Electroacupuncture preconditioning alleviates myocardial ischemia-reperfusion injury through the hypothalamic paraventricular nucleus- interposed nucleus nerve pathway

OBJECTIVE

To explore whether the paraventricular nucleus (PVN) participates in regulation of the anti-myocardial ischemia-reperfusion injury (MIRI) effect of electroacupuncture (EA) and whether this is achieved through the PVN-interposed nucleus (IN) neural pathway.

METHODS

The modeling method of myocardial ischemia reperfusion injury was achieved by ligating the left anterior descending coronary artery in Sprague-Dawley rats. We used the Powerlab multi-channel physiological recorder system to record electro-cardiograms and analyze the changes in ST segment displacement; 2,3,5-Triphenyltetrazolium chloride staining was used to observe the percentage of myocardial infarction areas. Detecting cardiac troponin I (cTnI), lactate dehydrogenase (LDH) in serum was done with an enzyme-linked immunosorbent assay kit. Morphological changes in the myocardium were detected in each group with hematoxylin-eosin staining of paraffin sections. Detection of c-fos protein expression in the PVN of the hypothalamus was done with the immune-ofluorescence method. The Plexon multi-channel acquisition system recorded PVN neuron discharges and local field potentials in each group of rats. Offline Sorter software was used for cluster analysis. Neuro Explorer software was used to perform autocorrelation, raster and frequency characteristics and spectral energy analysis of neuron signals in each group.

RESULTS

Compared with the MIRI model group, the areas of myocardial infarction in the EA group were significantly reduced; the expression of cTnI, LDH in serum was decreased significantly. The firing frequency of pyramidal cells in the PVN was significantly increased and the spectrum energy map showed energy was reduced, c-fos expression in PVN was reduced, this indicated that neuronal activity in the PVN participates in the effect of EA improving myocardial injury. In addition, we used the kainic acid method to lesion the IN and observed that the effect of EA was weakened. For example, the area of myocardial infarction of lesion IN + EA group in rats was significantly increased compared with that resulting from EA group, the expression of cTnI, LDH in serum was significantly increased, the firing frequency of pyramidal cells in the PVN was significantly reduced. A spectral energy diagram shows that the energy after damage was higher than that of EA group. At the same time, the expression of c-fos in the PVN increased again.

CONCLUSION

Our results indicated that the PVN-IN nerve pathway may participate as an effective pathway of EA to improve the effect of myocardial injury.

Vitamin D deficiency in anesthesia department caregivers at the end of winter

BACKGROUND

To test whether the vitamin D status of anesthesia department caregivers practicing at high Northern latitudes is compatible with current recommendations, the 25-hydroxyvitamin D (25(OH)D) levels of caregivers at hospitals in Iceland (64°08' N) and in Wisconsin (43°07' N) were compared at the end of winter.

METHODS

Anesthesia department faculty and resident physicians, non-physician anesthetists, and critical care nurses completed a questionnaire, and provided blood samples for analysis of 25(OH)D by reverse-phase high performance liquid chromatography.

RESULTS

One hundred and six participants in Iceland and 124 participants in Wisconsin were enrolled. No difference in mean serum 25(OH)D levels between Iceland [70.53 nmol/l, standard deviation (SD) 30.87 nmol/l] and Wisconsin (70.0 nmol/l, SD 30.0 nmol/l) was observed. In Iceland and Wisconsin, 25(OH)D levels below 25 nmol/l were observed in 4.7% and 4.0%, below 50 nmol/l in 34.9% and 25.0%, and below 75 nmol/l in 56.6% and 61.3% of caregivers, respectively.

CONCLUSIONS

25(OH)D levels below the 50 nmol/l (20 ng/ml) threshold recommended by the Institute of Medicine and the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis, and below the 75 nmol/l (30 ng/ml) threshold recommended by The Endocrine Society, are highly prevalent among anesthesia caregivers working at two Northern hospitals at the end of winter who may otherwise not meet criteria to be tested. Anesthesia and critical care providers may wish to determine their 25(OH)D levels and use effective, safe, and low cost supplementation to target a 25(OH)D level compatible with optimal health.

Synthesis of a Substituted Phthalocyaninato-polysiloxane and its Langmuir-Blodgett Films

Tetrakis-4-(2,4-di-tert-amylphenoxy)phthalocyaninato-polysiloxane was synthesized. Its molecular structure was confirmed by elemental analysis, IR and UV-vis spectra. The gas-sensitive properties of its Langmuir–Blodgett films exposed to NH 3, I 2 and NO 2 in air were measured. The results showed that the detection sensitivity on exposure to NH3 in air can reach 0.1 ppm, while it can reach 100 ppm on exposure to NO 2 and I 2 in air.

AN EFFECTIVE ALGORITHM FOR INCOMPATIBILITY ABDUCTION PROBLEMS

In the last decade, abduction has been a very active research area. This results in a variety of models mechanizing abduction, namely within a probablistic or logical framework. Recently, a few abductive models have been proposed within a neural framework. Unfortunately, these neural-/probablistic-/logical-based models focus on the most simple class, called independent abduction problems. In this paper, we propose a neural-based model to deal with incompatibility abduction problems. To our knowledge, our model is the first one able to efficiently generate best explanations to the complex class of incompatibility abduction problems.