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Spermatogonial and primary spermatocyte chromosomes of Paragomphus lineatus (Selys) and Nepogomphus modestus (Selys) of family Gomphidae have been described on the basis of C-banding and NOR staining. Both the species possess 2n (♂) =23, n (♂) =12 without m chromosomes with XO(

Dihydronicotinamide riboside:quinone oxidoreductase (NQO2) is an enzyme that performs reduction reactions involved in antioxidant defense. We hypothesized that NQO2 hepatic drug clearance would develop in children over time, similar to NQO1. Using human liver cytosol (n = 117), the effects of age, sex, ethnicity, and weight on NQO2 expression and activity were probed. No significant correlations were observed. Biochemical activity of NQO2 was as high at birth as in adults (0.23 ± 0.04 nmol/min/mg protein, mean ± SEM, range 0-1.83). In contrast, modeled hepatic clearance through the NQO2 pathway was up to 10% of adult levels at birth, reaching predicted adult levels (0.3 ± 0.03 L/h) at 14 years of age. Comparisons between NQO1 and NQO2 in the same livers showed that neither protein (P = 0.32) nor activity (P = 0.23) correlated, confirming both orthologs are independently regulated. Because hepatic clearance through NQO2 does not mature until teenage years, compounds detoxified by this enzyme may be more deleterious in children.

Summary Male germ cell complement of Pantala flavescens belonging to the family Libellulidae has been investigated. Specimens were collected from the surrounding area of the Harike wetlands in the Punjab state of India. The species possesses 2n =23m as the diploid chromosome number, which is less than the type number, 2n =25m, of the family. In the chromosome complement, one autosomal bivalent is extraordinarily large due to the fusion of 2 autosomes and is responsible for the reduction in chromosome number. Precocious segregation of the m bivalent has also been noticed in some meiotic cells. This type of variations in the chromosome number and behaviour of m chromosomes indicate that the species is under the process of karyotypic evolution. Libellulidae is one of the largest families, with greatest number of species, in the suborder Anisoptera. From a cytological point of view, this family is well studied compared to other families; cytogenetical data pertains to 270 species, which is less than one third of the known libellulid species. In India, 470 species are taxonomically known, and out of these 85 species, belonging to 39 genera, are of the family Libellulidae. Karyological data is available on approximately 35 libellulid species Key words

Summary Neurobasis chinensis chinensis of the family Calopterygidae is the only species of this genus present in India. This species was collected from Andretta and Mcleodganj areas of Himachal Pradesh, India. The species possesses 2n=23 which is less than the type number (2n=25) of the family. The chromosome complement shows the presence of large pair of autosomes originated by the fusion of two autosome pairs and is responsible for the reduction in the chromosome number. This fusion has been confirmed by C-banding with the presence of two interstitial and terminal C-bands on the largest autosomal bivalent having two chiasmata while remaining autosomal bivalents possess terminal C-bands and single chiasma which is the characteristic feature of Odonata. Ag-NOR staining shows the presence of terminal NOR bands in seven autosomal bivalents and the X chromosome is rich in NORs. C-banding and Ag-NOR staining have been performed for the first time on this species.