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1.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-443693

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the third coronavirus in less than 20 years to spillover from an animal reservoir and cause severe disease in humans. High impact respiratory viruses such as pathogenic beta-coronaviruses and influenza viruses, as well as other emerging respiratory viruses, pose an ongoing global health threat to humans. There is a critical need for physiologically relevant, robust and ready to use, in vitro cellular assay platforms to rapidly model the infectivity of emerging respiratory viruses and discover and develop new antiviral treatments. Here, we validate in vitro human alveolar and tracheobronchial tissue equivalents and assess their usefulness as in vitro assay platforms in the context of live SARS-CoV-2 and influenza A virus infections. We establish the cellular complexity of two distinct tracheobronchial and alveolar epithelial air liquid interface (ALI) tissue models, describe SARS-CoV-2 and influenza virus infectivity rates and patterns in these ALI tissues, the viral-induced cytokine production as it relates to tissue-specific disease, and demonstrate the pharmacologically validity of these lung epithelium models as antiviral drug screening assay platforms.

3.
Nat Microbiol ; 6(1): 73-86, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340034

RESUMO

Non-human primate models will expedite therapeutics and vaccines for coronavirus disease 2019 (COVID-19) to clinical trials. Here, we compare acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in young and old rhesus macaques, baboons and old marmosets. Macaques had clinical signs of viral infection, mild to moderate pneumonitis and extra-pulmonary pathologies, and both age groups recovered in two weeks. Baboons had prolonged viral RNA shedding and substantially more lung inflammation compared with macaques. Inflammation in bronchoalveolar lavage was increased in old versus young baboons. Using techniques including computed tomography imaging, immunophenotyping, and alveolar/peripheral cytokine response and immunohistochemical analyses, we delineated cellular immune responses to SARS-CoV-2 infection in macaque and baboon lungs, including innate and adaptive immune cells and a prominent type-I interferon response. Macaques developed T-cell memory phenotypes/responses and bystander cytokine production. Old macaques had lower titres of SARS-CoV-2-specific IgG antibody levels compared with young macaques. Acute respiratory distress in macaques and baboons recapitulates the progression of COVID-19 in humans, making them suitable as models to test vaccines and therapies.


Assuntos
COVID-19/veterinária , Callithrix/imunologia , Pulmão/imunologia , Macaca mulatta/imunologia , Doenças dos Macacos/virologia , Papio/imunologia , SARS-CoV-2/imunologia , Imunidade Adaptativa , Animais , Anticorpos Antivirais/imunologia , Lavagem Broncoalveolar , Líquido da Lavagem Broncoalveolar , COVID-19/diagnóstico por imagem , COVID-19/imunologia , COVID-19/patologia , Feminino , Humanos , Imunidade Celular/imunologia , Imunoglobulina G/imunologia , Inflamação/patologia , Pulmão/virologia , Masculino , Doenças dos Macacos/imunologia , Células Mieloides/imunologia , Carga Viral , Eliminação de Partículas Virais
6.
Transfus Clin Biol ; 25(2): 118-135, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29625790

RESUMO

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.


Assuntos
Segurança do Sangue , Transfusão de Sangue/normas , Reação Transfusional , Humanos , Risco
7.
Rev. otorrinolaringol. cir. cabeza cuello ; 77(3): 307-310, set. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-902781

RESUMO

Mujer de 68 años que ingresa en la Unidad de Cuidados Intensivos por shock séptico. En el posoperatorio la paciente se mantiene inestable y se decide realizar traqueotomía percutánea (TP) por intubación prolongada. Al inicio la paciente presenta un enfisema subcutáneo que progresa hasta convertirse en masivo. Se realiza TC torácico donde se observa pérdida de la morfología habitual de la pared posterior traqueal con solución de continuidad. Tras revisión mediante traqueobroncoscopía se decide colocar cánula de traqueotomía larga para dejar la lesión proximal al neumotaponamiento y así evitar la fuga de aire. Desde la colocación de la nueva cánula, la paciente presenta una disminución progresiva del enfisema hasta su total resolución. La TP es un procedimiento seguro que se realiza con mucha frecuencia en los servicios de medicina intensiva, sin embargo, no está exenta de complicaciones. En la revisión de Powell y cols describen las complicaciones de la TP destacando la inserción peritraqueal, la hemorragia, las infecciones de la herida, el neumotórax y la muerte. El rango de complicaciones en la literatura oscila entre 3% y 18%. Además, no se encuentran diferencias significativas respecto a las complicaciones entre la TP y la técnica abierta.


A 68-year-old woman who enter in intensive care unit due to septic shock. In the postoperative period, the patient remained unstable and decided to perform a percutaneous tracheotomy (PT) because prolonged intubation. In the first, the patient presents subcutaneous emphysema that progresses until becoming massive. Thoracic CT is performed where loss of the usual morphology of the posterior tracheal wall with continuity solution is observed. After revision by means of tracheobroncoscopia, it is decided to place a long tracheotomy cannula to leave the lesion proximal to pneumotaponamiento and thus avoid air leakage. From the placement of the new cannula, the patient presents a progressive decrease of the emphysema until its total resolution. PD is a safe procedure that is performed very frequently in the Intensive Care Services3, however, it is not without its complications. The review of Powell et al4 describes the complications of PT emphasizing peritracheal insertion, hemorrhage, wound infections, pneumothorax, and death. The range of complications in the literature ranges from 3 to 18% 5. In addition, no significant differences were found regarding the complications between the TP and the open technique.


Assuntos
Humanos , Feminino , Idoso , Pneumotórax/etiologia , Enfisema Subcutâneo/etiologia , Traqueotomia/efeitos adversos , Enfisema Mediastínico/etiologia , Traqueotomia/métodos
10.
Arzneimittelforschung ; 62(12): 583-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23115059

RESUMO

Reactive oxygen species (ROS) are important mediators in a number of neurodegenerative diseases and molecules capable of scavenging ROS may be a feasible strategy for protecting neuronal cells. We previously demonstrated a powerful iron-chelating action of Guttiferone-A (GA), a naturally occurring polyphenol, on oxidative stress injuries initiated by iron overload. Here we addressed the neuroprotective potential of GA in hydrogen peroxide and glutamate-induced injury on rat's primary culture of cortical neurons and PC12 cells, respectively, and antioxidant properties concerning scavenging and anti-lipoperoxidative activities in cell-free models. The decrease in cell viability induced by each of the toxins, assessed by [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay, was significantly attenuated by GA. In addition, GA was found to be a potent antioxidant, as shown by (i) inhibition of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical reduction (EC50=20.0 µM), (ii) prevention against chemically or electrochemically generated superoxide radicals, (iii) inhibition of spontaneous brain lipid peroxidation and (iv) interference with the Fenton reaction. These results indicate that GA exerts neuroprotective effects against H2O2 or glutamate toxicity and its antioxidant activity, demonstrated in vitro, could be at least partly involved. They also suggest a promising potential for GA as a therapeutic agent against neurodegenerative diseases involving ROS and oxidative damage.


Assuntos
Benzofenonas/farmacologia , Sequestradores de Radicais Livres , Fármacos Neuroprotetores , Animais , Compostos de Bifenilo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Corantes , Eletroquímica , Frutas/química , Garcinia/química , Ácido Glutâmico/toxicidade , Humanos , Peróxido de Hidrogênio , Ferro , Peroxidação de Lipídeos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células PC12 , Picratos/metabolismo , Prenilação , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sais de Tetrazólio , Tiazóis
11.
Transfus Clin Biol ; 19(6): 338-44, 2012 Dec.
Artigo em Francês | MEDLINE | ID: mdl-23103422

RESUMO

CONTEXT: Among the adverse events in the blood transfusion process, transfusion to a "wrong" patient is potentially dangerous, as it can lead to an adverse reaction at least in case of ABO incompatible red cell concentrate. MATERIAL AND METHODS: The "Root Cause Analysis" working party of the National Hemovigilance Commission developed a tool to collect this type of adverse event, and tested it on a sample of 43 cases involving red cell concentrates notified between March, 2009 and February, 2010. RESULTS: One hundred and nine failures of a step in the transfusion process were observed, i.e. 2.5 failures per adverse event. Failures may occur early in the process. However, they are mainly found at the time of issuing of the blood component, and further, in the clinical ward. How the failure is eventually detected is not always described when the blood component has been fully transfused, in contrast with the cases where actual transfusion to the wrong patient has been prevented. Knowing the way of failure detection enables an objective approach of the efficacy of the numerous existing safety measures. In this sample, bedside controls (documents check as well as the use of anti-A and anti-B reagents with patient's blood and red cell concentrates) detected the failure in three cases out of 34, which were not detected before, showing an efficacy similar to the administrative control done at reception in the clinical ward. CONCLUSION: The document, set up to analyse step by step these cases of patient errors, will be used in the future to analyse all similar cases, not only with red cell concentrates, but also with platelet concentrates and fresh frozen plasma, ultimately in order to improve their prevention.


Assuntos
Segurança do Sangue , Transfusão de Eritrócitos , Erros Médicos/estatística & dados numéricos , Seleção de Pacientes , Humanos
13.
Transfus Clin Biol ; 18(4): 444-62, 2011 Aug.
Artigo em Francês | MEDLINE | ID: mdl-21724440

RESUMO

The will to reach for blood components a microbiological safety comparable to that of plasma-derived drugs led to the development of numerous pathogen reduction research programs for red blood cells and\or platelets in the 1990s. A consensus conference organized in 2007 allowed to define the main steps and precautions to be taken for the implementation of these processes. In the specific case of platelet concentrates, three processes stay this day in the run, even if they are not at the same development stage. A process using ultraviolet C only is at the stage of preclinical studies. The Mirasol® process, based on the activation of riboflavin by exposure to ultraviolet A and ultraviolet B is CE marked (class IIb), and a clinical study was published in 2010. The Intercept® process, involving the activation of a psoralen molecule by exposure to ultraviolet A, is CE marked (class III) since 2002, and has been licensed in France since 2005, in Germany since 2005 and in Switzerland since 2010. At least 12 clinical studies have been published. In regard to this last pathogen reduction process, the medical and scientific documentation, from in vitro investigations to post-marketing observational studies, is much more developed than the corresponding documentation of some innovative processes at the time of their generalization, such as the SAG-mannitol solution for red cell concentrates in 1979, leukoreduction filters for platelets and red cells concentrates in the 1990s, the solvent detergent therapeutic plasma in 1992 or the methylene blue therapeutic plasma in 2006.


Assuntos
Patógenos Transmitidos pelo Sangue , Controle de Infecções/métodos , Transfusão de Plaquetas/efeitos adversos , Humanos
15.
Transfus Clin Biol ; 17(5-6): 386-9, 2010 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21050788

RESUMO

Safety in the field of transfusion medicine has greatly improved in France. The risk of viral transmission has decreased by a factor greater than 1500 within the last 20 years. In comparison, the risk related to ABO error has decreased only by half. The reporting of critical incidents, which occur at any step of the transfusion procedure is now mandatory in France and is subject to an in-depth analysis, using methods close to that used in aviation safety. The goal of these analyses is to better understand human factors in order to implement more adequate prevention measures.


Assuntos
Segurança do Sangue , Causalidade , Reação Transfusional , Sistema ABO de Grupos Sanguíneos , Prevenção de Acidentes , Acidentes , Incompatibilidade de Grupos Sanguíneos/epidemiologia , Incompatibilidade de Grupos Sanguíneos/etiologia , Incompatibilidade de Grupos Sanguíneos/prevenção & controle , Patógenos Transmitidos pelo Sangue , França , Objetivos , Humanos , Erros Médicos/prevenção & controle , Viremia/etiologia , Viremia/prevenção & controle , Inativação de Vírus
17.
Transfus Clin Biol ; 16(2): 118-33, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-19443257

RESUMO

The quality of platelet concentrates had been greatly improved since the implementation of processing techniques based on the use of the buffy-coat in the years 1980. More recently, in the last 10 years, it is in the domain of safety that the greatest advances have been done, by the introduction of platelet additive solutions, on one hand, and by the progressive availability of pathogen reduction techniques, on the other hand. These developments in quality and safety of platelet components are important, as they lead to the conclusion that nowadays, apheresis platelet concentrates and pooled random donor platelet concentrates can be considered as equivalent, the only specific indication of the former being the care of HLA or HPA allo-immunized patients. This review covers the physiological basis of prophylactic and curative platelet transfusions, and the means to evaluate their efficacy. The main investigations that are necessary to perform in the event of an inefficient prophylactic transfusion are also mentioned. Platelet transfusion is an essential part of the transfusion support in case of central thrombocytopenia, and more indications in other medical and surgical situations are well defined. The vast majority of clinical situations in which platelet transfusions are indicated have been defined in the national guidelines published in 2003 by the AFSSAPS French authority, and are still fully valid today. Therefore, only some specific domains for which recent published data are questioning our present practices are discussed, such as the use of platelet concentrates in massive transfusion. Finally, three critical factors for establishing a coherent platelet transfusion strategy are developed: the transfusion trigger for prophylactic platelet transfusion, the platelet dose, and the impact of ABO compatibility between the product and the recipient.


Assuntos
Hemorragia/terapia , Transfusão de Plaquetas , Separação Celular , Transmissão de Doença Infecciosa/prevenção & controle , Humanos , Trombocitopenia/terapia
18.
Transfus Clin Biol ; 16(1): 21-9, 2009 Mar.
Artigo em Francês | MEDLINE | ID: mdl-19318287

RESUMO

During the years 1994-2001, a progressive decrease of the number of blood units transfused has been reported in France. In contrast, since 2002, there is an increasing number of blood units issuing (+7.6% between 2001 and 2006) and this must be investigated. On behalf of the French Society of Blood Transfusion, the "Recipients" working group promoted a nation wide survey with the support of the regional blood transfusion centres. This survey was aimed at describing the profiles of the transfused patients: socio-demographical patterns, and reasons of the blood transfusion (main and associated diagnoses). A cross-sectional survey was designed. All the patients who received a blood unit during a specific day were considered as the population of the study. They were identified by the regional transfusion centres by means of the "individual issuing form". Survey forms were fully filled for 90% of the patients. It has been considered as a good answer rate. Seven thousand four hundred and twenty-two blood units, delivered to 3450 patients were analyzed. Three groups of pathologies were found as a reason of transfusion: haematology-oncology (52.70% of the prescriptions) with 892 patients (27.8%) for haematological malignancies; surgical procedures (23.99%); intensive care and medicine procedures (21.92%). More than 50% of the recipients are 70 years old and more. This result is explained by the age distribution of inpatients. In a context of lack of donors and consequently difficulties to provide patients with optimal number of blood units, this study is helpful. Variability of blood unit issuings must be detected, analyzed and monitored in real time by the actors of the transfusion process, using computerized dashboards: the blood units provider (in order to adjust the strategy of blood units provision) and the health care establishment as well as care blood components prescribers (reasons of blood transfusion and evaluation of practices).


Assuntos
Bancos de Sangue/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Instalações de Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Grupos Diagnósticos Relacionados , Feminino , França , Pesquisas sobre Atenção à Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Arch Toxicol ; 83(1): 47-53, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18560806

RESUMO

One hypothesis for the etiology of cell damage arising from iron overload is that its excess selectively affects mitochondria. Here we tested the effects of acute iron overload on liver mitochondria isolated from rats subjected to a single dose of i.p. 500 mg/kg iron-dextran. The treatment increased the levels of iron in mitochondria (from 21 +/- 4 to 130 +/- 7 nmol/mg protein) and caused both lipid peroxidation and glutathione oxidation. The mitochondria of iron-treated rats showed lower respiratory control ratio in association with higher resting respiration. The mitochondrial uncoupling elicited by iron-treatment did not affect the phosphorylation efficiency or the ATP levels, suggesting that uncoupling is a mitochondrial protective mechanism against acute iron overload. Therefore, the reactive oxygen species (ROS)/H+ leak couple, functioning as a mitochondrial redox homeostatic mechanism could play a protective role in the acutely iron-loaded mitochondria.


Assuntos
Sobrecarga de Ferro/fisiopatologia , Complexo Ferro-Dextran/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Injeções Intraperitoneais , Sobrecarga de Ferro/induzido quimicamente , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias Hepáticas/metabolismo , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
20.
Vox Sang ; 94(1): 41-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18171328

RESUMO

BACKGROUND: Since 1998, prestorage leucoreduction of all cellular blood components has been made mandatory in France. The French blood service needed to follow the data on the quality of the blood components prepared by blood centres. MATERIAL AND METHODS: Quality control (QC) data were submitted to a central data bank by each blood centre. The data were stratified by preparation method for analysis of key performance criteria - residual white blood cell (WBC) and total haemoglobin content. The red blood cell (RBC) preparation processes and the methods for measuring haemoglobin content and residual WBC count were those routinely employed by blood centres. Each year, more than 15,500 RBCs were tested. RESULTS: Red blood cells had a mean haemoglobin content between 53.6 and 54.9 g/unit depending on the year (2001 to 2005). The requirement of 40 g/unit was reached for about 99% of units. The haemoglobin content was influenced by the preparation process: 56.8 +/- 6.9 vs. 50.6 +/- 5.6 g/unit in average for whole blood filtration or RBC filtration, respectively. Apheresis RBCs exhibited a reduced variability (51.8 +/- 3.1 g/unit). The median residual WBC count remained low (0.046 to 0.057 x 10(6) WBCs/unit), and the percentage of RBC units exceeding the 1 x 10(6) WBCs/unit cut-off ranged from 1.5 to 0.6% depending on the year. A seasonal pattern was observed, with a significant increase (P < 0.001) of the median residual WBC count and of the percent of non-conforming units during the summer months. CONCLUSION: Our QC data suggest an overall compliance with the standard. Our data bank is useful to inform on the performance of leucoreduced RBC preparation processes carried out with market available devices.


Assuntos
Eritrócitos , Procedimentos de Redução de Leucócitos/normas , Bancos de Sangue/normas , Citaferese , Transfusão de Eritrócitos/normas , Eritrócitos/química , Filtração , Seguimentos , França , Hemoglobinas/análise , Humanos , Procedimentos de Redução de Leucócitos/métodos , Controle de Qualidade , Estações do Ano
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