Materials Characterization Techniques, by S. Zhang, L. Li and A. Kumar. Boca Raton, CRC Press, 2009. 328pp. ISBN-13: 978-1-4200-4294-8, ISBN-10: 1-4200-4294-7

A M. domestica strain highly resistant to pyriproxyfen, a juvenile hormone analogue, was established by laboratory selection of flies collected from the 3rd Yumenoshima dumping-island in Tokyo Bay, Japan, during 1987. The strain developed 4900-foldre%sistance to pyriproxyfen in the 3rd instar larvae by the 17th generation of selection from a level of only 3.8-fold before selection (compared to susceptible strains). The selected population was named YPPF strain. Genetic analysis of pyriproxyfen resistance in YPPF houseflies revealed that resistance to pyriproxyfen in this strain was incompletely dominant and multifactorial. There were at least 4 dominant factors responsible for the resistance, with the most important factor being located on the 2ndchromosome and other factors on the 1st, 3rd and 5th chromosomes. Furthermore, bioassays of synergism showed that the resistance ratio in white pupae of M. domestica was depressed to 29-fold from 400-fold by a cytochrome P450 inhibitor, 2-propynyl 2,3,6-trichlorophenyl ether. These results indicate that P450 monooxygenase plays an important role in M. domestica resistance to pyriproxyfen.

The allergenic and antigenic cross-reactivities between a major recombinant Poa pratensis (Poa p) IX allergen, rKBG8.3, and its corresponding proteins of different grass pollens were examined. Immunoblotting of the proteins of thirteen different grass pollens using anti-rKBG8.3 antibodies indicated that Poa p IX-like proteins are present in ten other grass pollens, albeit in variable amounts and polymorphic forms. These proteins ranged in size from 20 to 88 kDa in different grass pollens. The percent relative binding determined for each grass pollen extract using allergic human sera showed a significant correlation (r = 0.891) with that of anti-rKBG8.3 antiserum. Moreover, there was a strong association (r = 0.901) between the Kentucky bluegrass extract and rKBG8.3 with respect to their inhibition of the binding of human IgE antibodies to allergens in grass pollen extracts. Taken together, these results suggest that the allergenic and antigenic epitopes of the Poa p IX-related proteins in some but not all grass pollens are similar in structure and specificities. It is concluded that the group IX allergens constitute a major family of homologous proteins in several grass pollens.

Purpose: This study compared the effect of magnesium-incorporated hydroxyapatite (MgHA) coating with that of HA coating on implant fixation in ovariectomized (OVX) rats. Materials and Methods: Coatings of HA and MgHA (10 mol% Ca²⁺ replaced by Mg²⁺) were prepared on the surface of titanium substrates using the sol-gel dip-coating method, and powders of HA and MgHA were produced by the same method. The two kinds of materials were then characterized by scanning electron microscopy and x-ray diffraction. Twelve weeks after bilateral ovariectomy, 18 OVX rats received implants in the distal femora; half of the implants were HA-coated and the other half were MgHA-coated. After 12 weeks of healing, rats were selected randomly for histomorphometry, microcomputed tomography evaluation, and biomechanical testing. Results: Surface characterization analysis demonstrated that the addition of Mg did not dramatically change the surface topography or apatite patterns of the coating. Histomorphometry revealed higher bone-to-implant contact and bone area ratio for MgHA-coated implants than for HA-coated implants. Microcomputed tomographic evaluation revealed improved trabecular parameters and increased osseointegration for MgHA-coated implants. Biomechanical testing revealed that the MgHA coating increased the maximum push-out force and interfacial shear strength compared to the HA coating. Conclusion: Mg incorporated into an HA coating on titanium implants could improve the biologic fixation of implants in osteoporotic bone.

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