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The fine structure of Johnston's organ in the pine sawfly, Neodiprion sertifer, was studied by electron microscopy to determine if there exists a dimorphism in this organ corresponding to the sexual dimorphism in antennal shape and surface area. The organ is made up of scolopidia that are ultrastructurally similar to those of other insects. The scolopidia, identical in both sexes, comprise three sensory cells bearing two types of sensory processes: Two are shorter and smaller in diameter than the third, which extends into the cuticle of the membrane connecting pedicel and flagellum and terminates at an epicuticular invagination. The dendrites and sensory processes are surrounded by two types of enveloping (glial) cells-a scolopale cell and an attachment cell. Other enveloping cells occur at different levels of the scolopidium. Sexual dimorphism is evident only in the numbers of scolopidial groups: Males have more groups with fewer scolopidia, but both sexes possess about the same total number of scolopidia., (Copyright © 1981 Wiley-Liss, Inc.)

The ultrastructure of the compound eyes of five species of mysids (Crustacea: Mysidacea), Praunus flexuosus, Siriella norvegica, Mysidopsis gibbosa, Neomysis integer and Erythrops serrata, is described. The ommatidia are constructed on a common plan, but there are considerable differences in detail. Common features include the arrangement of the cornea, crystalline cone and the basement membrane. The number of retinular cells differ: in Neomysis and Erythrops there are seven, whereas in the other species there are eight, the eighth cell forming a distal rhabdom, which consequently is lacking in the ommatidia of Neomysis and Erythrops. Another difference is the epirhabdom, which is lacking in Erythrops, but present in the other species. The epirhabdom is an extracellular structure, probably serving as a dioptric element. The pigment arrangement is similar in the first four species. The pigment shield consists of the distal pigment, distal reflecting pigment, proximal pigment (in the retinular cells) and the proximal reflecting pigment. The distal and proximal pigments are dark screening pigments. In addition to these, there are basal red pigment cells, which are mainly located below the basement membrane. In Erythrops there are three kinds of pigment cells: distal pigment cells, distal reflecting pigment cells and basal red pigment cells. Besides the basal red pigment cells, the distal pigment cells contain red pigment granules.

This study developed a situation-specific instrument that measures assertiveness of adolescents. The Assertiveness Scale for Adolescents (ASA), which contains 33 items, was constructed using a multiple-choice format with three response alternatives. Based on data from 682 elementary and secondary school students, adequate reliability and validity of the ASA were obtained when tested against several variables about which predictions could be made. Potential use of the instrument in clinical diagnosis and research was discussed.

Isolated rat adrenal cells in tissue culture, showing ACTH-induced corticosterone synthesis, were used as a model system for the study of adrenal metabolism and toxicity of 7,12-dimethylbenz[a]anthracene (DMBA). DMBA was metabolized at a rate of 10 pmol/min/10(6) cells and with a Km of 0.5 microM. Metabolite patterns and sensitivity to various AHH inhibitors suggest the involvement of an epoxide intermediate. In agreement with this proposal DMBA metabolite(s) were bound to cellular protein at a rate which was related to the AHH activity. Adrenal AHH was found to be insensitive to ACTH during a period of 24 h. Using ACTH-induced corticosterone synthesis as an indicator of cell damage the hepatic metabolite 7-hydroxymethyl-12-methyl-benz[a]anthracene was shown to be significantly more toxic than the parent compound DMBA. It is concluded that DMBA-dependent adrenal damage in vivo is due mainly to the liver metabolite 7-hydroxymethyl-12-methyl-benz[a]anthracene (7-OHM-12-MBA), possibly after secondary metabolic activation in the adrenal.

Administered to a total of 788 children from grade 5 (N = 133), 7 (N = 193), 9 (N = 151), 11 (N = 158), and 13 (N = 153) a modification of Ellis' 11 irrational beliefs questionnaire reformulated for use with younger children. Results showed a linear decrease of percent item endorsement from younger to older children on 8 of 11 irrational ideas. Analysis of variance on the mean number of irrational ideas endorsed showed significant differences between children. Results indicated that endorsing irrational beliefs is a function of age and provided construct validity for the instrument presented here. Research and counseling uses of the scale are discussed.

A nuclear encoded mitochondrial heat-shock protein hsp60 is required for the assembly into oligomeric complexes of proteins imported into the mitochondrial matrix. hsp60 is a member of the 'chaperonin' class of protein factors, which include the Escherichia coli groEL protein and the Rubisco subunit-binding protein of chloroplasts.

The turnip moth Agrotis segetum possesses seven different types of sensilla: four single-walled (SW), one double-walled (DW), one terminal-pore (TP), and one poreless sensilla (NP). The SW 1 and SW 2 sensilla have the same external appearance, being long and slender, but differ in the branching pattern of the sensory processes: unbranched and branched in SW 1 and SW 2, respectively. The SW 3 sensilla are shorter, sickle-shaped, and contain a large number of branches from the sensory processes. These three sensillar types are innervated by 2--3 sensory cells. The SW 4 sensilla are raisin-shaped and possess three profusely branched sensory processes. The DW sensilla are short and have apical slit-like pores. This sensillar type has 5--6 sensory processes. The TP sensilla possess five sensory processes, one of them terminates basally in a tubular body, the others in the apical part of the long cuticular bristle. The NP sensilla are stout and have apical conelike structures. Two of the sensory processes terminate in the apical part, the third proximally. The third sensory process has a lamellar pattern. The fine structure indicates the following functions: SW and DW sensilla: chemoreception; TP sensillum: chemoreception and mechanoreception; NP sensillum: thermoreception and hygroreception.

The adrenocorticolytic agent DMBA and its liver metabolite, 7-OHM-12-MBA, were investigated with respect to their mechanism of toxicity in cultured rat adrenal cells. Under proper growth conditions both hydrocarbons caused a reproducible and ACTH-dependent inhibition of steroidogenesis and cell death, similar to the effects of these agents on the rat adrenal in vivo. The toxicity of both DMBA and 7-OHM-12-MBA was partially prevented by antioxidants suggesting a common peroxidative mechanism of action. Studies with cytochrome P-450 inhibitors showed that toxicity of DMBA, but not 7-OHM-12-MBA, required a cytochrome P-450-dependent metabolic activation in order to be toxic. In addition, metyrapone, an efficient and specific inhibitor of the mitochondrial 11 beta-hydroxylase, provided protection against DMBA-induced toxicity, which is in agreement with previous observations that adrenal necrosis caused by DMBA apparently originates in mitochondria. It is proposed that both 7-OHM-12-MBA and DMBA, the latter after metabolism to mainly phenols, act as pseudosubstrates for steroid hydroxylases and initiate peroxidative damage through hydroxylase-generated superoxide anion, and/or hydrogen peroxide. These results indicate that both adrenal and hepatic metabolism of DMBA are potentially important in DMBA-induced adrenocorticolysis in vivo.

Primary cultures of rat adrenal cells, as well as rat adrenals in vivo, are sensitive to the potent carcinogen 7,12-dimethylbenz[a]anthracene and its liver metabolite 7-hydroxymethyl-12-methylbenz[a]anthracene, whereas unmethylated polycyclic aromatic hydrocarbons like benzo[a]pyrene or benzo[a]anthracene are ineffective. The adrenocorticolytic potencies of the hydrocarbons are affected by adrenocorticotrophic hormone and various steroids, cytochrome P450 inhibitors, and antioxidants. In the present investigation digitonin was used to fractionate cultured rat adrenal cells. It was found that the mitochondria and cytosol of the cells contained 3-5 nmol/10(6) cells (approximately 15%) and 20-30 nmol/10(6) cells (approximately 85%) of the total soluble cellular glutathione equivalents, respectively. After exposing the cells to 7-hydroxymethyl-12-methylbenz[a]anthracene in the culture medium, a time- and concentration-dependent selective oxidation of mitochondrial glutathione was observed, whereas the effect on the cytosolic glutathione was negligible. Under the same conditions, 7,12-dimethylbenz[a]anthracene and benzo[a]pyrene were unable to alter the redox levels of the subcellular pools of glutathione. Omission of adrenocorticotrophic hormone lowered the oxidation of mitochondrial glutathione induced by 7-hydroxymethyl-12-methylbenz[a]anthracene about twofold. The results suggest that rat adrenal cells contain two separate pools of glutathione, one cytosolic and one mitochondrial, of which the latter is selectively influenced by 7-hydroxymethyl-12-methylbenz[a]anthracene. Moreover, it is concluded that rat adrenal cells offer a unique model system for general studies of the effects of a selective oxidation of mitochondrial glutathione on various cell functions. These effects may constitute early changes in cytotoxicity, preceding, e.g., membrane damage and loss of cytosolic components.

We have investigated, comparatively, the ontogenetic development of the compound eye in larvae of a mysid (Neomysis) and a euphausiid (Thysanoessa) species and found it to be close to identical in the two species. The larval eye is of apposition type with special adaptations for planktonic life. The elongated dioptric apparatus is devoid of screening pigment and instead has a proximal lens optically isolating the ommatidium. The pigmented retina is extremely compressed making the eye largely transparent and presumably suitable for a planktonic life. The presence of this specialized type of eye in the planktonic larvae of euphausiids was known before but it is intriguing to find exactly the same type in mysids, spending their entire larval life as embryos in the female marsupium. A possible explanation is offered if mysids earlier in evolution had planktonic larvae. Upon reduction of free-living larvae, the transparent type of eye may have been preserved because there is no selection pressure on the larva to change it. In late larval life, both species transform their eyes to a refracting superposition type typical for adult mysids and euphausiids. The process of transformation and the functional connection between transparent apposition and superposition is described.