Best practice for PTEN gene and protein assessment in anatomic pathology

There is a lack of standardization of a best practice protocol for Phosphatase and Tensin Homolog (PTEN) assessment by immunohistochemistry in anatomic pathology routine practice. We performed immunohistochemistry for 19 antibodies against PTEN, eleven of which were excluded during the standardization step. Immunohistochemistry of the remaining eight antibodies was performed on a Tissue Microarray containing 55 prostate and 40 renal carcinoma samples. Fluorescent in situ hybridization (FISH) was used as reference standard for immunohistochemistry specificity evaluation. Concerning nuclear staining, polyclonal (Cat#22034-1-AP); 6H2.1 mMAb (Cat#ABM-2052), Y184 RabMAb (Cat#NB110-57441) and 217702 mMAb antibodies presented the highest agreement with fluorescent in situ hybridization (p < 0.001 for all) and with regard to cytoplasmic staining, Y184 RabMAb (Cat#NB110-57441); polyclonal (Cat#22034-1-AP) and 217702 mMAb presented the highest agreement (p < 0.001 for all). Our results indicate that several commercially available antibodies do not show reliability of sensitivity and specificity for PTEN evaluation and we propose 6H2.1 mMAb (Cat#ABM-2052) as the antibody of choice for laboratory standardization and best practice in clinical routine, which demonstrated excellent sensitivity for both nuclear and cytoplasmic staining, specificity for PTEN by Western blot and good correlation with PTEN status by FISH with regard to nuclear staining.     

Dispersion of γ-Alumina Nano-Sized Spherical Particles in a Calamitic Liquid Crystal. Study and Optimization of the Confinement Effects

We report an experimental study on confined systems formed by butyloxybenzylidene octylaniline liquid crystal (4O.8) + γ-alumina nanoparticles. The effects of the confinement in the thermal and dielectric properties of the liquid crystal under different densities of nanoparticles is analyzed by means of high resolution Modulated Differential Scanning Calorimetry (MDSC) and broadband dielectric spectroscopy. First, a drastic depression of the N-I and SmA-N transition temperatures is observed with confinement, the more concentration of nanoparticles the deeper this depression is, driving the nematic range closer to the room temperature. An interesting experimental law is found for both transition temperatures. Second, the change in shape of the heat capacity peaks is quantified by means of the full width half maximum (FWHM). Third, the confinement does not noticeably affect the molecular dynamics. Finally, the combination of nanoparticles and the external applied electric field tends to favor the alignment of the molecules in metallic cells. All these results indicate that the confinement of liquid crystals by means of γ-alumina nanoparticles could be optimum for liquid crystal-based electrooptic devices.     

Muscle endothelial-dependent microvascular dysfunction in adulthood due to early postnatal overnutrition

The aims of our study were to investigate effects of postnatal overnutrition, obtained by restricting the number of pups per litter, on microcirculatory reactivity, fat depots, its total percentage and lipid profile. Microvascular reactivity was evaluated in the cremaster muscle of 24 hamsters divided into four groups, with 6 animals in each one: normal (NL) and restricted (RL) litter groups, both at 6th and 21st weeks of age. The NL group had 8-9 pups and the RL 3 pups per litter and to avoid the litter effect, only one animal was used per litter. The results have shown that the RL group had higher velocity of weight, body mass and fat gain compared to the NL one at weeks 6 and 21. Significant differences were also observed on urogenital fat depot, total cholesterol and low density lipoprotein between groups. At the lowest concentration of Ach, the RL group showed smaller arteriolar dilatation at the 21st than at the 6th week [5(3-13) vs 19(8-40)%, p<0.01] while the NL one did not show any difference within the group. The highest concentration of Ach at the 21th week pointed to endothelial-dependent microvascular dysfunction in RL compared to NL [3(8-26) vs. 13(8-26)%, p<0.05]. Endothelial-independent microvascular reactivity was similar between groups. Our data suggest that postnatal overnutrition is associated to muscle endothelial-dependent microvascular dysfunction, greater body mass and total percentage of fat and impaired the lipid profile. In conclusion, the imprinting promoted by this experimental model of obesity was able to influence microvascular reactivity later in life.     

Long-term training induces a healthy inflammatory and endocrine emergent biomarker profile in elderly men

The objective of the present study was to investigate the changes in a large panel of emergent geriatric biomarkers in long-term trained elderly men to analyze the effects of long-term exercise on an aged population. We collected blood samples from two groups of male volunteers older than 65 years who maintain a measure of functional independence: one group of sedentary subjects without a history of regular physical activity and the other of subjects who have sustained training, starting during adulthood (mean training time = 49 ± 8 years). We studied morbidity, polypharmacy, cellular and serological inflammatory parameters, and endocrine mediators. After adjusting for confounding factors, we observed reduced medication intake per subject and lower number of diseases per subject with statistical differences nearly significant in the long-term exercise group. We showed that long-term training was associated with lower levels of white blood cell counts, neutrophil counts, interleukin-6, interleukin-10, interleukin-1 receptor antagonist, and soluble TNF receptor-I. Furthermore, we noted an increase in the concentrations of insulin-like growth factor-1 and dehydroepiandrosterone in the long-term training group. We concluded that long-term exercise training from adulthood to old age is clearly associated with a healthy profile of emergent geriatric biomarkers. Long-term training could improve the inflammatory–endocrine imbalance associated with disease, frailty, functional decline, and mortality in elderly men. Our results point to the benefits of prolonged exercise from adulthood to old age.     

Analysis of the effects of irradiation in osseointegrated dental implants

Objective: The purpose of the present study was to evaluate the influence of radiation in osseointegrated dental implants installed in tibiae of rats. Material and methods: Screw‐shaped implants (2.5 mm diameter by 3.5 mm length) were custom made from commercially pure titanium bars. Titanium implants were blasted and sterilized before implantation. Animals were divided into two groups of 12 animals each and the rats were not paired after the groups' formation. The experimental group (group 1) received external irradiation 4 weeks after surgery while in the control group (group 2) animals were kept free of radiation. The shear strength required to detach the implant from bone was measured by push‐out testing and osseointegration was histologically evaluated. Results: Results showed that the compressive strength of irradiated implants (33.49 MPa) was significantly lower than the compressive strength of non‐irradiated implants (48.05 MPa). Conclusions: We concluded that the mechanical strength bonding between implants and host tissues decreased after irradiation. To cite this article:
Oliveira JAG, Escada ALA, Alves Rezende MCR, Mathor MB, Alves Claro APR. Analysis of the effects of irradiation in osseointegrated dental implants.
Clin. Oral Impl. Res. 23 , 2012 511–514.
doi: 10.1111/j.1600‐0501.2010.02149.x     

Methylparaben concentration in commercial Brazilian local anesthetics solutions

Objective

To detect the presence and concentration of methylparaben in cartridges of commercial Brazilian local anesthetics.

Material and methods

Twelve commercial brands (4 in glass and 8 in plastic cartridges) of local anesthetic solutions for use in dentistry were purchased from the Brazilian market and analyzed. Different lots of the commercial brands were obtained in different Brazilian cities (Piracicaba, Campinas and São Paulo). Separation was performed using high performance liquid chromatography (HPLC) with UV-Vis detector. The mobile phase used was acetonitrile:water (75:25 - v/v), pH 4.5, adjusted with acetic acid at a flow rate of 1.0 ml.min^-1.

Results

When detected in the solutions, the methylparaben concentration ranged from 0.01% (m/v) to 0.16% (m/v). One glass and all plastic cartridges presented methylparaben.

Conclusion

1. Methylparaben concentration varied among solutions from different manufacturers, and it was not indicated in the drug package inserts; 2. Since the presence of methylparaben in dental anesthetics is not regulated by the Brazilian National Health Surveillance Agency (ANVISA) and this substance could cause allergic reactions, it is important to alert dentists about its possible presence.