Associations between stressors and difficulty sleeping in critically ill patients admitted to the intensive care unit: a cohort study.

BACKGROUND: Patients admitted to the intensive care unit (ICU) experience sleep disruption caused by a variety of conditions, such as staff activities, alarms on monitors, and overall noise. In this study, we explored the relationship between noise and other factors associated with poor sleep quality in patients. METHODS: This was a prospective cohort study. We used the Richards-Campbell Sleep Questionnaire to explore sleep quality in a sample of patients admitted to the ICU of a private hospital. We measured the noise levels within each ICU three times a day. After each night during their ICU stay, patients were asked to complete a survey about sleep disturbances. These disturbances were classified as biological (such as anxiety or pain) and environmental factors (such as lighting and ICU noise). RESULTS: We interviewed 71 patients; 62% were men (mean age 54.46 years) and the mean length of stay was 8 days. Biological factors affected 36% and environmental factors affected 20% of the patients. The most common biological factor was anxiety symptoms, which affected 28% of the patients, and the most common environmental factor was noise, which affected 32.4%. The overall mean recorded noise level was 62.45 dB. Based on the patients' responses, the environmental factors had a larger effect on patients' sleep quality than biological factors. Patients who stayed more than 5 days reported less sleep disturbance. Patients younger than 55 years were more affected by environmental and biological factors than were those older than 55 years. CONCLUSIONS: Patient quality of sleep in the ICU is associated with environmental factors such as noise and artificial lighting, as well as biological factors related to anxiety and pain. The noise level in the ICU is twice that recommended by international guides. Given the stronger influence of environmental factors, the use of earplugs or sleeping masks is recommended. The longer the hospital stay, the less these factors seem to affect patients' sleep quality.

Molecular detection of Bartonella, Ehrlichia and Mycoplasma in feral dogs of El Pedregal de San Angel Ecological Reserve in Mexico City / Detecção molecular de Bartonella, Ehrlichia e Mycoplasma em cães selvagens da Reserva Ecológica El Pedregal de San Angel, na Cidade do México

Abstract Free-ranging and feral dogs represent a group of unattended companion animals. They impact wild animal populations by predating native species, displacing predators and introducing exotic pathogens. The aim of this work was to describe the molecular occurrence of Rickettsia, Ehrlichia, Anaplasma, Mycoplasma and Bartonella in feral dogs. The study was carried out in the last relict of a protected area in Mexico City. Blood clots samples from 19 dogs were obtained and analyzed for detection of specific fragments of the 16S-rRNA gene for Anaplasma, Ehrlichia and Mycoplasma and citrate synthase (gltA) for Bartonella and Rickettsia. Our results showed that DNA from three bacteria species (Bartonella vinsonii subsp. berkhoffii, Ehrlichia canis and Mycoplasma haemocanis) was present with frequencies ranging from 5.3 to 15.8%. This is the first record of B. vinsonii subsp. berkhoffii and M. haemocanis in dogs from México, and also the first finding of Ehrlichia canis in Mexico City. It is important to perform surveillance of feral dog populations in order to identify the impact of these pathogens on wild animal populations and Public Health in order to establish prevention and protection programs.

Resumo Cães errantes e selvagens representam um grupo de animais de companhia livres. Eles impactam as populações de animais selvagens pela predação de espécies nativas, deslocando predadores e introduzindo patógenos exóticos. O objetivo deste trabalho foi descrever a ocorrência molecular de Rickettsia, Ehrlichia, Anaplasma, Mycoplasma e Bartonella em cães selvagens. O estudo foi realizado no último ecossistema de uma área protegida na Cidade do México. Amostras de coágulos sanguíneos de 19 cães foram obtidas e analisadas para detecção de fragmentos específicos do gene 16S-rRNA para Anaplasma, Ehrlichia e Mycoplasma e citrato sintase (gltA) para Bartonella e Rickettsia. Nossos resultados mostraram que o DNA de três espécies de bactérias (Bartonella vinsonii subsp. berkhoffii, Ehrlichia canis e Mycoplasma haemocanis) estava presente com frequências variando de 5,3 a 15,8%. Este é o primeiro registro de B. vinsonii subsp. berkhoffii e M. haemocanis em cães do México, e também a primeira descrição de Ehrlichia canis na Cidade do México. É importante realizar a vigilância das populações de cães selvagens para identificar o impacto desses patógenos nas populações de animais silvestres e na Saúde Pública, a fim de estabelecer programas de prevenção e proteção.

Molecular detection of Bartonella, Ehrlichia and Mycoplasma in feral dogs of El Pedregal de San Angel Ecological Reserve in Mexico City.

Free-ranging and feral dogs represent a group of unattended companion animals. They impact wild animal populations by predating native species, displacing predators and introducing exotic pathogens. The aim of this work was to describe the molecular occurrence of Rickettsia, Ehrlichia, Anaplasma, Mycoplasma and Bartonella in feral dogs. The study was carried out in the last relict of a protected area in Mexico City. Blood clots samples from 19 dogs were obtained and analyzed for detection of specific fragments of the 16S-rRNA gene for Anaplasma, Ehrlichia and Mycoplasma and citrate synthase (gltA) for Bartonella and Rickettsia. Our results showed that DNA from three bacteria species (Bartonella vinsonii subsp. berkhoffii, Ehrlichia canis and Mycoplasma haemocanis) was present with frequencies ranging from 5.3 to 15.8%. This is the first record of B. vinsonii subsp. berkhoffii and M. haemocanis in dogs from México, and also the first finding of Ehrlichia canis in Mexico City. It is important to perform surveillance of feral dog populations in order to identify the impact of these pathogens on wild animal populations and Public Health in order to establish prevention and protection programs.

Synthesis and antioxidant activity of nitrohydroxytyrosol and its acyl derivatives.

A series of nitroderivatives has been synthesized from hydroxytyrosol, the natural olive oil phenol, to increase the assortment of compounds with putative effects against Parkinson's disease. Nitrohydroxytyrosyl esters were obtained from nitrohydroxytyrosol using a chemoselective one-step, high-yield, transesterification procedure. The antioxidant activity of these new series of nitrocatechols was evaluated using FRAP, ABTS, and ORAC assays and compared to that of free hydroxytyrosol. The nitro functional group induced a significant increase in the antioxidant activity of nitrohydroxytyrosol compared to hydroxytyrosol. Regarding nitroester derivatives, variable antioxidant activity was observed depending on the acyl side-chain length; shorter chains maintained or even enhanced the antioxidant activity compared to nitrohydroxytyrosol, decreasing the activity with longer side chains in keeping with their lipophilic nature. Therefore, it may be concluded that nitroester derivatives of hydroxytyrosol, which may be obtained by a simple, high-yield reaction, have elevated antioxidant activity and thus present potential bioactivity.

Hydroxytyrosol induces antioxidant/detoxificant enzymes and Nrf2 translocation via extracellular regulated kinases and phosphatidylinositol-3-kinase/protein kinase B pathways in HepG2 cells.

Hydroxytyrosol (HTy) is a natural polyphenol abundant in olive oil, which possesses multiple biological actions. Particularly, HTy has cytoprotective activity against oxidative-stress-induced cell damage, but the underlying mechanisms of action remain unclear. Here, we have investigated the molecular mechanism involved in the protection exerted by HTy on tert-butyl hydroperoxide-induced damage in human HepG2 liver cells. Treatment of HepG2 cells with HTy increased the expression and the activity of glutathione-related enzymes such as glutathione peroxidase, glutathione reductase and glutathione S-transferase. HTy also induced the nuclear transcription factor erythroid 2p45-related factor (Nrf2), a transcription factor implicated in the expression of several antioxidant/detoxificant enzymes. Moreover, two important signalling proteins involved in Nrf2 translocation, the protein kinase B and the extracellular regulated kinases, were also activated by HTy. Further studies with specific inhibitors confirmed that both molecular pathways are critical for the nuclear translocation of Nrf2, the increased enzyme expression and activity and the beneficial effect against oxidative stress induced by HTy. In conclusion, together with the inherent radical scavenging activity of HTy, our results provide an additional mechanism of action to prevent oxidative stress damage through the modulation of signalling pathways involved in antioxidant/detoxifying enzymes regulation.

Synthesis of hydroxytyrosyl alkyl ethers from olive oil waste waters.

The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydroxytyrosol.

New lipophilic tyrosyl esters. Comparative antioxidant evaluation with hydroxytyrosyl esters.

New lipophilic esters of tyrosol, a naturally occurring phenol with interesting biological properties, have been synthesized in good yields by a chemoselective procedure, using lipase from Candida antarctica or p-toluenesulfonic acid as catalysts. Their antioxidant activities have been evaluated by the Rancimat test in lipophilic food matrices, as well as by FRAP and ABTS assays in methanolic solutions, and compared with those of previously synthesized hydroxytyrosyl esters. Free tyrosol, hydroxytyrosol, butylhydroxytoluene, and alpha-tocopherol were used as standards. All methods used for the antioxidant activity evaluation emphasized the high influence of the ortho-diphenolic structure on the antioxidant capacity, tyrosol and its derivatives being less active than hydroxytyrosol and its analogues and even less than BHT and alpha-tocopherol. In addition, the Rancimat test revealed a lower activity for ester derivatives than for their respective reference compounds (HTy or Ty), in agreement with the polar paradox. On the other hand, FRAP and ABTS methods reported an opposite behavior between the synthetic esters and their respective references. Thus, hydroxytyrosyl esters were more active than HTy, whereas tyrosyl esters were less active than Ty. The length and nature of the acyl side chain did not seem to play an important role in the antioxidant activity of either the hydroxytyrosyl or tyrosyl ester series, since no significant differences were observed among them.

Neuroprotective effect of hydroxytyrosol and hydroxytyrosol acetate in rat brain slices subjected to hypoxia-reoxygenation.

Hydroxytyrosol (HT) and hydroxytyrosol acetate (HT-AC) are two well-known phenolic compounds with antioxidant properties that are present in virgin olive oil (VOO). Because VOO has shown neuroprotective effects in rats, the purpose of the present study was to investigate the possible neuroprotective effect of HT and HT-AC in a model of hypoxia-reoxygenation in rat brain slices after in vitro incubation of these compounds or after 7 days of oral treatment with 5 or 10 mg/kg per day. Lactate dehydrogenase (LDH) efflux to the incubation medium was measured as a marker of brain cell death. HT and HT-AC inhibited LDH efflux in a concentration-dependent manner, with 50% inhibitory concentrations of 77.78 and 28.18 microM, respectively. Other well-known antioxidants such as vitamin E and N-acetyl-cysteine had no neuroprotective effect in this experimental model. After 1 week of treatment, HT (5 and 10 mg/kg per day p.o.) reduced LDH efflux by 37.8% and 52.7%, respectively, and HT-AC reduced LDH efflux by 45.4% and 67.8%. These data are additional evidence of the cytoprotective effect of VOO administration, and provide a preliminary basis for further study of these polyphenols as potential neuroprotective compounds.

Effects of hydroxytyrosol and hydroxytyrosol acetate administration to rats on platelet function compared to acetylsalicylic acid.

Virgin olive oil (VOO) contains the polyphenols hydroxytyrosol (HT) and hydroxytyrosol acetate (HT-AC). This study investigated the antiplatelet effect of HT and HT-AC in healthy rats and compared their effects to acetylsalicylic acid (ASA). All compounds were administered orally for 7 days. HT and HT-AC inhibited platelet aggregation in whole blood, with a 50% inhibitory dose (ID50) of 48.25 mg/kg per day for HT, 16.05 mg/kg per day for HT-AC, and 2.42 mg/kg per day for ASA. Platelet synthesis of thromboxane B2 was inhibited by up to 30% by HT and 37% by HT-AC; the ID50 of this effect for ASA was 1.09 mg/kg per day. Vascular prostacyclin production was inhibited by up to 27.5% by HT and 32% by HT-AC; the ID50 of this effect for ASA was 6.75 mg/kg per day. Vascular nitric oxide production was increased by up to 34.2% by HT, 66% by HT-AC, and 64% by ASA. We conclude that HT and HT-AC administered orally inhibited platelet aggregation in rats and that a decrease in thromboxane synthesis along with an increase in nitric oxide production contributed to this effect.

Lipophilic hydroxytyrosyl esters. Antioxidant activity in lipid matrices and biological systems.

Antioxidant activities of lipophilic hydroxytyrosyl acetate, palmitate, oleate, and linoleate were compared with those of hydroxytyrosol, alpha-tocopherol, and butylhydroxytoluene (BHT) in both glyceridic matrix and biological systems. Aliquots of a glyceridic matrix spiked with various concentrations of antioxidant were subjected to accelerated oxidation in a Rancimat apparatus operated at 90 degrees C. The relationships between induction time (IT) and antioxidant concentration (mmol/kg) presented by hydroxytyrosol and hydroxytyrosyl acetate, palmitate, oleate, and linoleate were similar. Hydroxytyrosol and its esters showed greater antioxidant activity than alpha-tocopherol or BHT. We also evaluated the capacity of hydroxytyrosyl esters to protect proteins and lipids against oxidation caused by peroxyl radicals, using a brain homogenate as an ex vivo model. All tested compounds showed a protective effect in these systems, which was greater in preventing the generation of carbonyl groups in protein than of malondialdehyde in lipid. Inclusion of a lipophilic chain in the hydroxytyrosol molecule enhanced its antioxidant capacities in this biological model.

Relationships between oxidative stability, triacylglycerol composition, and antioxidant content in olive oil matrices.

In olive oils, relationships between oxidative stability, glyceridic composition, and antioxidant content were investigated. Lipid matrices, obtained by purification of olive and high-oleic sunflower oils, were spiked with hydroxytyrosol, alpha-tocopherol, and mixtures of them and then subjected to oxidation in a Rancimat apparatus at 100 degrees C. At the same concentration of antioxidants, induction time (IT) decreased as the unsaturation rate of the matrix increased, but only fair correlations were found with fatty acid composition. Oxidative susceptibility (OS(TAG)) was calculated as a function of the relative oxidation rate of the triacylglycerols, and a linear relationship-IT (h) = (a + b)OS(TAG)-between induction time and this parameter showed a good correlation coefficient (r > 0.990, p < 0.001). In the case of matrices with a single antioxidant, origin ordinate (a) and slope (b) can be calculated as a function of the antioxidant concentration. In matrices spiked with mixtures of hydroxytyrosol and alpha-tocopherol, a simple relationship between the coefficients a and b and the concentration of antioxidants cannot be established because additive and subtractive effects occur depending on the relative concentrations of both antioxidants. However, approximate values for these coefficients can be obtained, allowing the estimation of the oil stability. In various olive oils, an acceptable agreement was found between the IT experimentally determined and that calculated from the oil composition. These results confirmed that the Rancimat stability of olive oils mainly depends on triacylglycerol composition and concentrations of o-diphenols and alpha-tocopherol.