusion bonding without any binders or glues. The glass tube was attached to a vacuum manifold using the standard method applied in glass processing, filled with a small amount of Rb metal by chasing with a torch, and then sealed. The cell was baked at high temperatures, and optical experiments were then performed using rubidium atoms at room temperature. The sapphire cell was found to be vacuum tight, at least up to 350°C, and the sapphire walls remained clear over all temperatures. From the optical experiments, the generation of a background gas was indicated after baking at 200°C. The background gas pressure was low enough to avoid pressure broadening of absorption lines but high enough to cause velocity-changing collisions of Rb atoms. The generated gas pressure decreased at higher temperatures, probably due to chemical reactions.

18.
Appl Opt ; 57(20): 5872-5883, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30118060

RESUMO

Effects of different parameters regarding partial least squares (PLS) regression analysis are investigated for quantitative analysis of water-submerged brass samples. The concentrations of Cu and Zn in various brass alloys were quantified using PLS, and the performance after different signal processing steps (normalization, smoothing, and background subtraction) and database segmentation by excitation temperature is compared. In addition, the effects of averaging numbers on the results are examined. From the results, normalization was found to be the most effective among three established signal processing methods. The effects of both peak and background fluctuations seen in the signals are reduced by normalization. It was found that temperature segmentation of the database in an appropriate range, which should be high enough for reliable peak detection, can further improve the accuracy of PLS calculations. The proposed method is applicable in real time, and can potentially be used for automated fast and accurate measurements of solids at oceanic pressures.

19.
J Infect Chemother ; 24(2): 83-87, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29290527

RESUMO

Community-acquired pneumonia and otitis media are caused by several bacterial species, including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. For the treatment of these diseases, various quinolones are frequently used. We determined the mutant prevention concentration (MPC) of four quinolones, levofloxacin, sitafloxacin, tosufloxacin, and garenoxacin, using 92 clinical isolates and evaluated each mutant selection window (MSW). Furthermore, the DNA sequence of the quinolone resistance-determining region (QRDR) for the resistant mutant selected based on the MSW was determined. The MIC90 and MPC90 of levofloxacin were 0.781 µg/mL and 6.250 µg/mL for S. pneumoniae and 0.049 µg/mL and 1.563 µg/mL for M. catarrhalis and were higher than those for the other three quinolones. In addition, 5 strains of 30 S. pneumoniae (16.7%) selected based on the MSW of levofloxacin acquired resistance to only levofloxacin. In these 5 strains, a mutation of gyrA and/or parC was detected. In this study, no resistant mutant was selected in the MSW of any of the other three quinolones. On the other hand, clinical isolates of H. influenzae showed no resistance by all quinolone exposure. Finally, The MIC value and the mutation status in the QRDR did not change after 14 passages in antibiotic-free medium. In conclusion, our findings suggest that the increased use of levofloxacin may contribute to the increased quinolone-resistance of S. pneumoniae and M. catarrhalis.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Haemophilus influenzae/efeitos dos fármacos , Moraxella catarrhalis/efeitos dos fármacos , Otite Média/microbiologia , Pneumonia Bacteriana/microbiologia , Quinolonas/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/uso terapêutico , DNA Girase/genética , Análise Mutacional de DNA , DNA Topoisomerase IV/genética , Haemophilus influenzae/genética , Haemophilus influenzae/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/genética , Moraxella catarrhalis/isolamento & purificação , Otite Média/tratamento farmacológico , Pneumonia Bacteriana/tratamento farmacológico , Quinolonas/uso terapêutico , Seleção Genética , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
20.
J Assist Reprod Genet ; 35(11): 2037-2048, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30173352

RESUMO

PURPOSE: A device for closed vitrification was designed to reduce the risk of contamination and investigated on its efficacy for ovarian function recovery after cryopreservation and heterotopic transplantation. METHODS: Ovarian tissues from green fluorescence protein transgenic mice (10 GFP mice) were vitrified using the device, and warmed ovarian tissues were transplanted into the ovarian bursa region in wild-type female mice (6 mice). Fresh ovarian tissues were similarly transplanted as a control. After recovery of the estrous cycle, mice were mated with male mice. Ovarian tissues from six cynomolgus monkeys were vitrified and warmed with the device for autologous, heterotopic transplantation. Fresh tissue transplantation was not performed for the control. Ovarian function was examined by recovery of the hormonal cycle. Histological examination was conducted. RESULTS: The number of live pups per recipient mouse was not significantly different after transplantation of fresh or vitrified-warmed ovarian tissue, although the pregnancy rate was reduced with vitrified tissues. The hormonal cycle was restored in 5/6 monkeys after heterotopic transplantation of vitrified-warmed ovarian tissue. Follicles were harvested at eight sites in the omentum and 13 sites in the mesosalpinx. In vitro maturation (IVM)/IVF produced embryo but did not develop. CONCLUSIONS: Resumption of the hormonal cycles, follicle development, and oocyte retrieval from vitrified-warmed ovarian tissue transplants may indicate that the use of vitrification for ovarian tissue in a closed system has a potential of clinical application without the risk of contaminations. More detailed analyses of the effects of vitrification on ovarian tissue, such as gene expression patterns in oocytes and granulosa cells, may be needed for establishing a standard procedure for cryopreservation of ovarian tissues in human.


Assuntos
Criopreservação , Fertilidade , Recuperação de Oócitos , Oócitos/fisiologia , Transplante Heterotópico , Vitrificação , Animais , Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Macaca fascicularis , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/citologia , Gravidez , Taxa de Gravidez , Reprodução
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