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Abstract:We quantified the repeatability of >900 individual measures of hind foot length from 2 French populations of roe deer (Capreolus capreolus) monitored by capture-recapture. We found a high repeatability (i.e., high intra-class correlation, 0.76, 95% CI = 0.72–0.83 and 0.92, 95% CI = 0.91–0.95) in both populations. We also found that inexperienced observers reached a high level of intra- (1.00, 95% CI = 0.96–1.00) and inter-observer repeatability (0.99, 95% CI = 0.98–1.00) when measuring hind foot length of harvested animals with a tool specifically designed for this task. Managers should pay particular attention to limit measurement errors because unreliable measurements require an increased sample size to assess individual variation and can mask biological patterns.

There is a currently growing interest in the development of histone deacetylase inhibitors (HDACs) as anticancer agents. Histone deacetylases are critically important in the functional regulation of gene transcription as well as in chromatin structure remodeling. A number of small molecule inhibitors of HDAC, such as the naturally occurring trichostatin A (TSA), as well as synthetic compounds, such as suberoylanilide hydroxamic acid (SAHA), scriptaid, oxamflatin or MS-275, have been reported to induce differentiation of several cancer cell lines and suppress cell proliferation. This article will review the recent progress being made in our laboratories in the development of two new families of potent HDAC inhibitors: sulfonamide hydroxamic acids and anilides, as well as TSA-like straight chain derivatives. Some of these compounds inhibit partially purified recombinant human HDAC enzymes with IC50s in the micromolar to low nanomolar range and can induce hyperacetylation of histones in human cancer cells. These compounds significantly inhibit proliferation, induce expression of p21WAF1 / Cip1, and cause cell cycle arrest in various human cancer cells. The lead candidates were screened in a panel of human tumor and normal cell lines. The inhibition of HDAC activity represents a novel approach for intervening in cell cycle regulation and may be used in future cancer therapies. The structure-activity relationships, the antiproliferative activity and the in vivo efficacy are discussed.

AbstractAmong-individual variation of life history traits in a given population of deer has most often been accounted for by differences among sex and age classes and by current environmental variation (mostly changes in density and climatic conditions). However, among-individual differences in fitness can also be generated by differences in environmental conditions during the year of birth. Such cohort effects can be divided into two different components. First, among-year differences in environmental conditions at birth may produce large yearly variation in recruitment that generates a direct numerical effect (i.e., a high proportion of newborns are recruited in good years, whereas very low proportions are recruited when environmental conditions encountered by newborns during their first weeks of life are poor). Second, when recruited into the population, individuals born in a good year may reproduce earlier, reach a larger body mass, and have a higher reproductive success than individuals born in a poor year. We call the long-lasting influence on individual fitness of environmental conditions during the year of birth a delayed quality effect. Here, we first review briefly evidence of numerical and quality effects recently accumulated in deer populations. Then, by using long-term monitoring (> 20 y) of two contrasted roe deer (Capreolus capreolus) populations, we assess the influence of the among-cohort differences in reproductive traits, age- and sex-specific survival rates, and population growth rate. Results show that cohort effects (1) are widespread in deer populations and (2) may have a major influence on population dynamics, especially in low-performance populations. Cohort effects should therefore be accounted for in management plans of deer populations.

Body mass is a key determinant of fitness components in many organisms, and adult mass varies considerably among individuals within populations. These variations have several causes, involve temporal and spatial factors, and are not yet well understood. We use longterm data from 20 roe deer cohorts (197796) in a 2600 ha study area (Chizé, western France) with two habitats contrasting in quality (rich oak forest in the North versus poor beech forest in the South) to analyse the effects of both cohort and habitat quality on adult mass (i.e. median body mass between 4 and 10 years of age) of roe deer (Capreolus capreolus). Cohort strongly influenced the adult body mass of roe deer in both sexes: males born in 1994 were 5.2 kg heavier when aged between 4 and 10 years old than males born in 1986, while females born in 1995 were 4.7 kg heavier between 4 and 10 years old than females born in 1982. For a given cohort, adult males were, on average, 0.9 kg heavier in the rich oak forest than in the poor beech forest. A similar trend occurred for adult females (0.5 kg heavier in the oak forest). The effects of cohort and habitat were additive and accounted for ca. 40 of the variation observed in the adult mass of roe deer at Chizé (males: 41.2; females: 40.2). Population density during the spring of the birth accounted for about 35 of cohort variation, whereas rainfall in MayJune had no effect. Such delayed effects of density at birth on adult body mass probably affect population dynamics, and might constitute a mechanism by which delayed densitydependence occurs in ungulate populations.

In female vertebrates, differences in fitness often correspond to differences in phenotypic quality, suggesting that larger females have greater fitness. Variation in individual fitness can result from variation in life span andor variation in yearly reproductive success, but no study has yet assessed the relationships between the components of fitness and phenotypic quality while controlling for life span. We tried to fill this gap using data from long–term monitoring (23 years) of marked roe deer and bighorn sheep, two ungulates with very different life histories. In both species, we found a strong positive relationship between an adult female's mass and her probability of reaching old age: over the long term, bigger is indeed better for ungulate females. On the other hand, we found no evidence in either species that heavier females had higher fitness when differences in life span were accounted for: over the short term, bigger is not necessarily better. Our results indicate that, while broad differences in phenotypic quality affect individual fitness, when differences in life span are accounted for phenotypic quality has no residual effect on fitness. Therefore, within a given range of phenotypic quality, bigger is not always better, for reasons which may differ between species.

The C-3 – C-17 segment of boromycin having five asymmetric centers was synthesized from D-arabinose and D-glucose as chiral precursors. Constitutional and stereochemical identity was established by comparison of the synthetic product with a sample obtained from the degradation of the antibiotic.

Abstract: Time- and sex-specific summer survival of roe deer fawns was estimated using capture-mark-recapture methods in two enclosed populations living in contrasting conditions. The population of Trois Fontaines (eastern France) was roughly constant in size throughout the study period, while in Chizé (western France), the population experienced frequent summer droughts and numbers decreased continuously during the study. Early survival of fawns was low and highly variable over the years at both Chizé and Trois Fontaines, and demonstrated marked variations between cohorts that need to be taken into account when modelling roe deer population dynamics. In Trois Fontaines, fawn survival was positively correlated with early body growth and total rainfall in May and June. In Chizé, fawn survival decreased with increasing density and tended to increase with increasing rainfall in May and June and adult female body mass. These factors explained more than 75% of the variability in early survival observed in both populations. Variation between cohorts had different consequences for the two populations. At Trois Fontaines, cohort variation was limited to a numerical effect on early survival. However at Chizé, cohort variation was long-lasting and affected the phenotypic quality of survivors at later ages, and thereby future survival and breeding abilities (both numerical and quality effects). Male and female fawns had similar survival over their first summer in both populations. This result contrasts with the lower survival of young males often observed in ungulates. Two ultimate causes can be proposed to account for the low and variable survival of roe deer fawns over the first summer: the high energy expenditures incurred by does during each breeding attempt and/or the low absolute body size of newborn roe deer fawns.

The role of tooth wear as a proximate cause of senescence in ruminants has recently been highlighted. There are two competing hypotheses to explain variation in tooth height and wear; the diet-quality hypothesis predicting increased wear in low-quality habitats, and the life-history hypothesis predicting molar height to be related to expected longevity. We compared tooth height and wear from roe deer of known age from two contrasting populations of roe deer (Capreolus capreolus) in France: Trois Fontaines (TF) with good habitat and shorter animal life expectancy and Chizé (CH) with poor habitat and longer animal life expectancy. There was no population difference in tooth wear, leading to rejection of the diet-quality hypothesis. However, despite their smaller body size, initial molar height for animals from CH was larger than for animals from TF. This provides the first evidence that variation in longevity between populations can lead to differences in molar height within a species.

Using C-furanosides as chiral precursors of (Z,E) 1,3-dienes has permitted the synthesis of two leukotriene B4analogues: 3-thia-LTB4and 3-thia-20,20,20-trifluoro-LTB4.

Births are highly synchronized among females in many mammal populations in temperate areas. Although laying date for a given female is also repeatable within populations of birds, limited evidence suggests low repeatability of parturition date for individual females in mammals, and between-population variability in repeatability has never, to our knowledge, been assessed. We quantified the repeatability of parturition date for individual females in five populations of roe deer, which we found to vary between 0.54 and 0.93. Each year, some females gave birth consistently earlier in the year, whereas others gave birth consistently later. In addition, all females followed the same lifetime trajectory for parturition date, giving birth progressively earlier as they aged. Giving birth early should allow mothers to increase offspring survival, although few females managed to do so. The marked repeatability of parturition date in roe deer females is the highest ever reported for a mammal, suggesting low phenotypic plasticity in this trait.

We investigated age-specific variation in male yearly breeding success (YBS) using genetic estimates obtained from 2 populations of a territorial ungulate, the European roe deer (Capreolus capreolus). YBS in both populations was markedly age-structured, with 3 distinct stages, supporting the dome-shaped pattern of variation commonly reported for age-dependent variation in life-history traits of ungulates. YBS was low at 2 years of age, peaked at 3–8 years of age, and tended to decline afterwards (senescence). Most males successfully reproduced for the 1st time at 3 years of age, which is well after their physiological maturity. The few successful young males (i.e., 2 year olds) were likely fast-growing individuals that could successfully hold a territory. The high variance in YBS and antler size for old males at Bogesund, Sweden, suggests that only some males of this age Class are able to maintain large antlers and, hence, retain their territories.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.