排序方式: 共有42条查询结果,搜索用时 93 毫秒
21.
Norberto Garcia‐Cairasco Miguel Moyses‐Neto Flavio DelVecchio Jos A. C. Oliveira Francisco L. dosSantos Olagide W. Castro Gabriel M. Arisi Mrcio Dantas Ruither O. G. Carolino Joaquim Coutinho‐Netto Andre L. A. Dagostin Marcelo C. A. Rodrigues Ricardo M. Leo Samir A. P. Quintiliano Luiz F. Silva Leonardo Gobbo‐Neto Norberto P. Lopes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(49):12981-12981
22.
The stromal microenvironment is pivotal to prostate physiology and malign transformation. Diabetes leads to testosterone withdrawal and affects the prostate stromal compartment and smooth muscle cells in a similar way to that observed after castration. However the response of these cells and their involvement in extracellular matrix remodeling is not satisfactorily understood. We investigated the changes caused in the short term (one week) by alloxan-induced diabetes in the stromal components of the rat ventral prostate (VP) with an emphasis on morphological alterations of stromal cells, their conversion to a myofibroblast phenotype and the remodeling of extracellular matrix and the influence of insulin therapy. Adult male Wistar rats were assigned into untreated diabetic (n=12), insulin-treated (n=8) diabetic and control (n=10) groups. Diabetes was induced by means of the injection of alloxan (40 mg/kg b.w.), while the control animals received saline solution only. Insulin (5 UI) was administered daily for one week after diabetes diagnosis. Testosterone and estrogen plasma levels were determined. VP was analyzed using transmission electron microscopy. The main stromal cells were identified by means of light microscopy, using immunocytochemistry for specific markers - vimentin for fibroblasts, α-actin for smooth muscle cells (smc) and vimentin/calponin for myofibroblasts, following the estimation of their relative frequency and absolute volume by means of stereology. After one week diabetes led to a marked decrease in testosterone levels and an atrophy of about 35% in the VP. The relative frequency of smc and collagen fibers increased in the VP of diabetic rats but their absolute weight remained unchanged. Experimental diabetes promptly altered smc morphology which assumed at the ultrastructural level a shrunken appearance with the approximation of cytoplasmic dense bodies and also exhibited a decreased immunoreactivity to calponin. The conversion of stromal cells to a myofibroblast phenotype did not occur in alloxan-induced diabetes, as evaluated by double immunoreaction to calponin and vimentin. Insulin treatment maintained testosterone levels and preserved at least partly the cell morphology and collagen fiber organization of the prostate stroma in short-term diabetes. The apparent collagen increase observed by means of microscopic analysis in the stromal prostate compartment in the short term after diabetes is mainly associated with gland atrophy and does not involve the formation of new collagen fibers, the generation of myofibroblast-like cells or the acquisition of a secretory phenotype by stromal cells. 相似文献
23.
Dr. Maria Giulia Dal Farra Dr. Sabine Richert Caterina Martin Charles Larminie Prof. Marina Gobbo Prof. Elisabetta Bergantino Prof. Christiane R. Timmel Dr. Alice M. Bowen Prof. Marilena Di Valentin 《Chemphyschem》2019,20(7):931-935
Light-induced pulsed EPR dipolar spectroscopic methods allow the determination of nanometer distances between paramagnetic sites. Here we employ orthogonal spin labels, a chromophore triplet state and a stable radical, to carry out distance measurements in singly nitroxide-labeled human neuroglobin. We demonstrate that Zn-substitution of neuroglobin, to populate the Zn(II) protoporphyrin IX triplet state, makes it possible to perform light-induced pulsed dipolar experiments on hemeproteins, extending the use of light-induced dipolar spectroscopy to this large class of metalloproteins. The versatility of the method is ensured by the employment of different techniques: relaxation-induced dipolar modulation enhancement (RIDME) is applied for the first time to the photoexcited triplet state. In addition, an alternative pulse scheme for laser-induced magnetic dipole (LaserIMD) spectroscopy, based on the refocused-echo detection sequence, is proposed for accurate zero-time determination and reliable distance analysis. 相似文献
24.
Cover Picture: Light‐Induced Porphyrin‐Based Spectroscopic Ruler for Nanometer Distance Measurements (Chem. Eur. J. 48/2016) 下载免费PDF全文
25.
Matias CN Silva AM Santos DA Gobbo LA Schoeller DA Sardinha LB 《Biomedical chromatography : BMC》2012,26(11):1348-1352
Extracellular water (ECW) assessment is based on dilution techniques, commonly using blood sampling. However, plasma collection is an invasive procedure. We aimed to validate the use of saliva for ECW estimation by the bromide dilution technique using plasma as the reference method, in a sample of elite athletes. A total of 89 elite athletes with a mean age of 20.4 ± 4.4 years were evaluated. Baseline samples were collected before sodium bromide oral dose administration, and enriched samples were collected 3 h post‐dose administration. The bromide concentration was assessed by high‐performance liquid chromatography. Comparison of means, concordance coefficient correlation (CCC), multiple regression and Bland–Altman analysis were performed. The ECW from saliva explained 91% of the variance in ECW by plasma with a standard error of estimation of 0.91 kg. The CCC between alternative and reference methods was 0.952. No significant trend was observed between the mean and difference of the methods, with limits of agreement ranging between ?1.5 and 2.1 kg. These findings reveal that bromide dilution volume calculated from saliva samples is a valid noninvasive method for ECW assessment in elite athletes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
26.
Prof. Dr. Norberto Garcia‐Cairasco Prof. Dr. Miguel Moyses‐Neto Flavio Del Vecchio José A. C. Oliveira Francisco L. dos Santos Dr. Olagide W. Castro Dr. Gabriel M. Arisi Prof. Dr. Márcio Dantas Dr. Ruither O. G. Carolino Prof. Dr. Joaquim Coutinho‐Netto Dr. Andre L. A. Dagostin Dr. Marcelo C. A. Rodrigues Prof. Dr. Ricardo M. Leão Dr. Samir A. P. Quintiliano Prof. Dr. Luiz F. Silva Jr. Prof. Dr. Leonardo Gobbo‐Neto Prof. Dr. Norberto P. Lopes 《Angewandte Chemie (International ed. in English)》2013,52(49):12747-12747
27.
Prof. Marilena Di Valentin Dr. Marco Albertini Maria Giulia Dal Farra Enrico Zurlo Prof. Laura Orian Prof. Antonino Polimeno Prof. Marina Gobbo Prof. Donatella Carbonera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17204-17214
We present a novel pulsed electron paramagnetic resonance (EPR) spectroscopic ruler to test the performance of a recently developed spin‐labeling method based on the photoexcited triplet state (S=1). Four‐pulse electron double resonance (PELDOR) experiments are carried out on a series of helical peptides, labeled at the N‐terminal end with the porphyrin moiety, which can be excited to the triplet state, and with the nitroxide at various sequence positions, spanning distances in the range 1.8–8 nm. The PELDOR traces provide accurate distance measurements for all the ruler series, showing deep envelope modulations at frequencies varying in a progressive way according to the increasing distance between the spin labels. The upper limit is evaluated and found to be around 8 nm. The PELDOR‐derived distances are in excellent agreement with theoretical predictions. We demonstrate that high sensitivity is acquired using the triplet state as a spin label by comparison with Cu(II)–porphyrin analogues. The new labeling approach has a high potential for measuring nanometer distances in more complex biological systems due to the properties of the porphyrin triplet state. 相似文献
28.
Li M Gobbo C De Cat I Eelkema R Vanaverbeke B Lazzaroni R De Feyter S van Esch J 《Langmuir : the ACS journal of surfaces and colloids》2011,27(22):13598-13605
Molecular patterning has received a lot of attention in the past decade; however, the functionalization of these surface-confined 2D patterns on the nanoscale level remains a challenge. Assembling 2D patterns from oligomeric foldamers turns out to be an interesting approach to accomplishing the controlled positioning of functional elements. We designed a family of peptidomimetic foldamers bearing a 2D turn element folding at the liquid/solid interface. The turning element was developed while studying derivatives with one turning unit. Furthermore, folding was found to be induced by the confinement of the surface. This achievement paves the way for the design of foldamers with multiple turns, providing a higher versatility in the functionalization of nanopatterns. 相似文献
29.
The structural and electronic transport properties of La1−x
Ce
x
MnO3 (x=0.0–1.0) have been studied. All the samples exhibit orthorhombic crystal symmetry and the unit cell volume decreases with
Ce doping. They also make a metal-insulator transition (MIT) and transition temperature increases with increase in Ce concentration
up to 50% doping. The system La0.5Ce0.5MnO3 also exhibits MIT instead of charge-ordered state as observed in the hole doped systems of the same composition. 相似文献
30.
S. Masala S. Del Gobbo C. Borriello V. Bizzarro V. La Ferrara M. Re E. Pesce C. Minarini M. De Crescenzi T. Di Luccio 《Journal of nanoparticle research》2011,13(12):6537-6544
The integration of semiconductor nanoparticles (NPs) into a polymeric matrix has the potential to enhance the performance
of polymer-based solar cells taking advantage of the physical properties of NPs and polymers. We synthesize a new class of
CdS-NPs-based active layer employing a low-cost and low temperature route compatible with large-scale device manufacturing.
Our approach is based on the controlled in situ thermal decomposition of a cadmium thiolate precursor in poly(3-hexylthiophene)
(P3HT). The casted P3HT:precursor solid foils were heated up from 200 to 300 °C to allow the precursor decomposition and the
CdS-NP formation within the polymer matrix. The CdS-NP growth was controlled by varying the annealing temperature. The polymer:precursor
weight ratio was also varied to investigate the effects of increasing the NP volume fraction on the solar cell performances.
The optical properties were studied by using UV–Vis absorption and photoluminescence (PL) spectroscopy at room temperature.
To investigate the photocurrent response of P3HT:CdS nanocomposites, ITO/P3HT:CdS/Al solar cell devices were realized. We
measured the external quantum efficiency (EQE) as a function of the wavelength. The photovoltaic response of the devices containing
CdS-NPs showed a variation compared with the devices with P3HT only. By changing the annealing temperature the EQE is enhanced
in the 400–600 nm spectral region. By increasing the NPs volume fraction remarkable changes in the EQE spectra were observed.
The data are discussed also in relation to morphological features of the interfaces studied by Focused Ion Beam technique. 相似文献