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1.
Infect Immun ; 84(11): 3152-3160, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27550933

RESUMO

Serotype 19A strains have emerged as a cause of invasive pneumococcal disease after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7), and serotype 19A has now been included in the recent 13-valent vaccine (PCV13). Genetic analysis has revealed at least three different capsular serotype 19A subtypes, and nutritional environment-dependent variation of the 19A capsule structure has been reported. Pneumococcal vaccine effectiveness and serotyping accuracy might be impaired by structural differences in serotype 19A capsules. We therefore analyzed the distribution of 19A subtypes collected within a Swiss national surveillance program and determined capsule composition under different nutritional conditions with high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR) spectroscopy. After the introduction of PCV7, a significant relative increase of subtype 19A-II and decrease of 19A-I occurred. Chemical analyses showed no difference in the composition as well as the linkage of 19A subtype capsular saccharides grown in defined and undefined growth media, which is consistent with a trisaccharide repeat unit composed of rhamnose, N-acetyl-mannosamine, and glucose. In summary, our study suggests that no structural variance dependent of the nutritional environment or the subtype exists. The serotype 19A subtype shift observed after the introduction of the PCV7 can therefore not be explained by selection of a capsule structure variant. However, capsule composition analysis of emerging 19A clones is recommended in cases where there is no other explanation for a selective advantage, such as antibiotic resistance or loss or acquisition of other virulence factors.


Assuntos
Cápsulas Bacterianas/química , Infecções Pneumocócicas/microbiologia , Polissacarídeos/química , Streptococcus pneumoniae/fisiologia , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética , Vigilância da População , Análise de Regressão , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/classificação
2.
J Neuroinflammation ; 11: 169, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25274277

RESUMO

BACKGROUND: Bacterial meningitis (BM) is characterized by an intense host inflammatory reaction, which contributes to the development of brain damage and neuronal sequelae. Activation of the kynurenine (KYN) pathway (KP) has been reported in various neurological diseases as a consequence of inflammation. Previously, the KP was shown to be activated in animal models of BM, and the association of the SNP AADAT + 401C/T (kynurenine aminotransferase II - KAT II) with the host immune response to BM has been described. The aim of this study was to investigate the involvement of the KP during BM in humans by assessing the concentrations of KYN metabolites in the cerebrospinal fluid (CSF) of BM patients and their relationship with the inflammatory response compared to aseptic meningitis (AM) and non-meningitis (NM) groups. METHODS: The concentrations of tryptophan (TRP), KYN, kynurenic acid (KYNA) and anthranilic acid (AA) were assessed by HPLC from CSF samples of patients hospitalized in the Giselda Trigueiro Hospital in Natal (Rio Grande do Norte, Brazil). The KYN/TRP ratio was used as an index of indoleamine 2,3-dioxygenase (IDO) activity, and cytokines were measured using a multiplex cytokine assay. The KYNA level was also analyzed in relation to AADAT + 401C/T genotypes. RESULTS: In CSF from patients with BM, elevated levels of KYN, KYNA, AA, IDO activity and cytokines were observed. The cytokines INF-γ and IL-1Ra showed a positive correlation with IDO activity, and TNF-α and IL-10 were positively correlated with KYN and KYNA, respectively. Furthermore, the highest levels of KYNA were associated with the AADAT + 401 C/T variant allele. CONCLUSION: This study suggests a downward modulatory effect of the KP on CSF inflammation during BM.


Assuntos
Citocinas/líquido cefalorraquidiano , Inflamação/líquido cefalorraquidiano , Cinurenina/líquido cefalorraquidiano , Meningites Bacterianas/líquido cefalorraquidiano , Adolescente , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Adulto Jovem
3.
Pediatr Res ; 72(6): 568-75, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23007029

RESUMO

BACKGROUND: Preconditioning of neonatal mice with nonlethal hypoxia (HPC) protects the brain from hypoxic-ischemic (HI) injury. Overexpression of human glutathione peroxidase 1 (GPx1), which normally protects the developing murine brain from HI injury, reverses HPC protection, suggesting that a certain threshold of hydrogen peroxide concentration is required for activation of HPC signaling. METHODS: Activation (phosphorylation) of extracellular-regulated kinase (ERK) 1/2 and Akt, and induction of hypoxia-inducible factor (HIF)-1α were assessed in the cortex, one of the main structures affected by HI and protected by HPC, at different time points after reoxygenation in wild-type (WT) and GPx1-overexpressing animals. RESULTS: GPx1 overexpression prevented both the global and nuclear increase in activated ERK at 0.5 h after HPC and caused a significant decrease in phospho-ERK (pERK)/ERK levels at 24 h after HPC. In contrast, HIF-1α induction at the end of hypoxia was unaffected by GPx1 overexpression. In the cortex of preconditioned WT animals, enhanced pERK staining was primarily observed in neurons and to a lower extent in astrocytes and endothelial cells, with a nuclear prominence. CONCLUSION: Aberrant activation of ERK probably explains the paradoxical reversal of HPC protection by GPx1 overexpression. The results identify hydrogen peroxide as an important mediator of neuroprotective ERK signaling.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glutationa Peroxidase/metabolismo , Animais , Animais Recém-Nascidos , Ativação Enzimática , Camundongos , Fosforilação
4.
Neurobiol Dis ; 41(1): 201-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20875857

RESUMO

Pneumococcal meningitis causes apoptosis of developing neurons in the dentate gyrus of the hippocampus. The death of these cells is accompanied with long-term learning and memory deficits in meningitis survivors. Here, we studied the role of the PI3K/Akt (protein kinase B) survival pathway in hippocampal apoptosis in a well-characterized infant rat model of pneumococcal meningitis. Meningitis was accompanied by a significant decrease of the PI3K product phosphatidylinositol 3,4,5-trisphosphate (PIP(3)) and of phosphorylated (i.e., activated) Akt in the hippocampus. At the cellular level, phosphorylated Akt was decreased in both the granular layer and the subgranular zone of the dentate gyrus, the region where the developing neurons undergo apoptosis. Protein levels and activity of PTEN, the major antagonist of PI3K, were unaltered by infection, suggesting that the observed decrease in PIP(3) and Akt phosphorylation is a result of decreased PI3K signaling. Treatment with the PTEN inhibitor bpV(pic) restored Akt activity and significantly attenuated hippocampal apoptosis. Co-treatment with the specific PI3K inhibitor LY294002 reversed the restoration of Akt activity and attenuation of hippocampal apoptosis, while it had no significant effect on these parameters on its own. These results indicate that the inhibitory effect of bpV(pic) on apoptosis was mediated by PI3K-dependent activation of Akt, strongly suggesting that bpV(pic) acted on PTEN. Treatment with bpV(pic) also partially inhibited the concentration of bacteria and cytokines in the CSF, but this effect was not reversed by LY294002, indicating that the effect of bpV(pic) on apoptosis was independent of its effect on CSF bacterial burden and cytokine levels. These results indicate that the PI3K/Akt pathway plays an important role in the death and survival of developing hippocampal neurons during the acute phase of pneumococcal meningitis.


Assuntos
Apoptose/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Meningite Pneumocócica/tratamento farmacológico , Degeneração Neural/tratamento farmacológico , Compostos Organometálicos/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Modelos Animais de Doenças , Hipocampo/enzimologia , Hipocampo/patologia , Meningite Pneumocócica/enzimologia , Meningite Pneumocócica/patologia , Degeneração Neural/enzimologia , Degeneração Neural/microbiologia , Compostos Organometálicos/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
5.
Forensic Sci Int Synerg ; 3: 100148, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095801

RESUMO

Today, there is a real political urge to see the sharing of ballistic data intensify across Europe mostly due to recent events such as terrorist attacks. However, technical constraints remain and two main options are being discussed. The first one relies on a centralized common database, implying a vendor monopoly for all Europe and a unified protocol among member states. The second one advocates for a distributed framework relying on existing national infrastructures and leaving each country responsible for its own protocols. This article describes a prototype network linking Switzerland and France using the Evofinder® system by ScannBI. We will first focus on how this network was set up, and then report some results from tests conducted to assess the viability of the concept. These results demonstrate that the second option cannot be discarded and pave the way for a distributed network. This solution appears to be cheaper, more adaptable and answers the practical needs of member states.

6.
Psychother Res ; 20(2): 203-13, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19844843

RESUMO

The aim of this exploratory study was to examine the possible mechanisms of behavioral change in a cognitive-behavioral intervention supporting medication adherence in HIV-infected persons. A total of 60 persons currently under medical treatment were randomized to psychotherapy or usual care and were compared with a sociodemographically matched group of general psychotherapy clients. Outcome measures included therapy adherence using medication event-monitoring system psychotherapeutic processes and changes of experience and behavior. The general psychotherapy group was initially more distressed than HIV psychotherapy patients and reached higher levels of psychotherapeutic effect. In the HIV psychotherapy patients, a significant effect was found for maintaining adherence to medical treatment (Weber et al., 2004). These findings show that psychotherapy is a beneficial intervention for HIV-infected persons, and therapeutic alliance and activation of resources do not differ from a general psychotherapy treatment. Differential effects were detected for specific process variables, namely problem actuation.


Assuntos
Antivirais/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/terapia , Promoção da Saúde , Cooperação do Paciente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Sci Justice ; 60(1): 63-71, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31924290

RESUMO

The aim of this study was to compare three gunshot residue (GSR) collection methods used in conjunction with chemographic detection applied by different regional Swiss police services. The specimens were collected from the hands of a shooter with either filter paper (Filter method) or adhesive foil. The adhesive foil was then either applied against photographic paper during visualisation (AF Photo method) or coated with a layer of polyvinyl alcohol (AF PVAL method). The experiments involved two conditions of the examined hands, i.e. dry and humidified. The residues were revealed using the sodium rhodizonate test (SRT). Preliminary tests assessing the possibility of conducting a confirmatory Scanning Electron Microscopy coupled to Energy Dispersive X-ray spectroscopy (SEM/EDX) analysis after the chemographic test were performed on a number of specimens by cutting positive spots and mounting them on stubs. Obtained results were compared in terms of effectiveness - number of positive spots, time requirements, quality of subsequent SEM-EDX analysis, ease of use and cost. The Filter method generally yielded a high-quality detection with both dry and humidified hands, as well as a simple, quick and efficient confirmation by SEM/EDX. The AF Photo performed well on dry hands, but not on humidified hands. The AF PVAL method performance was lower compared to the other methods in both examined conditions of the hands. The SEM/EDX analysis showed that the Filter and AF PVAL method provided satisfactory results when a sufficient carbon coating thickness was applied to the cuttings. It was also observed that the thinner the PVAL layer, the better the quality of the spectra and obtained images in SEM/EDX. Furthermore, the surface of the photographic paper did not seem to be conductive, even after the application of a thick layer of carbon. In conclusion, the Filter method gave the best overall results, but its application required slightly more time and expertise than the two other methods.


Assuntos
Balística Forense/métodos , Medicina Legal/métodos , Mãos , Manejo de Espécimes/métodos , Ferimentos por Arma de Fogo , Cicloexanonas/análise , Humanos , Aplicação da Lei , Microscopia Eletrônica de Varredura , Pele/química , Espectrometria por Raios X , Suíça
8.
Forensic Sci Int ; 295: 64-71, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30572221

RESUMO

The Glock company's newest generation of pistols (G42/43, Gen5) is equipped with so-called "Glock Marksman Barrels" (GMB). These barrels feature an enhanced polygonal profile with right-hand twist and a small rifled profile on either side of the main polygonal field impression (Hernandez et al., 2016). Up until now, using the usual methods of comparison (automatic ballistic identification systems, ABIS and comparison microscope) it was difficult to assign bullets fired from a polygonal barrel to their origin with a high evidentiary value (Murdock et al., 1990) [5] (Northcutt, 2010). In this study, test shots from 18 Glock Gen5 pistols (9 Glock 17 pistols and 9 Glock 19 pistols) were compared to examine their differentiability. In addition, a Gen5 Glock 17 pistol was used to shoot 500 cartridges to determine to what degree the first projectile could be matched with the 500th (Zhang and Luo, 2018) [10]. This study was able to demonstrate that the new "Glock Marksman Barrel" (GMB) leaves marks of sufficient quality on projectiles to make high evidentiary value assignments of those projectiles to an individual firearm, both by using the comparison microscope as well as with an ABIS (Evofinder®). Further, it was possible to assign the cartridge casings to an individual pristine firearm.

9.
Neurobiol Dis ; 32(1): 142-50, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18703144

RESUMO

Pneumococcal meningitis is associated with caspase 3-dependent apoptosis of recently post-mitotic immature neurons in the dentate gyrus of the hippocampus. The death of these cells is implicated in the learning and memory deficits in patients surviving the disease. The stress-activated protein kinase c-Jun N-terminal kinase (JNK) has been shown to be an important mediator of caspase 3-dependent neuronal apoptosis. However, whether JNK is involved in hippocampal apoptosis caused by pneumococcal meningitis has so far not been investigated. Here we show in a neonatal rat model of pneumococcal meningitis that JNK3 but not JNK1 or JNK2 is activated in the hippocampus during the acute phase of infection. At the cellular level, JNK3 activation was accompanied in the dentate gyrus by markedly increased phosphorylation of its major downstream target c-Jun in early immature (Hu-positive) neurons, but not in migrating (doublecortin-positive) neurons, the cells that do undergo apoptosis. These findings suggested that JNK may not be involved in pneumococcal meningitis-induced hippocampal apoptosis. Indeed, although intracerebroventricular administration of D-JNKI-1 or AS601245 (two highly specific JNK inhibitors) inhibited c-Jun phosphorylation and protein expression in the hippocampus, hippocampal apoptosis was unaffected. Collectively, these results demonstrate that JNK does not mediate hippocampal apoptosis in pneumococcal meningitis, and that JNK may be involved in processes unrelated to apoptosis in this disease.


Assuntos
Apoptose/fisiologia , Hipocampo/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Meningite Pneumocócica/enzimologia , Neurônios/enzimologia , Animais , Animais Recém-Nascidos , Proteína Duplacortina , Ativação Enzimática/fisiologia , Hipocampo/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Meningite Pneumocócica/patologia , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Neurônios/patologia , Ratos , Ratos Wistar
10.
Int J Dev Neurosci ; 26(1): 87-92, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17935927

RESUMO

Oxidative stress is a critical component of the injury response to hypoxia-ischemia (HI) in the neonatal brain, and this response is unique and at times paradoxical to that seen in the mature brain. Previously, we showed that copper-zinc superoxide-dismutase (SOD1) over-expression is not beneficial to the neonatal mouse brain with HI injury, unlike the adult brain with ischemic injury. However, glutathione peroxidase 1 (GPx1) over-expression is protective to the neonatal mouse brain with HI injury. To further test the hypothesis that an adequate supply of GPx is critical to protection from HI injury, we crossed SOD1 over-expressing mice (hSOD-tg) with GPx1 over-expressing mice (hGPx-tg). Resulting litters contained wild-type (wt), hGPx-tg, hSOD-tg and hybrid hGPx-tg/hSOD-tg pups, which were subjected to HI at P7. Confirming previous results, the hGPx-tg mice had reduced injury compared to both Wt and hSOD-tg littermates. Neonatal mice over-expressing both GPx1 and SOD1 also had less injury compared to wt or hSOD-tg alone. A result of oxidative stress after neonatal HI is a decrease in the concentration of reduced (i.e. antioxidant-active) glutathione (GSH). In this study, we tested the effect of systemic administration of alpha-lipoic acid on levels of GSH in the cortex after HI. Although GSH levels were restored by 24h after HI, injury was not reduced compared to vehicle-treated mice. We also tested two other pharmacological approaches to reducing oxidative stress in hSOD-tg and wild-type littermates. Both the specific inhibitor of neuronal nitric oxide synthase, 7-nitroindazole (7NI), and the spin-trapping agent alpha-phenyl-tert-butyl-nitrone (PBN) did not reduce HI injury, however. Taken together, these results imply that H2O2 is a critical component of neonatal HI injury, and GPx1 plays an important role in the defense against this H2O2 and is thereby neuroprotective.


Assuntos
Antioxidantes/farmacologia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Ácido Tióctico/farmacologia , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Peroxidase/genética , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/fisiologia , Superóxido Dismutase/genética , Superóxido Dismutase-1 , Glutationa Peroxidase GPX1
11.
Mol Aspects Med ; 28(5-6): 668-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17316780

RESUMO

Natural vitamin E consists of four different tocopherol and four different tocotrienol homologues (alpha,beta, gamma, delta) that all have antioxidant activity. However, recent data indicate that the different vitamin E homologues also have biological activity unrelated to their antioxidant activity. In this review, we discuss the anti-inflammatory properties of the two major forms of vitamin E, alpha-tocopherol (alphaT) and gamma-tocopherol (gammaT), and discuss the potential molecular mechanisms involved in these effects. While both tocopherols exhibit anti-inflammatory activity in vitro and in vivo, supplementation with mixed (gammaT-enriched) tocopherols seems to be more potent than supplementation with alphaT alone. This may explain the mostly negative outcomes of the recent large-scale interventional chronic disease prevention trials with alphaT only and thus warrants further investigation.


Assuntos
Anti-Inflamatórios/farmacologia , alfa-Tocoferol/farmacologia , gama-Tocoferol/farmacologia , Animais , Humanos
12.
Exp Biol Med (Maywood) ; 232(2): 309-22, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17259339

RESUMO

Neonatal cattle and in part neonates of other species have manyfold higher plasma concentrations of nitrite plus nitrate than mature cows and subjects of other species, suggesting an enhanced and needed activation of the nitric oxide (NO) axis at birth. While the biological half-life of NO is short (<1 sec), its functionality can be prolonged, and in many regards more discretely modulated, when it reacts with low-molecular-weight and protein-bound thiols to form S-nitrosothiols (RSNO), from which NO subsequently can be rereleased. We used the calf as a model to test the hypothesis that plasma concentrations of RSNO are elevated at birth in mammals, correlate with ascorbate and urate levels, are selectively generated in critical tissue beds, and are generated in a manner temporally coincident with changes in tissue levels of active NO synthases (NOS). Plasma concentrations of RSNO, ascorbate, and urate were highest immediately after birth (Day 0), dropped >50% on Day 1, and gradually decreased over time, reaching a nadir in mature cattle. Albumin and immunoglobulin G were identified as major plasma RSNO. The presence of S-nitrosocysteine (SNC, a validated marker for S-nitrosylated proteins), inducible NOS (iNOS), and activated endothelial NOS (eNOS phosphorylated at Ser1177) in different tissues was analyzed by immunohistochemistry in another group of similar-aged calves. SNC, iNOS, and phosphorylated eNOS were detected in liver and ileum at the earliest timepoint of sampling (4 hrs after birth), increased between 4 and 24 hrs, and then declined to near-nondetectable levels by 2 weeks of life. Our data show that the neonatal period in the bovine species is characterized by highly elevated and coordinated NO-generating and nitrosylation events, with the ontogenetic changes occurring in iNOS and eNOS contents in key tissues as well as RSNO products and associated antioxidant markers.


Assuntos
S-Nitrosotióis/sangue , Animais , Animais Recém-Nascidos , Proteínas Sanguíneas/metabolismo , Bovinos , Óxido Nítrico Sintase/sangue
13.
Forensic Sci Int ; 273: 10-19, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28189934

RESUMO

Unburned propellant powder particles in gunshot residue (GSR) were detected at near infrared by optical excitation in the visible wavelength range. A series of ammunition (different brands and different manufacturers) was analyzed concerning the luminescence of their propellant. Shooting target samples with different shooting distances were produced on standard textile tissue and analyzed with this optical infrared inspection. The number of luminescent GSR particles per area was measured and curves with particle density vs. shooting distance were drawn. The method was applied on three ammunition types with different particle morphology shot with a pistol and one ammunition type shot with a revolver. The shooting series performed with the revolver showed a large particle density variation within the samples of identical shooting distances. In this case, the ratio of the amount of particles within the area around the bullet hole and within a ring with a defined distance from the bullet hole was calculated. These data resulted in measures with much lower standard deviations, which is a prove that the distribution pattern depends on the shooting distance and not on the amount of GSR particles. It has been shown, that imaging of target tissue with the aid of infrared luminescence is an easy, fast, reproducible and non-destructive method for shooting-distance determination.

14.
Free Radic Biol Med ; 41(9): 1372-83, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17023264

RESUMO

N-acetylcysteine (NAC) is neuroprotective in animal models of acute brain injury such as caused by bacterial meningitis. However, the mechanism(s) by which NAC exerts neuroprotection is unclear. Gene expression of endothelin-1 (ET-1), which contributes to cerebral blood flow decline in acute brain injury, is partially regulated by reactive oxygen species, and thus a potential target of NAC. We therefore examined the effect of NAC on tumor necrosis factor (TNF)-alpha-induced ET-1 production in cerebrovascular endothelial cells. NAC dose dependently inhibited TNF-alpha-induced preproET-1 mRNA upregulation and ET-1 protein secretion, while upregulation of inducible nitric oxide synthase (iNOS) was unaffected. Intriguingly, NAC had no effect on the initial activation (i.e., IkappaB degradation, nuclear p65 translocation, and Ser536 phosphorylation) of NF-kappaB by TNF-alpha. However, transient inhibition of NF-kappaB DNA binding suggested that NAC may inhibit ET-1 upregulation by inhibiting (a) parallel pathway(s) necessary for full transcriptional activation of NF-kappaB-mediated ET-1 gene expression. Similar to NAC, the MEK1/2 inhibitor U0126, the p38 inhibitor SB203580, and the protein kinase inhibitor H-89 selectively inhibited ET-1 upregulation without affecting nuclear p65 translocation, suggesting that NAC inhibits ET-1 upregulation via inhibition of mitogen- and stress-activated protein kinase (MSK). Supporting this notion, cotreatment with NAC inhibited the TNF-alpha-induced rise in MSK1 and MSK2 kinase activity, while siRNA knock-down experiments showed that MSK2 is the predominant isoform involved in TNF-alpha-induced ET-1 upregulation.


Assuntos
Acetilcisteína/farmacologia , Encéfalo/metabolismo , Endotelina-1/metabolismo , Endotélio Vascular/metabolismo , Sequestradores de Radicais Livres/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Encéfalo/citologia , Linhagem Celular , Endotelina-1/genética , Endotélio Vascular/citologia , Inibidores Enzimáticos/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , NF-kappa B/metabolismo , Nitratos/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Fosforilação , Transporte Proteico , Ratos , Regulação para Cima
15.
PLoS One ; 11(12): e0168541, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28002439

RESUMO

Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R) injury during myocardial infarction (MI). Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS). We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5) or saline (n = 5) was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group) as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE), endothelial cell activation (CD31) and inflammation (IgG, C3b/c, C5b9, MCP-1) were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.


Assuntos
Dexrazoxano/uso terapêutico , Infarto do Miocárdio/etiologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Doença Aguda , Administração Intravenosa , Animais , Quimiocina CCL2/metabolismo , Complemento C3c/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Dexrazoxano/farmacologia , Modelos Animais de Doenças , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/complicações , Miocárdio/patologia , Necrose , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco , Suínos , Troponina I/sangue , Função Ventricular Esquerda/efeitos dos fármacos
16.
Free Radic Biol Med ; 38(10): 1323-32, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15855050

RESUMO

Oxidative stress seems to contribute to cardiopulmonary bypass (CPB)-related postoperative complications. Pediatric patients are particularly prone to these complications. With this in mind, we measured oxidative stress markers in blood plasma of 20 children undergoing elective heart surgery before, during, and up to 48 h after cessation of CPB, along with inflammatory parameters and full analysis of iron status. Ascorbate levels were decreased by approximately 50% (P < 0.001) at the time of aorta cross-clamp removal (or pump switch-off in 4 patients with partial CPB), and associated with corresponding increases in dehydroascorbate (P < 0.001, r = -0.80) and malondialdehyde (P < 0.01, r = -0.59). In contrast to the immediate oxidative response, peak levels of IL-6 and IL-8 were not observed until 3-12 h after CPB cessation. The early loss of ascorbate correlated with duration of CPB (P < 0.002, r = 0.72), plasma hemoglobin after cross-clamp removal (P < 0.001, r = 0.70), and IL-6 and IL-8 levels at 24 and 48 h after CPB (P < 0.01), but not with postoperative lactate levels, strongly suggesting that hemolysis, and not inflammation or ischemia, was the main cause of early oxidative stress. The correlation of ventilation time with early changes in ascorbate (P < 0.02, r = 0.55), plasma hemoglobin (P < 0.01, r = 0.60), and malondialdehyde (P < 0.02, r = 0.54) suggests that hemolysis-induced oxidative stress may be an underlying cause of CPB-associated pulmonary dysfunction. Optimization of surgical procedures or therapeutic intervention that minimize hemolysis (e.g., off-pump surgery) or the resultant oxidative stress (e.g., antioxidant treatment) should be considered as possible strategies to lower the rate of postoperative complications in pediatric CPB.


Assuntos
Ponte Cardiopulmonar , Cardiopatias Congênitas/cirurgia , Estresse Oxidativo/imunologia , Pneumonia/imunologia , Complicações Pós-Operatórias/etiologia , Ácido Ascórbico/metabolismo , Proteína C-Reativa/metabolismo , Procedimentos Cirúrgicos Cardíacos , Criança , Pré-Escolar , Ácido Desidroascórbico/metabolismo , Hemólise/imunologia , Humanos , Lactente , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Ferro/metabolismo , Isquemia , Malondialdeído/metabolismo , Neutrófilos/metabolismo , Pneumonia/patologia , Estudos Prospectivos
17.
Pflege ; 18(1): 25-37, 2005 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-15768916

RESUMO

In the Clinic for Nuclear Medicine and Radiotherapy, City Hospital Triemli (Zurich, Switzerland), a controlled observational study was carried out. The investigation aimed at comparing conventional and kinaesthetic nursing interventions with respect to the agility and body orientation of the patients, and with respect to their interaction with the nurses. The observations were limited to the interventions washing, positioning, and mobilizing and lasted 20 to 60 minutes. During this time, an experienced nurse, who did not belong to the nursing team, completed a checklist. The checklist items comprise operationalized criteria of the kinaesthetic concept by Hatch and Maietta, as well as two questions directed to the patients. Body motion and orientation were judged by a 12-items scale, identical for observations prior to and immediately after the nursing intervention. The interaction between patients and nurses was judged by means of a 10-items scale. Group 1 (13 patients) was observed during conservative nursing; group 2 (another 13 patients) was observed almost half a year later during kinaesthetic nursing. All observations were recorded with the same instrument. There was a general positive effect of the nursing interventions. Kinaesthetic nursing, however, only showed a trend towards better effects on the patients' agility, body orientation or interaction abilities in comparison to conventional nursing. The results are discussed with respect to a recently published study on objective measurement of kinaesthetic nursing effects. There is a certain discrepancy between the well-known positive valuation of kinaesthetic nursing by the nurses themselves and the measurable effects of the method. This discrepancy cannot simply be explained by sample size, type of measurement, or the nurses'experience with the method.


Assuntos
Cinestesia , Neoplasias/enfermagem , Relações Enfermeiro-Paciente , Radioterapia/enfermagem , Idoso , Banhos/enfermagem , Competência Clínica , Deambulação Precoce/enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/radioterapia , Avaliação em Enfermagem , Registros de Enfermagem , Orientação , Satisfação do Paciente , Postura
18.
J Neuropathol Exp Neurol ; 61(7): 605-13, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12125739

RESUMO

We have previously shown that antioxidants such as a-phenyl-tert-butyl nitrone or N-acetylcysteine attenuate cortical neuronal injury in infant rats with bacterial meningitis, suggesting that oxidative alterations play an important role in this disease. However, the precise mechanism(s) by which antioxidants inhibit this injury remain(s) unclear. We therefore studied the extent and location of protein oxidation in the brain using various biochemical and immunochemical methods. In cortical parenchyma, a trend for increased protein carbonyls was not evident until 21 hours after infection and the activity of glutamine synthetase (another index of protein oxidation) remained unchanged. Consistent with these results, there was no evidence for oxidative alterations in the cortex by various immunohistochemical methods even in cortical lesions. In contrast, there was a marked increase in carbonyls, 4-hydroxynonenal protein adducts and manganese superoxide dismutase in the cerebral vasculature. Elevated lipid peroxidation was also observed in cerebrospinal fluid and occasionally in the hippocampus. All of these oxidative alterations were inhibited by treatment of infected animals with N-acetylcysteine or alpha-phenyl-tert-butyl nitrone. Because N-acetylcysteine does not readily cross the blood-brain barrier and has no effect on the loss of endogenous brain antioxidants, its neuroprotective effect is likely based on extraparenchymal action such as inhibition of vascular oxidative alterations.


Assuntos
Artérias Cerebrais/metabolismo , Cistina/análogos & derivados , Encefalite/metabolismo , Meningites Bacterianas/metabolismo , Degeneração Neural/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Streptococcus pneumoniae/patogenicidade , Oxirredutases do Álcool/metabolismo , Aldeídos/metabolismo , Animais , Antioxidantes/farmacologia , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/fisiopatologia , Óxidos N-Cíclicos , Cistina/farmacologia , Encefalite/tratamento farmacológico , Encefalite/fisiopatologia , Feminino , Sequestradores de Radicais Livres/farmacologia , Glutamato-Amônia Ligase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/fisiopatologia , Degeneração Neural/tratamento farmacológico , Degeneração Neural/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Óxidos de Nitrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Superóxido Dismutase/metabolismo
19.
Free Radic Biol Med ; 33(11): 1534-42, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12446211

RESUMO

Gamma-tocopherol (gammaT) complements alpha-tocopherol (alphaT) by trapping reactive nitrogen oxides to form a stable adduct, 5-nitro-gammaT [Christen et al., PNAS 94:3217-3222; 1997]. This observation led to the current investigation in which we studied the effects of gammaT supplementation on plasma and tissue vitamin C, vitamin E, and protein nitration before and after zymosan-induced acute peritonitis. Male Fischer 344 rats were fed for 4 weeks with either a normal chow diet with basal 32 mg alphaT/kg, or the same diet supplemented with approximately 90 mg d-gammaT/kg. Supplementation resulted in significantly higher levels of gammaT in plasma, liver, and kidney of control animals without affecting alphaT, total alphaT+gammaT or vitamin C. Intraperitoneal injection of zymosan caused a marked increase in 3-nitrotyrosine and a profound decline in vitamin C in all tissues examined. Supplementation with gammaT significantly inhibited protein nitration and ascorbate oxidation in the kidney, as indicated by the 29% and 56% reduction of kidney 3-nitrotyrosine and dehydroascorbate, respectively. Supplementation significantly attenuated inflammation-induced loss of vitamin C in the plasma (38%) and kidney (20%). Zymosan-treated animals had significantly higher plasma and tissue gammaT than nontreated pair-fed controls, and the elevation of gammaT was strongly accentuated by the supplementation. In contrast, alphaT did not significantly change in response to zymosan treatment. In untreated control animals, gammaT supplementation lowered basal levels of 3-nitrotyrosine in the kidney and buffered the starvation-induced changes in vitamin C in all tissues examined. Our study provides the first in vivo evidence that in rats with high basal amounts of alphaT, a moderate gammaT supplementation attenuates inflammation-mediated damage, and spares vitamin C during starvation-induced stress without affecting alphaT.


Assuntos
Ácido Ascórbico/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Tirosina/análogos & derivados , gama-Tocoferol/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Inflamação , Rim/efeitos dos fármacos , Masculino , Proteínas/metabolismo , Ratos , Ratos Endogâmicos F344 , Distribuição Tecidual , Tirosina/metabolismo , Vitamina E/metabolismo , Zimosan/farmacologia , alfa-Tocoferol/metabolismo
20.
Antivir Ther ; 9(1): 85-95, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15040540

RESUMO

OBJECTIVE: A high level of adherence to antiretroviral therapy is required for complete suppression of HIV replication, immunological and clinical effectiveness. We investigated whether cognitive behaviour therapy can improve medication adherence. DESIGN: Prospective randomized 1-year trial. SETTING: Collaboration of HIV university outpatient clinic and psychotherapists in private practice. PARTICIPANTS: 60 HIV-infected persons on stable antiretroviral combination therapy and viral load below 50 copies/ml. INTERVENTION: Cognitive behaviour intervention in individual patients, in addition to standard of care. MAIN OUTCOME MEASURES: Feasibility and acceptance of intervention; adherence to therapy assessed using medication event monitoring system (MEMS) and self-report questionnaire; virological failure; psychosocial measures. RESULTS: The median number of sessions for cognitive behaviour intervention per patient during the 1-year trial was 11 (range 2-25). At months 10-12, mean adherence to therapy as assessed using MEMS was 92.8% in the intervention and 88.9% in the control group (P=0.2); the proportion of patients with adherence > or = 95% was 70 and 50.0% (P=0.014), respectively. While there was no significant deterioration of adherence during the study in the intervention arm, adherence decreased by 8.7% per year (P=0.006) in the control arm. No differences between the intervention group and standard of care group were found regarding virological outcome. Compared with the control group, participants in the intervention group perceived a significant improvement of their mental health during the study period. CONCLUSIONS: Cognitive behavioural support in addition to standard of care of HIV-infected persons is feasible in routine practice, and can improve medication adherence and mental health.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Cognição/fisiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , HIV-1/isolamento & purificação , Cooperação do Paciente , Psicoterapia , Adulto , Idoso , Cognição/efeitos dos fármacos , Monitoramento de Medicamentos/psicologia , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/sangue , RNA Viral/isolamento & purificação , Inquéritos e Questionários , Fatores de Tempo , Carga Viral
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