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1.
Ocul Immunol Inflamm ; : 1-12, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687292

RESUMO

PURPOSE: To study the positivity rate of conjunctival realtime polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). DESIGN: Systematic review and diagnostic accuracy meta-analysis. METHODS: MEDLINE and EMBASE were queried using medical subject headings terms. Diagnostic accuracy meta-analyses and forest plots were obtained using the RevMan software. RESULTS: After deduplication, appraisal of abstract titles and full-text analysis of 1441 articles, 42 articles with 3351 COVID-19 patients were included in this review. Of these, 412 conjunctival swabs/Schirmer paper strips tested positive for SARS-CoV-2 by RT-PCR. The pooled sensitivity of the RT-PCR tests across the 24 studies with laboratory-confirmed COVID-19 patients was 10.3%. CONCLUSIONS: Only 1 in 10 RT-PCR tests performed on conjunctival swabs were positive for SARS-CoV-2. Although this suggests that SARS-CoV-2 is likely present and detectable in the conjunctiva, this detection method has low diagnostic potential.

2.
IEEE Trans Biomed Eng ; 71(1): 295-306, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37535482

RESUMO

Spectroscopy is a popular technique for identifying and quantifying fluorophores in fluorescent materials. However, quantifying the fluorophore of interest can be challenging when the material also contains other fluorophores (baseline), particularly if the emission spectrum of the baseline is not well-defined and overlaps with that of the fluorophore of interest. In this work, we propose a method that is free from any prior assumptions about the baseline by utilizing fluorescence signals at multiple excitation wavelengths. Despite the nonlinearity of the model, a closed-form expression of the least squares estimator is also derived. To evaluate our method, we consider the practical case of estimating the contributions of two forms of protoporphyrin IX (PpIX) in a fluorescence signal. This fluorophore of interest is commonly utilized in neuro-oncology operating rooms to distinguish the boundary between healthy and tumor tissue in a type of brain tumor known as glioma. Using a digital phantom calibrated with clinical and experimental data, we demonstrate that our method is more robust than current state-of-the-art methods for classifying pathological status, particularly when applied to images of simulated clinical gliomas. To account for the high variability in the baseline, we are examining various scenarios and their corresponding outcomes. In particular, it maintains the ability to distinguish between healthy and tumor tissue with an accuracy of up to 87%, while the ability of existing methods drops near 0%.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Ácido Aminolevulínico/química , Espectrometria de Fluorescência , Glioma/química , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Corantes Fluorescentes
3.
Encephale ; 47(4): 306-313, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33189347

RESUMO

OBJECTIVES: Alexithymia is a risk factor associated with a wide array of mental health issues and has been linked to a history of trauma including child sexual abuse. Yet, few measures evaluating alexithymia in children have been validated. This study aimed to explore the psychometric properties of the French version of the Children's Alexithymia Measure (CAM; Way et al., 2010) in a sample of sexually abused children. METHODS: A sample of 418 non-offending caregivers of sexually abused children aged 6 to 12 completed the Children's Alexithymia Measure. They were also invited to complete a series of questionnaires used as validity indices including the Emotion Regulation Checklist, the Child Behavior Checklist and the Child Dissociative Checklist. RESULTS: Both exploratory and confirmatory factor analyses supported the unidimensional factor structure of the Children's Alexithymia Measure and the total score showed high internal consistency. As expected, the total score of the Children's Alexithymia Measure was positively correlated with emotion regulation difficulties. In addition, the total score of the Children's Alexithymia Measure was found to be correlated with dimensions of both internalizing and externalizing behavior problems as well as dissociative symptoms, with children displaying higher scores of alexithymia showing higher symptoms. CONCLUSIONS: Findings provide initial support for the psychometric properties of the French version of the Children's Alexithymia Measure with a clinical sample of child victims of sexual abuse. The measure could be useful for future studies exploring the mediating role of alexithymia in the association between trauma and psychopathology. The measure could as well be a relevant tool in the clinical assessment of vulnerable children.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Sintomas Afetivos/diagnóstico , Sintomas Afetivos/epidemiologia , Criança , Maus-Tratos Infantis/diagnóstico , Humanos , Psicometria , Inquéritos e Questionários
4.
Opt Express ; 29(1): 219-231, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33362110

RESUMO

The bidirectional reflectance distribution function (BRDF) and the bidirectional scattering - surface reflectance distribution function (BSSRDF), which relate radiance at the surface to irradiance and radiant flux, respectively, are regarded as the most fundamental scattering quantities used to determine the reflectance of objects. However, for materials where the optical radiation is transmitted under the surface, this radiance depends not only on irradiance and radiant flux, but also on the size of the irradiated area of the surface. This article provides insight into such dependence under the special condition in which the radiance is evaluated within the irradiated area and, consequently, is produced by both the insurface reflection and the subsurface scattering, in contrast to the situation in which the radiance is evaluated at non-irradiated areas and only subsurface scattering contributes. By explicitly considering both contributions, two other scattering quantities are defined: one that accounts exclusively for the insurface reflection and the other that accounts for subsurface scattering. In this regard, these quantities might be considered more fundamental than the BRDF and the BSSRDF, although they are coincident with these two functions apart from the above-mentioned special condition and for materials with negligible subsurface scattering. In this work, the relevance of the proposed scattering quantities is supported by experimental data, practical considerations are given for measuring them, and their relation to the bidirectional transmittance distribution function (BTDF) is discussed.

5.
Prog Urol ; 30(15): 964-969, 2020 Nov.
Artigo em Francês | MEDLINE | ID: mdl-33008717

RESUMO

INTRODUCTION: The purpose of this article is to explain the role of urology nurse in prehabilitation and same-day discharge programs for robotic radical prostatectomy. METHODS: This article is based on the analysis of the literature and the experience of our center. RESULTS: In order to prepare patients for outpatient surgery, urology nurse plays a key role during prehabilitation journeys. Two weeks before the operation, the healthcare teams (nurses, anesthetists, physiotherapists, etc.) organize workshops to explain to patients the operation course and post-operative care in order to allay any anxieties. Individual and group interviews, in specific workshops (compression stockings, urinary catheter, sexology) are organized in particular with urology nurse to answer all patients' questions. In association with enhanced recovery after surgery pathway, these programs improve the patient experience and satisfaction as well as peri-operative outcomes, and allows the development of an outpatient surgery program which currently represents approximately one third of surgeries. CONCLUSION: The implementation of perioperative protocols including prehabilitation improves the early results of robotic total prostatectomy, but also the patient experience. The urology nurse has a key role to play during these patient education days and in the preparation, information, support and follow-up of the patient, since the prehabilitation journey until the patient leaves the outpatient clinic.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Enfermagem em Nefrologia , Papel do Profissional de Enfermagem , Alta do Paciente , Exercício Pré-Operatório , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos , Procedimentos Cirúrgicos Ambulatórios/enfermagem , Humanos
6.
Extremophiles ; 24(2): 219-225, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31732815

RESUMO

We surveyed the diversity of cultivable fungi isolated from cold and hot volcanic soils of Deception Island, Antarctica. Seventy-four fungal isolates were identified; these belonged to 17 taxa in the genera Aspergillus, Penicillium, Pseudogymnoascus, Purpureocillium, and Mortierella. The fungal assemblages showed low diversity, richness, and dominance indices. The Aspergillus taxa were dominant in the soils at 0 °C, 50 °C, and 100 °C. Aspergillus lacticoffeatus, Aspergillus cf. ruber, Penicillium citrinun, and Purpureocillium sodanum were present only in soils having a temperature of 100 °C. Aspergillus calidoustus was present in all thermal soils and displayed the highest densities. The majority of fungi displayed mesophilic behavior; however, different isolates of Aspergillus lacticoffeatus and Aspergillus niger were able to grow at 50 °C; these are phylogenetically close to the causative agents of aspergillosis in immunocompromised individuals. Deception Island perhaps represents one of the most visited regions in Antarctica and the tourism there has increased over the last 20 years, especially by elderly tourists, probably with weak immune systems, come in contact with the resident microorganisms, including the thermo-resistant opportunistic Aspergillus species.


Assuntos
Solo , Idoso , Regiões Antárticas , Ascomicetos , Fungos , Humanos , Ilhas , Microbiologia do Solo
7.
Biomed Opt Express ; 10(5): 2478-2492, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31149380

RESUMO

Gliomas are diffuse and hard to cure brain tumors. A major reason for their aggressive behavior is their property to infiltrate the brain. The gross appearance of the infiltrative component is comparable to normal brain, constituting an obstacle to extended surgical resection. 5-ALA induced PpIX fluorescence measurements enable gains in sensitivity to detect infiltrated cells, but still lack sensitivity to get accurate discrimination between the tumor margin and healthy tissue. In this fluorescence spectroscopic study, we assume that two states of PpIX contribute to total fluorescence to get better discrimination of healthy tissues against tumor margins. We reveal that fluorescence in low-density margins of high-grade gliomas or in low-grade gliomas is mainly influenced by the second state of PpIX centered at 620 nm. We thus conclude that consideration of the contributions of both states to total fluorescence can help to improve fluorescence-guided resection of gliomas by discriminating healthy tissues from tumor margins.

8.
Clin Infect Dis ; 68(8): 1320-1326, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30107568

RESUMO

BACKGROUND: Pneumocystis pneumonia (PCP) is associated with morbidity and mortality in solid organ transplant (SOT) recipients. In this case-control study, we determined the association between posttransplant PCP and 3 variables: cytomegalovirus (CMV) infection, allograft rejection, and prophylaxis. METHODS: Eight transplant centers participated. For each case (SOT recipient with PCP), 3-5 controls (SOT recipients without PCP) were included. Controls were matched to the cases based on transplant center, type of allograft, and date of transplantation (±6 months). RESULTS: We enrolled 53 cases and 209 controls. Transplant types included kidney (n = 198), heart (n = 30), liver (n = 15), kidney-pancreas (n = 14), and lung (n = 5). PCP occurred beyond 12 months after transplantation in 43 (81.1%) cases. Thirty-four cases (64.1%) required admission to the intensive care unit, and 28 (52.8%) had mechanical ventilation. Allograft failure occurred in 20 (37.7%) cases, and 14 (26.9%) died. No patient developed PCP prophylaxis breakthrough. The proportion of female sex (P = .009), kidney dysfunction (P = .001), cardiac diseases (P = .005), diabetes mellitus (P = .03), allograft rejection (P = .001), CMV infection (P = .001), and severe lymphopenia (P = .001) were significantly higher in cases. In the logistic regression model, CMV infection (adjusted odds ratio [aOR], 4.6 [95% confidence interval {CI}, 2.0-10.5]) and allograft rejection (aOR, 3.0 [95% CI, 1.5-6.1]) significantly increased the likelihood of PCP. CONCLUSIONS: PCP was mostly a late-onset disease occurring after complete course of prophylaxis, particularly among patients with CMV infection or allograft rejection. PCP is associated with significant allograft loss. Extended prophylaxis targeting recipients with allograft rejection or CMV infection may reduce the risk of PCP.


Assuntos
Infecções por Citomegalovirus/imunologia , Rejeição de Enxerto/imunologia , Pneumonia por Pneumocystis/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Transplantados , Transplante Homólogo
9.
Encephale ; 44(6): 517-522, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29960683

RESUMO

INTRODUCTION: In recent years, the integration of resilience in several psychological and medical studies underscores a need for resilience assessment measures with robust psychometric properties. This study aimed to evaluate the underlying structure of the French version of the Resilience Scale (RS-14), a widely used measure to assess resilience both in general and clinical population. METHOD: A sample of 2195 college students from France (18.68% of male; Mean age=20.09 years old (±1.21) completed the RS-14, the Child and Youth Resilience Measure, the Social Support Questionnaire and the Kessler Psychological Distress Scale. EFA with parallel analysis was conducted to assess the factorial structure of the RS-14 while CFA was performed to investigate the goodness-of-fit. Internal consistency, concurrent and convergent validity were evaluated. RESULTS: A one-dimensional-factorial-solution emerged from the EFA, its goodness-of-fit was adequate and it presented good internal consistency. As expected, the RS-14 score correlated positively to the CYRM and SSQ scores and negatively to the psychological distress score, supporting the validity of the scale. CONCLUSION: The one-dimensional-factor corroborates the initial and many languages versions of the RS-14. The results showed that the French version of the RS-14 presents adequate psychometric properties and that is a reliable and valid scale in evaluating resilience.


Assuntos
Testes Neuropsicológicos , Psicometria , Resiliência Psicológica , Análise Fatorial , Feminino , França , Humanos , Masculino , Reprodutibilidade dos Testes , Apoio Social , Estresse Psicológico/diagnóstico , Estresse Psicológico/psicologia , Estudantes , Traduções , Universidades , Adulto Jovem
10.
Int J Cosmet Sci ; 40(1): 75-80, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29057486

RESUMO

OBJECTIVE: The colour of a nail polish varies according to the nail on which it is applied. The objective of this study was to predict the colour of the nail polish on a given nail and to study how the colour varies depending on the nail polish thickness. METHODS: Six nail polishes were applied in one, two and three layers on the nails of one subject, thus forming eighteen samples. The spectral reflectances of the eighteen nail polishes applied on the nails with different thicknesses were obtained by spectrophotometry. The spectral reflectances of the nails without polish were also measured using the same technique. The thicknesses of nail polishes were measured by high-definition optical coherence tomography (HD-OCT). Then, to determine the physical parameters of the nail polish itself, we applied the six nail polishes on an opacity drawdown chart and we measured the spectral reflectance and the thickness of each patch using spectrophotometry and HD-OCT, respectively. The Kubelka-Munk theory was used to get the predicted spectral reflectance of the nail polish applied on the nail according to the polish thickness by knowing the parameter of the polish itself and the spectral reflectance of the nail. The predicted spectral reflectances were finally compared with those measured directly on the nails. RESULTS: The predicted spectral reflectances were rather close to measured ones. Consequently, knowing the colour of the nail without polish and the optical parameters of the nail polish itself, we can estimate the colour of the nail polish applied on the nail depending on its thickness. CONCLUSION: Our study showed that the Kubelka-Munk theory can be used to predict the nail polish colour. The ability to predict the real colour of a nail polish applied on a nail could help a nail polish manufacturer to improve his polish formulae in order to obtain a precise colour.


Assuntos
Cor , Cosméticos , Unhas , Humanos , Espectrofotometria/métodos
12.
Sci Rep ; 7(1): 7446, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28785027

RESUMO

Recent models propose deoxyribonucleic acid methylation of key neuro-regulatory genes as a molecular mechanism underlying the increased risk of mental disorder associated with early life adversity (ELA). The goal of this study was to examine the association of ELA with oxytocin receptor gene (OXTR) methylation among young adults. Drawing from a 21-year longitudinal cohort, we compared adulthood OXTR methylation frequency of 46 adults (23 males and 23 females) selected for high or low ELA exposure based on childhood socioeconomic status and exposure to physical and sexual abuse during childhood and adolescence. Associations between OXTR methylation and teacher-rated childhood trajectories of anxiousness were also assessed. ELA exposure was associated with one significant CpG site in the first intron among females, but not among males. Similarly, childhood trajectories of anxiousness were related to one significant CpG site within the promoter region among females, but not among males. This study suggests that females might be more sensitive to the impact of ELA on OXTR methylation than males.


Assuntos
Experiências Adversas da Infância , Ansiedade/genética , Metilação de DNA , Receptores de Ocitocina/genética , Estresse Psicológico/genética , Adolescente , Adulto , Criança , Ilhas de CpG , Epigênese Genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Íntrons , Estudos Longitudinais , Masculino , Estudos Prospectivos , Análise de Sequência de DNA , Fatores Sexuais , Adulto Jovem
13.
Transplant Proc ; 48(6): 1993-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27569934

RESUMO

BACKGROUND: The impact of renal function recovery on graft survival was examined using estimated glomerular filtration rate (eGFR) slope after kidney transplantation (GAP classification); this was compared to the conventional classification of immediate graft function (IGF), slow graft function (SGF), and delayed graft function (DGF). MATERIALS AND METHODS: Overall, 541 cases of cadaveric renal transplants were reviewed from a prospective transplant database. eGFR and its slope were measured using the harmonic mean over the first week post-transplantation. Next, 495 kidney transplant recipients from an independent institution were assessed to determine the prognostic value of graft function based on the eGFR slope. RESULTS: The main discrimination of eGFR slopes occurred within the first 7 days. Three groups in the GAP classification (Good graft function, Average graft function, Poor graft function) were defined based on eGFR slope tertiles: good graft function (GGF), average graft function (AGF), and poor graft function (PGF) were defined based on the ΔCrCL per day over the first 7 days: <1 mL/min, 1-4 mL/min, and >4 mL/min, respectively. When applied to the validation cohort, the 5-year graft failure was 20% for the PGF group, 4% for the AGF group, and 3% for the GGF group. Multivariable Cox regression analysis demonstrated better prediction of long-term graft function with the new classification (C statistic 0.49 [old)] vs 0.61 [new]). CONCLUSION: The new GAP criteria were better at predicting long-term graft survival and renal function compared to the conventional classification system, and deserve further consideration in future studies.


Assuntos
Função Retardada do Enxerto/classificação , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Transplante de Rim , Rim/fisiopatologia , Recuperação de Função Fisiológica , Adulto , Idoso , Estudos de Coortes , Função Retardada do Enxerto/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Fatores de Tempo
14.
Pharmacogenomics J ; 16(4): 303-4, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27168097

RESUMO

Clinical applications of prenatal genetic screening currently focus on detection of aneuploidy and other genetic diseases in the developing fetus. Growing evidence suggests that the fetal genome may also be informative about fetal exposures through contributions to placental transport as well as placental and fetal metabolism. Possible clinical applications of prenatal pharmacogenomic screening include prospective optimization of medication selection and dosage, as well as retrospective assessment of whether a fetus was previously exposed to significant risk. Newly available noninvasive methods of prenatal genetic screening mean that relevant fetal genotypes could be made available to obstetricians for use in management of a current pregnancy. This promising area for research merits more attention than it has thus far received.The Pharmacogenomics Journal advance online publication, 10 May 2016; doi:10.1038/tpj.2016.33.


Assuntos
Pesquisa Biomédica/métodos , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Membrana Transportadoras/genética , Farmacogenética/métodos , Testes Farmacogenômicos , Variantes Farmacogenômicos , Diagnóstico Pré-Natal/métodos , Animais , Biotransformação , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Feto/metabolismo , Genótipo , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Fenótipo , Placenta/metabolismo , Gravidez
15.
Am J Transplant ; 16(12): 3416-3429, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27172087

RESUMO

Pretransplant autoantibodies to LG3 and angiotensin II type 1 receptors (AT1R) are associated with acute rejection in kidney transplant recipients, whereas antivimentin autoantibodies participate in heart transplant rejection. Ischemia-reperfusion injury (IRI) can modify self-antigenic targets. We hypothesized that ischemia-reperfusion creates permissive conditions for autoantibodies to interact with their antigenic targets and leads to enhanced renal damage and dysfunction. In 172 kidney transplant recipients, we found that pretransplant anti-LG3 antibodies were associated with an increased risk of delayed graft function (DGF). Pretransplant anti-LG3 antibodies are inversely associated with graft function at 1 year after transplantation in patients who experienced DGF, independent of rejection. Pretransplant anti-AT1R and antivimentin were not associated with DGF or its functional outcome. In a model of renal IRI in mice, passive transfer of anti-LG3 IgG led to enhanced dysfunction and microvascular injury compared with passive transfer with control IgG. Passive transfer of anti-LG3 antibodies also favored intrarenal microvascular complement activation, microvascular rarefaction and fibrosis after IRI. Our results suggest that anti-LG3 antibodies are novel aggravating factors for renal IRI. These results provide novel insights into the pathways that modulate the severity of renal injury at the time of transplantation and their impact on long-term outcomes.


Assuntos
Autoanticorpos/sangue , Função Retardada do Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Proteoglicanas de Heparan Sulfato/imunologia , Transplante de Rim/efeitos adversos , Traumatismo por Reperfusão/etiologia , Animais , Autoanticorpos/imunologia , Função Retardada do Enxerto/sangue , Função Retardada do Enxerto/patologia , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Falência Renal Crônica/cirurgia , Testes de Função Renal , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Prognóstico , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/patologia , Estudos Retrospectivos , Fatores de Risco
16.
Clin Pharmacol Ther ; 100(1): 53-62, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27082931

RESUMO

The pharmacokinetics of many drugs are altered by pregnancy. Drug distribution and protein binding are changed by pregnancy. While some drug metabolizing enzymes have an apparent increase in activity, others have an apparent decrease in activity. Not only is drug metabolism affected by pregnancy, but renal filtration is also increased. In addition, pregnancy alters the apparent activities of multiple drug transporters resulting in changes in the net renal secretion of drugs.


Assuntos
Preparações Farmacêuticas/metabolismo , Farmacocinética , Gravidez/metabolismo , Feminino , Humanos , Rim/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Preparações Farmacêuticas/administração & dosagem , Ligação Proteica , Distribuição Tecidual
17.
Appl Opt ; 55(1): 27-37, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26835617

RESUMO

The four-flux model is a method to solve light radiative-transfer problems in planar, possibly multilayer structures. The light fluxes are modeled as two collimated and two diffuse beams propagating forward and backward perpendicularly to the layer stack. In the present contribution, we develop a four-flux model relying on a matrix formalism to determine the reflectance and transmittance factors of stacks of components by knowing those of each individual component. This model is also extended to generate the bidirectional scattering distribution function of the stack by considering an incoming collimated flux in any direction and by taking into account the directionality of the diffuse fluxes exiting from the material at the border components of the stack. The model is applied to opaque Lambertian backgrounds with flat or rough interfaces for which analytical expressions of the BSDF are obtained.

18.
Rev Neurol (Paris) ; 172(3): 186-97, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26626577

RESUMO

The only acute treatment of ischemic stroke approved by the health authorities is tissue recombinant plasminogen activator (tPA)-induced thrombolysis. Under physiological conditions, tPA, belonging to the serine protease family, is secreted by endothelial and brain cells (neurons, astrocytes, microglia, oligodendrocytes). Although revascularisation induced by tPA is beneficial during a stroke, research over the past 20 years shows that tPA can also be deleterious for the brain parenchyma. Thus, in this review of the literature, after a brief history on the discovery of tPA, we reviewed current knowledge of mechanisms by which tPA can influence brain function in physiological and pathological conditions.


Assuntos
Ativador de Plasminogênio Tecidual/genética , Animais , Química Encefálica/genética , Humanos , Serina Proteases/genética , Serina Proteases/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo
19.
Am J Transplant ; 15(5): 1205-18, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25808553

RESUMO

Transplant vasculopathy is associated with neointimal accumulation of recipient-derived mesenchymal stem cells. Increased circulating levels of LG3, a C-terminal fragment of perlecan, were found in renal transplant patients with vascular rejection. Here, we evaluated whether LG3 regulates the migration and homing of mesenchymal stem cells and the accumulation of recipient-derived neointimal cells. Mice were transplanted with a fully-MHC mismatched aortic graft followed by intravenous injection of recombinant LG3. LG3 injections increased neointimal accumulation of α-smooth muscle actin positive cells. When green fluorescent protein (GFP)-transgenic mice were used as recipients, LG3 injection favored accumulation of GFP+ cells to sites of neointima formation. LG3 increased horizontal migration and transmigration of mouse and human MSC in vitro and led to increased ERK1/2 phosphorylation. Neutralizing ß1 integrin antibodies or use of mesenchymal stem cells from α2 integrin-/- mice decreased migration in response to recombinant LG3. Reduced intima-media ratios and decreased numbers of neointimal cells showing ERK1/2 phosphorylation were found in α2-/- recipients injected with recombinant LG3. Collectively, our results suggest that LG3, through interactions with α2ß1 integrins on recipient-derived cells leading to activation of ERK1/2 and increased migration, favors myointimal thickening.


Assuntos
Rejeição de Enxerto/patologia , Proteoglicanas de Heparan Sulfato/química , Integrina alfa2beta1/metabolismo , Células-Tronco Mesenquimais/citologia , Neointima/patologia , Enxerto Vascular , Animais , Aorta/patologia , Aorta/transplante , Prótese Vascular , Espessura Intima-Media Carotídea , Movimento Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Integrina beta1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Miócitos de Músculo Liso/citologia , Fenótipo , Estrutura Terciária de Proteína , Ratos , Proteínas Recombinantes/metabolismo
20.
Extremophiles ; 19(3): 585-96, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25809294

RESUMO

We surveyed the diversity and capability of producing bioactive compounds from a cultivable fungal community isolated from oligotrophic soil of continental Antarctica. A total of 115 fungal isolates were obtained and identified in 11 taxa of Aspergillus, Debaryomyces, Cladosporium, Pseudogymnoascus, Penicillium and Hypocreales. The fungal community showed low diversity and richness, and high dominance indices. The extracts of Aspergillus sydowii, Penicillium allii-sativi, Penicillium brevicompactum, Penicillium chrysogenum and Penicillium rubens possess antiviral, antibacterial, antifungal, antitumoral, herbicidal and antiprotozoal activities. Bioactive extracts were examined using (1)H NMR spectroscopy and detected the presence of secondary metabolites with chemical shifts. Our results show that the fungi present in cold-oligotrophic soil from Antarctica included few dominant species, which may have important implications for understanding eukaryotic survival in cold-arid oligotrophic soils. We hypothesize that detailed further investigations may provide a greater understanding of the evolution of Antarctic fungi and their relationships with other organisms described in that region. Additionally, different wild pristine bioactive fungal isolates found in continental Antarctic soil may represent a unique source to discover prototype molecules for use in drug and biopesticide discovery studies.


Assuntos
Bioprospecção , Frio Extremo , Fungos/isolamento & purificação , Microbiota , Microbiologia do Solo , Aedes/efeitos dos fármacos , Animais , Regiões Antárticas , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/toxicidade , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/toxicidade , Citotoxinas/isolamento & purificação , Citotoxinas/toxicidade , Fungos/química , Fungos/classificação , Humanos , Inseticidas/isolamento & purificação , Inseticidas/toxicidade , Lactuca/efeitos dos fármacos , Células MCF-7
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