(A) Note the heterochromatic chromocenter
formed by the sex chromosomes (arrow) and small heterochromatic blocks dispersed in T.
The liver examination after the injection of 1.7 mL/kg dose of iron oxide nanoparticles (Figure 5(c)) indicates hepatocytes with moderate anisokaryosis, formation of chromocenters and nucleoli, and moderate granular cytoplasmic degeneration.
The tubular cells with moderate anisokaryosis and anisochromia with formation of chromocenters and minimal granular cytoplasmic degeneration (HE, 600x) are also presented in Figure 6(b).
The specimen injected with a solution of 1.7 mL/kg iron oxide (Figure 6(c)) preserves the architecture, tubular cells with moderate anisokaryosis, and anisochromia with formation of chromocenters, moderate granulovacuolar cytoplasmic degeneration with focal clear cells, and moderate vascular congestion (HE, 400x).
In this case, sex chromosomes and autosomal polymorphisms should not be in genetic equilibrium and there should be differences in the extent of chromosome pairing and morphologies of chromocenters when putative parental and combinational types are compared.
We made more extensive collections at the Coeur d'Alene site in 2009 and 2010 to (1) verify the presence and frequencies of larvae identified in earlier collections, (2) test for genetic equilibrium among sex chromosomes and the most abundant autosomal polymorphism, IS-1, (3) determine the extent of chromosome pairing and morphology of chromocenters among parental and intermediate types and (4) determine the geographic extent of these types by analyzing larvae from three nearby sites to the west and four nearby sites to the east.
We averaged the two-dimensional areas (greatest length and width via an ocular micrometer) of the chromocenters (three amplified centric regions) from 10 Simulium saxosum/S.
The "count particles" function of the program was used to determine the following parameters: 1) chromocenter number per nucleus (N-CHR) and 2) relative area, as a percentage of the chromocenters per nucleus (R-CHR), representing a relative assessment of interphase heterochromatin.
Previous studies showing a latitudinal variation in chromocenter numbers in A.
Red arrows in (c) indicate the clusters of centromeric heterochromatin (chromocenters
) and white arrows show the selected CB.