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1.
FASEB J ; 34(7): 8902-8919, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32519783

RESUMO

TOKs are outwardly rectifying K+ channels in fungi with two pore-loops and eight transmembrane spans. Here, we describe the TOKs from four pathogens that cause the majority of life-threatening fungal infections in humans. These TOKs pass large currents only in the outward direction like the canonical isolate from Saccharomyces cerevisiae (ScTOK), and distinct from other K+ channels. ScTOK, AfTOK1 (Aspergillus fumigatus), and H99TOK (Cryptococcus neoformans grubii) are K+ -selective and pass current above the K+ reversal potential. CaTOK (Candida albicans) and CnTOK (Cryptococcus neoformans neoformans) pass both K+ and Na+ and conduct above a reversal potential reflecting the mixed permeability of their selectivity filter. Mutations in CaTOK and ScTOK at sites homologous to those that open the internal gates in classical K+ channels are shown to produce inward TOK currents. A favored model for outward rectification is proposed whereby the reversal potential determines ion occupancy, and thus, conductivity, of the selectivity filter gate that is coupled to an imperfectly restrictive internal gate, permitting the filter to sample ion concentrations on both sides of the membrane.


Assuntos
Condutividade Elétrica , Ativação do Canal Iônico/fisiologia , Oócitos/fisiologia , Canais de Potássio/fisiologia , Potássio/metabolismo , Sequência de Aminoácidos , Animais , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Clonagem Molecular , Biologia Computacional , Cryptococcus neoformans/genética , Cryptococcus neoformans/crescimento & desenvolvimento , Cryptococcus neoformans/metabolismo , Potenciais da Membrana , Oócitos/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência , Xenopus laevis
2.
J Biol Chem ; 290(2): 889-903, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25425649

RESUMO

The calcium-activated chloride channel ANO1 regulates multiple physiological processes. However, little is known about the mechanism of channel gating and regulation of ANO1 activity. Using a high-throughput, random mutagenesis-based variomics screen, we generated and functionally characterized ∼6000 ANO1 mutants and identified novel mutations that affected channel activity, intracellular trafficking, or localization of ANO1. Mutations such as S741T increased ANO1 calcium sensitivity and rendered ANO1 calcium gating voltage-independent, demonstrating a critical role of the re-entrant loop in coupling calcium and voltage sensitivity of ANO1 and hence in regulating ANO1 activation. Our data present the first unbiased and comprehensive study of the structure-function relationship of ANO1. The novel ANO1 mutants reported have diverse functional characteristics, providing new tools to study ANO1 function in biological systems, paving the path for a better understanding of the function of ANO1 and its role in health and diseases.


Assuntos
Canais de Cloreto/metabolismo , Canais Iônicos/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Relação Estrutura-Atividade , Animais , Anoctamina-1 , Células CHO , Canais de Cloreto/química , Canais de Cloreto/genética , Cricetulus , Células HEK293 , Humanos , Canais Iônicos/química , Canais Iônicos/genética , Mutagênese Sítio-Dirigida , Proteínas de Neoplasias/genética , Conformação Proteica
3.
Proc Natl Acad Sci U S A ; 110(11): E1026-34, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23431153

RESUMO

The calcium-activated chloride channel anoctamin 1 (ANO1) is located within the 11q13 amplicon, one of the most frequently amplified chromosomal regions in human cancer, but its functional role in tumorigenesis has remained unclear. The 11q13 region is amplified in ∼15% of breast cancers. Whether ANO1 is amplified in breast tumors, the extent to which gene amplification contributes to ANO1 overexpression, and whether overexpression of ANO1 is important for tumor maintenance have remained unknown. We have found that ANO1 is amplified and highly expressed in breast cancer cell lines and primary tumors. Amplification of ANO1 correlated with disease grade and poor prognosis. Knockdown of ANO1 in ANO1-amplified breast cancer cell lines and other cancers bearing 11q13 amplification inhibited proliferation, induced apoptosis, and reduced tumor growth in established cancer xenografts. Moreover, ANO1 chloride channel activity was important for cell viability. Mechanistically, ANO1 knockdown or pharmacological inhibition of its chloride-channel activity reduced EGF receptor (EGFR) and calmodulin-dependent protein kinase II (CAMKII) signaling, which subsequently attenuated AKT, v-src sarcoma viral oncogene homolog (SRC), and extracellular signal-regulated kinase (ERK) activation in vitro and in vivo. Our results highlight the involvement of the ANO1 chloride channel in tumor progression and provide insights into oncogenic signaling in human cancers with 11q13 amplification, thereby establishing ANO1 as a promising target for therapy in these highly prevalent tumor types.


Assuntos
Neoplasias da Mama/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Canais de Cloreto/metabolismo , Cromossomos Humanos Par 11/metabolismo , Amplificação de Genes , Proteínas de Neoplasias/metabolismo , Animais , Anoctamina-1 , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Canais de Cloreto/genética , Cromossomos Humanos Par 11/genética , Ativação Enzimática/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Transdução de Sinais/genética , Transplante Heterólogo
4.
Biopolymers ; 101(3): 228-36, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23784667

RESUMO

Maleic anhydride (CMA) and itaconic anhydride modified collagen (CITA) were prepared as precursors for production of interpenetrated polymer networks (IPN). Calculated values for Huggins coefficient in aqueous diluted and semi-diluted solutions of modified collagen indicated a slightly tendency of aggregation for itaconic anhydride-modified collagen. In semi-diluted solution collagen (Coll) and CMA present slightly differences in the thixotropic behavior, while CITA has a pronounced thixotropic behavior. Flow and oscillatory measurements revealed an elastic behavior of the collagen solutions, pure and modified with MA or ITA, as the storage modulus (G') has always a superior value compared with the loss modulus (G″). The denaturation temperature (Td) of unmodified collagen increased from 34°C to 40°C for CMA and to 39°C for CITA respectively, by formation of covalent bonds that stabilize the triple helix.


Assuntos
Anidridos , Reologia , Anidridos/química , Colágeno/química , Soluções , Temperatura , Viscosidade
5.
Phys Chem Chem Phys ; 16(47): 25896-905, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25355433

RESUMO

The study proposes modeling calcein release kinetics (considered as a hydrophilic drug model) from an interpenetrating network matrix of hydrogels, based on the combination of two polymers, of which chitosan is the most commonly used polymer. The release process is analyzed for different increasing time intervals, based on the evolution of the release kinetics. For each time interval, a dominant release mechanism was identified and quantitative analyses were performed, to probe the existence of four distinct stages during its evolution with each stage governed by a different kinetics model. An interesting and original aspect, which is analyzed through a novel approach, is that of drug release at longer time scales, which is often overlooked. It revealed that the system behaves as a complex one and its evolution can be described through a nonlinear theoretical model, which offers us new insights into its order-disorder evolution.


Assuntos
Quitosana/química , Fluoresceínas/química , Hidrogéis/química , Cinética , Modelos Moleculares
6.
J Nanosci Nanotechnol ; 14(7): 5473-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24758052

RESUMO

The photoluminescence properties and formation mechanism of a novel stoichiometric phosphor are presented. Nanoplates of pure single-phase crystalline Eu2O2CO3 oxycarbonate (hexagonal type-II) were synthesized by dry autoclaving under autogenic pressure (under 3 MPa) using an efficient, high yield solid state green-chemistry route that can be extended to other rare-earth oxycarbonate and oxide systems, resulting in the full conversion of a simple commercial precursor in single-crystalline nanoplates with strong visible luminescence. Phosphors made of an oxide host and an active luminescent dopant ion are the commercial standard (i.e., Y2O3:Eu). It is generally considered that the activity of luminescent species, such as Eu3+, is quenched and disappears above a certain concentration of them in the lattice (concentration quenching). The truly stoichoimetric oxycarbonate phosphor without active dopant ions exhibits very strong red emission when excited by different excitations, in the UV and visible range, without any concentration quenching effect. The bright red light emission spectra of the of the photo-excited phosphor nanoplates under UV and visible light excitation is compared with that of a standard Y2O3:Eu commercial red phosphor powder, and the thermal conversion mechanism is proposed to obtain the single-phase stable stoichiometric oxycarbonate nanoplates.

7.
Clin Res Cardiol ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112744

RESUMO

INTRODUCTION: The eradication of ventricular tachycardia (VT) isthmus sites constitutes the minimal procedural endpoint for VT ablation procedures. Contemporary high-resolution computed tomography (CT) imaging, in combination with computer-assisted analysis and segmentation of CT data, facilitates targeted elimination of VT isthmi. In this context, inHEART offers digitally rendered three-dimensional (3D) cardiac models which allow preoperative planning for VT ablations in ischemic and non-ischemic cardiomyopathies. To date, almost no data have been collected to compare the outcomes of VT ablations utilizing inHEART with those of traditional ablation approaches. METHODS: The presented data are derived from a retrospective analysis of n = 108 patients, with one cohort undergoing VT ablation aided by late-enhancement CT and subsequent analysis and segmentation by inHEART, while the other cohort received ablation through conventional methods like substrate mapping and activation mapping. The ablations were executed utilizing a 3D mapping system (Carto3), with the mapping generated via the CARTO® PENTARAY™ NAV catheter and subsequently merged with the inHEART model, if available. RESULTS: Results showed more successful outcome of ablations for the inHEART group with lower VT recurrence (27% vs. 42%, p < 0.06). Subsequent analyses revealed that patients with ischemic cardiomyopathies appeared to derive a significant benefit from inHEART-assisted VT ablation procedures, with a higher rate of successful ablation (p = 0.05). CONCLUSION: Our findings indicate that inHEART-guided ablation is associated with reduced VT recurrence compared to conventional procedures. This suggests that employing advanced imaging and computational modeling in VT ablation may be valuable for VT recurrences.

8.
Geohealth ; 7(10): e2023GH000901, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37799773

RESUMO

The objective of this study was to identify spatial disparities in the distribution of cancer hotspots within Romania. Additionally, the research aimed to track prevailing trends in cancer prevalence and mortality according to a cancer type. The study covered the timeframe between 2008 and 2017, examining all 3,181 territorial administrative units. The analysis of spatial distribution relied on two key parameters. The first parameter, persistence, measured the duration for which cancer prevalence exceeded the 75th percentile threshold. Cancer prevalence refers to the total number of individuals in a population who have been diagnosed with cancer at a specific time point, including both newly diagnosed cases (occurrence) and existing cases. The second parameter, the time continuity of persistence, calculated the consecutive months during which cancer prevalence consistently surpassed the 75th percentile threshold. Notably, persistence of elevated values was also evident in lowland regions, devoid of any discernible direct connection to environmental conditions. In conclusion, this work bears substantial relevance to regional health policies, by aiding in the formulation of prevention strategies, while also fostering a deeper comprehension of the socioeconomic and environmental factors contributing to cancer.

9.
Acta Chir Belg ; 112(3): 209-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808761

RESUMO

BACKGROUND: The treatment of gastric cancer is currently based on open gastric resection and regional lymph node dissection. Although the minimally invasive approach is currently being adopted for ever more complex procedures in order to improve post-operative outcomes, the laparoscopic radical D2 gastrectomy has not yet gained a wide acceptance, it being considered one of the most difficult operations in general surgery. Robotic surgery is better than the conventional laparoscopic approach, in that it avoids some of its limitations. Wristed instruments with seven degrees of freedom, the tremor filtering system, the ability to scale motion, and tridimensional vision improve the surgeons' dexterity when a fine manipulation of tissues in a narrow, fixed operating field or handsewn sutures are required. This study will attempt to evaluate the feasibility of robotic total and subtotal gastrectomy for locally advanced gastric cancer. METHODS: Two patients with locally advanced gastric adenocarcinoma underwent robot-assisted gastrectomy with D2 lymph node dissection, with no open or laparoscopic conversion. RESULTS: The post-operative evolution was uneventful and they were both discharged without complications. The number of lymph nodes retrieved was comparable to open surgery. Currently, after a follow-up period of 23 and 26 months respectively, both patients are disease-free. CONCLUSIONS: Robotic surgery can be a simpler way of expanding the indications of minimally invasive surgery so as to include the advanced gastric cancer. However, controlled prospective studies are needed in order to evaluate the role of robotics in the management of gastric cancer.


Assuntos
Adenocarcinoma/cirurgia , Gastrectomia , Laparoscopia , Robótica , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Neoplasias Gástricas/patologia , Resultado do Tratamento
10.
J Interv Card Electrophysiol ; 65(2): 491-497, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35748975

RESUMO

BACKGROUND: High-power short-duration (HPSD) radiofrequency ablation (RFA) is highly efficient and safe while reducing procedure and RF time in pulmonary vein isolation (PVI). The QDot™ catheter is a novel contact force ablation catheter that allows automated flow and power adjustments depending on the local tissue temperature to maintain a target temperature during 90 W/4 s lesions. We analysed intraprocedural data and periprocedural safety using the QDot-catheter in patients undergoing PVI for paroxysmal atrial fibrillation (PAF). METHODS: We included n = 48 patients undergoing PVI with the QDot-catheter with a temperature-controlled HPSD ablation mode with 90 W/4 s (TC-HPSD). If focal reconnection occurred besides repeat ablation, the ablation mode was changed to 50 W/15 s (QMode). N = 23 patients underwent cerebral MRI to detect silent cerebral lesions. RESULTS: Mean RF time was 8.1 ± 2.8 min, and procedure duration was 84.5 ± 30 min. The overall maximal measured catheter tip temperature was 52.0 °C ± 4.6 °C, mean overall applied current was 871 mA ± 44 mA and overall applied energy was 316 J ± 47 J. The mean local impedance drop was 12.1 ± 2.4 Ohms. During adenosine challenge, n = 14 (29%) patients showed dormant conduction. A total of n = 24 steam pops were detected in n = 18 patients (39.1%), while no pericardial tamponade occurred. No periprocedural thromboembolic complications occurred, while n = 4 patients (17.4%) showed silent cerebral lesion. CONCLUSIONS: TC-HPSD ablation with 90 W/4 s using the QDot-catheter led to a reduction of procedure and RF time, while no major complications occurred. Despite optimized temperature control and power adjustment, steam pops occurred in a rather high number of patients, while none of them leads to tamponade or to clinical or neurological deficits.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Temperatura , Vapor , Desenho de Equipamento , Ablação por Cateter/métodos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Imageamento por Ressonância Magnética , Resultado do Tratamento
11.
Eur Rev Med Pharmacol Sci ; 26(18): 6796-6804, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36196728

RESUMO

OBJECTIVE: Cardiovascular atherosclerotic comorbidities represent an important cause of morbidity and mortality in patients diagnosed with psoriatic arthritis. In both atherosclerosis and Psoriatic arthritis, inflammation plays a pivotal role. Psoriatic arthritis is considered as an independent risk factor for the development of atherosclerosis with accelerated evolution. Development of atherosclerosis is initiated by the endothelial cell dysfunction along with inflammation and insulin resistance. The main aim of the study was to evaluate the endothelial function in Psoriatic arthritis patients, and to identify if it is related to the insulin resistance and Psoriatic arthritis disease activity. PATIENTS AND METHODS: In this case-control study, a group of 32 age and gender matched healthy controls was formed and compared to the group of 32 Psoriatic arthritis patients. We assessed the following parameters: Disease Activity in Psoriatic Arthritis Score, Homeostatic Model Assessment for Insulin Resistance, serum levels of the tumor necrosis factor alpha (TNFα), and the endothelial dysfunction by means of the flow-mediated dilation at brachial artery. The Student's t-test, the Pearson correlation and the ANOVA test were used to perform the statistical analysis of the data obtained; p-value <0.05 was considered as statistically significant. RESULTS: Compared to the patients in the control group, TNFα and Homeostatic Model Assessment for Insulin Resistance were increased (p-value <0.001), and flow-mediated dilation at brachial artery was decreased (p-value <0.001) in the disease group. In Psoriatic arthritis patients, significant correlations were found between Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance (r=0.8143, p-value <0.001), and between Disease Activity in Psoriatic Arthritis Score and flow-mediated dilation at brachial artery % (r= -0.8376, p-value <0.001). Psoriatic arthritis patients treated with Methotrexate exhibited reduced values of Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance and increased values of flow-mediated dilation at brachial artery, when compared with the untreated patients. CONCLUSIONS: Endothelial dysfunction is present in Psoriatic arthritis patients and has a significant correlation with both, the course of the disease and the insulin resistance.


Assuntos
Artrite Psoriásica , Aterosclerose , Resistência à Insulina , Artéria Braquial , Estudos de Casos e Controles , Endotélio Vascular , Humanos , Inflamação , Metotrexato , Fator de Necrose Tumoral alfa
12.
Epidemiol Psychiatr Sci ; 31: e39, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35674122

RESUMO

AIMS: As refugees and asylum seekers are at high risk of developing mental disorders, we assessed the effectiveness of Self-Help Plus (SH + ), a psychological intervention developed by the World Health Organization, in reducing the risk of developing any mental disorders at 12-month follow-up in refugees and asylum seekers resettled in Western Europe. METHODS: Refugees and asylum seekers with psychological distress (General Health Questionnaire-12 ⩾ 3) but without a mental disorder according to the Mini International Neuropsychiatric Interview (M.I.N.I.) were randomised to either SH + or enhanced treatment as usual (ETAU). The frequency of mental disorders at 12 months was measured with the M.I.N.I., while secondary outcomes included self-identified problems, psychological symptoms and other outcomes. RESULTS: Of 459 participants randomly assigned to SH + or ETAU, 246 accepted to be interviewed at 12 months. No difference in the frequency of any mental disorders was found (relative risk [RR] = 0.841; 95% confidence interval [CI] 0.389-1.819; p-value = 0.659). In the per protocol (PP) population, that is in participants attending at least three group-based sessions, SH + almost halved the frequency of mental disorders at 12 months compared to ETAU, however so few participants and events contributed to this analysis that it yielded a non-significant result (RR = 0.528; 95% CI 0.180-1.544; p-value = 0.230). SH + was associated with improvements at 12 months in psychological distress (p-value = 0.004), depressive symptoms (p-value = 0.011) and wellbeing (p-value = 0.001). CONCLUSIONS: The present study failed to show any long-term preventative effect of SH + in refugees and asylum seekers resettled in Western European countries. Analysis of the PP population and of secondary outcomes provided signals of a potential effect of SH + in the long-term, which would suggest the value of exploring the effects of booster sessions and strategies to increase SH + adherence.


Assuntos
Transtornos Mentais , Angústia Psicológica , Refugiados , Transtornos de Estresse Pós-Traumáticos , Europa (Continente) , Comportamentos Relacionados com a Saúde , Humanos , Transtornos Mentais/epidemiologia , Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia
13.
Roum Arch Microbiol Immunol ; 70(1): 11-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21717806

RESUMO

The aim of this study was to assess the antibacterial and antifungal potential of some Romanian medicinal plants, arnica--Arnica montana, wormwood--Artemisia absinthium and nettle--Urtica dioica. In order to perform this antimicrobial screening, we obtained the vegetal extracts and we tested them on a series of Gram-positive and Gram-negative bacteria, and also against two fungal strains. The vegetal extracts showed antimicrobial activity preferentially directed against the planktonic fungal and bacterial growth, while the effect against biofilm formation and development was demonstrated only against S. aureus and C. albicans. Our in vitro assays indicate that the studied plant extracts are a significant source of natural alternatives to antimicrobial therapy, thus avoiding antibiotic therapy, the use of which has become excessive in recent years.


Assuntos
Anti-Infecciosos/farmacologia , Plâncton/efeitos dos fármacos , Extratos Vegetais/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Plantas Medicinais , Romênia
14.
Oftalmologia ; 55(4): 92-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22642143

RESUMO

Nowadays the management of ocular diseases is limited by the inability for controlled drug delivery. In the present study micro and nanoparticles based on Chitosan labeled with fluorescein, prepared by double crosslinking method in water/oil emulsion, were investigated as a new vehicle for intraocular drug delivery. The main objective was to study the biodistribution of the prepared particles after beind administered into the anterior chamber of pig eyes. Nanoparticles were characterized by Scanning Electron Microscopy Laser Difractometry and analysis was performed by Confocal Laser Microscopy. The designed micro and nanoparticles have average size from 500 nm to 2 microm and present round shape, smooth surface, relative high dimensional poly-dispersity and relative high porosity. The particles also present good biodistribution at corneal, scleral, retinal and optic nerve level after being administered. After this eliminary phase we intend to use Chitosan based nanoparticles as a controlled drug delivery system for therapies concerning endophthalmitis, age related macular degeneration etc.


Assuntos
Quitosana/administração & dosagem , Olho/metabolismo , Nanopartículas/administração & dosagem , Veículos Farmacêuticos/administração & dosagem , Animais , Química Farmacêutica , Quitosana/farmacocinética , Fluoresceína/administração & dosagem , Técnicas In Vitro , Microscopia Confocal , Microscopia Eletrônica de Varredura , Modelos Animais , Óleos/administração & dosagem , Soluções Oftálmicas/administração & dosagem , Sus scrofa , Água/administração & dosagem
15.
Sci Rep ; 11(1): 9591, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953282

RESUMO

Three commercial powders of MgB2 were tested in vitro by MTS and LDH cytotoxicity tests on the HS27 dermal cell line. Depending on powders, the toxicity concentrations were established in the range of 8.3-33.2 µg/ml. The powder with the lowest toxicity limit was embedded into polyvinylpyrrolidone (PVP), a biocompatible and biodegradable polymer, for two different concentrations. The self-replenishing MgB2-PVP composite materials were coated on substrate materials (plastic foil of the reservoir and silicon tubes) composing a commercial urinary catheter. The influence of the PVP-reference and MgB2-PVP novel coatings on the bacterial growth of Staphylococcus aureus ATCC 25923, Enterococcus faecium DMS 13590, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, in planktonic and biofilm state was assessed in vitro at 6, 24, and 48 h of incubation time. The MgB2-PVP coatings are efficient both against planktonic microbes and microbial biofilms. Results open promising applications for the use of MgB2 in the design of anti-infective strategies for different biomedical devices and systems.


Assuntos
Antibacterianos/farmacologia , Derme/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Povidona/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
16.
J Mater Sci Mater Med ; 21(4): 1211-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20033260

RESUMO

Nanostructured membranes and films of cationic surfactant-chitosan with tannic acid as polyphenol model were obtained by phase inversion method. The membranes were investigated by Attenuated Total Reflectance Fourier Transform InfraRred, X-Ray Diffraction, Scanning Electron Microscopy and Thermogravimetry, and the films topography was analysed by Atomic Force Microscopy. The analysis reveals that the interactions at the molecular level between cationic CTAB surfactant and cationic chitosan polymer strive to weaken membrane stability, whereas, the tannic acid is favoured to cluster with CTAB and diminish the membrane thermodynamic instability. The nanocapsules formed, with dimensions in the range of 16.35-27.68 nm, are congregating in clusters having dimensions in the domain of 50-300 nm. The layers resulted from these nanostructures arrangement constitute a surfactant-chitosan matrix with tannic acid suitable for drug controlled release with zero order kinetics.


Assuntos
Quitosana/química , Portadores de Fármacos/farmacocinética , Flavonoides/química , Nanocápsulas/química , Fenóis/química , Tensoativos/química , Algoritmos , Quitosana/farmacocinética , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Portadores de Fármacos/química , Flavonoides/farmacocinética , Cinética , Teste de Materiais , Membranas Artificiais , Microscopia de Força Atômica , Modelos Biológicos , Nanoestruturas/química , Fenóis/farmacocinética , Polifenóis , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/farmacocinética , Difração de Raios X
17.
J Mater Sci Mater Med ; 21(6): 1959-68, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20336353

RESUMO

One objective of this work was to study the corrosion resistance of the new implant Ti-10Zr-5Ta-5Nb alloy in physiological fluids of different pH values, simulating the extreme functional conditions. Another objective was in vitro biocompatibility evaluation of the new alloy using human fetal osteoblast cell line hFOB 1.19. Cytocompatibility was assessed by determination of possible material cytotoxic effects, cell morphology and cell adhesion. The thermo-mechanical processing of the new implant alloy consisted in plastic deformation (almost 90%) performed by hot rolling accompanied by an initial and final heat treatment. The new Ti-10Zr-5Ta-5Nb alloy presented self-passivation, with a large passive potential range and low passive current densities, namely, a very good anticorrosive resistance in Ringer solution of acid, neutral and alkaline pH values. Cell viability was not affected by the alloy substrate presence and a very good compatibility was noticed.


Assuntos
Próteses e Implantes , Titânio/química , Ligas/farmacologia , Líquidos Corporais/efeitos dos fármacos , Corrosão , Humanos , Soluções Isotônicas , Osteoblastos/efeitos dos fármacos , Solução de Ringer
18.
Chirurgia (Bucur) ; 105(1): 15-20, 2010.
Artigo em Ro | MEDLINE | ID: mdl-20405675

RESUMO

Thrombocytopenia is a common complication in patients with chronic liver disease and corelates with the severity of cirrhosis. Severe trombocytopenia can sinificantly increase the risk of spontaneous bleeding, but even if it is not symptomatic it can complicate the medical management of the cirrhotic patient by postponing diagnistic or therapeutic procedures (liver biopsy, interferon therapy, hepatocellular carcinoma resection). In consequence, numerous procedures were imagined to reverse thrombocytopenia associated with liver cirrhosis, among wich splenectomy. Due to the extreme invasiveness of the clasic approach in patients with hipersplenism (risk of bleeding, postoperative pain) especially in those with advanced cirrhosis, minimally invasive splenectomy appears to offer a safe and effective method for reversing thrombocytopenia in a highly selected group of patients with liver cirrhosis (Child A cirrhosis without other significant medical comorbid conditions). In these cases the surgical procedure is associated with low morbidity, blood loss and short hospital stay.


Assuntos
Laparoscopia , Cirrose Hepática/cirurgia , Esplenectomia , Trombocitopenia/cirurgia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Seleção de Pacientes , Índice de Gravidade de Doença , Trombocitopenia/diagnóstico , Trombocitopenia/etiologia , Resultado do Tratamento
19.
Roum Arch Microbiol Immunol ; 68(2): 95-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20361528

RESUMO

Aspergillosis is a fungal disease that may be expressed by a diversity of clinical syndromes being produced by several of more than 170 Aspergillus species. The "Matei Bals" National Institute for Infectious Diseases has a long experience in diagnostic procedures and treatment of the immunosuppressed patients. Irrespective of the place of their residence, most patients with HIV infection and AIDS were investigated in the Institute in the last two decades. The first case of double central nervous infection (Mycobacterium tuberculosis and Aspergillus fumigatus) in a HIV positive patient is discussed.


Assuntos
Aspergilose/microbiologia , Aspergillus fumigatus/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Meníngea/microbiologia , Adulto , Aspergilose/tratamento farmacológico , Aspergilose/imunologia , Feminino , Humanos , Hospedeiro Imunocomprometido , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Meníngea/imunologia
20.
Chirurgia (Bucur) ; 104(4): 425-9, 2009.
Artigo em Ro | MEDLINE | ID: mdl-19886050

RESUMO

Between 2002-2009, 25 cases of non-parasytic splenic cysts were treated in the Center of General Surgery and Liver Transplantation of Fundeni Clinical Institute. Among these cases, 11 patients were approached classically (8 total splenectomie and 3 partial cystectomies) and 14 patients were operated in a minimally invasive fashion (there were 3 total splenectomies, 2 subtotal splenectomies and 7 partial cystectomies, all accomplished laparoscopically, and one robotic total splenectomy and one robotic subtotal splenectomy). Recurrence rates vary according to the procedure. Laparoscopic partial cystectomy is a safe and feasible method, with minimal morbidity but with higher recurrence rates. The treatment of choice is the minimally invasive ideal cystectomy, achieved by laparoscopic partial splenectomy, that has the benefits of preserving the immune function of the spleen.


Assuntos
Cistos/cirurgia , Laparoscopia , Esplenectomia/métodos , Esplenopatias/diagnóstico , Esplenopatias/cirurgia , Adolescente , Adulto , Idoso , Cistos/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Doenças Parasitárias/diagnóstico , Doenças Parasitárias/cirurgia , Estudos Retrospectivos , Robótica/métodos , Prevenção Secundária , Resultado do Tratamento
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