Hyperthyroidism modifies ecto-nucleotidase activities in synaptosomes from hippocampus and cerebral cortex of rats in different phases of development

Here we investigate the possible effects of the hyperthyroidism on the hydrolysis of the ATP to adenosine in the synaptosomes of hippocampus, cerebral cortex and blood serum of rats in different developmental phases. Manifestations of hyperthyroidism include anxiety, nervousness, tachycardia, physical hyperactivity and weight loss amongst others. The thyroid hormones modulate a number of physiological functions in central nervous system, including development, function, expression of adenosine A(1) receptors and transport of neuromodulator adenosine. Thus, hyperthyroidism was induced in male Wistar rats (5-, 60-, 150- and 330-day old) by daily injections of L-thyroxine (T4) for 14 days. Nucleotide hydrolysis was decreased by about 14-52% in both hippocampus and cerebral cortex in 5 to 60-day-old rats. These changes were also observed in rat blood serum. In addition, in 11-month-old rats, inhibition of ADP and AMP hydrolysis persisted in the hippocampus, whereas, in cerebral cortex, an increase in AMP hydrolysis was detected. Thus, hyperthyroidism affects the extracellular nucleotides balance and adenosine production, interfering in neurotransmitter release, development and others physiological processes in different systems.     

Intense pulsed light in the treatment of non‐aesthetic facial and neck vascular lesions: report of 85 cases

Background Intense pulsed light (IPL) treatment is one of the most effective procedures for patients with non‐aesthetic vascular lesions in addition to signs of skin photoageing, and it has been reported as very successful in the treatment of telangiectasias, spider nevi, erythrosis, and above all, rosacea and poikiloderma. Its use is based on the principle of selective photothermolysis, which exploits the haemoglobin absorption peak among its range of wavelengths. Objective The aim of this study is to assess the efficacy and safety of intense pulsed light in treating non‐aesthetic vascular skin lesions, especially with regard to poikiloderma of Civatte and rosacea. Methods A total of eighty‐five patients, 64 women and 21 men, with 63 non‐aesthetic vascular lesions (28 Poikiloderma of Civatte and 35 rosacea), 22 pigmented lesions (UV‐related hyperpigmentation of solar lentigo‐type) and four precancerous lesions (actinic keratosis, AKs), were treated repeatedly with IPL for 2 years. The patients received a mean of five treatments (range 4–6) at 3‐weekly intervals. They were evaluated via clinical observations and professional photographs were taken before each treatment and after 2 weeks, 4 weeks, 3 months, 6 months and 12 months. The outcome of the IPL treatments was evaluated by four independent dermatologists, who were not informed about the study protocol, and who assessed the performance of IPL by dividing the results into four categories: no results, slight improvement, moderate improvement and marked improvement. Results All the patients showed improvements in their overall lesions: 72 lesions (80.9%) achieved a marked improvement, 14 lesions (15.7%) achieved a moderate improvement and three lesions (3.4%) achieved a slight improvement. The results of the 63 non‐aesthetic vascular lesions in Rosacea and Poikiloderma of Civatte were: 51 with a marked improvement, 10 with moderate improvement, whereas only two lesions achieved a slight improvement. The improvement of all four actinic keratoses was marked whereas the 22 pigmented lesions obtained a marked improvement in 17 cases, a moderate improvement in four cases and a slight improvement in one case. No undesirable effects were observed. Conclusions Our study confirms how by minimizing side‐effects, time and costs, IPL can be effective and safe for the treatment of non‐aesthetic facial and neck vascular lesions.     

Quantized Control Design for Coupled Dynamic Networks with Communication Constraints

This paper is concerned with the quantized synchronization control problem of coupled dynamic networks (CDNs) with communication constraints. The networked-induced delay, data packet dropouts, and signal quantization effects are simultaneously considered in the synchronization controller design. A new closed-loop coupled dynamic system is constructed, where both the interval time-varying delays and quantized parameters are taken into account. By using Kronecker product technique and the Lyapunov–Krasovskii functional approach, a stability criterion is obtained for the closed-loop CDNs, which also guarantees that the CDNs are synchronized. Then, both the networked controller and the quantized parameters can be designed. Finally, a simulation example is given to illustrate the effectiveness of the proposed method.     

Reliability of mechanical and phased-array designs for serial intravascular ultrasound examinations

Background: Both mechanical and multi-element intravascular ultrasound designs have potential advantages and limitations that may impact on their value for clinical and research purposes. Determination of the reproducibility of measurements is critical before a given system can be used in studies such as regression of atherosclerosis trials. Methods: We performed serial intravascular ultrasound imaging with catheters using mechanical and phased-array designs in stented and non-stented coronary arteries in dogs and in patients. Results: Both systems correlated well for areas (r ≥ 0.90, p < 0.0001) and diameters (r ≥ 0.84, p < 0.0001) in dogs and in patients. There was a slight difference between multi-element and mechanical designs for measurements of area (mean difference in dogs and in patients: ?0.24 and 0.96 mm², p < 0.055) and diameter (?0.08 and 0.16 mm, p < 0.0001). The reproducibility of the multi-element system for reanalysis of the same frames and for analysis of serial pullbacks was similar to the same measurements with the mechanical system (r ≥ 0.96 for all measurements). The differences in absolute and relative variability between the mechanical and phased-array designs, both for reanalysis of same frames and serial pullbacks, were very small. Conclusions: Although multi-element and mechanical intravascular ultrasound designs are not strictly interchangeable, their similar reproducibility and the small differences in measurements demonstrate that both designs are acceptable alternatives for trials of regression of atherosclerosis. Determination of the variability for serial pullbacks of both designs was also important to assess the statistical power of such trials.     

Effect of nitric oxide donors on extracellular ATP, ADP, and AMP catabolism in rat hippocampal synaptosomes

Extracellular adenine nucleotides acting as signaling molecules are inactivated by hydrolysis catalyzed by ectonucleotidases. Adenosine triphosphate (ATP) diphosphohydrolase (apyrase, EC 3.6.1.5) and 5'-nucleotidase (EC 3.1.3.5) are involved in an enzymatic chain for the hydrolysis of ATP to adenosine in the synaptic cleft. In this study, we investigated the in vitro effect of nitric oxide (NO) donors on extracellular ATP, adenosine diphosphate (ADP), and adenosine monophosphate (AMP) catabolism in hippocampal synaptosomes of rats. We evaluated the effect of the incubation time on ATP, ADP, and AMP hydrolysis in the absence and in the presence of 1 mM sodium nitroprusside (SNP). The inhibitory effect of SNP increased with the incubation time and the maximal inhibition was observed after 180 min for both enzyme activities. The inhibition observed attained a maximum at 1 mM SNP for ATP, ADP, and AMP hydrolysis, with the enzyme activities being markedly reduced at this concentration of SNP. However, other NO donors tested, such as S-nitroso-N-acetyl-penicillamine and isosorbide dinitrate, did not affect the enzyme activities. The effect of the NO donor, SNP, on extracellular ATP and ADP catabolism was increased by the addition of the thiol glutathione but this effect was not observed on extracellular AMP catabolism. The results suggest that the increased production of NO could have a modulatory role on the ectonucleotidase activities.