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1.
J Neurovirol ; 23(4): 615-620, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28439773

RESUMO

Hepatitis E virus (HEV) infection is an emerging autochthonous disease in industrialized countries. Extra-hepatic manifestations, in particular neurologic manifestations, have been reported in HEV infection. Only a few cases of hepatitis E-associated Parsonage-Turner syndrome have been reported, and HEV genotypes were rarely determined. Here, we report the case of a Parsonage-Turner syndrome associated with an acute autochthonous HEV infection in a 55-year-old immunocompetent patient. HEV genomic RNA was detected in serum and cerebrospinal fluid samples (CSF), and molecular phylogenetic analysis of HEV was performed. The interest of this case lies in its detailed description notably the molecular analysis of HEV RNA isolated from serum and CSF. HEV infection should be considered in diagnostic investigations of neurologic manifestations associated with liver function perturbations.


Assuntos
Neurite do Plexo Braquial/diagnóstico , Genótipo , Vírus da Hepatite E/genética , Hepatite E/diagnóstico , RNA Viral , Doença Aguda , Neurite do Plexo Braquial/etiologia , Neurite do Plexo Braquial/patologia , Neurite do Plexo Braquial/virologia , Hepatite E/complicações , Hepatite E/patologia , Hepatite E/virologia , Vírus da Hepatite E/classificação , Vírus da Hepatite E/isolamento & purificação , Humanos , Imunocompetência , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Viral/sangue , RNA Viral/líquido cefalorraquidiano
2.
Scand J Immunol ; 86(3): 143-155, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28671713

RESUMO

The complement and neutrophil defence systems, as major components of innate immunity, are activated during inflammation and infection. For neutrophil migration to the inflamed region, we hypothesized that the complement activation product C5a induces significant changes in cellular morphology before chemotaxis. Exposure of human neutrophils to C5a dose- and time-dependently resulted in a rapid C5a receptor-1 (C5aR1)-dependent shape change, indicated by enhanced flow cytometric forward-scatter area values. Similar changes were observed after incubation with zymosan-activated serum and in blood neutrophils during murine sepsis, but not in mice lacking the C5aR1. In human neutrophils, Amnis high-resolution digital imaging revealed a C5a-induced decrease in circularity and increase in the cellular length/width ratio. Biomechanically, microfluidic optical stretching experiments indicated significantly increased neutrophil deformability early after C5a stimulation. The C5a-induced shape changes were inhibited by pharmacological blockade of either the Cl-/HCO3--exchanger or the Cl- -channel. Furthermore, actin polymerization assays revealed that C5a exposure resulted in a significant polarization of the neutrophils. The functional polarization process triggered by ATP-P2X/Y-purinoceptor interaction was also involved in the C5a-induced shape changes, because pretreatment with suramin blocked not only the shape changes but also the subsequent C5a-dependent chemotactic activity. In conclusion, the data suggest that the anaphylatoxin C5a regulates basic neutrophil cell processes by increasing the membrane elasticity and cell size as a consequence of actin-cytoskeleton polymerization and reorganization, transforming the neutrophil into a migratory cell able to invade the inflammatory site and subsequently clear pathogens and molecular debris.


Assuntos
Citoesqueleto de Actina/imunologia , Forma Celular/imunologia , Complemento C5a/metabolismo , Inflamação/imunologia , Neutrófilos/imunologia , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Células Cultivadas , Quimiotaxia , Antiportadores de Cloreto-Bicarbonato/metabolismo , Complemento C5a/imunologia , Humanos , Ativação de Neutrófilo , Neutrófilos/patologia , Receptor da Anafilatoxina C5a/metabolismo , Receptores Purinérgicos P2X/metabolismo , Transdução de Sinais
3.
Neurosurg Rev ; 39(1): 133-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26621678

RESUMO

After performing a decompressive craniectomy, a cranioplastic surgery is usually warranted. The complications of this reconstructive procedure may differ from the initial operation. The authors of this study report on their experience to define patient-specific and procedural risk factors for possible complications following cranioplasty influencing the outcome (Glasgow Outcome Scale (GOS)), mobility, shunt dependency, and seizures. A retrospective analysis of 263 patients of all ages and both sexes who had undergone cranioplasty after craniectomy for traumatic brain injury (including chronic subdural hematoma), subarachnoidal hemorrhage (including intracerebral hemorrhage), ischemic stroke, and tumor surgery in one single center in 12 years from January 2000 to March 2012 has been carried out. A multiple logistic regression analysis was performed to identify potential risk factors (age, gender, used cranioplasty material, initial diagnosis, clipped or coil-embolized subarachnoidal hemorrhage (SAH) patients, time interval, complications especially hydrocephalus and seizures, mobility) upon the prognosis described as a dichotomized Glasgow Outcome Scale. Two hundred forty-eight patients met the study criteria. The overall complication rate after cranioplastic surgery was 18.5% (46 patients). Complications included: surgical site infection, epidural hematoma, hydrocephalus with or without former SAH, and new-onset seizures. Logistic regression analysis identified significant correlation between a low GOS (2 or 3) and postoperative seizures (OR 2.37, CI 1.35-4.18, p < 0.05), shunt-depending hydrocephalus (OR 5.83, CI 3.06-11.11, p < 0.05), and age between 51 and 70 years (OR 2.4, 95% CI 1.09-5.29, p = 0.029). However, gender, time interval between craniectomy and cranioplasty, initial diagnosis, and used cranioplasty material had no significant influence on post-cranioplasty complications as surgical site infections, hematoma, wound healing disturbance, seizures, or hydrocephalus. Evaluation of treatment modality in aneurysmal SAH clip vs. coil showed no significant relation to postoperative complications either. Complications after cranioplastic surgery are a common problem, as prognostic factors could identify a shunt-depending hydrocephalus and epilepsia to develop a major deficit after cranioplastic surgery (GOS 2 or 3). We detected a significant extra risk of people between the age of 51 and 70 years to end up in GOS level 2 or 3.


Assuntos
Craniectomia Descompressiva/métodos , Procedimentos Neurocirúrgicos/métodos , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/cirurgia , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Epilepsia/etiologia , Epilepsia/cirurgia , Feminino , Escala de Resultado de Glasgow , Humanos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Lactente , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Convulsões/etiologia , Acidente Vascular Cerebral/cirurgia , Hemorragia Subaracnóidea/cirurgia , Adulto Jovem
4.
Infect Immun ; 83(6): 2338-49, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25824835

RESUMO

In this study, the cytotoxicity of the recently described subtilase variant SubAB2-2 of Shiga toxin-producing Escherichia coli was determined and compared to the plasmid-encoded SubAB1 and the chromosome-encoded SubAB2-1 variant. The genes for the respective enzymatic active (A) subunits and binding (B) subunits of the subtilase toxins were amplified and cloned. The recombinant toxin subunits were expressed and purified. Their cytotoxicity on Vero cells was measured for the single A and B subunits, as well as for mixtures of both, to analyze whether hybrids with toxic activity can be identified. The results demonstrated that all three SubAB variants are toxic for Vero cells. However, the values for the 50% cytotoxic dose (CD50) differ for the individual variants. Highest cytotoxicity was shown for SubAB1. Moreover, hybrids of subunits from different subtilase toxins can be obtained which cause substantial cytotoxicity to Vero cells after mixing the A and B subunits prior to application to the cells, which is characteristic for binary toxins. Furthermore, higher concentrations of the enzymatic subunit SubA1 exhibited cytotoxic effects in the absence of the respective B1 subunit. A more detailed investigation in the human HeLa cell line revealed that SubA1 alone induced apoptosis, while the B1 subunit alone did not induce cell death.


Assuntos
Proteínas de Escherichia coli/metabolismo , Proteínas Recombinantes/metabolismo , Escherichia coli Shiga Toxigênica/enzimologia , Subtilisinas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Chlorocebus aethiops , Clonagem Molecular , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Variação Genética , Células HeLa , Humanos , Subunidades Proteicas , Proteínas Recombinantes/genética , Escherichia coli Shiga Toxigênica/genética , Subtilisinas/genética , Células Vero
5.
Arch Toxicol ; 89(10): 1881-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26314262

RESUMO

The paper describes the importance of toxicology as a discipline, its past achievements, current scientific challenges, and future development. Toxicological expertise is instrumental in the reduction of human health risks arising from chemicals and drugs. Toxicological assessment is needed to evaluate evidence and arguments, whether or not there is a scientific base for concern. The immense success already achieved by toxicological work is exemplified by reduced pollution of air, soil, water, and safer working places. Predominantly predictive toxicological testing is derived from the findings to assess risks to humans and the environment. Assessment of the adversity of molecular effects (including epigenetic effects), the effects of mixtures, and integration of exposure and biokinetics into in vitro testing are emerging challenges for toxicology. Toxicology is a translational science with its base in fundamental science. Academic institutions play an essential part by providing scientific innovation and education of young scientists.


Assuntos
Medição de Risco/métodos , Testes de Toxicidade/métodos , Toxicologia/organização & administração , Animais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Poluentes Ambientais/toxicidade , Alemanha , Humanos , Sociedades Científicas , Toxicologia/métodos
6.
J Clin Microbiol ; 51(9): 3039-46, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23850954

RESUMO

Respiratory viruses are the leading cause of acute infections in humans. However, the burden of certain respiratory viruses, such as coronaviruses, and the relevance of viral coinfections remain unclear. In this study, we investigated the distribution and seasonal occurrences of respiratory viruses detected by multiplex molecular assay in 6,014 samples from 2008 to 2011 in a French hospital. We assessed the detection frequencies of 14 respiratory viruses and their clinical impact in immunosuppressed and nonimmunosuppressed patients. Furthermore, we explored the preferential association patterns between respiratory viruses in multiple infections. Our results indicated that human rhinovirus/enterovirus (HRV/EV) and coronavirus (HCoV) were frequently detected in respiratory samples (48.81% and 11.74% of infected samples, respectively), and the detection frequencies of these viruses were further increased in immunosuppressed patients. The most common subtypes of HCoV were HCoV-229E (33.80%) and HCoV-HKU1 (32.39%). A sharp increase in the detection frequencies of HCoV-229E and HCoV-HKU1 over several months suggested that these subtypes were epidemic in our population. In immunosuppressed patients, HCoV contributed to upper respiratory tract infections (52%). Evidence did not support lower respiratory tract infections exclusive to a unique HCoV infection. In multiply infected individuals, determined in 6.3% of samples, HRV/EV and HCoV were detected in 33.29% and 22.90% of samples, respectively. Interestingly, nearly 50% of HCoV infections were detected in association with another virus. Since the distributions of respiratory viruses in multiply infected patients were subject to preferential association patterns between viruses, we propose complex interactions between different respiratory viruses and host factors.


Assuntos
Coinfecção/epidemiologia , Coinfecção/virologia , Infecções por Coronavirus/epidemiologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Vírus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecções por Coronavirus/virologia , Feminino , França/epidemiologia , Hospitais , Humanos , Hospedeiro Imunocomprometido , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Acta Neurochir Suppl ; 112: 93-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21691994

RESUMO

Cerebral vasospasm complicating aneurysmal subarachnoid hemorrhage is a well-known medical entity. The delayed ischemic neurological deficits (DIND) as a result of vasospasm remain the main cause of morbidity among patients who manage to survive this severe disease pattern. When the traditional treatment options, either medical or interventional, fail to reverse vasospasm, continuous intraarterial infusion of nimodipine through catheters directly into the spastic arteries presents a promising treatment modality. Of 73 patients with aneurysmal subarachnoid hemorrhage between 2008 and 2009, a total of 27 had Hunt and Hess grades of 4 and 5. Fifteen percent of them showed refractory vasospasms and were treated with continuous nimodipine infusion via catheters in both internal carotid arteries. We present the method's indications and possible complications.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Infusões Intra-Arteriais/métodos , Nimodipina/administração & dosagem , Vasoespasmo Intracraniano/tratamento farmacológico , Angiografia Cerebral , Humanos , Estudos Retrospectivos , Hemorragia Subaracnóidea/complicações , Tomografia Computadorizada por Raios X/métodos , Vasoespasmo Intracraniano/etiologia
8.
Vasa ; 40(5): 375-80, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21948780

RESUMO

BACKGROUND: Three-dimensional (3D) angiography is increasingly used in the diagnostics of brain aneurysms. Aim of the present study was to evaluate the accuracy of 3D angiograms with respect to its value for preoperative planning of aneurysm clipping. PATIENTS AND METHODS: The 3D angiograms of 42 patients with subarachnoid bleeding caused by aneurysm rupture of the anterior circle of Willis and the intradural carotid have been compared to intraoperative photographs of the aneurysms. RESULTS: Neighbouring vessels, aneurysm anatomy, arteries originating from the aneurysm wall were accurately shown decreasing the surgical risk of aneurysm clipping. CONCLUSIONS: The 3D images enabled a perfect preoperative planning through the operation by illuminating the aneurysm anatomy, neck localisation and shape and relation of the aneurysm to neighbouring vessels. Operative approach, use of an accurate clip and avoidance of clipping arteries close to the aneurysm have become predictable and safer by the use of 3D angiography.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Angiografia Cerebral/métodos , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Procedimentos Neurocirúrgicos , Hemorragia Subaracnóidea/diagnóstico por imagem , Procedimentos Cirúrgicos Vasculares , Adolescente , Adulto , Idoso , Aneurisma Roto/etiologia , Aneurisma Roto/cirurgia , Desenho de Equipamento , Alemanha , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/instrumentação , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/cirurgia , Instrumentos Cirúrgicos , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/instrumentação , Adulto Jovem
9.
J Cell Biol ; 149(2): 263-70, 2000 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-10769020

RESUMO

The ephrins, ligands of Eph receptor tyrosine kinases, have been shown to act as repulsive guidance molecules and to induce collapse of neuronal growth cones. For the first time, we show that the ephrin-A5 collapse is mediated by activation of the small GTPase Rho and its downstream effector Rho kinase. In ephrin-A5-treated retinal ganglion cell cultures, Rho was activated and Rac was downregulated. Pretreatment of ganglion cell axons with C3-transferase, a specific inhibitor of the Rho GTPase, or with Y-27632, a specific inhibitor of the Rho kinase, strongly reduced the collapse rate of retinal growth cones. These results suggest that activation of Rho and its downstream effector Rho kinase are important elements of the ephrin-A5 signal transduction pathway.


Assuntos
Axônios/fisiologia , Toxinas Botulínicas , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/fisiologia , Proteínas rho de Ligação ao GTP/metabolismo , ADP Ribose Transferases/farmacologia , Amidas/farmacologia , Animais , Axônios/efeitos dos fármacos , Axônios/ultraestrutura , Células Cultivadas , Embrião de Galinha , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Efrina-A5 , Glutationa Transferase/genética , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Piridinas/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/genética , Quinases Associadas a rho
10.
Neuron ; 24(2): 433-41, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10571236

RESUMO

Neurophysiological studies and computational models of illusory contour formation have focused on contour orientation as the underlying determinant of illusory contour shape in both static and moving displays. Here, we report a class of motion-induced illusory contours that demonstrate the existence of novel mechanisms of illusory contour synthesis. In a series of experiments, we show that the velocity of contour terminations and the direction of motion of a partially occluded figure regulate the perceived shape and apparent movement of illusory contours formed from moving image sequences. These results demonstrate the existence of neural mechanisms that reconstruct occlusion relationships from both real and inferred image velocities, in contrast to the static geometric mechanisms that have been the focus of studies to date.


Assuntos
Percepção de Forma/fisiologia , Ilusões/fisiologia , Percepção de Movimento/fisiologia , Encéfalo/fisiologia , Humanos , Modelos Neurológicos
11.
Acta Neurochir (Wien) ; 150(4): 391-4; discussion 394, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18297230

RESUMO

We report a patient who suffered drop attacks during head reclination. Computer tomography of the cervical spine demonstrated a stenotic right vertebral artery at C4/5. However, Doppler ultrasonography of the vertebral artery showed no abnormality. Angiography confirmed complete occlusion of the left vertebral and a stenosis of the right vertebral artery. Dynamic angiography indicated occlusion of the stenotic region on the right side during reclination of the head. Surgery using a posterior approach with decompression of the vertebral artery, lead to an excellent outcome and the patient left the hospital without any symptoms. Therefore, in patients with drop attacks and normal ultrasonography, a stenosis of the vertebral artery caused by a spondylophytic compression could still be the cause. At worst, the stenosis could lead to brain infarction if left untreated. Dynamic angiography is crucial for the diagnosis and surgical decompression has excellent results.


Assuntos
Vértebras Cervicais/cirurgia , Descompressão Cirúrgica/métodos , Espondilite Anquilosante/cirurgia , Insuficiência Vertebrobasilar/cirurgia , Idoso , Angiografia , Vértebras Cervicais/diagnóstico por imagem , Movimentos da Cabeça/fisiologia , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Reoperação , Compressão da Medula Espinal/cirurgia , Fusão Vertebral , Espondilite Anquilosante/diagnóstico por imagem , Síncope/diagnóstico por imagem , Síncope/etiologia , Síncope/cirurgia , Tomografia Computadorizada por Raios X , Insuficiência Vertebrobasilar/diagnóstico por imagem
13.
Sci Rep ; 7(1): 11870, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28928400

RESUMO

Surface colonization by microorganisms leads to the formation of biofilms, i.e. aggregates of bacteria embedded within a matrix of extracellular polymeric substance. This promotes adhesion to the surface and protects bacterial community, providing an antimicrobial-resistant environment. The inhibition of biofilm growth is a crucial issue for preventing bacterial infections. Inorganic nanoparticle/Teflon-like (CFx) composites deposited via ion beam sputtering demonstrated very efficient antimicrobial activity. In this study, we developed Ag-CFx thin films with tuneable metal loadings and exceptional in-plane morphological and chemical homogeneity. Ag-CFx antimicrobial activity was studied via mid-infrared attenuated total reflection spectroscopy utilizing specifically adapted multi-reflection waveguides. Biofilm was sampled by carefully depositing the Ag-CFx film on IR inactive regions of the waveguide. Real-time infrared spectroscopy was used to monitor Pseudomonas fluorescens biofilm growth inhibition induced by the bioactive silver ions released from the nanoantimicrobial coating. Few hours of Ag-CFx action were sufficient to affect significantly biofilm growth. These findings were corroborated by atomic force microscopy (AFM) studies on living bacteria exposed to the same nanoantimicrobial. Morphological analyses showed a severe bacterial stress, leading to membrane leakage/collapse or to extended cell lysis as a function of incubation time.


Assuntos
Antibacterianos , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Politetrafluoretileno , Pseudomonas fluorescens/fisiologia , Prata , Antibacterianos/química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Politetrafluoretileno/química , Politetrafluoretileno/farmacologia , Prata/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Rev Physiol Biochem Pharmacol ; 152: 165-82, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15368096

RESUMO

The focus of this article is on the cellular uptake mechanism of the family of binary actin ADP-ribosylating toxins from clostridia. These toxins are special-type AB toxins, because they are composed of two nonlinked proteins, which have to assemble on the surface of eukaryotic cells to act cytotoxically. The enzymatically active component (A), ADP-ribosylates G-actin in the cytosol of target cells. This leads to a complete depolymerization of the actin filaments and, thereby, to rounding up of cultured cells. The second component of these toxins, the binding/translocation component (B), mediates the transport of the enzyme component into the cytosol.


Assuntos
Actinas/metabolismo , Adenosina Difosfato Ribose/metabolismo , Toxinas Bacterianas/metabolismo
15.
J Natl Cancer Inst ; 64(6): 1345-8, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6929372

RESUMO

Tumor extracts varying in carcinoembryonic antigen (CEA) content (0.4--2,280 ng/mg protein) did not affect the reactivity of cancer patients' leukocytes in the leukocyte migration inhibition test (LMIT). In addition, variations in the plasma CEA levels of tumor-bearing leukocyte donors did not influence the frequency of significant LMIT reactivity.


Assuntos
Antígeno Carcinoembrionário/análise , Inibição de Migração Celular , Neoplasias/imunologia , Adenocarcinoma/imunologia , Carcinoma/imunologia , Carcinoma de Células Escamosas/imunologia , Neoplasias do Colo/imunologia , Feto/imunologia , Humanos , Leucócitos/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Gástricas/imunologia
16.
Cancer Res ; 56(10): 2268-72, 1996 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8625296

RESUMO

The mechanism of the transient G2 arrest induced by small doses of ionizing radiation involves the failure to activate the correctly formed pre-mitosis-promoting factor (MPF) complex of cyclin B and p34cdc2 by dephosphorylation at Tyr15 of the latter, as recent studies of other laboratories have indicated. Similar data were obtained with the G2 arrest-inducing agents epidermal growth factor and the phorbol ester 12-0- tetradecanoylphorbol-13-acetate (H. Barth and V. Kinzel, Exp. Cell Res., 212: 383-388, 1994, and H. Barth and V. Kinzel, J. Cell. Physiol., 162: 44-51, 1995). To differentiate the radiation consequences in synchronized HeLa cells from those of 12-0-tetradecanoylphorbol-13-acetate and epidermal growth factor, experiments with a very small dose (1 Gy) have been carried out in cells close to the G2-M border and, for comparison, in mitotic cells. We show that in addition to the failure of p34cdc2 dephosphorylation at Tyr15, radiation with 1 Gy also prevents the activation of the phosphatase cdc25-C, the enzyme catalyzing the MPF activation. In contrast, irradiation of mitotic cells with 1 Gy did not influence that fraction of either MPF or cdc25-C already activated. Moreover, the gain in MPM-2 antigenicity of cdc25-C, usually indicative of an activating phosphorylation, is shown to be prevented by 1 Gy. The data indicate that the initiation of the proposed autocatalytic loop between MPF and cdc25-C becomes interrupted by radiation, but they give no hint at which point.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Fase G2/efeitos da radiação , Células HeLa/efeitos da radiação , Fator Promotor de Maturação/metabolismo , Mitose/efeitos da radiação , Fosfoproteínas Fosfatases/metabolismo , Proteína Quinase CDC2/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Fase G2/genética , Células HeLa/metabolismo , Humanos , Mitose/genética , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Protamina Quinase/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fosfatases cdc25
17.
J Am Coll Cardiol ; 31(3): 487-93, 1998 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9502624

RESUMO

OBJECTIVES: This study sought to demonstrate the equivalence of saruplase and streptokinase in terms of 30-day mortality. BACKGROUND: The use of thrombolytic agents in the treatment of acute myocardial infarction is well established and has been shown to substantially reduce post-myocardial infarction mortality. METHODS: Three thousand eighty-nine patients with symptoms compatible with those of acute myocardial infarction for < 6 h entered the study at a total of 104 centers and were randomized to receive streptokinase (1.5-MU infusion over 60 min) or saruplase (20-mg bolus and 60-mg infusion over 60 min). In the saruplase group, a bolus of heparin (5,000 IU) was administered before saruplase, and a corresponding blinded double-dummy placebo bolus was administered before streptokinase. All patients received intravenous heparin infusions for > or = 24 h starting 30 min after the end of the thrombolytic infusions; the infusions were titrated to maintain an activated partial thromboplastin time at 1.5 to 2.5 times that of normal. RESULTS: Death of any cause up to 30 days after randomization occurred in 88 (5.7%) of 1,542 patients randomized to receive saruplase and 104 (6.7%) of 1,547 patients randomized to receive streptokinase (odds ratio 0.84, p < 0.01 for equivalence). Hemorrhagic strokes occurred more often in patients receiving saruplase (0.9% vs. 0.3%), whereas thromboembolic strokes were more prevalent in the streptokinase-treated patients (0.5% vs. 1.0%). The rate of bleeding was similar in the two treatment groups (10.4% vs. 10.9%). Hypotension and cardiogenic shock occurred less frequently in the saruplase group. Reinfarction rates were similar. CONCLUSIONS: Saruplase is a clinically safe and effective thrombolytic medication. This profile ranks saruplase favorably among the currently available thrombolytic agents.


Assuntos
Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Estreptoquinase/uso terapêutico , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
18.
Eur J Med Res ; 10(8): 325-31, 2005 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16131473

RESUMO

BACKGROUND: Proteolytic enzymes such as bromelain and trypsin are used as an adjuvant therapeutic approach in the treatment of chronic inflammatory, malignant and autoimmune diseases. In vitro studies have shown that proteolytic enzymes modulate surface adhesion molecules on T-cells. In this study we analysed the influence of bromelain and trypsin on the cytokine production and proliferation of peripheral blood mononuclear cells (PBMC) from patients with a classical cellular mediated autoimmune disorder, namely encephalomyelitis disseminata (ED) as well as from healthy controls. - METHODS: PBMC from patients with ED (n=12) and healthy controls (n=12) were cultured for seven days at 37 degrees C under three different conditions: without antigen, with bromelain and with trypsin (final concentrations 10-1000 microg/ml). Proliferation was determined by superset3H-thymidine incorporation. Secretion of cytokines into the supernatant was measured by a double sandwich ELISA. Intracellular cytokines were determined by flow cytometric analysis. - RESULTS: PBMC from patients with ED and healthy controls showed a significantly increased proliferative response to bromelain (ED: 14053+/- 7585 cpm with bromelain vs. spontaneous proliferation of 430+/- 255 cpm; healthy controls: 10689+/- 4607 cpm vs. 327+/-193) but not to trypsin. Bromelain induced in all 24 individuals a significant increase of the macro-phage/monocyte associated cytokines interleukin (IL)-6, granulocyte-macrophage-colony stimulating factor (GM-CSF), tumour necrosis factor alpha (TNFa) (p<0.01) as well as of the type 1 cytokine gamma-interferon (IFNgamma). In contrast, the type 2 cytokines IL-4 and IL-5 were not induced. Flow cytometric analysis revealed a significant increase of IFNgamma-producing CD4+ T-cells. There were no differences in cytokine production between ED patients and healthy controls. - CONCLUSION: These results indicate that bromelain - but not trypsin - activates macrophages/monocytes and type 1 cells independently from the underlying disease and may stimulate, therefore, the innate as well as the adaptive immune system.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bromelaínas/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Tripsina/farmacologia , Adulto , Antígenos CD/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/metabolismo , Citocinas/análise , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Encefalomielite Aguda Disseminada/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade
19.
Minerva Gastroenterol Dietol ; 51(1): 95-108, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15756149

RESUMO

Infection with hepatitis B virus (HBV) leads to a wide spectrum of clinical presentations ranging from an asymptomatic carrier state to self-limited acute or fulminant hepatitis to chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma (HCC). Infection with HBV is one of the most common viral diseases affecting man. Both viral factors as well as the host immune response have been implicated in the pathogenesis and clinical outcome of HBV infection. Evidence has been accumulating that HBV mutants are associated with certain clinical disease manifestations, may affect the natural course of the infection and confer resistance to antivirals. Naturally occurring mutations have been identified in the structural and non-structural genes as well as regulatory elements of the virus. The best characterized mutants comprise the pre-core (pre-C) stop codon mutation resulting in a loss of hepatitis B e antigen (HBeAg), defined clusters of mutations in the core promotor resulting in enhanced viral replication and mutations in the hepatitis B core and surface antigens (HBcAg and HBsAg) altering the antigenicity of the virus. More recently, several mutations in the reverse transcriptase/polymerase gene have been identified conferring resistance to antivirals used for the treatment of chronic hepatitis B. In this review, we will focus on the biological phenotype of HBV genetic variants and discuss their clinical relevance for the pathogenesis of HBV-induced liver disease.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/virologia , Antivirais/farmacologia , Códon , Farmacorresistência Viral , Genes Virais , Variação Genética , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Hepatite B/fisiopatologia , Antígenos do Núcleo do Vírus da Hepatite B/análise , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Mutação , Fenótipo , Regiões Promotoras Genéticas
20.
J Infect ; 71(1): 93-100, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25749257

RESUMO

OBJECTIVES: To determine the clinical relevance of herpes simplex virus (HSV) viremia episodes in critically ill adult patients. METHODS: 1556 blood samples obtained for HSV PCR analysis in Intensive Care Unit (ICU) patients over 4 years were retrospectively analyzed, focusing on the comprehensive analysis of 88 HSV-viremic patients. RESULTS: HSV DNA was detected in 11.8% of samples from the ICU. HSV viral loads remained below 5×10(2) copies/ml in 68.2% of patients and exceeded 10(4) copies/ml in 7.9%. Episodes of HSV-viremia correlated with immunosuppressed status and mechanical ventilation in 79.5% and 65.9% of patients, respectively. Only a subset of patients exhibited HSV-related organ damage, including pneumonia and hepatitis (10.2% and 2.3%, respectively). The mortality rate in HSV-viremic patients was not significantly increased compared to the overall mortality rate in the ICU (27.3% vs. 22.9%, p = 0.33). Only patients with high HSV viral loads tended to have a higher, though non-significant, death rate (57.1%, p = 0.14). CONCLUSIONS: Our results suggest HSV viremia is common in ICU patients, potentially favored by immunocompromised status and mechanical ventilation. The global impact of HSV-viremia on mortality in the ICU was low. Quantifying HSV DNA may help identifying patients at-risk of severe HSV-induced symptoms.


Assuntos
Herpes Simples/diagnóstico , Herpes Simples/patologia , Unidades de Terapia Intensiva , Simplexvirus/isolamento & purificação , Viremia/diagnóstico , Viremia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sangue/virologia , Feminino , Herpes Simples/epidemiologia , Herpes Simples/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Análise de Sobrevida , Viremia/epidemiologia , Viremia/mortalidade
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