Correlations between baltic amber and Pinus resins

The composition of the acid fractions of four pine resins has been studied before and after an ‘ageing’ process. Correlations are established between Baltic amber and ‘aged’ Pinus halepensis resin.     

Physiological ageing of potato tubers: A Review

Numerous theories have been proposed to describe the complex process of ageing in biological systems. Two general groups of ageing theories currently exist: 1) stochastic where the accumulation of random molecular damage leads to loss of information vital to the cell; and, 2) systemic where an organised, genetically based sequence of metabolic activities leads to programmed ageing. Whether these are acceptable models of ageing in potato tubers is unknown although the tuber could provide a useful experimental system for studying ageing. An initial requirement for advancing the concept of ageing in potato tubers must centre on the development of a suitable ageing index. A review of the literature suggests that a modified approach to ‘sprouting capacity’ and ‘incubation period’ may allow tuber ageing to be described in mathematical terms that would, in turn, facilitate the development of a physiological ageing index as well as temperature sensitive predictive models. Although a number of biochemical studies of ageing have been pursued, the development of adequate biomarkers has yet to achieve a coordinated level of development as found in a range of organisms. For example, ageing in other biological systems may be viewed as an outcome of an accumulation of random molecular damage and may be primarily caused by a changing balance between reactive oxygen species and diminishing levels of protective agents such as superoxide dismutase, alpha‐tocopherol or vitamin C. The exploration of these and similar problems in the context of appropriate modelling approaches should allow a better understanding of physiological ageing in potato tubers.     

EQUALITY AND THE DUTY TO RETARD HUMAN AGEING

Where does the aspiration to retard human ageing fit in the ‘big picture’ of medical necessities and the requirements of just healthcare? Is there a duty to retard human ageing? And if so, how much should we invest in the basic science that studies the biology of ageing and could lead to interventions that modify the biological processes of human ageing? I consider two prominent accounts of equality and just healthcare – Norman Daniels's application of the principle of fair equality of opportunity and Ronald Dworkin's account of equality of resources – and conclude that, once suitably amended and revised, both actually support the conclusion that anti‐ageing research is important and could lead to interventions that ought to be considered ‘medical necessities’.     

Invertebrate gerontology: The age mutations of Caenorhabditis elegans

Ageing is a complex phenomenon which remains a major challenge to modern biology. Although the evolutionary biology of ageing is well understood, the mechanisms that limit lifespan are unknown. The isolation and analysis of single-gene mutations which extend lifespan (Age mutations) is likely to reveal processes which influence ageing. Caenorhabditis elegans is the only metazoan in which Age mutations have been identified. The Age mutations not only prolong life, but also confer a complex array of other phenotypes. Some of these phenotypes provide clues to the evolutionary origins of these genes while others allude to mechanisms of lifespan-extension. Many of the Age genes interact and share a second common phenotype, that of stress resistance. Rather than invertebrate ageing being determined by a ‘clock mechanism’, a picture is emerging of ageing as a non-adaptive process determined, in part, by resistance to intrinsic stress mediated by stress-response genes.     

Cellular ageing mechanisms in osteoarthritis

Age is the strongest independent risk factor for the development of osteoarthritis (OA) and for many years this was assumed to be due to repetitive microtrauma of the joint surface over time, the so-called ‘wear and tear’ arthritis. As our understanding of OA pathogenesis has become more refined, it has changed our appreciation of the role of ageing on disease. Cartilage breakdown in disease is not a passive process but one involving induction and activation of specific matrix-degrading enzymes; chondrocytes are exquisitely sensitive to changes in the mechanical, inflammatory and metabolic environment of the joint; cartilage is continuously adapting to these changes by altering its matrix. Ageing influences all of these processes. In this review, we will discuss how ageing affects tissue structure, joint use and the cellular metabolism. We describe what is known about pathways implicated in ageing in other model systems and discuss the potential value of targeting these pathways in OA.     

The Age of Decline? Anxieties about Ageing in Japan

In the context of unprecedented life expectancy, the social position of the Japanese elderly is changing. Anxieties related to ageing are widely experienced by people of all ages and on a number of levels, including nationwide concerns over the ‘ageing population’ and its economic consequences; the ageing of local communities; on an interpersonal level, as older relatives may require care and support; and, finally, in relation to one's own ageing. These anxieties are examined based on ethnographic research in the city of Osaka. The concept of ikigai, often equated with purpose in life but closely associated with the elderly in public discourse, is used to illustrate how ageing implicates a number of apparently unconnected issues. It is argued that anxieties about ageing may ultimately achieve such prominence because they give focus to a range of fundamental human concerns with meaning, death, freedom, and isolation.     

‘Beach-Boy Elders’ and ‘Young Big-Men’: Subverting the Temporalities of Ageing in Kenya's Ethno-Erotic Economies

ABSTRACT

In the 1980s, Samburu men from northern Kenya began migrating to coastal tourist resorts to sell souvenirs and perform traditional dances for European tourists. Many of them engaged in transactional sex or marriages with European women attracted to the image of the exotic African young male warrior. Through relationships with European women, some Samburu men managed to rapidly accumulate wealth, becoming so-called ‘young big-men’. As a way to transform their wealth into more durable forms of respectability, these men used their money to marry local women and speed up their ritual initiation into elderhood. Meanwhile, there also emerged the figure of ‘beach-boy elders’, men who aged before accumulating sufficient wealth. They returned to coastal tourist resorts, dressed as young warriors, and waited to find European partners. In the article, I argue that beach-boy elders and young big-men produce queer moments in the temporalities of ageing, in that they subvert normative expectations of ageing at the very same time that they seek to produce them.     

II. Phospholipid exchange and size enlargement in sonicated vesicles induced by a ‘critical’ fatty acid concentration

Size enlargement of dipalmitoyl phosphatidylcholine vesicles was greatly accelerated in the range of the phase-transition temperatures, when fatty acid concentration was above a threshold level (‘critical’ concentration). This ‘critical’ concentration varied with the length of the fatty acid chain. The size enlargement process had second-order kinetics dependent on the vesicle concentration. Alkaline pH and low ionic strength inhibited the rate of size enlargement.Phospholipid exchange between dimyristoyl and dipalmitoyl phosphatidylcholine vesicles increased abruptly above a ‘critical’ fatty acid concentration. The donor vesicles were those vesicles in which fatty acids reached the ‘critical’ concentration. The phospholipid exchange occurred both in fluid- and in solid-state vesicles. The ‘critical’ fatty acid concentration accelerating the phospholipid exchange process was lower than that accelerating the size enlargement process.The phospholipid exchange process explained in terms of a diminished hydrophobic attraction among the phospholipid molecules of the bilayer occurs via a free phospholipid molecule transfer through the aqueous phase. The size enlargement process is interpreted in terms of high fatty acid concentration in the membrane fluid domains. The membrane structure is locally perturbed inducing vesicle sticking after collision.     

丹桂和籽银桂花芽分化的研究

采用石蜡切片技术, 对不育的丹桂(Osmanthus fragrans ‘Dangui’ )和可育的籽银桂(Osmanthus fragrans ‘Ziyingui’)花芽分化的过程进行了研究。结果表明, 桂花(Osmanthus fragrans Lour.)花芽形态分化可分为花芽分化初始期、总苞分化期、花原基分化期、顶花花被分化期、雄蕊分化期和雌蕊分化期6个阶段。雄蕊的发育在丹桂和籽银桂之间基本没有区别, 都能形成完整的花粉囊和成熟的花粉粒。但是, 雌蕊的发育在可育的籽银桂与不育的丹桂之间存在明显差异。根据花芽分化的过程证明, 丹桂的不育是由于雌蕊发育不正常导致的。     

Intrauterine programming of ageing

Ageing is an unavoidable corollary to being alive; the most intuitive interpretation of ageing being that it is the consequence of progressive body degeneration. In agreement with this, current models propose that ageing occurs through a stepwise accumulation of DNA damage, which ultimately limits the regenerative capacity of tissues. On the other hand, there is increasing evidence that fetal distress can influence the development of disease in adult life, a phenomenon known as ‘intrauterine programming’. The extent to which an intrauterine exposure to DNA damage can compromise lifespan remains unclear. My group has recently generated a murine model of a human syndrome linked to defective DNA repair and observed that these animals age prematurely, but the accumulation of DNA damage is restricted mostly to the embryonic period. Here, I discuss the implications of this finding and propose that ageing can be influenced by fetal distress.     

Role of age and tumour stage in the temporal pattern of 'cure' from stomach cancer: a population-based study in Osaka, Japan

Objectives: To evaluate progress in stomach cancer care in Japan since 1975. Design: Population-based study of data extracted from the Osaka Cancer Registry. Setting: Population-based cancer registry in the area of Osaka Prefecture. Participants: All 66,032 cases diagnosed with a stomach cancer in Osaka Prefecture, Japan between 1975 and 2000 and registered in the Osaka Cancer Registry. Main outcome measures: ‘Cure’ fraction and median survival time for ‘uncured’ patients were estimated with multivariable mixture ‘cure’ model. The role played by age and stage at diagnosis on the changes in ‘cure’ parameters between 1975 and 2000 was evaluated. Missing stage was handled by multiple imputation approach. Results: More than 50% of the patients diagnosed with a stomach cancer in 1996–2000 were estimated ‘cured’ from their cancer, corresponding to a 20% increase since 1975–1980. Median survival time for ‘uncured’ patients however remained unchanged at about 8 months. ‘Cure’ fraction was over 85% for localised tumours and 30% for regional tumours, but stayed as low as 2.5% for distant metastatic cancers. Improvement was underestimated by about 10% because of ageing of cancer patients. Changes in stage distribution explained up to 40% of the increase in ‘cure’ fraction among men and up to 13% in women. Overdiagnosis was unlikely to play any role in these patterns. Conclusions: ‘Cure’ fraction from stomach cancer dramatically increased in Osaka, Japan since 1975, partly because of earlier stage at diagnosis, but mostly due to improvement in treatment of stomach cancer patients. This study, based on a leading country in term of stomach cancer management, provides insightful results for other countries in which ‘cure’ fraction is usually much lower.     

A senescence up-regulated protein: the rat thyroxine-binding globulin (TBG)

Thyroxine-binding globulin (TBG), the major carrier of thyroid hormones in human serum, was thought to be absent in most species, including rodents. We demonstrated recently that in fact the rat possesses a TBG gene, virtually non-expressed in young adults, bu actively transcribed during post-natal development. We now find that the TBG gene is als increasingly re-expressed during senescence. Evidence is presented suggesting that physiologically decreased thyroid hormone levels, characteristic of neonates and of ageing rats, might consitute a common factor inducing up-regulation of TBG in both developmental and ageing processes. Rat TBG is to our knowledge the first biochemical ‘positive’ (i.e increasing) marker of non-pathological senescence, expressed at both biosynthetic and bloodstream levels.     

Oral health care in long‐term care facilities for elderly people in southern Brazil: a conceptual framework

doi:10.1111/j.1741‐2358.2009.00280.x
Oral health care in long‐term care facilities for elderly people in southern Brazil: a conceptual framework Objective: To present a theoretical model for understanding oral health care for the elderly in the context of long‐term care institutions (LTCI). Methods: Open‐ended individual interviews were conducted with the elderly residing in LTCI, their carers, nursing technicians and nurses, directors of care, dental surgeons and managers of public health services. A grounded theory methodological approach was adopted for data collection and analysis. Results: The emerging core category revealed a basic social process: ‘Promoting oral health care for the elderly based on the context of LTCI’. This process was composed of two contradicting yet correlated aspects: the oral health care does not minimise the poor oral epidemiological condition, and at the same time, there was a continued improvement in the oral care expressed by better care practices. These aspects were related to the: attribution of meaning to oral health, social determination of oral health, the ageing process, interactions established in the oral health care practices, oral health care management in LTCI, inclusion of oral health care into the political–organisational dimension and possibility of conjecturing better oral health care practices. Conclusion: The core concept of ‘Promotion of oral health care for elderly people based on the context of LTCI’ is capable of explaining the variations in the structure and process of LTCI, as well as in helping to understand the meaning of the oral health care practices for the institutionalised elderly.     

Management of multicellular senescence and oxidative stress

Progressively sophisticated understanding of cellular and molecular processes that contribute to age‐related physical deterioration is being gained from ongoing research into cancer, chronic inflammatory syndromes and other serious disorders that increase with age. Particularly valuable insight has resulted from characterization of how senescent cells affect the tissues in which they form in ways that decrease an organism's overall viability. Increasingly, the underlying pathophysiology of ageing is recognized as a consequence of oxidative damage. This leads to hyperactivity of cell growth pathways, prominently including mTOR (mammalian target of rapamycin), that contribute to a build‐up in cells of toxic aggregates such as progerin (a mutant nuclear cytoskeletal protein), lipofuscin and other cellular debris, triggering formation of senescent cellular phenotypes, which interact destructively with surrounding tissue. Indeed, senescent cell ablation dramatically inhibits physical deterioration in progeroid (age‐accelerated) mice. This review explores ways in which oxidative stress creates ageing‐associated cellular damage and triggers induction of the cell death/survival programs’ apoptosis, necrosis, autophagy and ‘necroapoptophagy’. The concept of ‘necroapoptophagy’ is presented here as a strategy for varying tissue oxidative stress intensity in ways that induce differential activation of death versus survival programs, resulting in enhanced and sustained representation of healthy functional cells. These strategies are discussed in the context of specialized mesenchymal stromal cells with the potential to synergize with telocytes in stabilizing engrafted progenitor cells, thereby extending periods of healthy life. Information and concepts are summarized in a hypothetical approach to suppressing whole‐organism senescence, with methods drawn from emerging understandings of ageing, gained from Cnidarians (jellyfish, corals and anemones) that undergo a unique form of cellular regeneration, potentially conferring open‐ended lifespans.     

Role of ageing and temperature in shaping reaction norms and fecundity functions in insects

The existing energy partitioning models assume that fecundity is constant throughout adult life. In insects, however, fecundity is a triangular function of time: after maturation, it initially sharply increases and after reaching its maximum it slowly declines as the mother ages. These models also fail to explain that empirical data generally indicate an increase in juvenile growth rate caused by improvement in food quality results in larger adults, whereas that caused by an increase in ambient temperature results in smaller adults. This ‘life history puzzle’ has worried many biologists for a long time. An energy‐partitioning model for insects is presented with soma and gonads as its components, which – contrary to other models – assumes ageing of soma. This model explains the triangular shape of the fecundity function, and also offers an explanation of the ‘life history puzzle’. The differential response in adult size to changes in food quality and temperature in nature may result from the differential responses of our model’s parameters to changes in these environmental parameters. Better food quality results in bigger adults, because food quality affects the assimilation rate, but not the rate of conversion of gonadal biomass into offspring, or the rate of senescence. In contrast, an increase in temperature speeds up all the processes. That is, temperature affects the assimilation rate, the conversion rate of gonadal biomass into offspring, and the rate of senescence equally. Therefore, an increase in temperature results in larger or smaller adults, depending on the shape of the senescence function.     

A day of systems and synthetic biology for non‐experts

From understanding ageing to the creation of artificial membrane‐bounded ‘organisms’, systems biology and synthetic biology are seen as the latest revolutions in the life sciences. They certainly represent a major change of gear, but paradigm shifts? This is open to debate, to say the least. For scientists they open up exciting ways of studying living systems, of formulating the ‘laws of life’, and the relationship between the origin of life, evolution and artificial biological systems. However, the ethical and societal considerations are probably indistinguishable from those of human genetics and genetically modified organisms. There are some tangible developments just around the corner for society, and as ever, our ability to understand the consequences of, and manage, our own progress lags far behind our technological abilities. Furthermore our educational systems are doing a bad job of preparing the next generation of scientists and non‐scientists.