Predicted values were compared
with respective experimental results. In all cases, a fair agreement between experimental findings and theoretical predictions was found. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124: 67-76,2012″
“The irreversible transformation of androgens into oestrogens is catalysed by ecytochrome P450 aromatase. In the present study, we explored the contribution of the (TTTA)(n) polymorphism in the aromatase gene (CYP19) to sperm concentration and motility. Ninety normozoospermic and 60 oligospermic men were examined during infertility examinations. DNA was extracted from spermatozoa, and the CYP19 (TTTA)(n) polymorphism Selleckchem VX 770 was genotyped by PCR. Genotype analysis revealed six CYP19(TTTA)(n) alleles with 7-12 repeats. The allelic distribution of the CYP19 (TTTA)(n) polymorphism differed between normozoospermic and oligospermic men (P < 0.01). Oligospermic men less frequently had long CYP19 alleles than did normozoospermic men (25 and 37.8%, respectively; P, 0.02). The higher frequency of short CYP19 alleles in oligospermic men compared to normozoospermic men (43.3
and 28.3%, respectively; P < 0.01) was primarily due to the distribution of the CYP19 (TTTA)(7) allele. The CYP19 (TTTA)(7) allele was associated with lower sperm concentration in normozoospermic men (P < Selleckchem PP2 0.01) and in the total study population (P < 0.01); it was also associated with lower sperm motility in normozoospermic men (P < 0.05) and in the total study population (P < 0.01). In conclusion, the CYP19 (TTTA)(7) allele probably impairs aromatase activity, which in turn alters aromatase and oestrogen levels in the testis, leading to
decreased sperm concentration and motility. These findings support the significance of cytochrome P450 aromatase in human spermatogenesis and consequently in semen quality. Asian Journal of Andrology (2011) 13, 292-297; doi:10.1038/aja.2010.144; published online 10 January 2011″
“The piezoelectric and ferroelectric properties of microscopically poled poly(vinylidene fluoride trifluoroethylene) [P(VDF-TrFE)] copolymer films have been examined at different temperatures approaching this website Curie point using piezoresponse force microscopy in combination with dual frequency resonance tracking technique, with the amplitude, phase, quality factor, and resonance frequency of the piezoresponse simultaneously quantitatively determined. It is observed that the piezoresponse remains relatively stable up to 110 degrees C, and then drops rapidly to zero. The variations of the quality factor and resonance frequency with respect to the temperature change are also observed, which is consistent with thermal induced softening in films.