ABSTRACT
Objective and approach: In this study, we estimated the constant phase model (CPM) parameters from the respiratory impedance of male BALB/c mice by performing the forced oscillation technique (FOT) in a control group (n = 8) and in a murine model of asthma (OVA) (n = 10). Then, we compared the results obtained by two different methods, using a commercial equipment (flexiVent-flexiWare 7.X; SCIREQ, Montreal, Canada) (FXV) and a wavetube method equipment (Sly et al 2003 J. Appl. Physiol. 94 1460-6) (WVT). We believe that the results from different methods may not be comparable. First, we compared the results performing a two-way analysis of variance (ANOVA) for the resistance, elastance and tissue damping. MAIN RESULTS: We found statistically significant differences in all CPM parameters, except for resistance, when comparing Control and OVA groups. When comparing devices, we found statistically significant differences in resistance, while differences in elastance were not observed. For tissue damping, the results from WVT were observed to be higher than those from FXV. Finally, when comparing the relative variation between the CPM parameters of the Control and OVA groups in both devices, no significant differences were observed for all parameters. SIGNIFICANCE: We then conclude that this assessment can compensate the effect of using different cannulas. Furthermore, tissue damping differences between groups can be compensated, since bronchoconstrictors were not used. Therefore, we believe that relative variations in the results between groups can be a comparing parameter when using different equipment without bronchoconstrictor administration.
Subject(s)
Electric Impedance , Respiratory Mechanics , Animals , Asthma/physiopathology , Bronchoconstrictor Agents/pharmacology , Male , Mice , Mice, Inbred BALB C , Models, Biological , Respiratory Mechanics/drug effects , Signal Processing, Computer-AssistedABSTRACT
NAD metabolism regulates diverse biological processes, including ageing, circadian rhythm and axon survival. Axons depend on the activity of the central enzyme in NAD biosynthesis, nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2), for their maintenance and degenerate rapidly when this activity is lost. However, whether axon survival is regulated by the supply of NAD or by another action of this enzyme remains unclear. Here we show that the nucleotide precursor of NAD, nicotinamide mononucleotide (NMN), accumulates after nerve injury and promotes axon degeneration. Inhibitors of NMN-synthesising enzyme NAMPT confer robust morphological and functional protection of injured axons and synapses despite lowering NAD. Exogenous NMN abolishes this protection, suggesting that NMN accumulation within axons after NMNAT2 degradation could promote degeneration. Ectopic expression of NMN deamidase, a bacterial NMN-scavenging enzyme, prolongs survival of injured axons, providing genetic evidence to support such a mechanism. NMN rises prior to degeneration and both the NAMPT inhibitor FK866 and the axon protective protein Wld(S) prevent this rise. These data indicate that the mechanism by which NMNAT and the related Wld(S) protein promote axon survival is by limiting NMN accumulation. They indicate a novel physiological function for NMN in mammals and reveal an unexpected link between new strategies for cancer chemotherapy and the treatment of axonopathies.
Subject(s)
Axons/metabolism , Nerve Degeneration/metabolism , Nicotinamide Mononucleotide/metabolism , Peripheral Nerve Injuries/metabolism , Amidohydrolases/pharmacology , Animals , Axons/pathology , Bacterial Proteins/pharmacology , Mice , Nerve Degeneration/drug therapy , Nerve Degeneration/genetics , Nerve Degeneration/pathology , Nicotinamide-Nucleotide Adenylyltransferase/metabolism , Peripheral Nerve Injuries/drug therapy , Peripheral Nerve Injuries/genetics , Peripheral Nerve Injuries/pathologyABSTRACT
The construction of a wall-jet cell with amperometric detection using a set of disc electrodes whose radii ranged from 5 to 750 mum has been proposed. The influence of some experimental parameters like flow rate and electrode radius on hydrodynamic voltammograms recorded for a 0.5 mmol dm(-3) potassium ferrocyanide solution also containing 0.1 mol dm(-3) KCl has been discussed. Some considerations regarding the current signals obtained from flow injection experiments using both a 5- and a 750-mum radius platinum electrode were carried out in order to achieve the lowest limit of detection, a value of 0.03 mumol dm(-3) ferrocyanide being calculated by using the 5-mum radius microelectrode as amperometric detector. The wall-jet cell has been used in the determination of nitrite in saliva by quantifying the triiodide formed in the reaction of the analyte with excess iodide in acidic medium. A 12.5-mum platinum disc microelectrode maintained at +0.2 V vs. Ag/AgCl was used as amperometric detector. Peaks obtained in fiagrams after injection of diluted saliva to the carrier stream containing 0.1 mol dm(-3) sulphuric acid and 20 mmol dm(-3) potassium iodide were compared to an analytical curve obtained in the same conditions (r(2)=0.997) for a nitrite concentration in the range 1-10 mumol dm(-3). The concentration of nitrite in the saliva sample after the appropriate correction for dilution was found to be 2.3 ppm (0.05 mmol dm(-3)), in a good agreement with results obtained by using a standard spectrophotometric procedure (2.5 ppm). The limit of detection of the method was calculated as 0.2 mumol dm(-3), and the reproducibility was checked by measuring the peak current for 19 injections of 10 muM nitrite, the standard deviation being 3.7%.
ABSTRACT
Três grupos de voluntários, após assinatura de um termo de consentimento de participaçäo em experimento, foram submetidos a minucioso exame clínico e complementar de laboratório, bem como a uma entrevista, para se determinar qualquer alteraçäo física ou psíquica que fosse impeditiva de participaçäo no experimento. Receberam, respectivamente, por via oral, placebo, diazepam (5mg) ou Valmane (50mg), em intervalos de 8 horas aproxidamente, iniciando-se o tratamento no dia anterior ao teste, sendo a última dose administrada duas horas antes do procedimento de eliciaçäo de ansiedade, o Stroop-Color Word Test filmado (VRSCWT). A resposta de ansiedade eliciada pela situaçäo foi avaliada pelo Inventário de Ansiedade Traço-Estado de Spielberger. Os valores de ansiedade durante e após a situaçäo de teste, no grupo tratado com Valmane, näo diferiram dos valores-controle ou dos do grupo tratado com diazepam. Os resultados sugerem que o Valmane, na dose utilizada, apresenta, na situaçäo do teste de eliciaçäo de ansiedade, tendência a uma açäo semelhante ao do diazepam, apesar de menos potente. Os resultados mostraram ainda que o diazepam foi eficaz em impedir o aumento de ansiedade eliciado pela situaçäo de teste
Subject(s)
Humans , Male , Female , Adult , Anxiety/chemically induced , Valerian , Clinical Trials as Topic , Plant Extracts/therapeutic use , Stress, Psychological , Test Anxiety ScaleABSTRACT
During 12 years, we have effected 6,982 electroshocks with anesthesia and celocurine (N.D.) on 713 patients, i.e. 7.25% of the total hospitalized patients. 62% of them (440) were all this time under antidepressant drugs and 38% (273) were not. We observed 16 minor incidents ten (2.27%) among those under treatment and six (2.19%) among the others; of these 16 incidents, 11 led to an interruption of the treatment for safety. The association of antidepressant drugs with electroshock under anesthesia and celocurine (N.D.) does not present any real danger.
