Inhibition of phenotype modulation, growth, and migration of vascular smooth muscle cells by a guanosine-rich 30-mer phosphorothioate oligodeoxynucleotide

The testing of a 30-mer dG-rich phosphorothioate oligodeoxynucleotide (LG4PS) for effects on the behaviour of vascular smooth muscle cells (VSMC) in vitro and in vivo is described. LG4PS at 0.3 mu M inhibited significantly the phenotype modulation of freshly isolated rabbit VSMC, and cell outgrowth from pig aortic explants was inhibited similar to 80% by 5 mu M LG4PS. The growth of proliferating rabbit and pig VSMC was inhibited similar to 70% by 0.3 mu M and 5 mu M LG4PS, respectively. Though less marked, the antiproliferative effects of LG4PS on human VSMC were comparable to those obtained with heparin. The cytotoxic effects of LG4PS on VSMC in vitro were low. Despite these promising results, adventitial application of 2-200 nmol LG4PS in pluronic gel failed to reduce vascular hyperplasia in balloon-injured rabbit carotid arteries, and the highest dose caused extensive mortality. (C) 1997 Academic Press Limited.

Insulin-like growth factor-I and transferrin mediate growth and survival of Chinese hamster ovary cells

The aim of this investigation was to elucidate the roles of insulin-like growth factor-I (IGF-I) and transferrin in the survival and proliferation of Chinese hamster ovary (CHO) cells upon withdrawal of serum. For this purpose, we employed DNA analysis and now cytometry to compare CHO cell lines expressing either IGF-I alone or IGF-I and transferrin. The ability of cells to cycle and the occurrence of apoptosis were monitored in these cells in serum-free medium. These results indicate that IGF-I alone is able to maintain the viability of CHO cells for an extended length of time in the absence of serum. Transferrin alone does not promote survival or proliferation. Only in the presence of both IGF-I and transferrin do cells survive and proliferate. Therefore, in attached CHO cultures, IGF-I alone does not stimulate cell proliferation but is a requirement for growth in serum-free medium in cooperation with transferrin. We report on the dual role of IGF-I as a survival factor in CHO cells and its interlocking role with transferrin to stimulate cell growth.

The effects of density on the growth and survival of different families of juvenile Penaeus japonicus Bate

Variations in the growth and survival of six families of juvenile (initial mean weight = 4.16 g) Penaeus japonicus were examined at two densities (48 and 144 individuals m(-2)) in a controlled laboratory experiment. Survival was very high throughout the experiment (95.4%), but differed significantly between densities and rearing tanks. Family, sex and family x density interaction did not significantly affect survival. Mean specific growth rate (SGR) of the shrimp was 18% faster at the low density (1.93 +/- 0.05% day(-1)) than at high density (1.64 +/- 0.03% day(-1)). However, there was a small but significant interaction between family and density indicating that growth of the families was not consistent at both densities. The inconsistent growth of the families across the two densities resulted in a change in the relative performance (ranking) of families at each density. Sex, rearing tank and rearing cage also affected growth of the shrimp. Mean SGR of the females (1.79 +/- 0.03% day(-1)) was 5% faster than males (1.70 +/- 0.03% day(-1)) when averaged across both densities. Shrimp grew significantly faster in rearing tank 3 than rearing tank 1 or 2 at both densities. Results of the present study suggest that family x density interaction could affect the efficiency of selection for growth if shrimp stocks produced from shrimp breeding programs are to be grown across a wide range of densities. Crown Copyright (C) 2004 Published by Elsevier B.V. All rights reserved.

The Runx1 transcription factor controls CSF-1-dependent and -independent growth and survival of macrophages

Gene translocations that repress the function of the Runx1 transcription factor play a critical role in the development of myeloid leukemia. In this report, we demonstrate that Runx1 precisely regulates c-fms (CSF-1 receptor) gene expression. Runx1 controlled expression by binding to multiple sites within the mouse c-fms gene, allowing interaction between promoter and downstream enhancer elements. The runx1 and c-fms genes showed an identical pattern of expression in mature macrophages. Runx1 expression was repressed in CSF-1 stimulated, proliferating bone marrow-derived macrophages (BMM) and significantly increased in quiescent, CSF-1 starved cells. The RAW264.7 and Mono-Mac-6, macrophage-like cell lines expressed low levels of Runx1 and both showed growth arrest and cell death with ectopic expression of Runx1. The EM-3 cell line, which represents an early myeloid progenitor cell line, showed growth arrest with Runx1 expression in the absence of any detectable changes in cell differentiation. These findings suggest that Runx1 regulates growth and survival of myeloid cells and provide a novel insight into the role of Runx family gene translocations in leukemogenesis.

Post-hatching growth and development of the pectoral and pelvic limbs in the black noddy, Anous minutus

The black tern (Anous minutus) uses a semi-precocial growth strategy. Terrestrial locomotor capacity occurs soon after hatching, but pectoral limb development is delayed and flight is not possible until about post-hatching day 50. A growth series (hatchlings to fledglings) was used to explore how limb musculoskeletal development varied with body mass. In the pelvic limb, bone lengths scaled isometrically or with negative allometry. Gastrocnemius muscle mass and the failure load and stiffness of the tibiotarsus scaled isometrically. In the pectoral limb, pectoralis and supracoracoideus muscle masses increased with strong positive allometry that was mirrored by increases in wing bone strength and stiffness. Bending strength (σult) and modulus (E) remained fairly constant throughout development to fledging for all limb bones. The moment of inertia (I) scaled with negative allometry for the tibiotarsus and with strong positive allometry in the wing bones. Differences in σult and E of the tibiotarsus between pre-fledged chicks and adults was due, primarily, to increases in bone density rather than increases in the moment of inertia of the skeletal elements, whereas σult of wing bones was a function of increases in both bone density and I. Early development of functional pelvic limbs in tree-nesting birds is relatively unusual, and presumably reflects a familial trait that does not appear to compromise breeding success in this species.

Effects of high temperature on the growth and composition of sugarcane internodes

Sugarcane grown in the Ord River district of Western Australia has lower sucrose content than expected from earlier trials and experience in other irrigated districts. High temperatures have been hypothesised as a possible cause. The effects of high temperature (above 32 degrees C) on growth and carbon partitioning were investigated. A temperature regime of (25-38 degrees C) was compared with (23-33 degrees C). In one experiment, 7-month-old plants of cvv. Q117 and Q158 were subjected to the treatments for 2 months. In another experiment, the plants were allowed to regrow (ratoon) for 6 months. In both experiments, the higher temperature resulted in more, shorter internodes and higher moisture content. Most internodes from plants in the higher temperature treatment had lower sucrose content than internodes from the lower temperature. On a dry mass basis the internodes from the plants in the higher temperature had proportionately more fibre and hexoses but lower sucrose. Combined with an increased number of nodes in a stem of similar or shorter length this would result in higher stalk fibre and lower sucrose content. The data provided evidence that sugarcane partitions less carbon to stored sucrose when grown under high compared with low temperatures. The two cultivars partitioned carbon between soluble (sugars) and insoluble (fibre) fractions to different degrees. These experiments also indicate that the current models describing leaf appearance and perhaps sugarcane growth at temperatures above 32 degrees C, in general, need revision.

Comparison of growth and development of the red-tailed phascogale (Phascogale calura) in three captive colonies

The red-tailed phascogale ( Phascogale calura) is an endangered dasyurid species that has recently been brought into captivity in an effort to increase numbers before release back into the wild. As part of investigations into the reproductive biology of the species, information on the growth and development of young was collected throughout lactation from litters raised in three separate colonies. Growth curves for aging young throughout lactation and a timetable of developmental changes were constructed. While two colonies, with fourth- and fifth-generation captive animals, showed no significant difference in growth, animals from a third colony that had been wild caught before breeding displayed a slower rate of growth from 34 days of age. The pattern of development resembled that of other dasyurids, with young left in the nest from 44 days of age, fully furred by 78 days and weaned between 90 and 110 days. Captive phascogales invest heavily in their young, with litters weighing 380 +/- 67% of maternal bodyweight at weaning.