Axonal transport of TREK and TRAAK potassium channels in rat sciatic nerves

The recent cloning, functional expression and brain localization of two new potassium channels, TREK and TRAAK, led us to examine whether both channels are present in peripheral nerves and can move along axons by means of axonal transport mechanisms. Using specific antibodies directed against TREK and TRAAK peptides, we found that immunoreactivity for both potassium channels accumulates above and below a ligature in rat sciatic nerves. The process was rapid and bidirectional suggesting that the channels are associated with vesicles. This represents the first report on the axonal transport of potassium channels.     

Synergistic antinociceptive interaction between acetaminophen or metamizol and B vitamins in the formalin test

There is evidence that B vitamins produce antinociception in animals. However, potentiation of NSAID‐induced antinociception by B vitamins is unclear. The current study was designed to investigate the antinociceptive interaction between a mixture of B vitamins and either acetaminophen or metamizol. Acetaminophen (56–316 mg/kg), metamizol (32–178 mg/kg), and the mixture of B vitamins (32–178 mg/kg of thiamine, pyridoxine, and cyanocobalamin in a 100:100:1 proportion, respectively) or a combination of each drug with the B vitamins mixture was administered orally to female Wistar rats, and the antinociceptive effect determined in the formalin test. Isobolographic analyses were used to define the nature of the interaction between NSAIDs and B vitamins. Oral administration of either drug produced a dose‐related antinociceptive effect. Isobolographic analyses revealed that both acetaminophen or metamizol and the B vitamins mixture interacted synergistically in the formalin test, suggesting that these two combinations could be useful in treating inflammatory pain states. Drug Dev. Res. 66:286–294, 2006. © 2006 Wiley‐Liss, Inc.     

Coxsackievirus-positive cervices in women with febrile illnesses during the third trimester in pregnancy

Coxsackievirus B5 infection was demonstrated in five of seven third-trimester pregnant women with undifferentiated febrile illnesses or aseptic meningitis. Coxsackievirus B5 was recovered from the cervix and throat in four women and from the rectum in three. No obvious illnesses were evident in the babies. These findings suggest that previously unrecognized cervical enterovirus carriage or infection is common in infected pregnant women in the last trimester and that subsequent neonatal infection at delivery may result.     

Experimental Tests and Numerical Simulations on the Ballistic Impact Response of a Highly Inhomogeneous Aluminium Foam

A sandwich structure is a composite material consisting of thin skins encapsulating a cellular core. Such structures have proven to be excellent energy absorbents and are frequently found in various types of protection. Even so, few studies exist in the open literature on the response of the core material itself under extreme loadings such as blast and impact. Since a blast load is usually accompanied by numerous fragments, it is important to understand and be able to predict the ballistic impact resistance of the often highly inhomogeneous cellular core materials in design. In this study, the ballistic impact response of an aluminium foam with a complex cell structure has been investigated both experimentally and numerically. First, an extensive material test program involving compression tests on cubic specimens loaded in the thickness direction of the foam was carried out to reveal the mechanical properties of the material. In addition, several of the specimens were scanned before testing using X-ray Micro Computed Tomography (XRMCT) to map the multi-scale topology and morphology of the material. These data were later analysed to extract density-variation plots in many different material orientations. Second, ballistic impact tests were conducted using a gas gun where rigid spheres were launched towards aluminium foam plates, and the ballistic limit velocity and curve of the foam material were established. Finally, numerical simulations of both the material tests and the ballistic impact tests were carried out using LS-DYNA and different modelling approaches based on the XRMCT data. It will be shown that, independent of the modelling strategy applied, good agreement between the experimental impact tests and the numerical predictions can be obtained. However, XRMCT data are important if the final goal is to numerically optimise and improve the behaviour of inhomogeneous foams with respect to energy absorption, thermal isolation, or similar properties.     

Cellular pharmacology of P-ethoxy antisense oligonucleotides targeted to Bcl-2 in a follicular lymphoma cell line

A P-ethoxy oligonucleotide (oligo), 20 bases long and specific for the translation initiation site of human Bcl-2 mRNA, was incorporated into liposomes to increase its intracellular delivery. This oligo selectively inhibited Bcl-2 protein expression and induced growth inhibition in t(14;18)-positive transformed follicular lymphoma (FL) cell lines. We studied the inhibitory effects of shorter liposomal P-ethoxy oligos (7, 9, 11 or 15 mer) in order to determine the activity of different oligo chain lengths targeted to the same Bcl-2 mRNA. At 12 μM, all the oligos inhibited the growth of a FL cell line. We compared the 7-mer oligo with the 20-mer oligo. The two oligos inhibited Bcl-2 protein expression similarly: 66% and 60% for the 7- and 20-mer, respectively. The uptake and retention of both oligos were also very similar. Our results indicate that the Bcl-2 inhibitory activity is maintained with P-ethoxy antisense oligos ranging from 7 to 20 bases.     

Análisis de los factores de influencia sobre el resultado de 500 ciclos de inseminación intrauterina homóloga

Objective

To evaluate the results and analyse different factors influencing pregnancy rate using homologous intrauterine insemination.

Subjects and methods

Retrospective analysis of 500 homologous intrauterine insemination cycles in 183 infertile couples. Only one insemination per stimulated ovarian cycle was performed in patients with: mild endometriosis, ovulatory factor, male subfertility or unexplained infertility. We studied female age, duration of infertility, stimulation protocol, number of cycle, number of preovulatory follicles, motile sperm count and endometrial thickness related to pregnancy rate.

Results

Pregnancy rate per couple was 24% and per intrauterine insemination 9%, 11% was multiple pregnancies. Best outcome has been got in women younger than 37 years (P=.048) and in cycles with more than one preovulatory follicle. Other studied factors did not have influence in homologous intrauterine insemination outcome.

Conclusions

Female age is a prognostic factor for homologous intrauterine insemination with poor outcome in women older than 38 years. Cycles with more than one preovolatory follicle have better outcome. No differences in pregnancy rate have been achieved with motile sperm count over 1.5 millions/0.3 ml.     

Corrosion Behavior of Al Modified with Zn in Chloride Solution

Aluminum-based alloys have been considered candidate materials for cathodic protection anodes. However, the Al-based alloys can form a layer of alumina, which is a drawback in a sacrificial anode. The anodes must exhibit uniform corrosion to achieve better performance. Aluminum can be alloyed with Zn to improve their performance. In this sense, in the present research, the electrochemical corrosion performance of Al-xZn alloys (x = 1.5, 3.5, and 5 at.% Zn) exposed to 3.5 wt.% NaCl for 24 h was evaluated. Polarization curves, linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS) were used to identify the electrochemical behavior. The microstructure of the samples before the corrosion assessment was characterized by means of X-ray diffraction analyses (XRD) and scanning electron microscopy (SEM). In addition, microstructures of the corroded surfaces were characterized using X-ray mappings via SEM. Polarization curves indicated that Zn additions changed the pseudo-passivation behavior from what pure Al exhibited in a uniform dissolution regime. Furthermore, the addition of Zn shifted the corrosion potential to the active side and increased the corrosion rate. This behavior was consistent with the proportional decrease in polarization resistance (R_p) and charge transfer resistance (R_ct) in the EIS. The analysis of EIS was done using a mathematical model related to an adsorption electrochemical mechanism. The adsorption of chloride at the Al-Zn alloy surface formed aluminum chloride intermediates, which controlled the rate of the process. The rate constants of the reactions of a proposed chemical mechanism were evaluated.     

Antioxidant,cytotoxic, and anti-venom activity of Alstonia parvifolia Merr. Bark

Objective: To evaluate antioxidant, cytotoxic, and anti-venom capacity of crude bark extracts of Alstonia parvifolia Merr. Methods: Gas chromatography-mass spec...