Sensitivity of managed boreal forests in Finland to climate change, with implications for adaptive management

This study investigated the sensitivity of managed boreal forests to climate change, with consequent needs to adapt the management to climate change. Model simulations representing the Finnish territory between 60 and 70 degrees N showed that climate change may substantially change the dynamics of managed boreal forests in northern Europe. This is especially probable at the northern and southern edges of this forest zone. In the north, forest growth may increase, but the special features of northern forests may be diminished. In the south, climate change may create a suboptimal environment for Norway spruce. Dominance of Scots pine may increase on less fertile sites currently occupied by Norway spruce. Birches may compete with Scots pine even in these sites and the dominance of birches may increase. These changes may reduce the total forest growth locally but, over the whole of Finland, total forest growth may increase by 44%, with an increase of 82% in the potential cutting drain. The choice of appropriate species and reduced rotation length may sustain the productivity of forest land under climate change.     

How does interferon inhibit tumour growth?

Interferon can inhibit tumour growth in experimental animals and in some patients with benign and malignant tumours. There is experimental evidence to suggest that several mechanisms may be involved: a direct effect on the tumor or an indirect effect via the host, or both. Thus, interferon may slow the rate of tumour cell multiplication and this may lead to cell death. Interferon may induce changes in the cell surface rendering tumour cells more sensitive to host defence mechanisms. Interferon may induce reversion in the phenotype of tumour cells. Interferon may stimulate specific and non-specific humoral and cellular host mechanisms. The relative importance of these different effects of interferon may vary depending on the host and the particular tumour.     

Reactive oxygen species and airway inflammation

Reactive oxygen species may be generated by several inflammatory cells which participate in airway inflammation and their production may be increased in asthma. Oxygen metabolites may contribute to the epithelial damage which is characteristic of asthmatic airways and may activate cells such as mast cells in the airway mucosa. Reactive oxygen species may cause bronchoconstriction, mucus secretion, have effects on airway vasculature, and may increase airway responsiveness. The role of reactive oxygen species in airway disease has been largely neglected, but appears to be an important area for future study. It is also possible that antioxidant defenses may be defective in asthma. If reactive oxygen species participate in the inflammatory response in airway disease, then radical scavengers or antioxidants could play a useful role in therapy.     

Cultural Variation—Nutritional and Clinical Implications

Cultural variation may play an important role in human nutrition and must be considered in either clinical or public health intervention particularly in areas with large immigrant populations. Acculturative and environmental change influence the food habits and health of transitional groups. Nutritional assessment may be complicated by cultural variation. The relationship between ethnicity and nutrition may be of evolutionary significance. Food beliefs may have beneficial or detrimental effects on health status. The study of acculturating populations may elucidate the pathogenesis of nutrition-related chronic diseases. Appreciation of the interaction of culture and nutrition may be of benefit to physicians and nutritionists in clinical practice and to those concerned with the prevention of nutrition-related chronic diseases.     

Non-replication and inconsistency in the genome-wide association setting

Non-replication and inconsistency had been common features in the search for common variants of candidate genes affecting the risk of complex diseases. They may continue to require attention in the current era, when massive hypothesis-free testing of genetic variants is feasible. An empirical evaluation of the early experience with genome-wide association (GWA) studies suggests several examples where proposed associations have failed to be replicated by subsequent investigations. Non-replication and inconsistency is defined here in the framework of cumulative meta-analysis. Ideally, associations exist, GWA finds them, and subsequent investigations should replicate them. However, a number of other possibilities need to be considered. No common genetic variants may associate with the phenotype of interest and GWA may find nothing; or associations may exist, but GWA may miss them. Associations that do not exist may be falsely selected by the GWA and subsequent studies may appropriately refute them or falsely replicate them. Finally, GWA may find true associations that are nevertheless falsely non-replicated in the subsequent studies; or associations may be genuinely inconsistent across study populations. A list of options is presented for consideration in each of these scenarios.     

THE CLINICAL PICTURE OF PANCREATIC INSUFFICIENCY

Minor degrees of pancreatic insufficiency may go unrecognized. There is a paucity of symptoms and physical findings in mild and moderate degrees of insufficiency and in such circumstances laboratory methods are necessary to determine the presence of insufficiency. The clinical picture when insufficiency is well established may be characterized by loss in weight; vague indigestion; voluminous, light-colored, glistening stools in which fat globulets may be seen; changes in the concentration of pancreatic enzymes in the blood indicative of lowered pancreatic function; diminished amounts of pancreatic enzymes in the duodenal juice, and the related poor digestion of fat and protein in the food. Lowered tolerance of carbohydrate, as found in diabetes mellitus, may or may not be present. The location and character of the disease in the pancreas causing the insufficiency may or may not be apparent.     

Potential vulnerabilities of neuronal reward, risk, and decision mechanisms to addictive drugs

How do addictive drugs hijack the brain's reward system? This review speculates how normal, physiological reward processes may be affected by addictive drugs. Addictive drugs affect acute responses and plasticity in dopamine neurons and postsynaptic structures. These effects reduce reward discrimination, increase the effects of reward prediction error signals, and enhance neuronal responses to reward-predicting stimuli, which may contribute to compulsion. Addictive drugs steepen neuronal temporal reward discounting and create temporal myopia that impairs the control of drug taking. Tonically enhanced dopamine levels may disturb working memory mechanisms necessary for assessing background rewards and thus may generate inaccurate neuronal reward predictions. Drug-induced working memory deficits may impair neuronal risk signaling, promote risky behaviors, and facilitate preaddictive drug use. Malfunctioning adaptive reward coding may lead to overvaluation of drug rewards. Many of these malfunctions may result in inadequate neuronal decision mechanisms and lead to choices biased toward drug rewards.     

Dual regulation of microglia and neurons by Astragaloside IV‐mediated mTORC1 suppression promotes functional recovery after acute spinal cord injury

Inflammation and neuronal apoptosis contribute to the progression of secondary injury after spinal cord injury (SCI) and are targets for SCI therapy; autophagy is reported to suppress apoptosis in neuronal cells and M2 polarization may attenuate inflammatory response in microglia, while both are negatively regulated by mTORC1 signalling. We hypothesize that mTORC1 suppression may have dual effects on inflammation and neuronal apoptosis and may be a feasible approach for SCI therapy. In this study, we evaluate a novel inhibitor of mTORC1 signalling, Astragaloside IV (AS‐IV), in vitro and in vivo. Our results showed that AS‐IV may suppress mTORC1 signalling both in neuronal cells and microglial cells in vitro and in vivo. AS‐IV treatment may stimulate autophagy in neuronal cells and protect them against apoptosis through autophagy regulation; it may also promote M2 polarization in microglial cells and attenuate neuroinflammation. In vivo, rats were intraperitoneally injected with AS‐IV (10 mg/kg/d) after SCI, behavioural and histological evaluations showed that AS‐IV may promote functional recovery in rats after SCI. We propose that mTORC1 suppression may attenuate both microglial inflammatory response and neuronal apoptosis and promote functional recovery after SCI, while AS‐IV may become a novel therapeutic medicine for SCI.     

Systemic Effects of Non-Endocrine Tumours

Tumours of non-endocrine origin may exert deleterious effects by elaborating active principles which disturb body regulation. Systemic manifestations are fairly common with neoplasms of the lung, kidney, gastro-intestinal tract and thymus. The secretion of these tumours may have a known chemical structure (serotonin), may present hormone-like action (parathormone, antidiuretic hormone, insulinoid), or have well-defined biological properties (erythropoietin, gastrin-like principle). Tumours may stimulate endocrine glands by an unknown mechanism, producing disorders such as Cushing''s syndrome, hypercalcemia, gynecomastia and hypoglycemia. Thymomas may be associated with autoimmune diseases. Tumours may extensively utilize or excrete some metabolite (glucose) or electrolyte (Na or K). Awareness of the systemic effects of various neoplasms may lead to an early diagnosis and proper treatment of these manifestations.     

Biological interactions among extant and fossil clonal organisms

Biological interactions among clonal marine organisms are an important aspect of their behavior and are important in the construction of biological reefs. The interactions addressed here are among crustose and erect coralline algae, sponges, corals, and bryozoans, and may involve clones of the same species (conspecific), or different species (heterospecific). Conspecific interactions may be either between modules or clones that are produced asexually from one propagule, genetically identical, or between clones that are sexually produced from two or more propagules that may or may not be genetically identical. Juxtaposed genetically identical clones generally fuse whereas non-identical clones may or may not fuse, depending on their relatedness and histocompatibility. Most heterospecific clonal interactions are spatially competitive and result in overgrowths or stand-offs. Clone fission/fragmentation may occur as a result of biotic or abiotic processes that initially degrade but may eventually restore or even enhance ability to gain space and/or nutrients. Self-overgrowths also occur, usually over dead, diseased, or senescent parts of the same clone.     

Possible causes of fever after interferon administration

Several factors can be responsible for the febrile response evoked by interferon (IF) administration in man. Since different cells and inducers are used for production of IF, the pyrogenic substance may not always be the same. Leucocyte IF (LeIF) may contain endogeneous pyrogen (EP), fibroblast IF (FIF) may contain heterogeneous proteins and/or EP, and lymphoblastoid IF (LyIF) may contain a factor released by the transformed lymphocyte able to induce, in vivo, the release of EP from leucocytes. Finally, IF may be intrinsically pyrogenic and, if this is the case, until homogeneous IF is used, it may potentiate the action of the pyrogenic contaminants.     

Injuries caused by garfish in Papua New Guinea.

Garfish, which are found in the Indo-Pacific Ocean areas, have a long, spear-like beak with two marrow jaws and small pointed teeth. They often make sudden leaps while swimming, particularly when attracted by bright lights. In Papua New Guinea people often fish from canoes using a light at night, and serious injuries may be caused by a fish jumping and its beak piercing part of the body. The surface wound may appear deceptively small and innocent, but if the wound is on the chest or abdomen the beak may have penetrated sufficiently deeply to cause internal injuries, and death may result. Patients may have to be admitted to hospital for removal of the beak, which may remain embedded in a limb.     

Partnership

Individuals are called partners when it is in their best interest to help each other, if by doing so they increase the probability of being together in the future when, for similar reasons, they will continue to help each other. Kinsmen or individuals who often face (hedonic) situations in which helping is the dominating strategy are committed to help each other. Partnership may develop among them since the loss of the other means the loss of a guaranteed helper. Thus, they may be willing to take additional risks to help each other. Partnership may occur among unrelated individuals and with no hedonic situations. Partnership creates bonds between partners which may be much stronger than those between kinsmen; an individual may take more risks for his partner than he will ever take for a kin. Partnership may evolve without the sophistication and memory required for reciprocation altruism. Although kin selection, partnership and reciprocation are likely to appear fused as the causes for altruism, we argue that it may be possible to distinguish between them in some situations. We show that as the partners get older partnership may become less important to them. We also show that like cooperation, and for analogous reasons, malice may evolve among partners so that each will be willing to take additional risks in order to eliminate the other.     

Paraneoplastic Syndromes

Neoplasms can produce a variety of remote effects on the host; these are referred to as paraneoplastic syndromes. The syndromes may affect any of the systems of the body, may precede or follow the diagnosis of the underlying neoplasm, and may or may not parallel the course of the neoplasm in severity. The diagnosis of and therapy for these syndromes can be challenging to a physician, but successful therapy may bring about worthwhile relief for the patient. In addition, the syndromes and the substances that cause them are sometimes useful in diagnosing and in following the course of certain neoplasms. Perhaps of greater importance, study of these remote effects of neoplasia may shed light on the nature of the neoplastic process itself.     

Arms races between and within species.

An adaptation in one lineage (e.g. predators) may change the selection pressure on another lineage (e.g. prey), giving rise to a counter-adaptation. If this occurs reciprocally, an unstable runaway escalation or 'arms race' may result. We discuss various factors which might give one side an advantage in an arms race. For example, a lineage under strong selection may out-evolve a weakly selected one (' the life-dinner principle'). We then classify arms races in two independent ways. They may be symmetric or asymmetric, and they may be interspecific or intraspecific. Our example of an asymmetric interspecific arms race is that between brood parasites and their hosts. The arms race concept may help to reduce the mystery of why cuckoo hosts are so good at detecting cuckoo eggs, but so bad at detecting cuckoo nestlings. The evolutionary contest between queen and worker ants over relative parental investment is a good example of an intraspecific asymmetric arms race. Such cases raise special problems because the participants share the same gene pool. Interspecific symmetric arms races are unlikely to be important, because competitors tend to diverge rather than escalate competitive adaptations. Intraspecific symmetric arms races, exemplified by adaptations for male-male competition, may underlie Cope's Rule and even the extinction of lineages. Finally we consider ways in which arms races can end. One lineage may drive the other to extinction; one may reach an optimum, thereby preventing the other from doing so; a particularly interesting possibility, exemplified by flower-bee coevolution, is that both sides may reach a mutual local optimum; lastly, arms races may have no stable and but may cycle continuously. We do not wish necessarily to suggest that all, or even most, evolutionary change results from arms races, but we do suggest that the arms race concept may help to resolve three long-standing questions in evolutionary theory.     

Meta-analysis and its problems.

Including all relevant material--good, bad, and indifferent--in meta-analysis admits the subjective judgments that meta-analysis was designed to avoid. Several problems arise in meta-analysis: regressions are often non-linear; effects are often multivariate rather than univariate; coverage can be restricted; bad studies may be included; the data summarised may not be homogeneous; grouping different causal factors may lead to meaningless estimates of effects; and the theory-directed approach may obscure discrepancies. Meta-analysis may not be the one best method for studying the diversity of fields for which it has been used.     

Hormone multifunctionalities: a theory of endocrine signaling, command and control

A theory is presented outlining how organisms can function and benefit from multifunctionality of hormones in order to enhance greatly the information-carrying potential of endocrine signaling. Hormones are produced continuously as micropulses, and intermittently as larger pulses. It is generally believed that micropulses generate fluctuating basal hormone concentrations, which may consistently elicit particular responses among diverse variables. Evidence is discussed suggesting that in contrast to the hormone micropulses, the larger endogenous hormone pulses may elicit responses which may differ from one pulse to another and may therefore serve different physiological functions. In this paper we postulate that an endogenous hormone pulse is a specific form of a multisignal message that serves a certain physiological function. Different pulses of a hormone may be signals of diverse multisignal messages that serve different functions. A multisignal message may elicit congruous responses by selectively enhancing some actions and suppressing other actions of the component signals. Various roles of signals of multisignal messages are discussed, as well as processes that may be involved in the diversity and selectivity of actions of different pulses of a hormone. Hormones also are converted into other hormones; we analyze how precursor and derived hormones may function independently of each other, and how precursor hormones may give rise to permissive effects. Mechanisms involved in therapeutic and adverse effects of hormone administrations are analyzed, and a strategy is suggested for developing more selective hormonal therapies.     

Hunting G-quadruplexes

Whilst DNA spends much of its time in the double-stranded form, frequently in storage, wrapped around histones and packaged as chromatin, it can also form other complex structures, which may play a role in natural regulation and gene control. These alternative structures therefore also present an interesting novel series of targets for artificial intervention, and so may lead to novel therapeutics. In this review, I describe the current understanding of how genomic and bioinformatics studies may be used to understand the roles that one such structure, the four-stranded guanine-rich G-quadruplex, may play in the genome, and outline how these may be considered as targets for intervention. I will also describe recent work looking at RNA G-quadruplexes, and the biological roles they may play.     

Irregularities in the early development of the Drosophila Melanogaster egg

Summary Polyspermy is normally present in the Drosophila egg.Extreme polyspermy may lead to disturbances which may prevent the egg from further development.Polar body formation may be disorganized by supernumerary sperms.Supernumerary sperms may form unipolar, bipolar and multipolar spindles.In rarer cases sperms will enter into normal spindles and form multipolar spindles. In some cases such interference seems to adjust itself to the original bipolar condition and division figures with the polyploid number of chromosomes will result. Either by the conjugation of two sperms, or by dimegaly, or by the doubling of chromosomes of a single sperm, supernumerary nuclei may develop. The origin of certain mosaics and gynandromorphs may be explained on this basis.     

Valvular obstruction of the nasal airway.

Valvular nasal obstruction may occur in the postoperative rhinoplasty patient. One may anticipate a dropping of the tip, from residual redundant or inelastic skin, in some older patients with long noses. Measures to correct (or avoid) this may be undertaken at the time of the primary rhinoplasty. However, an overcorrection may be necessary if there is much redundant skin. Discretion may indicate the need for a secondary procedure. Lateral wall valving is unusual-but it may occur in the long, high, thin nose (where a suggestion of this action may be observed preoperatively). Maintenance of continuous cartilage along the alar rim, at the time of alar cartilage resection, appears to be important in prevention of postoperative valvular obstruction in these few patients.