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1.
Vascul Pharmacol ; 141: 106930, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34728386

RESUMO

Little is known on the cerebrovascular BDNF (brain-derived neurotrophic factor)/TrkB (tropomyosin related kinase B) pathway. This study investigated the contribution of endogenous endothelial BDNF to the control of vascular tone of rat middle cerebral artery (MCA) and the capacity of exogenous agonist of TrkB receptors to induce their relaxation. Endothelial cells constitutively expressed both BDNF and activated TrkB receptors. Supporting endothelial BDNF as an autocrine regulator of basal myogenic tone, incubation of MCA with the TrkB antagonist cyclotraxin B induced contraction as observed with incubation in the presence of inhibitors of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) production. Exposure of MCA with the TrkB agonist LM22A-4 that increased expression of TrkB receptors phosphorylated at tyrosine 816 induced relaxation of preconstricted MCA (EC50 6.7 × 10-8 mol/L) as efficiently than acetylcholine (EC50 5.3 × 10-8 mol/L). Finally, endothelium removal, exposure to a TrkB antagonist or to inhibitors of NO and EDHF production prevented the relaxant effect of LM22A-4. In conclusion, our study identified endothelial BDNF as a new autocrine regulator of vascular tone of MCA, thus making the endothelial BDNF/TrkB pathway an attractive target for strategies aiming to improve blood supply to the brain.


Assuntos
Células Endoteliais , Receptor trkB , Animais , Fatores Biológicos , Células Endoteliais/metabolismo , Endotélio/metabolismo , Artéria Cerebral Média/metabolismo , Ratos , Receptor trkB/metabolismo
2.
J Phys Chem A ; 125(4): 1069-1081, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33472363

RESUMO

The coupling protocols combining photoemission spectroscopy and other characterization methods such as electrochemical, electrical, optical, thermal, or magnetic paved the way to considerable progress in the field of materials science. Access to complementary data on the same object is relevant, but in the vast majority of cases, it is carried out sequentially and separately. This raises the complex question of the equivalence of the analyzed surfaces subjected to these different characterizations. In the frame of lithium ion battery technology (LIB), several techniques have been developed to follow in operando condition the reactivity of electro-active materials toward liquid or solid electrolytes. Besides the knowledge of the redox processes obtained using operando protocols, especially at the interfaces, some limitations associated with material sensitivity and/or the characterization techniques are still a breakdown to widen our understanding of the origin of the LIB performance degradation processes. Herein, we propose a new design of an operando cell adapted to perform X-ray photoemission spectroscopy (XPS) at the interface between electrode and electrolyte under electrochemical solicitations. To illustrate its performance, the crucial issues associated with the lithium metal interface have been scrutinized using Li/Li symmetrical cells and two types of ionic liquids, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (C1C6ImTFSI) and 1-hexyl-3-methylimidazolium bis(fluorosulfonyl)imide (C1C6ImFSI) laden with LiTFSI salt. Our original setup allowed us to follow-up the lithium surface reactivity toward these ionic liquid based electrolytes in open circuit voltage condition and under polarization. Beside the gain of time and the matter saving, we highlighted and optimized the blocking issues to perform accurate OXPS measurement for probing the evolution of the chemical structure and the surface potential change at the interface lithium/electrolyte in dynamic mode.

3.
Infection ; 49(2): 277-285, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33095391

RESUMO

PURPOSE: Invasive candidiasis (IC) is a challenging clinical condition, burdened by relevant mortality and morbidity. There is limited knowledge on the occurrence and management of IC in Internal Medicine Units (IMUs). Aim of this study was to provide real-world data on this topic. METHODS: Consecutive objectively diagnosed cases of IC were collected in this prospective registry, which involved 18 IMUs in Italy. Patients were followed-up to 90 days from the diagnosis of candidemia. RESULTS: A total of 111 patients were observed (median age 78, IQR 67-83) for an overall incidence of infection of 1.89 cases/1000 hospital admissions. Candida albicans was the most frequent isolated species (62%), followed by Candida parapsilosis (17%) and Candida glabrata (13%). Echinocandins and fluconazole were used as initial therapy in 56.8 and 43.2% of patients, respectively. Antifungal therapy was started within 24 h in 18.9% of patients, in 40.6% in the period 1-3 days, and in 40.5% of patients more than 3 days after blood cultures. Death rate was 19.8% at 30 days and 40.5% at 90 days. At multivariable analysis concomitant bacteremia (i.e. polymicrobial sepsis), and fluconazole as the initial therapy were associated with an increased risk of death at 90 days. CONCLUSIONS: The incidence of IC is not negligible, and our registry confirmed that these patients have a relevant mortality rate at 90 days. Concomitant bacteremia, featuring polymicrobial sepsis, and starting antifungal treatment with fluconazole instead of echinocandins independently increase the risk of death. Efforts are needed to improve the awareness and management of IC in IMUs.


Assuntos
Candidíase Invasiva , Sociedades Científicas , Idoso , Antifúngicos/uso terapêutico , Candida , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/epidemiologia , Fluconazol/uso terapêutico , Humanos , Itália/epidemiologia , Sistema de Registros
4.
J Phys Chem B ; 124(35): 7625-7635, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32790393

RESUMO

We reported a new perspective on the correlation between the electronic structure of an ionic liquid (IL)-based electrolyte probed by X-ray photoelectron spectroscopy and the transport properties analyzed by impedance spectroscopy. We highlighted the core level chemical shifts of 1-hexyl-3-methylimidazolium (bis(trifluoromethanesulfonyl)imide) (C1C6ImTFSI), 1-hexyl-3-methylimidazolium bis(fluorosulfonyl)imide (C1C6ImFSI), and 1-hexyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide (C1C1C6ImTFSI) laden with LiTFSI salt and vinylene carbonate (VC) or fluoroethylene carbonate (FEC) with regard to the transport properties of cations and anions. We pointed out based on detailed binding energy shift analyses a clear effect of the anion on the local organization of Li+ ions. The significant peak shift in the case of C1C6ImTFSI laden with LiTFSI corroborates the formation of [Li(TFSI)2]- complexes. On the contrary, the lower amplitude of the binding energy shift of C1C6ImFSI for both anion- and cation-related peaks indicates that the electronic distribution around the cation and the anion is not affected when the LiTFSI salt is added, which plays a strong role in the ion dynamics (lower viscosity) of the electrolyte. The X-ray photoelectron spectroscopy (XPS) result supports the preponderant role of imidazolium ionic liquid based on FSI anion to form an electrolyte less prone to form ionic complexes. The methylation of the imidazolium cation contributes to the reduction of the interaction between the C1C1C6Im cation and TFSI anion, while additives VC and FEC contribute to the change of the alkyl configuration in C1C6Im cation, leading to the modification of the macroscopic properties of the ILs.

5.
ACS Appl Mater Interfaces ; 11(24): 21955-21964, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31124650

RESUMO

Lithium reactivity toward an electrolytic media and dendrite growth phenomenon constitutes the main drawback for its use as an anode material for the lithium battery technology. Ionic liquids (ILs) were pointed out as promising electrolyte solvent candidates to prevent thermal runaway in a lithium battery system. However, the reactivity of lithium toward such a kind of an electrolyte is still under debate. In this study, the interaction between lithium metal and imidazolium-based ILs, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (C1C6ImTFSI) and 1-hexyl-3-methylimidazolium bis(fluorosulfonyl)imide (C1C6ImFSI), has been investigated based on the nondestructive methodology coupling electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) in coin cells aged several days at open-circuit voltage. The main components detected by XPS in the bulk separator and at the surface of the lithium metal are the byproducts of cation and anion degradation. Similarities and differences were noticed depending on the anion nature of bis(trifluoromethylsulfonyl)imide versus bis(fluorosulfonyl)imide. The role of lithium salt addition (LiTFSI) was also pointed, giving rise to the stability improvement of the electrolytic solution toward the lithium anode. A direct correlation between the resistance of the bulk electrolyte and of the interface electrolyte/lithium and chemical composition changes were established based on a detailed EIS and XPS combined study.

6.
Neurotox Res ; 34(1): 93-108, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29344837

RESUMO

[Cu(thp)4]PF6, [Cu(PTA)4]PF6, [Au(thp)4]PF6 and [Au(PTA)4]PF6 are phosphane (thp = tris(hydroxymethyl)phosphane; PTA = 1,3,5-triaza-7-phosphaadamantane) copper(I) and gold(I) water-soluble complexes characterized by high anticancer activity in a wide range of solid tumors, often able to overcome drug resistance of platinum-based compounds. For these reasons, they have been proposed as a valid alternative to platinum-based chemotherapeutic drugs (e.g., cisplatin and oxaliplatin). In vitro experiments performed on organotypic cultures of dorsal root ganglia (DRG) from 15-day-old rat embryos revealed that copper-based compounds were not neurotoxic even at concentrations higher than the IC50 obtained in human cancer cells while [Au(PTA)4]PF6 was neurotoxic at lower concentration than IC50 in cancer cell lines. The ability of these compounds to hinder the proteasome machinery in DRG neurons was tested by fluorimetric assay showing that the non-neurotoxic copper-based complexes do not inhibit proteasome activity in DRG primary neuron cultures. On the contrary, the neurotoxic complex [Au(PTA)4]PF6, induced a significant inhibition of proteasome activity even at concentrations lower than the IC50 in cancer cells. The proteasome inhibition induced by [Au(PTA)4]PF6 was associated with a significant increase in α-tubulin polymerization that was not observed following the treatment with copper-based compounds. Uptake experiments performed by atomic absorption spectrometry showed that both copper-based complexes and [Au(PTA)4]PF6 are internalized in neuron cultures. In vitro and in vivo preliminary data confirmed copper-based complexes as the most promising compounds, not only for their anticancer activity but also concerning the peripheral neurotoxicity profile.


Assuntos
Adamantano/análogos & derivados , Antineoplásicos/farmacologia , Neurônios/efeitos dos fármacos , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Potenciais de Ação/efeitos dos fármacos , Adamantano/química , Adamantano/farmacologia , Animais , Antineoplásicos/química , Bortezomib/farmacologia , Carcinoma/patologia , Linhagem Celular Tumoral , Células Cultivadas , Cisplatino/farmacologia , Cobre/metabolismo , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Feminino , Gânglios Espinais/citologia , Ouro/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Crescimento Neuronal/efeitos da radiação , Nervos Periféricos/efeitos dos fármacos , Nervos Periféricos/fisiologia , Polimerização/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ratos Sprague-Dawley , Tubulina (Proteína)/metabolismo
7.
J Diabetes Metab Disord ; 17(2): 393-399, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30918874

RESUMO

OBJECTIVE: To evaluate the basal/total ratio of daily insulin dose (b/T) in outpatients with diabetes type 1 (DM1) and type 2 (DM2) on basal-bolus regimen, by investigating whether there is a relationship with HbA1c and episodes of hypoglycemia. METHODS: Multicentric, observational, cross-sectional study in Italy. Adult DM1 (n = 476) and DM2 (n = 541) outpatients, with eGFR >30 mL/min/1.73 m2, on a basal-bolus regimen for at least six months, were recruited from 31 Italian Diabetes services between March and September 2016. Clinicaltrials.govID: NCT03489031. RESULTS: Total daily insulin dose was significantly higher in DM2 patients (52.3 ± 22.5 vs. 46 ± 20.9 U/day), but this difference disappeared when insulin doses were normalized for body weight. The b/T ratio was lower than 0.50 in both groups: 0.46 ± 0.14 in DM1 and 0.43 ± 0.15 in DM2 patients (p = 0.0011). The b/T was significantly higher in the patients taking metformin in both groups, and significantly different according to the type of basal insulin (Degludec, 0.48 in DM1 and 0.44 in DM2; Glargine, 0.44 in DM1 and 0.43 in DM2; Detemir, 0.45 in DM1 and 0.39 in DM2). The b/T ratio was not correlated in either group to HbA1c or incidence of hypoglycemia (<40 mg/dL, or requiring caregiver intervention, in the last three months). In the multivariate analysis, metformin use and age were independent predictors of the b/T ratio in both DM1 and DM2 patients, while the type of basal insulin was an independent predictor only in DM1. CONCLUSION: The b/T ratio was independent of glycemic control and incidence of hypoglycemia.

9.
Nanotechnology ; 29(3): 035201, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29235441

RESUMO

Computing with resistive-switching (memristive) memory devices has shown much recent progress and offers an attractive route to circumvent the von-Neumann bottleneck, i.e. the separation of processing and memory, which limits the performance of conventional computer architectures. Due to their good scalability and nanosecond switching speeds, carbon-based resistive-switching memory devices could play an important role in this respect. However, devices based on elemental carbon, such as tetrahedral amorphous carbon or ta-C, typically suffer from a low cycling endurance. A material that has proven to be capable of combining the advantages of elemental carbon-based memories with simple fabrication methods and good endurance performance for binary memory applications is oxygenated amorphous carbon, or a-CO x . Here, we examine the memristive capabilities of nanoscale a-CO x devices, in particular their ability to provide the multilevel and accumulation properties that underpin computing type applications. We show the successful operation of nanoscale a-CO x memory cells for both the storage of multilevel states (here 3-level) and for the provision of an arithmetic accumulator. We implement a base-16, or hexadecimal, accumulator and show how such a device can carry out hexadecimal arithmetic and simultaneously store the computed result in the self-same a-CO x cell, all using fast (sub-10 ns) and low-energy (sub-pJ) input pulses.

10.
Eur J Nutr ; 57(2): 679-688, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28004268

RESUMO

PURPOSE: Proper evaluation of polyphenols intake at the population level is a necessary step in order to establish possible associations with health outcomes. Available data are limited, and so far no study has been performed in people with diabetes. The aim of this work was to document the intake of polyphenols and their major food sources in a cohort of people with type 2 diabetes and in socio-demographic subgroups. METHODS: We studied 2573 men and women aged 50-75 years. Among others, anthropometry was measured by standard protocol and dietary habits were investigated by food frequency questionnaire (EPIC). The intake of polyphenols was evaluated using US Department of Agriculture and Phenol-Explorer databases. RESULTS: The mean total polyphenol intake was 683.3 ± 5.8 mg/day. Non-alcoholic beverages represented the main food source of dietary polyphenols and provided 35.5% of total polyphenol intake, followed by fruits (23.0%), alcoholic beverages (14.0%), vegetables (12.4%), cereal products and tubers (4.6%), legumes (3.7%) and oils (2.1%); chocolate, cakes and nuts are negligible sources of polyphenols in this cohort. The two most important polyphenol classes contributing to the total intake were flavonoids (47.5%) and phenolic acids (47.4%). Polyphenol intake increased with age and education level and decreased with BMI; furthermore, in the northern regions of Italy, the polyphenol intake was slightly, but significantly higher than in the central or southern regions. CONCLUSIONS: The study documents for the first time the intake of polyphenols and their main food sources in people with diabetes using validated and complete databases of the polyphenol content of food. Compared with published data, collected in people without diabetes, these results suggest a lower intake and a different pattern of intake in people with diabetes.


Assuntos
Antioxidantes/administração & dosagem , Diabetes Mellitus Tipo 2/dietoterapia , Dieta para Diabéticos , Dieta Saudável , Flavonoides/administração & dosagem , Cooperação do Paciente , Fenóis/administração & dosagem , Idoso , Antioxidantes/análise , Bebidas/análise , Cinamatos/administração & dosagem , Cinamatos/análise , Estudos de Coortes , Estudos Transversais , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/etnologia , Dieta para Diabéticos/etnologia , Dieta Saudável/etnologia , Feminino , Flavonoides/análise , Frutas/química , Glicosídeos/administração & dosagem , Glicosídeos/análise , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Cooperação do Paciente/etnologia , Fenóis/análise , Polifenóis/administração & dosagem , Polifenóis/análise
11.
Dalton Trans ; 44(48): 21041-52, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26587827

RESUMO

The novel NHC ligand precursor 1,4-bis(4-nitrobenzyl)-1H-1,2,4-triazol-4-ium bromide, [HTz((pNO2Bz)2)]Br, has been synthesized and used in the synthesis of the corresponding metal complexes M[Tz((pNO2Bz)2)]Br (M = Cu(I), Ag(I) or Au(I)). These compounds were characterized by several spectroscopic techniques including NMR and mass spectroscopy. The complete series of Au(I), Ag(I) and Cu(I) 1,2,4-triazole based NHC complexes has been synthesized aiming at a SAR study and at identifying the primary cellular targets accounting for their cytotoxic action. The cytotoxic properties of the NHC complexes have been assessed in various human cancer cell lines, including cisplatin sensitive and resistant cells, the most efficacious antiproliferative compound being Cu(I)-NHC, which was able to promote a growth inhibitory effect up to ten times higher than that promoted by cisplatin. A detailed analysis of molecular and cellular pharmacology allowed us to elucidate the role of the metallic core in determining the biological properties. In particular, gold(I) and silver(I) NHC complexes were found to be able to hamper mammalian thioredoxin reductase (TrxR) activity in human A431 cervical cancer cells, ultimately leading to a dramatic alteration of the cellular redox state and to the induction of cell death via apoptosis. Conversely, the copper NHC complex was found to be capable of inhibiting proteasome functionality thus determining the induction of a non-apoptotic cell death pathway.


Assuntos
Complexos de Coordenação/química , Compostos Heterocíclicos/química , Metano/análogos & derivados , Triazóis/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/toxicidade , Cobre/química , Ouro/química , Humanos , Ligantes , Metano/química , Microscopia Eletrônica de Transmissão , Oxirredução , Complexo de Endopeptidases do Proteassoma/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Tiorredoxina Dissulfeto Redutase/metabolismo
12.
Nanoscale ; 6(24): 14856-62, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25361034

RESUMO

Suspensions of bimetallic nanoparticles (NPs) of Ru and Cu have been synthesized by simultaneous decomposition of two organometallic compounds in an ionic liquid. These suspensions have been characterized by Anomalous Small-Angle X-ray Scattering (ASAXS) at energies slightly below the Ru K-edge. It is found that the NPs adopt a Ru-core, a Cu-shell structure, with a constant Ru core diameter of 1.9 nm for all Ru : Cu compositions, while the Cu shell thickness increases with Cu content up to 0.9 nm. The formation of RuCuNPs thus proceeds through rapid decomposition of the Ru precursor into RuNPs of constant size followed by the reaction of the Cu precursor and agglomeration as a Cu shell. Thus, the different decomposition kinetics of precursors make possible the elaboration of core-shell NPs composed of two metals without chemical affinity.

13.
Curr Med Chem ; 21(20): 2237-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24533815

RESUMO

Conventional chemotherapy and radiation treatment are two cornerstones of cancer treatment but efforts are required to improve their "therapeutic window". The development of metal complexes, including platinum, has had an enormous impact on current cancer chemotherapy. However, these chemotherapeutic drugs can be employed only in the management of a limited number of cancers and, furthermore, their use causes significant side effects. Research over the past 10 years has produced new complexes containing heavy atoms other than platinum, such as iron, cobalt, or gold, which have been used in phase I and phase II trials. Recent preclinical research has shown promising results also using titanium, ruthenium, copper and silver. The anticancer activity of metal-based compounds and nanoparticles (gold and gadolinium in particular) is presently under evaluation in several laboratories in combination with or without X-ray therapy. In fact, if present in sufficiently high concentrations in the tumors, metals can act as a radiotherapy adjuvant: they possess an increased capability to absorb the X-ray radiation with respect to the water-based tissues. Low energy electrons will be then released close to the metal and, therefore, determine a local dose enhancement. This review will focus on the anticancer properties of new drugs and on the rationale for testing their usefulness in combined treatment.


Assuntos
Antineoplásicos/uso terapêutico , Quimiorradioterapia , Metais/uso terapêutico , Neoplasias/terapia , Animais , Antineoplásicos/química , Humanos , Metais/química
14.
Phys Chem Chem Phys ; 16(5): 1967-76, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24336832

RESUMO

The energy storage market relating to lithium based systems regularly grows in size and expands in terms of a portfolio of energy and power demanding applications. Thus safety focused research must more than ever accompany related technological breakthroughs regarding performance of cells, resulting in intensive research on the chemistry and materials science to design more reliable batteries. Formulating electrolyte solutions with nonvolatile and hardly flammable ionic liquids instead of actual carbonate mixtures could be safer. However, few definitions of thermal stability of electrolytes based on ionic liquids have been reported in the case of abuse conditions (fire, shortcut, overcharge or overdischarge). This work investigates thermal stability up to combustion of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C1C4Im][NTf2]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([PYR14][NTf2]) ionic liquids, and their corresponding electrolytes containing lithium bis(trifluoromethanesulfonyl)imide LiNTf2. Their possible routes of degradation during thermal abuse testings were investigated by thermodynamic studies under several experimental conditions. Their behaviours under fire were also tested, including the analysis of emitted compounds.

15.
Clin Pharmacol Ther ; 94(6): 646-50, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23995267

RESUMO

Network medicine aims at unraveling cell signaling networks to propose personalized treatments for patients suffering from complex diseases. In this short review, we show the relevance of network medicine to cancer treatment by outlining the potential convergence points of the most recent technological and scientific developments in both drug design and signaling network analysis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desenho de Fármacos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Medicina de Precisão/métodos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biomarcadores/metabolismo , Humanos , Neoplasias/metabolismo , Mapas de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Biologia de Sistemas
16.
Sci Rep ; 2: 950, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23230515

RESUMO

Spinae are tubular surface appendages broadly found in Gram-negative bacteria. Little is known about their architecture, function or origin. Here, we report structural characterization of the spinae from marine bacteria Roseobacter sp. YSCB. Electron cryo-tomography revealed that a single filament winds into a hollow flared base with progressive change to a cylinder. Proteinase K unwound the spinae into proteolysis-resistant filaments. Thermal treatment ripped the spinae into ribbons that were melted with prolonged heating. Circular dichroism spectroscopy revealed a dominant beta-structure of the spinae. Differential scanning calorimetry analyses showed three endothermic transformations at 50-85°C, 98°C and 123°C, respectively. The heating almost completely disintegrated the spinae, abolished the 98°C transition and destroyed the beta-structure. Infrared spectroscopy identified the amide I spectrum maximum at a position similar to that of amyloid fibrils. Therefore, the spinae distinguish from other bacterial appendages, e.g. flagella and stalks, in both the structure and mechanism of assembly.


Assuntos
Extensões da Superfície Celular/ultraestrutura , Roseobacter/metabolismo , Varredura Diferencial de Calorimetria , Extensões da Superfície Celular/química , Extensões da Superfície Celular/fisiologia , Dicroísmo Circular , Microscopia Crioeletrônica , Temperatura
17.
Ann Chir Plast Esthet ; 57(1): 50-8, 2012 Feb.
Artigo em Francês | MEDLINE | ID: mdl-21237548

RESUMO

PURPOSE: Serosanguinous drainage after breast reconstruction by deep inferior epigastric perforator (DIEP) flap constitute with the microsurgical monitoring, the main limiting factors for patient discharge. Fibrin sealant has already been studied to reduce post breast surgery drainage. The authors are presenting their experience in secondary breast reconstruction by DIEP flap with the use of sprayed fibrin sealant. PATIENTS AND METHODS: Twenty-one female patients aged 28 to 63 years old who underwent secondary breast reconstruction after mastectomy for cancer between October 2004 and June 2007 have been reviewed. These patients were separated into two groups. In group 1, patients (n=9) received two drains placed under the flap and in the axillary area. In group 2, (n=12) the DIEP flaps and thoracic areas were sprayed with fibrin sealant (Tissucol(®)) before the two drains inset. RESULTS: No adverse effect were reported, with a 36-month median follow-up. Drainages volumes or durations were not correlated to the patients' Body Mass Index (BMI). Lower drained volumes were collected from the thoracic region (372ml versus 629mL) and thoracic drains were removed earlier (5.5 days versus 6.9 days) in group 2. The length of stay was also significantly reduced after fibrin sealant use (5.5 days versus 7.22 days with P=0.0305 by log rank test). CONCLUSION: This study is a rare clinical one on fibrin sealant use to decrease postoperative drainage in breast reconstruction by DIEP flap. Fibrin sealant significantly decreased the postoperative drainage volume and duration.


Assuntos
Drenagem , Artérias Epigástricas/transplante , Adesivo Tecidual de Fibrina , Mamoplastia/métodos , Cuidados Pós-Operatórios , Retalhos Cirúrgicos/irrigação sanguínea , Adesivos Teciduais , Adulto , Axila/cirurgia , Neoplasias da Mama/cirurgia , Feminino , Adesivo Tecidual de Fibrina/administração & dosagem , Seguimentos , Humanos , Tempo de Internação , Mastectomia Radical Modificada , Pessoa de Meia-Idade , Satisfação do Paciente , Reoperação , Estudos Retrospectivos , Adesivos Teciduais/administração & dosagem , Resultado do Tratamento
18.
Nanotechnology ; 22(39): 395202, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21891859

RESUMO

We investigate breakdown of carbon nanotube (CNT) interconnects induced by Joule heating in air and under high vacuum conditions (10(-5) mbar). A CNT with a diameter of 18 nm, which is grown by chemical vapor deposition to connect opposing titanium nitride (TiN) electrodes, is able to carry an electrical power up to 0.6 mW before breaking down under vacuum, with a corresponding maximum current density up to 8 × 10(7) A cm(-2) (compared to 0.16 mW and 2 × 10(7) A cm(-2) in air). Decoration with electrochemically deposited Ni particles allows protection of the CNT interconnect against oxidation and improvement of the heat release through the surrounding environment. A CNT decorated with Ni particles is able to carry an increased electrical power of about 1.5 mW before breaking down under vacuum, with a corresponding maximum current density as high as 1.2 × 10(8) A cm(-2). The Joule heating produced along the current carrying CNT interconnect is able to melt the Ni particles and promotes the formation of titanium carbon nitride which improves the electrical contact between the CNT and the TiN electrodes.

19.
J Plast Reconstr Aesthet Surg ; 64(1): e17-20, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20851068

RESUMO

Pyoderma gangrenosum (PG) is a non-infectious purulent ulcerative disease triggered mainly by chronic inflammatory bowel disease, monoclonal gammapathy, polyarthritis and haematological malignancies; exceptionally, it can be triggered by surgery alone. When PG is associated with fever, it can mimic infectious cellulitis. When it is located on the breast, unnecessary and deleterious surgical debridement may be performed. We present two cases of PG of the breast. The first is a postoperative PG and the second was associated with acute myeloid leukaemia - both led to unnecessary surgery. Several elements may have helped to make the diagnosis: nipples little affected by PG, symmetrical lesions on both breasts, other similar lesions elsewhere on the body, resistance to wide spectrum antibiotherapy, complete blood count abnormalities and negativity of bacterial culture. We propose an index to help the surgeon in his decision to realise a surgical debridement or to postpone it and consider the diagnosis of PG.


Assuntos
Mama/patologia , Leucemia Mieloide Aguda/diagnóstico , Mastectomia/métodos , Pioderma Gangrenoso/diagnóstico , Pioderma Gangrenoso/terapia , Úlcera Cutânea/diagnóstico , Corticosteroides/uso terapêutico , Adulto , Antibacterianos/uso terapêutico , Mama/cirurgia , Terapia Combinada , Desbridamento/métodos , Diagnóstico Diferencial , Diagnóstico Precoce , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/cirurgia , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Medição de Risco , Estudos de Amostragem , Índice de Gravidade de Doença , Úlcera Cutânea/terapia , Resultado do Tratamento , Cicatrização/fisiologia
20.
Ann Chir Plast Esthet ; 55(4): 302-6, 2010 Aug.
Artigo em Francês | MEDLINE | ID: mdl-20557991

RESUMO

The purpose of this anthropometric forward-looking study was to estimate the projection perceived by the previous edge of the latissimus dorsi muscle according to the morphology of the patients. Fifty women were included in this study. We performed thoracic measurements: chest (sub-mammary groove), waist and the middle-hip circumference measurement as well as the anterior rim projection, of the latissimus dorsi, felt at three levels: sub-mammary groove, waist as well as the middle-hip area. We then conducted studies on the variation of these measurements according to the morphology of the patients represented by the variation of the ratio circumference of waist/circumference of chest (TT/TP). By this, we concluded there exists in fact a correlation between the decrease of the ratio TT/TP and the recession of the perceived anterior rim of the latissimus dorsi. The more the report TT/TP decreases, the more the anterior rim of the latissimus dorsi is posterior. In conclusion, because the anterior rim of the latissimus dorsi is the main anatomical mark for the drawing of the musculocutaneous flap, it is therefore necessary to take extra care when assessing slim-waisted women: the drawing must be done in a posterior position.


Assuntos
Músculo Esquelético/anatomia & histologia , Parede Torácica/anatomia & histologia , Adolescente , Adulto , Idoso , Antropometria , Estatura , Índice de Massa Corporal , Peso Corporal , Procedimentos Cirúrgicos Dermatológicos , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Parede Torácica/cirurgia , Circunferência da Cintura , Relação Cintura-Quadril
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