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1.
Sci Rep ; 7(1): 5663, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28720833

RESUMO

Superconductivity and ferromagnetism are two antagonistic phenomena that combined can lead to a rich phenomenology of interactions, resulting in novel physical properties and unique functionalities. Here we propose an original hybrid system formed by a high-temperature superconducting film, patterned with antidots, and with ferromagnetic nano-rods grown inside them. This particular structure exhibits the synergic influence of superconductor (SC) - ferromagnetic (FM) stray fields, in both the superconducting behaviour of the film and the three-dimensional (3D) magnetic structure of nano-rods. We show that FM stray fields directly influence the critical current density of the superconducting film. Additional functionalities appear due to the interaction of SC stray fields, associated to supercurrent loops, with the non-trivial 3D remanent magnetic structure of FM nano-rods. This work unravels the importance of addressing quantitatively the effect of stray magnetic fields from both, the superconductor and the ferromagnet in hybrid magnetic nano-devices based on high temperature superconductors.

2.
J Small Anim Pract ; 58(3): 162-167, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28267217

RESUMO

OBJECTIVES: To compare the quality of duodenal and ileal samples obtained with different biopsy forceps. METHODS: Fifteen dogs were included in a prospective ex vivo study. After euthanasia, the duodenum and the ileum were sampled with four different forceps and evaluated according to a standardised scoring system. The biopsy forceps evaluated had alligator jaws or cups with smooth edge with or without a needle. RESULTS: The global quality of the biopsies was better in the ileum that in the duodenum regardless of the biopsy forceps. Biopsy forceps with smooth edge including a needle resulted in fewer artefacts than biopsy forceps with smooth edge but no needle in both sites and those with alligator jaws without a needle provided deeper biopsies than those with smooth edge without a needle only in the duodenum. There was no effect of the biopsy forceps type on the size of the biopsies. CLINICAL SIGNIFICANCE: Our findings may aid in choosing the appropriate type of forceps for intestinal biopsy.


Assuntos
Biópsia/veterinária , Instrumentos Cirúrgicos/veterinária , Animais , Biópsia/instrumentação , Cães , Duodeno/patologia , Íleo/patologia , Estudos Prospectivos
3.
BMC Pulm Med ; 16(1): 177, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27931198

RESUMO

BACKGROUND: Staging of mediastinal lymph nodes in non-small cell lung cancer (NSCLC) is mandatory. The maximum Standard Uptake Value (SUVmax) obtained using F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is the best non-invasive technique available for this evaluation, but its performance varies from center to center. The aim of the present study was to identify FDG-PET predictors of mediastinal malignancy that are able to minimize intercenter variability and improve the selection of subsequent staging procedures. METHOD: A multicenter study of NSCLC patients staged through FDG-PET and endobronchial ultrasonography with needle aspiration (EBUS-NA) was performed using therapeutic surgery with systematic nodal dissection as gold standard. Intercenter variability and predictive power for mediastinal malignancy of different FDG-PET measures were assessed, as well as the role of these measures for selecting additional staging procedures. RESULTS: One hundred and twenty-one NSCLC patients, of whom 94 (72%) had ≥1 hypermetabolic spots in the mediastinum, were included in the study. Mean SUVmax of the primary tumor was 12.3 (SD 6.3), and median SUVmax of the highest hypermetabolic spots in the mediastinum was 3.9 (IQR 2.4-7). Variability of FDG-PET measures between hospitals was statistically significant (p = 0.016 and p < 0.001 respectively), but lost significance when SUVmax in the mediastinum was expressed as a ratio or a subtraction from the primary tumor (SUVmax mediastinum/tumor, p = 0.083; and SUVmax mediastinum - tumor, p = 0.428 respectively). SUVmax mediastinum/tumor showed higher accuracy in the ROC analysis (AUC 0.77 CI 0.68-0.85, p < 0.001), and showed predictive power for mediastinal malignancy when using a 0.4 cutoff (OR 6.62, 95%CI 2.98-14.69). Sensitivities and negative predictive values of clinical staging through EBUS-NA attained values ranging between 57% and 92% after FDG-PET, which improved with additional techniques when the tumor had a diameter >3 cm and/or a SUVmax mediastinum/tumor ratio >0.4. CONCLUSION: The SUVmax mediastinum/tumor ratio is a good predictor of regional tumor extension in NSCLC. This measure is not influenced by intercenter variability and has an accuracy of over 70% for the identification of malignancy when using a 0.4 cutoff.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/secundário , Tomografia por Emissão de Pósitrons , Idoso , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Feminino , Fluordesoxiglucose F18 , Humanos , Modelos Logísticos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Masculino , Mediastino/diagnóstico por imagem , Mediastino/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Curva ROC , Espanha
6.
J Tissue Eng Regen Med ; 9(11): E76-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23420554

RESUMO

A major challenge of cardiac tissue engineering is directing cells to establish the physiological structure and function of the myocardium being replaced. Our aim was to examine the effect of electrical stimulation on the cardiodifferentiation potential of cardiac adipose tissue-derived progenitor cells (cardiac ATDPCs). Three different electrical stimulation protocols were tested; the selected protocol consisted of 2 ms monophasic square-wave pulses of 50 mV/cm at 1 Hz over 14 days. Cardiac and subcutaneous ATDPCs were grown on biocompatible patterned surfaces. Cardiomyogenic differentiation was examined by real-time PCR and immunocytofluorescence. In cardiac ATDPCs, MEF2A and GATA-4 were significantly upregulated at day 14 after stimulation, while subcutaneous ATDPCs only exhibited increased Cx43 expression. In response to electrical stimulation, cardiac ATDPCs elongated, and both cardiac and subcutaneous ATDPCs became aligned following the linear surface pattern of the construct. Cardiac ATDPC length increased by 11.3%, while subcutaneous ATDPC length diminished by 11.2% (p = 0.013 and p = 0.030 vs unstimulated controls, respectively). Compared to controls, electrostimulated cells became aligned better to the patterned surfaces when the pattern was perpendicular to the electric field (89.71 ± 28.47º for cardiac ATDPCs and 92.15 ± 15.21º for subcutaneous ATDPCs). Electrical stimulation of cardiac ATDPCs caused changes in cell phenotype and genetic machinery, making them more suitable for cardiac regeneration approaches. Thus, it seems advisable to use electrical cell training before delivery as a cell suspension or within engineered tissue.


Assuntos
Tecido Adiposo/citologia , Miocárdio/metabolismo , Células-Tronco/metabolismo , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Diferenciação Celular , Células Cultivadas , Terapia por Estimulação Elétrica , Humanos , Íons/química , Microscopia de Fluorescência , Miocárdio/patologia , Miócitos Cardíacos/citologia , Faloidina/química , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Regeneração , Transdução de Sinais , Células-Tronco/citologia , Regulação para Cima
7.
Rev. esp. pediatr. (Ed. impr.) ; 70(4): 205-208, jul.-ago. 2014. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-128381

RESUMO

La insuficiencia respiratoria es una de las causas principales de morbimortalidad en la unidad de cuidados intensivos neonatales (UCIN). Durante las últimas décadas ha habido un cambio sustancial en los avances en respiradores y tratatmientos médicos, así como en la supervivencia de neonatos de muy bajo peso. Sin embargo, el síndrome de fuga aérea pulmonar está todavía presente, incluso en aquellos con técnicas ventilatorias avanzadas. El síndrome de fuga aérea pulmonar (SFAP) se define como el escape de aire del árbol traqueobronquial hacia localizaciones donde normalmente no está presente. El SFAP lo conforman las siguientes entidades: el enfisema intersticial pulmonar, el neumotórax, el neumomediastino, el neumopericardio, el enfisema subcutáneo, el neumoperitoneo y el metabolismo gaseoso masivo. El factor de riesgo más importante es la inadecuada ventilación mecánica en neonatos con pulmonares inmaduros, aunque también puede ocurrir por los propios esfuerzos respiratorios del lactante, por maniobras de reanimación o por patología pulmonar subyacente. El objetivo de este trabajo es describir los patrones radiológicos de las distintas entidades que conforman el SFAP para poder reconocerlas, así como los factores de riesgo que aumentan la incidencia de esta entidad (AU)


Respiratory failure is one of the main causes of morbidity and mortality in the neonatal intensive care unit (NICU). During the last decades of medical ventilators treatments, as well as in survival rates of very low birth weight infants. However, pulmonary air leak syndrome is still present, even in cases with advanced ventilator techniques. Pulmonary air leak syndrome (PALS) is defined as a lead of air from the tracheobronchial tree towards locations where it is not usually presents. PALS comprises the following entities: pulmonary interstitial emphysema, pneumothorax, pneumomediastinum, pneumopericardium, subcutaneous emphysema, pneumoperitoneum and massive air embolism. The most important risk factor is inadequate mechanical ventilation in newborns with immature lungs, although it can also be caused by the respiratory efforts of the infant, by resuscitation procedures or by an underlying pulmonary pathology. The objective of this study id to describe the radiological pattern of the different entities that are part of PALS in order to be able to identify them, as well as to describe the risk factors that increase the incidence of this entity (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Insuficiência Respiratória/complicações , Insuficiência Respiratória/diagnóstico , Sacos Aéreos/patologia , Enfisema Subcutâneo , Fatores de Risco , Indicadores de Morbimortalidade , Recém-Nascido de Baixo Peso/metabolismo , Pneumoperitônio/patologia , Pneumoperitônio
8.
Eur J Clin Microbiol Infect Dis ; 33(7): 1101-11, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24449346

RESUMO

The bronchial microbiome in severe COPD during stability and exacerbation in patients chronically colonised by Pseudomonas aeruginosa (PA), has not been defined. Our objective was to determine the characteristics of the bronchial microbiome of severe COPD patients colonised and not colonised by P. aeruginosa and its changes during exacerbation. COPD patients with severe disease and frequent exacerbations were categorised according to chronic colonisation by P. aeruginosa. Sputum samples were obtained in stability and exacerbation, cultured, and analysed by 16S rRNA gene amplification and pyrosequencing. Sixteen patients were included, 5 of them showing chronic colonisation by P. aeruginosa. Pseudomonas genus had significantly higher relative abundance in stable colonised patients (p = 0.019), but no significant differences in biodiversity parameters were found between the two groups (Shannon, 3 (2-4) vs 3 (2-3), p = 0.699; Chao1, 124 (77-159) vs 140 (115-163), p = 0.364). In PA-colonised patients bronchial microbiome changed to a microbiome similar to non-PA-colonised patients during exacerbations. An increase in the relative abundance over 20 % during exacerbation was found for Streptococcus, Pseudomonas, Moraxella, Haemophilus, Neisseria, Achromobacter and Corynebacterium genera, which include recognised potentially pathogenic microorganisms, in 13 patients colonised and not colonised by P. aeruginosa with paired samples. These increases were not identified by culture in 5 out of 13 participants (38.5 %). Stable COPD patients with severe disease and PA-colonised showed a similar biodiversity to non-PA-colonised patients, with a higher relative abundance of Pseudomonas genus in bronchial secretions. Exacerbation in severe COPD patients showed the same microbial pattern, independently of previous colonisation by P. aeruginosa.


Assuntos
Brônquios/microbiologia , Microbiota , Doença Pulmonar Obstrutiva Crônica/microbiologia , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Estudos de Coortes , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Escarro/microbiologia
9.
J Chem Phys ; 139(3): 034701, 2013 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-23883046

RESUMO

Phthalocyanines, a class of macrocyclic, square planar molecules, are extensively studied as semiconductor materials for chemical sensors, dye-sensitized solar cells, and other applications. In this study, we use angular dependent near-edge x-ray absorption fine structure (NEXAFS) spectroscopy as a quantitative probe of the orientation and electronic structure of H2-, Fe-, Co-, and Cu-phthalocyanine molecular thin films. NEXAFS measurements at both the carbon and nitrogen K-edges reveal that phthalocyanine films deposited on sapphire have upright molecular orientations, while films up to 50 nm thick deposited on gold substrates contain prostrate molecules. Although great similarity is observed in the carbon and nitrogen K-edge NEXAFS spectra recorded for the films composed of prostrate molecules, the H2-phthalocyanine exhibits the cleanest angular dependence due to its purely out-of-plane π* resonances at the absorption onset. In contrast, organometallic-phthalocyanine nitrogen K-edges have a small in-plane resonance superimposed on this π* region that is due to a transition into molecular orbitals interacting with the 3dx(2)-y(2) empty state. NEXAFS spectra recorded at the metal L-edges for the prostrate films reveal dramatic variations in the angular dependence of specific resonances for the Cu-phthalocyanines compared with the Fe-, and Co-phthalocyanines. The Cu L3,2 edge exhibits a strong in-plane resonance, attributed to its b1g empty state with dx(2)-y(2) character at the Cu center. Conversely, the Fe- and Co- phthalocyanine L3,2 edges have strong out-of-plane resonances; these are attributed to transitions into not only b1g (dz(2)) but also eg states with dxz and dyz character at the metal center.

10.
Rev Sci Instrum ; 83(9): 093102, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23020357

RESUMO

We study the effect of photodiode angular response on the measurement of surface plasmon resonance (SPR) in metallic thin films using the Kretschmann-Raether configuration. The photodiode signal depends not only on the light intensity but also on the incidence angle. This implies that the photodiode sensitivity changes along the SPR curve. Consequently, the measured SPR spectrum is distorted, thus affecting fits and numerical analyses of SPR curves. We analyze the magnitude of this change, determine when it is significant, and develop a calibration method of the experimental setup which corrects for this type of spectral shape distortions.


Assuntos
Equipamentos e Provisões Elétricas , Ressonância de Plasmônio de Superfície/instrumentação , Compostos de Cálcio/química , Ouro/química , Indóis/química , Isoindóis , Óxidos/química , Hidróxido de Sódio/química
11.
Rev Sci Instrum ; 83(8): 083101, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22938268

RESUMO

We present an experimental setup for the simultaneous measurement of surface plasmon resonance (SPR) and x-ray absorption spectroscopy (XAS) on metallic thin films at a synchrotron beamline. The system allows measuring in situ and in real time the effect of x-ray irradiation on the SPR curves to explore the interaction of x-rays with matter. It is also possible to record XAS spectra while exciting SPR in order to study changes in the films induced by the excitation of surface plasmons. Combined experiments recording simultaneously SPR and XAS curves while scanning different parameters can be also carried out. The relative variations in the SPR and XAS spectra that can be detected with this setup range from 10(-3) to 10(-5), depending on the particular experiment.

12.
Plant Dis ; 95(7): 874, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30731724

RESUMO

In the fall of 2009, damping-off of Pinus radiata seedlings was observed in a pine nursery in Sant Feliu de Buixalleu, Girona Province, northeastern Spain. Plants exhibited needle blight, extensive root necrosis, and root death. Root sections of symptomatic plants were cut, washed under running tap water, surface disinfected for 1 min in a 1.5% sodium hypochlorite solution, and washed twice with sterile distilled water. Small fragments of discolored tissues were plated onto potato dextrose agar (PDA) supplemented with 0.5 g liter-1 of streptomycin sulfate. Plates were placed at 25°C in the dark for 10 to 14 days, and all fungal colonies were transferred to PDA. A Cylindrocarpon sp. was consistently isolated from necrotic root tissues. Single-conidial isolates were obtained and grown on PDA and Spezieller Nährstoffarmer agar (SNA) (2) at 25°C for 10 days with a 12-h photoperiod. On PDA, the isolates developed abundant mycelium, which varied from white-to-grayish brown or golden brown. On SNA, all isolates produced two-septate, (35-) 39.4 (-40) × (7.5-) 7.7 (-8.75) µm, and three-septate, (32.5-) 40.9 (-52.5) × (7.5-) 7.7 (-8.75) µm, macroconidia. Microconidia, one-septate macroconidia, and chlamydospores were not observed. Identity of these isolates was determined by a multiplex PCR system using a set of three pair of specific primers (Mac1/MaPa2, Lir1/Lir2, and Pau1/MaPa2) (1), which generated a 117-bp product that was characteristic of Cylindrocarpon pauciseptatum Schroers & Crous. Morphological characteristics also supported this identification (4). Internal transcribed spacers regions (ITS1 and ITS4) of rDNA were obtained for isolate 1052 and deposited in GenBank (Accession No. HQ441248). This sequence was identical (100%) with the sequence of C. pauciseptatum (GenBank Accession No. HM036590). Pathogenicity tests were conducted with inoculum produced on wheat kernels that were soaked in distilled water in flasks for 12 h. Each flask contained 200 ml of kernels that were subsequently autoclaved three times after excess water was drained. Two fungal disks from a 2-week-old culture of C. pauciseptatum (isolate 1052) grown on PDA were placed aseptically in each flask. Cultures in flasks were incubated at 25°C for 4 weeks and shaken once a week. A plastic pot (220 cm3) was filled with a mixture of sterilized peat moss and 10 g of inoculum. A 1-month-old seedling of P. radiata was planted in plastic pots and placed in a greenhouse at 25 to 30°C in a completely randomized design with six replications. Controls contained sterile wheat kernels. The experiment was repeated. Symptoms developed 20 days after inoculation and consisted of root lesions, a reduction in root biomass, needle blight, and the death of all seedlings. The fungus was reisolated from affected seedlings. Damping-off was not observed on the control plants. C. pauciseptatum causing black foot disease of grapevine (3) was first found in Spain in 2008, but to our knowledge, this is the first report of C. pauciseptatum causing damping-off of P. radiata in Spain. References: (1) S. Alaniz et al. Plant Dis. 93:821, 2009. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Oxford, 2006. (3) M. T. Martin et al. Plant Dis. 95:361, 2011. (4) H. J. Schroers et al. Mycol. Res. 112:82, 2008.

13.
Respir Med ; 95(10): 822-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11601749

RESUMO

The diagnosis of small peripheral lung cancer is difficult to achieve by non-invasive methods. We hypothesized that in these patients induced sputum might ncrease the diagnostic yield over spontaneous sputum, representing a good diagnostic alternative in selected patients. We prospectively evaluated 60 patients with peripheral lung lesions and normal bronchoscopic evaluation. Six samples of sputum (three spontaneous and three induced with nebulization of hypertonic saline) before bronchoscopy and six samples of sputum after bronchoscopy (three spontaneous and three induced) were obtained in each subject. Forty-two out of the 60 patients included were finally diagnosed with lung cancer. Eighteen patients were diagnosed with different benign conditions of the lung. Overall, malignant cells in sputum were observed in 21 patients and in all but one, the final diagnosis of lung cancer was achieved. Only one patient with a pseudoinflammatory tumour of the lung had a false-positive result in one spontaneous sputum sample. The diagnosis of lung cancer was obtained in 18 patients with the induced sputum (43%) and in 14 patients with spontaneous sputum (31%) (P=NS). Samples of induced sputum were more adequate for cytological analysis than samples of spontaneous sputum (P < 0.001). Of 13 patients with peripheral lung neoplasms of 2 cm or less in diameter, five were diagnosed using induced sputum (38%) and only one using spontaneous sputum (8%) (P<0.05). In conclusion, induced sputum is a valuable technique for the diagnosis of peripheral lung cancer. Induced sputum gives better quality specimens and better diagnostic yield in small lesions than the spontaneous sputum and may be indicated in selected patients with disseminated disease, inoperability or severe co-morbities.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Escarro/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Fumar , Manejo de Espécimes/métodos
14.
Respiration ; 68(4): 382-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11464085

RESUMO

BACKGROUND: Pulmonary nocardiosis is an infrequent infection whose incidence seems to be increasing due to a higher degree of clinical suspicion and the increasing number of immunosuppressive factors. OBJECTIVE: To study the predisposing factors, clinical characteristics, diagnostic procedures, treatment and progress of pulmonary nocardiosis (PN). METHODS: Review of 10 patients (9 male, 1 female, mean age 61) with PN in a 600-bed teaching hospital, diagnosed from 1992 to 1999. RESULTS: Associated diseases observed were chronic obstructive pulmonary disease (COPD) in 6 patients, human immunodeficiency virus (HIV) infection in 3 and polymyalgia rheumatica in 1. Four patients had received oral corticotherapy for COPD for over a year (mean dose 13 mg/day of prednisone or equivalent). The main reason for consultation was an increase in dyspnea in the patients with COPD (6/6) and fever in those with HIV (3/3). Mean time between onset of symptoms and diagnosis was 5 weeks. In 8 patients, the infection occurred outside the hospital setting. The infection was restricted to the lung in 9/10; in the remaining case, the central nervous system (CNS) and subcutaneous tissue were affected. Lobar or multilobar consolidation was the most frequent radiographic pattern found (6/10). Sputum culture was positive when performed (8 cases). Diagnosis was made or confirmed by bronchoscopy (bronchoaspirate or protected specimen brush) in 5 patients. Germs isolated were: Nocardia asteroides (8/10), Nocardia farcinica (1/10), Nocardia otitidiscaviarum (1/10). Cotrimoxazole was the most used empirical treatment (6/10). Resolution was achieved in 5 cases. Four subjects died: 1 HIV patient with disseminated nocardiosis, and 3 COPD patients, 2 of whom had received long-term corticotherapy. Illness recurred in only 1 case, due to failure to comply with treatment. CONCLUSIONS: (1) In our geographical setting Nocardia presents as a subacute or chronic pulmonary infection, mainly outside the hospital. (2) It tends to affect only the lung. (3) Diagnosis requires a high clinical suspicion, and can be made on the basis of a sputum culture. (4) Nocardia tends to attack patients with underlying COPD, or immunodepressed patients treated with glucocorticoids, or patients with HIV infection. (5) Mortality is high in both COPD and HIV patients. (6) In our area, cotrimoxazole seems to be the most commonly prescribed treatment.


Assuntos
Pneumopatias/microbiologia , Nocardiose , Infecções Respiratórias , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pneumopatias/diagnóstico , Pneumopatias/tratamento farmacológico , Pneumopatias Obstrutivas/complicações , Masculino , Pessoa de Meia-Idade , Nocardiose/complicações , Nocardiose/diagnóstico , Nocardiose/tratamento farmacológico , Nocardia asteroides , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/microbiologia , Estudos Retrospectivos
15.
Eur Respir J ; 17(2): 274-80, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11334131

RESUMO

Bronchoscopic bronchoalveolar lavage (BAL) may be followed by a systemic inflammatory response. Previous reports have suggested pneumonia as a predisposing condition and systemic cytokines as possible mediators. To test this hypothesis, systemic levels of interleukin (IL)-1beta, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were studied before and at 12 h and 24 h after bronchoscopically guided BAL in 30 mechanically ventilated patients (median age 67 (range 54-76) yrs, simplified acute physiology score II (SAPS II) 33 (12-56)), 20 of whom had pneumonia and 10 of whom were control patients without pneumonia. Arterial oxygen partial pressure to inspired oxygen fraction ratio (Pa,O2/FI,O2), body temperature, mean arterial pressure, and cardiac frequency were recorded. The majority of patients (28/30, 93%) received antibiotic treatment prior to the procedure. Pa,O2/FI,O2 ratio was lower at 12 h compared to baseline in patients with pneumonia (baseline median 192 (range 65-256); 12 h 160 (66-190) mmHg, p<0.001) and ventilated controls (baseline 293 (205-473); 12 h 226 (153-330) mm Hg p=0.011), but returned to baseline levels at 24 h (pneumonia: 194 (92-312), p=0.991; controls: 309 (173-487) mmHg, p=0.785). No changes in other clinical variables were observed. Systemic TNF-alpha levels before BAL (pneumonia: 35 (10-88); controls: 17 (0-33) pg x mL(-1)) did not increase at 12 h (pneumonia: 35 (0-64); p=0.735; controls: 16 (0-21) pg x mL(-1), p=0.123 comparison to baseline) or 24 h (pneumonia: 31 (0-36), p=0.464; controls: 19 (0-43) pg x mL(-1), p=0.358). No changes of IL-1beta (baseline: pneumonia 0 (0-13); controls 1 (0-32) pg x mL(-1)) or IL-6 (baseline: pneumonia, 226 (9-4300); controls, 53 (0-346) pg x mL(-1)) were detected. No deterioration of clinical variables and no increase in systemic cytokine release has been observed after bronchoalveolar lavage, in critically ill patients. The potential cytokine increase is probably too small, in relation to the pre-existing inflammatory response, to yield clinical significance in this population otherwise antibiotic therapy may have been protective.


Assuntos
Lavagem Broncoalveolar/efeitos adversos , Estado Terminal , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Idoso , Broncoscopia , Feminino , Humanos , Unidades de Terapia Intensiva , Interleucina-1/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Pneumonia/sangue , Pneumonia/microbiologia , Pneumonia/terapia , Respiração Artificial , Síndrome de Resposta Inflamatória Sistêmica/sangue , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Fator de Necrose Tumoral alfa/análise
18.
Thorax ; 55(1): 46-52, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10607801

RESUMO

BACKGROUND: The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia. METHODS: Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested. RESULTS: Serum TNF-alpha levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1beta and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1beta: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1beta: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1beta: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-alpha (standardised coefficient beta = 0.410, p<0.001) and IL-1beta (standardised coefficient beta = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model. CONCLUSIONS: Serum TNF-alpha levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-alpha and IL-1beta reflect the severity of the lung injury rather than the diagnosis.


Assuntos
Citocinas/metabolismo , Pneumonia/metabolismo , Síndrome do Desconforto Respiratório/metabolismo , Biomarcadores , Feminino , Humanos , Recém-Nascido , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo
19.
Crit Care Med ; 27(9): 1745-53, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10507593

RESUMO

OBJECTIVE: To assess the cytokine expression (tumor necrosis factor-alpha [TNF-alpha], interleukin [IL]-1beta, and IL-6) in severe pneumonia, both locally (in the lungs) and systemically (in blood). DESIGN: Prospective sequential study with bronchoalveolar lavage (BAL) and blood sampling. SETTING: Six-bed respiratory intensive care unit of a 1,000-bed teaching hospital. PATIENTS: Thirty mechanically ventilated patients (>48 hrs) were allocated to either the pneumonia group (n = 20) or a control group (n = 10). INTERVENTIONS: Protected specimen brush and BAL samples for quantitative cultures, and serum and BAL fluid TNF-alpha, IL-1beta, and IL-6 levels were measured on days 1, 3, and 7. In the control group, the procedure was done on day 1 only. MEASUREMENTS AND MAIN RESULTS: Serum TNF-alpha levels were significantly higher in patients with pneumonia compared with controls (35 +/- 4 vs. 17 +/- 3 pg/mL, respectively, p = .001). IL-6 levels in serum and BAL fluid were higher in pneumonia than in control patients (serum, 837 +/- 260 vs. 94 +/- 35 pg/mL, respectively, p = .017; BAL fluid, 1176 +/- 468 vs. 234 +/- 83 pg/mL, respectively, p = .05). On days 1, 3, and 7 in patients with pneumonia, IL-1beta levels turned out to be higher in BAL fluid than in serum (71 +/- 17 vs. 2 +/-1 pg/mL on day 1; 49 +/- 8 vs. 6 +/- 2 pg/mL on day 3; and 47 +/- 16 vs. 3 +/- 2 pg/mL on day 7 for BAL fluid and serum, respectively, p < .05). No significant correlation between BAL fluid cytokine levels and lung bacterial burden was shown in presence of antibiotic treatment. Although no clear relationship was found between BAL fluid and serum cytokines and mortality, there was a trend toward higher serum IL-6 levels in nonsurvivors (1209 +/- 433 pg/mL) with pneumonia compared with survivors (464 +/- 260 pg/mL). In addition, serum TNF-alpha and IL-6 correlated with multiple organ failure score (r2 = .36, p = .004 for both) and with lung injury score (r2 = .30, p = .01, and r2 = .22, p = .03, for TNF-alpha and IL-6, respectively). CONCLUSIONS: The present study describes the lung and systemic inflammatory response in severe pneumonia. The lung cytokine expression seems to be independent from the lung bacterial burden in the presence of antibiotic treatment. Because of the limited sample size, we did not find a clear relationship between serum and BAL fluid cytokine levels and outcome.


Assuntos
Líquido da Lavagem Broncoalveolar/imunologia , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Pneumonia/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Idoso , Análise de Variância , Líquido da Lavagem Broncoalveolar/citologia , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Contagem de Colônia Microbiana , Infecções Comunitárias Adquiridas/imunologia , Infecção Hospitalar/imunologia , Feminino , Humanos , Masculino , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Análise de Sobrevida
20.
Eur Respir J ; 14(1): 218-20, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10489855

RESUMO

The aim of the study was to assess the potential role of glucocorticoids (GC) in modulating systemic and pulmonary inflammatory responses in mechanically ventilated patients with severe pneumonia. Twenty mechanically ventilated patients with pneumonia treated at a respiratory intensive care unit (RICU) of a 1,000-bed teaching hospital were prospectively studied. All patients had received prior antimicrobial treatment. Eleven patients received GC (mean+/-SD dose of i.v. methylprednisolone 677+/-508 mg for 9+/-7 days), mainly for bronchial dilatation. Serum and bronchoalveolar lavage fluid (BALF) tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and C-reactive protein levels were measured in all patients. The inflammatory response was attenuated in patients receiving GC, both systemically (IL-6 1,089+/-342 versus 630+/-385 pg x mL(-1), p=0.03; C-reactive protein 34+/-5 versus 19+/-5 mg x L(-1), p=0.04) and locally in BALF (TNF-alpha 118+/-50 versus 24+/-5 pg x mL(-1), p= 0.05; neutrophil count: 2.4+/-1.1 x 10(9) cells x L(-1) (93+/-3%) versus 1.9+/-1.8 x 10(9) cells x L(-1) (57+/-16%), p=0.03). Four of the 11 (36%) patients receiving GC died compared to six (67%) who were not receiving GC (p=0.37). The present pilot study suggests that glucocorticoids decrease systemic and lung inflammatory responses in mechanically ventilated patients with severe pneumonia receiving antimicrobial treatment.


Assuntos
Glucocorticoides/uso terapêutico , Tolerância Imunológica , Metilprednisolona/uso terapêutico , Pneumonia Bacteriana/imunologia , Pneumonia Bacteriana/terapia , Antibacterianos/uso terapêutico , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Broncoconstrição/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Glucocorticoides/administração & dosagem , Hospitais de Ensino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Inflamação/imunologia , Injeções Intravenosas , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Contagem de Leucócitos , Metilprednisolona/administração & dosagem , Neutrófilos/patologia , Projetos Piloto , Pneumonia Bacteriana/metabolismo , Estudos Prospectivos , Respiração Artificial , Unidades de Cuidados Respiratórios , Fator de Necrose Tumoral alfa/metabolismo
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