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The possibility that symptoms of flooding damage in plants are primarily caused by an accumulation of ethylene was investigated using pot-grown sunflower (Helianthus annus) plants. When plants were flooded to the basal pairs of leaves, ethylene in roots and stems below the water line began to increase. This coincided with the start of hypocotyl hypertrophy and new root formation in hypocotyls, which continued for 14-16 days. There were highly significant correlations between ethylene concentration and number of roots and hypocotyl diameter. After approximately 4 days of flooding, ethylene concentrations in stems between nodes for the 1st and 3rd basal pairs of leaves started to increase, coinciding with initiation of chlorophyll breakdown and epinasty of the 2nd basal pairs of leaves. Thus, there were correlations between ethylene concentration and chlorophyll breakdown and epinasty, The lower the leaves, the more chlorophyll breakdown among 1st, 2nd, 3rd, and 4th basal pairs of leaves. The longer the flooding, the more severe the flooding damage; and even when returned to normal condition, plants flooded longer than 3 days were not able to recover front flooding damage. A gas chromatographic study revealed that Ethephon was absorbed by roots and decomposed to ethylene in the plant. Damage symptoms caused by soil application of Ethephon, such as reduced stem height, chlorophyll breakdown, epinasty of the 2nd basal pairs of leaves, and hypocotyl hypertrophy, were almost identical with those caused by soil flooding treatment, Microscopic studies revealed that radially enlarged cells and increased intercellular spaces in the cortex were the major contribution to the increased hypocotyl diameter in both flooded and Ethephon-treated plants. It is concluded that the increase in ethylene concentration in flooded plants is largely, although not exclusively, responsible for flooding damage symptoms. [ABSTRACT FROM AUTHOR]

Hypertrophic scars, mature scars from hypertrophic and non-hypertrophic healing, and normal skin have been examined by biopsy and studied for histological patterns consistent with each case. Normal skin presents collagen appearing randomly of oriented and with a marked waviness. Under stress the collagen reflect, a previously masked orthogonal ply pattern. The hypertrophic scar may be characterized by a consistent pattern of collagen, which is never found in normal skin of a mature scar. This pattern, consistent with the most active stage of hypertrophy, contain nodules of collagen. They are highly compact, often with a capsule-like band about their periphery. Blood vessels are frequently observed about the periphery. The early stage ot hypertrophic scarring displays bundles ox tracts in curvilinear form, several of which together demonstrate a whorl-like arrangement. Whether or not the whorl arrangements proceed to form a nodule or bypass this stage to begin maturation is dependent on unknown factors. By electron microscopy, the nodule is seen to contain highly stellate fibroblasts with dilated rough endoplasmic reticulum and few other organelles. The diameter of the collagen filaments is about half that observed in normal skin. We conclude that hypertrophic scarring involves the formation of collagenous nodules composed of tightly packed collagen. Nodular formation appears to reflect the most active and the worst phase of hypertrophic scarring. [ABSTRACT FROM AUTHOR]

A majority of the males of the brackish water shrimp, Macrobrachium idae, show a hypertrophy in the length of the second cheliped, the length and spinuosity of the appendix masculina and the width of the vas deferens, during the breeding season. Statistical analyses of the measurements of these characters show that this hypertrophy has only very little correlation to the size of the individual, and that the above sex characters have marked variation in a population having the same body length. The hypertrophy of these structures is more linked with the extent of development of the androgenic gland. Also, in such individuals, the androgenic gland shows signs of increased secretory activity as evidenced by increase in size of the cells, vacuolisation of cytoplasm and presence of degenerative areas. It is suggested that there is a direct relation between the secretory activity of the androgenic gland and the hypertrophy of these structures i.e. there is a "cause and effect" relation between the androgenic gland and the primary and secondary sex characters. [ABSTRACT FROM AUTHOR]

The effects of gonadectomy on the cytological structure of the hypophysis and interrenal tissue of Clarias batrachus have been investigated. Forty days after gonadectomy remarkable hypertrophy of certain cyanophils, identified later as gonadotrops, has been observed followed by hyperplasia. The somatotrops also seem to undergo similar changes, and as a result the proximal pars distalis (PPD) increases enormously and encroaches upon the pars intermedia (PT). The gonadotrops undergo a gradual degranulation and become devoid of stainable cytoplasm by 90 days. No signet ring cells have been noticed at any stage. The cyanophils in the ventral region of the PPD, identified as thyrotrops, also show degranulation, but to a comparatively limited degree. The ACTH cells undergo gradual hypertrophy and degranulation. A progressive increase is noticed in the nuclear diameter. The interrenal cells are activated as indicated by the enhanced nuclear indices. It is suggested that a I all in gonadal steroids may result in ACTH release which in turn activates the interrenal cells. [ABSTRACT FROM AUTHOR]

Explores the relationship between Wilms' tumor and congenital hemihypertrophy in children. Chromosome analysis of peripheral-blood leukocyte cultures; Levels of urinary gonadotropin excretion; Congenital defects following exposure to chloroquine phosphate during pregnancy.

Areas occupied by Hassall's corpuscles were measured by planimetry of histological sections of guinea-pigs' thymus glands that had been involuted by one of three methods: (1) local X-irradiation of the thymus, or (2) restriction of food intake, or (3) systemic injections of cortisone. The corpuscular area increased two- to three-fold compared with control glands and this increase occurred before lobules began to shrink. Hassall's corpuscles hypertrophy simultaneously with diminution in width of the cortex, i.e. with lysis of thymocytes. Hence, it is argued that the area taken up by the corpuscles provides a measure of thymocyte destruction during involution. Moreover, since the corpuscles are markedly diminished during reconstitution, 3–4 weeks after X-irradiation, their size is a further reflection of cellular turnover in the thymus. [ABSTRACT FROM AUTHOR]