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1.
Artigo em Inglês | MEDLINE | ID: mdl-34739391

RESUMO

INTRODUCTION: Ticks are frequently polyinfected and can thus transmit numerous microorganisms. A large number of bacteria, parasites and viruses are transmitted by tick bites and could cause different signs and symptoms in patients. The main goal of this study was to search for these numerous microorganisms in patients presenting with persistent polymorphic syndrome possibly due to a tick bite (SPPT). PATIENTS AND METHODS: The following microorganisms were searched for in saliva, urine, venous and capillary blood by using real time PCR: Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Borrelia hermsii, Bartonella spp., Bartonella quintana, Bartonella henselae, Ehrlichia spp., Anaplasma spp., Rickettsia spp., Coxiella burnetii, Brucella spp., Francisella tularensis, Mycoplasma spp., Chlamydia spp., Babesia spp., Theileria spp. RESULTS: 104 patients were included. 48% of the patients were poly-infected, and 25% harboured at least three different microorganisms. Borrelia spp. were not the most frequent bacteria observed, observed far behind Mycoplasma spp., Rickettsia spp. and Ehrlichia spp. which were the most frequent microorganisms observed. Piroplasms were found in a significant number of patients. The most sensitive matrix was saliva, followed by urine, capillary blood and venous blood. CONCLUSION: Our prospective study has shown that patients with SPPT, a syndrome close to fibromyalgia, could harbour several tick borne microorganisms.

3.
Front Med (Lausanne) ; 7: 55, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32181254

RESUMO

Background: Borrelia species are divided into three groups depending on the induced disease and the tick vector. Borrelia miyamotoi is a relapsing fever Borrelia but can induce symptoms related to Lyme disease. Discovered in 1995, it is found in ticks around the world. In France, this species of Borrelia has been isolated in ticks and rodents, but was not yet observed in humans. Objective: The aim of the study was to look for B. miyamotoi in symptomatic patients. Methods: Real-time PCR was performed on 824 blood samples from patients presenting symptoms of persistent polymorphic syndrome possibly due to tick bite, a syndrome recognized by the French Authority for Health, which is close to the post-treatment Lyme disease syndrome. PCR was also performed on 24 healthy control persons. The primers were specifically designed for this particular species of Borrelia. The sequence of interest of 94 bp is located on the glpQ gene. Sequencing of amplification products, randomly chosen, confirmed the amplification specificity. To better investigate cases, a clinical questionnaire was sent to the patients PCR-positive for B. miyamotoi and to their physician. Results: This search revealed a positive PCR for B. miyamotoi in the blood from 43 patients out of 824 (5.22%). PCR was negative in all control persons. A clinical chart was obtained from 31 of the 43 patients. A history of erythema migrans was reported in five of these 31 patients (16%). All patients complained about fatigue, joint pain and neuro-cognitive disorders. Some patients complained about respiratory problems (chest tightness and/or lack of air in 41.9%). Episodes of relapsing fever were reported by 11 of the 31 patients (35.5%). Chilliness, hot flushes and/or sweats were reported by around half of the patients. B. miyamotoi may not cross-react with B. burgdorferi serology. Conclusion: This study is the first to detect B. miyamotoi in human blood in France. This series of human B. miyamotoi infection is the largest in patients with long term persistent syndrome. Our data suggest that this infection may be persistent, even on the long term.

4.
PLoS One ; 7(11): e50235, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226251

RESUMO

Ischemia/reperfusion injury occurring during liver transplantation is mainly due to the generation of reactive oxygen species (ROS) upon revascularization. Thus, delivery of antioxidant enzymes might reduce the deleterious effects of ROS and improve liver graft initial function. Mangafodipir trisodium (MnDPDP), a contrast agent currently used in magnetic resonance imaging of the liver, has been shown to be endowed with powerful antioxidant properties. We hypothesized that MnDPDP could have a protective effect against liver ischemia reperfusion injury when administrated to the donor prior to harvesting. Livers from Sprague Dawley rats pretreated or not with MnDPDP were harvested and subsequently preserved for 24 h in Celsior® solution at 4°C. Organs were then perfused ex vivo for 120 min at 37°C with Krebs Henseleit solution. In MnDPDP (5 µmol/kg) group, we observed that ATP content was significantly higher at the end of the cold preservation period relative to untreated group. After reperfusion, livers from MnDPDP-treated rats showed better tissue integrity, less hepatocellular and endothelial cell injury. This was accompanied by larger amounts of bile production and higher ATP recovery as compared to untreated livers. The protective effect of MnDPDP was associated with a significant decrease of lipid peroxidation, mitochondrial damage, and apoptosis. Interestingly, MnDPDP-pretreated livers exhibited activation of Nfr2 and HIF-1α pathways resulting in a higher catalase and HO-1 activities. MnDPDP also increased total nitric oxide (NO) production which derived from higher expression of constitutive NO synthase and lower expression of inducible NO synthase. In conclusion, our results show that donor pretreatment with MnDPDP protects the rat liver graft from cold ischemia/reperfusion injury and demonstrate for the first time the potential interest of this molecule in the field of organ preservation. Since MnDPDP is safely used in liver imaging, this preservation strategy holds great promise for translation to clinical liver transplantation.


Assuntos
Antioxidantes/farmacologia , Ácido Edético/análogos & derivados , Transplante de Fígado , Fígado/efeitos dos fármacos , Soluções para Preservação de Órgãos/farmacologia , Disfunção Primária do Enxerto/prevenção & controle , Fosfato de Piridoxal/análogos & derivados , Espécies Reativas de Oxigênio/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Catalase/genética , Catalase/metabolismo , Ácido Edético/farmacologia , Expressão Gênica/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/imunologia , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Técnicas de Cultura de Órgãos , Preservação de Órgãos , Soluções para Preservação de Órgãos/química , Disfunção Primária do Enxerto/imunologia , Disfunção Primária do Enxerto/metabolismo , Fosfato de Piridoxal/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Transplante/efeitos dos fármacos
5.
Int J Hepatol ; 2012: 137676, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23094162

RESUMO

Glutathione transferases (GST) are essentially known as enzymes that catalyse the conjugation of glutathione to various electrophilic compounds such as chemical carcinogens, environmental pollutants, and antitumor agents. However, this protein family is also involved in the metabolism of endogenous compounds which play critical roles in the regulation of signaling pathways. For example, the lipid peroxidation product 4-hydroxynonenal (4-HNE) and the prostaglandin 15-deoxy-Δ12,14-prostaglandin J(2) (15d-PGJ(2)) are metabolized by GSTs and these compounds are known to influence the activity of transcription factors and protein kinases involved in stress response, proliferation, differentiation, or apoptosis. Furthermore, several studies have demonstrated that GSTs are able to interact with different protein partners such as mitogen activated protein kinases (i.e., c-jun N-terminal kinase (JNK) and apoptosis signal-regulating kinase 1 (ASK1)) which are also involved in cell signaling. New functions of GSTs, including S-glutathionylation of proteins by GSTs and ability to be a nitric oxide (NO) carrier have also been described. Taken together, these observations strongly suggest that GST might play a crucial role during normal or cancer cells proliferation or apoptosis.

6.
J Pharmacol Exp Ther ; 342(3): 676-87, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22647274

RESUMO

Clinical investigations suggest that hepatotoxicity after acetaminophen (APAP) overdose could be more severe in the context of obesity and nonalcoholic fatty liver disease. The pre-existence of fat accumulation and CYP2E1 induction could be major mechanisms accounting for such hepatic susceptibility. To explore this issue, experiments were performed in obese diabetic ob/ob and db/db mice. Preliminary investigations performed in male and female wild-type, ob/ob, and db/db mice showed a selective increase in hepatic CYP2E1 activity in female db/db mice. However, liver triglycerides in these animals were significantly lower compared with ob/ob mice. Next, APAP (500 mg/kg) was administered in female wild-type, ob/ob, and db/db mice, and investigations were carried out 0.5, 2, 4, and 8 h after APAP intoxication. Liver injury 8 h after APAP intoxication was higher in db/db mice, as assessed by plasma transaminases, liver histology, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. In db/db mice, however, the extent of hepatic glutathione depletion, levels of APAP-protein adducts, c-Jun N-terminal kinase activation, changes in gene expression, and mitochondrial DNA levels were not greater compared with the other genotypes. Furthermore, in the db/db genotype plasma lactate and ß-hydroxybutyrate were not specifically altered, whereas the plasma levels of APAP-glucuronide were intermediary between wild-type and ob/ob mice. Thus, early APAP-induced hepatotoxicity was greater in db/db than ob/ob mice, despite less severe fatty liver and similar basal levels of transaminases. Hepatic CYP2E1 induction could have an important pathogenic role when APAP-induced liver injury occurs in the context of obesity and related metabolic disorders.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fígado/efeitos dos fármacos , Obesidade/metabolismo , Ácido 3-Hidroxibutírico/sangue , Acetaminofen/sangue , Animais , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocromo P-450 CYP2E1/metabolismo , DNA Mitocondrial/metabolismo , Fígado Gorduroso/sangue , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Feminino , Glucuronídeos/sangue , Glutationa/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Ácido Láctico/sangue , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Obesidade/sangue , Obesidade/patologia , Sulfatos/sangue , Triglicerídeos/sangue
7.
Hum Mutat ; 33(11): 1557-65, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22678879

RESUMO

Genotype-phenotype correlations in cystic fibrosis (CF) may be difficult to establish because of phenotype variability, which is associated with certain CF transmembrane conductance regulator (CFTR) gene mutations and the existence of complex alleles. To elucidate the clinical significance of complex alleles involving p.Gly149Arg, p.Asp443Tyr, p.Gly576Ala, and p.Arg668Cys, we performed a collaborative genotype-phenotype correlation study, collected epidemiological data, and investigated structure-function relationships for single and natural complex mutants, p.[Gly576Ala;Arg668Cys], p.[Gly149Arg;Gly576Ala;Arg668Cys], and p.[Asp443Tyr;Gly576Ala;Arg668Cys]. Among 153 patients carrying at least one of these mutations, only three had classical CF and all carried p.Gly149Arg in the triple mutant. Sixty-four had isolated infertility and seven were healthy individuals with a severe mutation in trans, but none had p.Gly149Arg. Functional studies performed on all single and natural complex mutants showed that (1) p.Gly149Arg results in a severe misprocessing defect; (2) p.Asp443Tyr moderately alters CFTR maturation; and (3) p.Gly576Ala, a known splicing mutant, and p.Arg668Cys mildly alter CFTR chloride conductance. Overall, the results consistently show the contribution of p.Gly149Arg to the CF phenotype, and suggest that p.[Arg668Cys], p.[Gly576Ala;Arg668Cys], and p.[Asp443Tyr;Gly576Ala;Arg668Cys] are associated with CFTR-related disorders. The present study emphasizes the importance of comprehensive genotype-phenotype and functional studies in elucidating the impact of mutations on clinical phenotype.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Proteínas Mutantes/genética , Mutação , Alelos , Substituição de Aminoácidos , Fibrose Cística/fisiopatologia , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , França , Frequência do Gene , Estudos de Associação Genética , Células HeLa , Heterozigoto , Humanos , Proteínas Mutantes/química , Proteínas Mutantes/fisiologia , Mutação de Sentido Incorreto , Estrutura Terciária de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
8.
Lab Invest ; 92(3): 396-410, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22157718

RESUMO

Although carbon tetrachloride (CCl(4))-induced acute and chronic hepatotoxicity have been extensively studied, little is known about the very early in vivo effects of this organic solvent on oxidative stress and mitochondrial function. In this study, mice were treated with CCl(4) (1.5 ml/kg ie 2.38 g/kg) and parameters related to liver damage, lipid peroxidation, stress/defense and mitochondria were studied 3 h later. Some CCl(4)-intoxicated mice were also pretreated with the cytochrome P450 2E1 inhibitor diethyldithiocarbamate or the antioxidants Trolox C and dehydroepiandrosterone. CCl(4) induced a moderate elevation of aminotransferases, swelling of centrilobular hepatocytes, lipid peroxidation, reduction of cytochrome P4502E1 mRNA levels and a massive increase in mRNA expression of heme oxygenase-1 and heat shock protein 70. Moreover, CCl(4) intoxication induced a severe decrease of mitochondrial respiratory chain complex IV activity, mitochondrial DNA depletion and damage as well as ultrastructural alterations. Whereas DDTC totally or partially prevented all these hepatic toxic events, both antioxidants protected only against liver lipid peroxidation and mitochondrial damage. Taken together, our results suggest that lipid peroxidation is primarily implicated in CCl(4)-induced early mitochondrial injury. However, lipid peroxidation-independent mechanisms seem to be involved in CCl(4)-induced early hepatocyte swelling and changes in expression of stress/defense-related genes. Antioxidant therapy may not be an efficient strategy to block early liver damage after CCl(4) intoxication.


Assuntos
Intoxicação por Tetracloreto de Carbono/metabolismo , Hepatócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono , Cromanos/farmacologia , Inibidores do Citocromo P-450 CYP2E1 , Desidroepiandrosterona/farmacologia , Ditiocarb/farmacologia , Masculino , Camundongos , Mitocôndrias Hepáticas/efeitos dos fármacos
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