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1.
Chest ; 163(4): e163-e166, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37031987

RESUMO

CASE PRESENTATION: A 60-year-old man was referred to a pulmonologist evaluation with persistent dyspnea and cough 1 month after discharge for an acute respiratory failure caused by Legionella pneumophila pneumonia, which required invasive mechanical ventilation. Chest CT scan performed during hospitalization showed lobar consolidation of upper left lobe (Fig 1A). Bronchial culture revealed L pneumophila; the patient was treated with levofloxacin and supported with invasive mechanical ventilation for 2 weeks. Chest radiograph after extubation showed almost complete resolution of infiltrates. After 1 month, the patient still complained of dyspnea and a new chest CT scan was performed: the consolidation migrated (Fig 1B; Video 1).


Assuntos
Legionella pneumophila , Doença dos Legionários , Ventilação não Invasiva , Masculino , Humanos , Pessoa de Meia-Idade , Pulmão , Dispneia
2.
Pulmonology ; 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35190300

RESUMO

BACKGROUND AND OBJECTIVES: Diagnosis of tuberculous pleurisy (TP) may be challenging and it often requires pleural biopsy. A tool able to increase pre-test probability of TP may be helpful to guide diagnostic work-up and enlargement of internal mammary lymph node (IMLN) has been suggested to play a potential role. The aim of the present investigation was to assess role of IMLN involvement in TP in a multi-centric case-control study, by comparing its prevalence and test performance to those observed in patients with infectious, non-tuberculous pleurisy (NTIP), and in controls free from respiratory diseases (CP). METHODS: A total of 419 patients, from 14 Pulmonology Units across Italy were enrolled (127 patients affected by TP, 163 affected by NTIP and 129 CP). Prevalence, accuracy and predictive values of ipsilateral IMLN involvement between cases and control groups were assessed, as well as concordance between chest computed tomography (CT scan) and thoracic ultrasound (TUS) measurements. RESULTS: The prevalence of ipsilateral IMLN involvement in TP was significantly higher than that observed in NTIP and CP groups (respectively 77.2%, 39.3% and 14.7%). Results on test performance, stratified by age, revealed a high positive predictive value in patients aged ≤50 years, while a high negative predictive value in patients aged >50 years. The comparison between CT scan and ultrasound showed moderate agreement (Kappa=0.502). CONCLUSIONS: Evaluation of IMLN involvement plays a relevant role in assessing the pre-test probability of TP. Considering the increasing global prevalence of mycobacterial infections, a tool able to guide diagnostic work-up of suspected TP is crucial, especially where local sources are limited.

3.
J Chem Phys ; 152(20): 204904, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32486676

RESUMO

Combining elastic incoherent neutron scattering and differential scanning calorimetry, we investigate the occurrence of the volume phase transition (VPT) in very concentrated poly-(N-isopropyl-acrylamide) (PNIPAM) microgel suspensions, from a polymer weight fraction of 30 wt. % up to dry conditions. Although samples are arrested at the macroscopic scale, atomic degrees of freedom are equilibrated and can be probed in a reproducible way. A clear signature of the VPT is present as a sharp drop in the mean square displacement of PNIPAM hydrogen atoms obtained by neutron scattering. As a function of concentration, the VPT gets smoother as dry conditions are approached, whereas the VPT temperature shows a minimum at about 43 wt. %. This behavior is qualitatively confirmed by calorimetry measurements. Molecular dynamics simulations are employed to complement experimental results and gain further insights into the nature of the VPT, confirming that it involves the formation of an attractive gel state between the microgels. Overall, these results provide evidence that the VPT in PNIPAM-based systems can be detected at different time- and length-scales as well as under overcrowded conditions.

4.
Nanotechnology ; 31(27): 275709, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32208377

RESUMO

The strongly correlated rare earth nitrides display unusual coupled magnetic, electronic and superconducting properties, with predicted topological states. However, their air-sensitiveness has prevented in-depth investigations of their properties. In this paper, we show that a 100 nm thick epitaxial samarium layer provides adequate passivation of 100 nm thick thin films of gadolinium nitride (GdN), the prototypical rare earth nitride, enabling ex-situ magnetic and structural characterizations. Using reflection high-energy electron diffraction, atomic force microscopy and energy dispersive x-ray spectroscopy, we investigate the thermal desorption of the samarium layer under vacuum. We finally demonstrate successful removal of the samarium capping layer in a separate vacuum chamber after exposure to air using a combination of argon ion sputtering and thermal desorption at 400 °C, recovering the GdN surface.

5.
Sci Rep ; 10(1): 3298, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094390

RESUMO

Halophilic proteins subjected to below about 15% salt in vitro denature through misfolding, aggregation and/or precipitation. Halobacteria, however, have been detected in environments of fluctuating salinity such as coastal salterns and even around fresh water springs in the depths of the Dead Sea. In order to identify the underlying mechanisms of low salt survival, we explored the reactivation capacity of Halobacterium (Hbt) salinarum sub-populations after incubation in low salt media and recovery in physiological salt. Respiratory oxygen consumption was assessed in stressed cells and cell viability was estimated by Live/Dead staining and flow cytometry. In vivo neutron scattering experiments showed that the recovery of Hbt salinarum sub-populations exposed to severe low salt conditions is related to a rapid retrieval of functional molecular dynamics in the proteome. In the hypothesis that the observations on Hbt salinarum have wider relevance, they could be of key ecological significance for the dispersion of extremophiles when environmental fluctuations become severe.


Assuntos
Halobacterium salinarum/fisiologia , Estresse Salino , Sais/química , Archaea , Ecologia , Citometria de Fluxo , Água Doce , Oxigênio/fisiologia , Desnaturação Proteica , Dobramento de Proteína , Proteoma , Espalhamento de Radiação , Cloreto de Sódio/química
6.
Sci Rep ; 9(1): 14694, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604980

RESUMO

Combined neutron scattering and diffusion nuclear magnetic resonance experiments have been used to reveal significant interregional asymmetries (lateralization) in bovine brain hemispheres in terms of myelin arrangement and water dynamics at micron to atomic scales. Thicker myelin sheaths were found in the left hemisphere using neutron diffraction. 4.7 T dMRI and quasi-elastic neutron experiments highlighted significant differences in the properties of water dynamics in the two hemispheres. The results were interpreted in terms of hemisphere-dependent cellular composition (number of neurons, cell distribution, etc.) as well as specificity of neurological functions (such as preferential networking).


Assuntos
Cerebelo/diagnóstico por imagem , Cérebro/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Dominância Cerebral , Difusão Facilitada/fisiologia , Difração de Nêutrons/métodos , Espalhamento a Baixo Ângulo , Água/química , Animais , Bovinos , Bainha de Mielina/ultraestrutura
7.
J R Soc Interface ; 16(157): 20190186, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31409238

RESUMO

Water diffusion is an optimal tool for investigating the architecture of brain tissue on which modern medical diagnostic imaging techniques rely. However, intrinsic tissue heterogeneity causes systematic deviations from pure free-water diffusion behaviour. To date, numerous theoretical and empirical approaches have been proposed to explain the non-Gaussian profile of this process. The aim of this work is to shed light on the physics piloting water diffusion in brain tissue at the micrometre-to-atomic scale. Combined diffusion magnetic resonance imaging and first pioneering neutron scattering experiments on bovine brain tissue have been performed in order to probe diffusion distances up to macromolecular separation. The coexistence of free-like and confined water populations in brain tissue extracted from a bovine right hemisphere has been revealed at the micrometre and atomic scale. The results are relevant for improving the modelling of the physics driving intra- and extracellular water diffusion in brain, with evident benefit for the diffusion magnetic resonance imaging technique, nowadays widely used to diagnose, at the micrometre scale, brain diseases such as ischemia and tumours.


Assuntos
Encéfalo/fisiologia , Bovinos/fisiologia , Imageamento por Ressonância Magnética , Difração de Nêutrons , Água/metabolismo , Animais
8.
J Chem Phys ; 141(20): 205101, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25429962

RESUMO

Myelin is an insulating, multi-lamellar membrane structure wrapped around selected nerve axons. Increasing the speed of nerve impulses, it is crucial for the proper functioning of the vertebrate nervous system. Human neurodegenerative diseases, such as multiple sclerosis, are linked to damage to the myelin sheath through demyelination. Myelin exhibits a well defined subset of myelin-specific proteins, whose influence on membrane dynamics, i.e., myelin flexibility and stability, has not yet been explored in detail. In a first paper [W. Knoll, J. Peters, P. Kursula, Y. Gerelli, J. Ollivier, B. Demé, M. Telling, E. Kemner, and F. Natali, Soft Matter 10, 519 (2014)] we were able to spotlight, through neutron scattering experiments, the role of peripheral nervous system myelin proteins on membrane stability at room temperature. In particular, the myelin basic protein and peripheral myelin protein 2 were found to synergistically influence the membrane structure while keeping almost unchanged the membrane mobility. Further insight is provided by this work, in which we particularly address the investigation of the membrane flexibility in the low temperature regime. We evidence a different behavior suggesting that the proton dynamics is reduced by the addition of the myelin basic protein accompanied by negligible membrane structural changes. Moreover, we address the importance of correct sample preparation and characterization for the success of the experiment and for the reliability of the obtained results.


Assuntos
Temperatura Baixa , Membranas/química , Modelos Biológicos , Proteínas da Mielina/metabolismo , Humanos , Membranas/fisiologia , Proteínas da Mielina/química , Reprodutibilidade dos Testes
9.
J Phys Chem B ; 118(11): 2913-23, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24568616

RESUMO

Proteins and polypeptides are characterized by low-frequency vibrations in the terahertz regime responsible for the so-called "boson peak". The shape and position of this peak are related to the mechanical properties of peptide chains. Amyloid fibrils are ordered macromolecular assemblies, spontaneously formed in nature, characterized by unique biological and nanomechanical properties. In this work, we investigate the effects of the amyloid state and its polymorphism on the boson peak. We used inelastic neutron scattering to probe low-frequency vibrations of the glucagon polypeptide in the native state and in two different amyloid morphologies in both dry and hydrated sample states. The data show that amyloid fibril formation and hydration state affect the softness of the polypeptide not only by changing the distribution of vibrational modes but also, and most significantly, the dissipative mechanisms of collective low-frequency vibrations provided by water-protein and protein-protein interactions. We show how the morphology of the fibril is able to tune these effects. Atomic fluctuations were also measured by elastic neutron scattering. The data confirm that any effect of protein aggregation on fluctuation amplitudes is essentially due to changes in surface exposure to hydration water. The results demonstrate the importance of protein-protein and protein-water interactions in the dynamics and mechanics of amyloid fibrils.


Assuntos
Amiloide/química , Difração de Nêutrons , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
10.
Andrologia ; 46(9): 1067-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24215716

RESUMO

The efficacy of recombinant human follicle-stimulating hormone (rhFSH) in the treatment of normogonadotropic patients with male-factor infertility was assessed. Forty-five infertile men with moderate/severe oligoasthenozoospermia and normal FSH, luteinizing hormone (LH) and testosterone (T) levels were treated with high rhFSH dose (300 IU) on alternate days for ≥4 months. In all, the seminal parameters, endocrine profile (FSH, LH, prolactin (PRL), total and free T and estradiol) and pregnancy rate were evaluated before, during and after rhFSH treatment. Fifteen infertile men were treated with placebo and studied in the same way, as control group. rhFSH treatment induced a marked increase in sperm count and no change in sperm motility, morphology and viability. No changes in seminal parameters were observed in the placebo group. FSH levels increased during treatment with rhFSH and not with placebo. No variations in LH, PRL, free and total T and estradiol were evidenced during treatment. A significant pregnancy rate in rhFSH versus placebo patients was also highlighted. Prolonged treatment with high rhFSH doses leads to increase sperm count and improve the spontaneous pregnancy rate in normogonadotropic infertile patients with oligoasthenozoospermia. rhFSH may represent a rational and useful tool in the treatment of male-factor infertility.


Assuntos
Hormônio Foliculoestimulante Humano/administração & dosagem , Infertilidade Masculina/tratamento farmacológico , Astenozoospermia/sangue , Astenozoospermia/tratamento farmacológico , Astenozoospermia/patologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante Humano/sangue , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/patologia , Hormônio Luteinizante/sangue , Masculino , Oligospermia/sangue , Oligospermia/tratamento farmacológico , Oligospermia/patologia , Gravidez , Prolactina/sangue , Proteínas Recombinantes/administração & dosagem , Contagem de Espermatozoides , Testosterona/sangue
11.
Phys Rev Lett ; 111(16): 167206, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24182299

RESUMO

Europium nitride is semiconducting and contains nonmagnetic Eu3+, but substoichiometric EuN has Eu in a mix of 2+ and 3+ charge states. We show that at Eu2+ concentrations near 15%-20% EuN is ferromagnetic with a Curie temperature as high as 120 K. The Eu3+ polarization follows that of the Eu2+, confirming that the ferromagnetism is intrinsic to the EuN which is, thus, a novel diluted magnetic semiconductor. Transport measurements shed light on the likely exchange mechanisms.

12.
J Hazard Mater ; 241-242: 146-53, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23040660

RESUMO

Spirulina platensis microalgae (SP) and commercial activated carbon (AC) were compared as adsorbents to remove Reactive Red 120 (RR-120) textile dye from aqueous effluents. The batch adsorption system was evaluated in relation to the initial pH, contact time, initial dye concentration and temperature. An alternative kinetic model (general order kinetic model) was compared with the traditional pseudo-first order and pseudo-second order kinetic models. The equilibrium data were fitted to the Langmuir, Freundlich and Liu isotherm models, and the thermodynamic parameters were also estimated. Finally, the adsorbents were employed to treat a simulated dye-house effluent. The general order kinetic model was more appropriate to explain RR-120 adsorption by SP and AC. The equilibrium data were best fitted to the Liu isotherm model. The maximum adsorption capacities of RR-120 dye were found at pH 2 and 298 K, and the values were 482.2 and 267.2 mg g(-1) for the SP and AC adsorbents, respectively. The thermodynamic study showed that the adsorption was exothermic, spontaneous and favourable. The SP and AC adsorbents presented good performance for the treatment of simulated industrial textile effluents, removing 94.4-99.0% and 93.6-97.7%, respectively, of the dye mixtures containing high saline concentrations.


Assuntos
Carvão Vegetal/química , Microalgas/química , Spirulina/química , Triazinas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Modelos Teóricos , Indústria Têxtil , Termodinâmica , Águas Residuárias/química
13.
J R Soc Interface ; 9(76): 2845-55, 2012 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-22696485

RESUMO

Thermodynamic stability, configurational motions and internal forces of haemoglobin (Hb) of three endotherms (platypus, Ornithorhynchus anatinus; domestic chicken, Gallus gallus domesticus and human, Homo sapiens) and an ectotherm (salt water crocodile, Crocodylus porosus) were investigated using circular dichroism, incoherent elastic neutron scattering and coarse-grained Brownian dynamics simulations. The experimental results from Hb solutions revealed a direct correlation between protein resilience, melting temperature and average body temperature of the different species on the 0.1 ns time scale. Molecular forces appeared to be adapted to permit conformational fluctuations with a root mean square displacement close to 1.2 Å at the corresponding average body temperature of the endotherms. Strong forces within crocodile Hb maintain the amplitudes of motion within a narrow limit over the entire temperature range in which the animal lives. In fully hydrated powder samples of human and chicken, Hb mean square displacements and effective force constants on the 1 ns time scale showed no differences over the whole temperature range from 10 to 300 K, in contrast to the solution case. A complementary result of the study, therefore, is that one hydration layer is not sufficient to activate all conformational fluctuations of Hb in the pico- to nanosecond time scale which might be relevant for biological function. Coarse-grained Brownian dynamics simulations permitted to explore residue-specific effects. They indicated that temperature sensing of human and chicken Hb occurs mainly at residues lining internal cavities in the ß-subunits.


Assuntos
Adaptação Biológica/fisiologia , Jacarés e Crocodilos/fisiologia , Galinhas/fisiologia , Hemoglobinas/química , Ornitorrinco/fisiologia , Conformação Proteica , Temperatura , Sequência de Aminoácidos , Animais , Temperatura Corporal , Dicroísmo Circular , Biologia Computacional , Simulação por Computador , Humanos , Dados de Sequência Molecular , Difração de Nêutrons , Alinhamento de Sequência , Especificidade da Espécie , Termodinâmica
14.
J Environ Manage ; 92(4): 1237-47, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21195535

RESUMO

The cupuassu shell (Theobroma grandiflorum) which is a food residue was used in its natural form as biosorbent for the removal of C.I. Reactive Red 194 and C.I. Direct Blue 53 dyes from aqueous solutions. This biosorbent was characterized by infrared spectroscopy, scanning electron microscopy, and nitrogen adsorption/desorption curves. The effects of pH, biosorbent dosage and shaking time on biosorption capacities were studied. In acidic pH region (pH 2.0) the biosorption of the dyes were favorable. The contact time required to obtain the equilibrium was 8 and 18 h at 298 K, for Reactive Red 194 and Direct Blue 53, respectively. The Avrami fractionary-order kinetic model provided the best fit to experimental data compared with pseudo-first-order, pseudo-second-order and chemisorption kinetic adsorption models. The equilibrium data were fitted to Langmuir, Freundlich, Sips and Radke-Prausnitz isotherm models. For both dyes the equilibrium data were best fitted to the Sips isotherm model.


Assuntos
Corantes/metabolismo , Malvaceae/metabolismo , Adsorção , Brasil , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Modelos Químicos , Dinâmica não Linear , Têxteis
15.
J Hazard Mater ; 181(1-3): 366-74, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20554108

RESUMO

The octosilicate Na-RUB-18 has the ability to exchange its original sodium with cetyltrimethylammonium cations. This procedure leads to interlayer space expansion, with the aim of obtaining inorganic-organic nanostructured hybrids by chemical modification reactions. The silylating agent 3-trimethoxysilylpropylurea was attached to the inorganic layer using heterogeneous methodology. The new organofunctionalized material was characterized by elemental analysis, X-ray diffraction, (13)C and (29)Si nuclear magnetic resonances in the solid state, infrared spectroscopy, thermogravimetry and scanning electron microscopy. The amount of silylating agent immobilized on surface was 2.03 mmol g(-1), with a basal distance of 2.43 nm. Nuclear magnetic resonance of (13)C and (29)Si nuclei evidenced covalent bond formation between organosilyl and silanol groups at the surface. The new synthesized nanostructured layered material was able to remove the textile dye Reactive Black 5 from aqueous solution, followed through a batchwise process. The effects of stirring time, adsorbent dosage and pH on the adsorption capacity demonstrated that 150 min is enough to reach equilibrium at 298+/-1 K at pH 3.0. Based on error function values the data were best fitted to fractional-order kinetic models and compared to pseudo-first-order, pseudo-second-order and chemisorption kinetic models. The equilibrium data were better fitted to the Sips isotherm models.


Assuntos
Corantes/isolamento & purificação , Resíduos Industriais/prevenção & controle , Silicatos/química , Têxteis , Cinética , Propriedades de Superfície
16.
J Environ Manage ; 91(8): 1695-706, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20398999

RESUMO

Activated (AC-PW) and non-activated (C-PW) carbonaceous materials were prepared from the Brazilian-pine fruit shell (Araucaria angustifolia) and tested as adsorbents for the removal of reactive orange 16 dye (RO-16) from aqueous effluents. The effects of shaking time, adsorbent dosage and pH on the adsorption capacity were studied. RO-16 uptake was favorable at pH values ranging from 2.0 to 3.0 and from 2.0 to 7.0 for C-PW and AC-PW, respectively. The contact time required to obtain the equilibrium using C-PW and AC-PW as adsorbents was 5 and 4h at 298 K, respectively. The fractionary-order kinetic model provided the best fit to experimental data compared with other models. Equilibrium data were better fit to the Sips isotherm model using C-PW and AC-PW as adsorbents. The enthalpy and entropy of adsorption of RO-16 were obtained from adsorption experiments ranging from 298 to 323 K.


Assuntos
Compostos Azo/isolamento & purificação , Carbono/farmacocinética , Corantes/isolamento & purificação , Pinus , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Brasil , Cinética , Microscopia Eletrônica de Varredura , Modelos Estatísticos , Nozes , Termodinâmica
17.
Rev Pneumol Clin ; 66(2): 145-53, 2010 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20413050

RESUMO

The aim of this article is to suggest a practical approach when faced with an excavated lesion in a chest X-ray. This is a classic situation both in general practice and in emergency units. A rigorous diagnostic approach is necessary after eliminating the main differential diagnosis. The main diagnoses consist of lung cancer, tuberculosis and abscess. Bronchial endoscopy is essential, but can be misleading. The diagnosis of an excavated pulmonary lesion is not always easy. It must be established rapidly and treated as soon as possible.


Assuntos
Pneumopatias/diagnóstico , Abscesso/diagnóstico , Árvores de Decisões , Diagnóstico Diferencial , Humanos , Pneumopatias/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Radiografia , Tuberculose Pulmonar/diagnóstico
18.
Vet J ; 185(3): 344-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19647456

RESUMO

Six 20-24-month-old heifers received ketamine (KE), 2% lidocaine (Li), or ketamine and 2% lidocaine (KELI) into the first intercoccygeal (Co(1)-Co(2)) epidural space while standing. Heart rate, arterial blood pressure (systolic, diastolic, and mean), respiratory rate, rectal temperature, analgesia, sedation, and ataxia were determined before treatment and at predetermined intervals. Subjective scoring was used to assess pain and discomfort in reproductive manipulations. The duration of analgesia was 35+/-14 min for Li, 48+/-11 min for KE, and 35+/-7 min for KELI (P>0.05). Motor block determined by KE, Li, or KELI treatments was restricted to tail, external genital organs (vulva and vagina), anus, and rectum, with little interference in the cervix or uterus. It was concluded that epidural ketamine, 2% lidocaine, or their combination produced satisfactory analgesia without discomfort or ataxia and facilitated reproductive manipulations.


Assuntos
Analgesia Epidural/veterinária , Ketamina/farmacologia , Lidocaína/farmacologia , Técnicas Reprodutivas/veterinária , Animais , Pressão Sanguínea/efeitos dos fármacos , Bovinos , Combinação de Medicamentos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Medição da Dor/veterinária , Respiração/efeitos dos fármacos
19.
J Colloid Interface Sci ; 336(2): 398-405, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19447406

RESUMO

Crystalline layered sodium kenyaite was exchanged to proton kenyaite when reacted with hydrochloric acid solution, providing a new surface with available silanol groups that are able to couple with N-3-trimethoxysilylpropylethylenediamine silylating agent, after prior expansion of the basal distance with the polar organic solvent dimethyl sulfoxide. The resulting organofunctionalized nanomaterial (2N-Ken) was characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, carbon and silicon nuclear magnetic resonances in the solid state, surface analysis, porosity, thermogravimetry, and electron scanning microscopy. The quantity of silylating agent incorporated into the nanospace, calculated from the nitrogen elemental analysis, was determined as 0.48 mmol g(-1), after expanding of the acidic precursor basal distance from 1.62 to 1.99 nm. The presence of a covalent silicon-carbon bond of the organosilyl moiety on the inorganic layered structure was confirmed through nuclear magnetic resonance. This new nanomaterial has the ability to extract the Sumifix Brilliant Orange 3R textile dye from aqueous solution, using a batchwise process. The effects of stirring time, adsorbent dosage, and pH on the adsorption capacity demonstrated that 4 h is enough to reach equilibrium at 298+/-1 K under pH 4.0. Based on error function values (F(error)) the data were best fitted to fractional-order and chemisorption kinetic models when compared to pseudo-first-order and pseudo-second-order kinetic models. The equilibrium data were better fitted to the Sips isotherm model.

20.
Rev Mal Respir ; 26(3): 315-8, 2009 Mar.
Artigo em Francês | MEDLINE | ID: mdl-19367205

RESUMO

INTRODUCTION: The identification of a ground-glass opacity on chest CT is a frequent problem because of the number of exams performed. OBSERVATION: We report the case of a man of 66 years with a very slowly increasing ground-glass opacity during 5 years. Although the lesion was negative for positron emission tomography and because of its increasing size and the appearance of a solid part, our patient underwent surgery. The final diagnosis was stage I adenocarcinoma. CONCLUSIONS: The management of a ground glass opacity differs from solid nodules of the lung. The rate of malignancy is high in the published studies, especially in south-east Asia. PET is not as useful as for solid nodules. Long term follow up is necessary because of the long doubling time in these neoplasms.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Idoso , Progressão da Doença , Humanos , Masculino , Tomografia Computadorizada por Raios X
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