Correlation between the parameters of contingent negative variation and characteristics of variational pulsometry in Parkinsonian patients

In patients suffering from Parkinson's disease (PD), we analyzed correlations between the parameters of contingent negative variation (CNV) and data of variational pulsometry (according to the measurements of R-R ECG intervals). Studies were carried out on 35 patients (group PD), 49 to 74 years old, with the stage of disease of 1.5 to 3.0 according to the Hoehn-Yahr international classification. In the course of CNV recording (i.e., in the state of a certain functional loading), we observed significant negative correlations between the integral magnitude (area) of this potential and indices of variational pulsometry (RMSSD, SDNN, C. var, and HF) that characterize the intensity of parasympathetic (respiratory) influences on the cardiovascular system. In the control group, such correlations were absent. We found significant correlations between the autonomic balance, CNV magnitude, and stage of PD reflecting the level of generalization of the pathological process. In the subgroup of patients with the PD stage 1.5 to 2.0, significant changes in the mean values of indices of parasympathetic influences during recording of the CNV were not observed, while in another subgroup (the PD stage 2.5 to 3.0), these values increased significantly (P < 0.05 and P < 0.01). If the estimates of the PD stage were low, the CNV area demonstrated greater values (P < 0.01). The disturbance of coordination of muscle-to-muscle interactions in the PD group is, probably, an important factor responsible for parasympathetic dysregulation and suppression of the CNV generation. We found positive correlation between the intensity of parasympathetic influences in the course of CNV recording and the level of postural disorders (r = 0.37, P < 0.05). On the contrary, the CNV magnitude demonstrated a negative correlation with the intensity of these disorders (r = −0.36, P < 0.05), as well as with the level of postural instability (r = −0.55, P < 0.001). We hypothesize that alterations of the autonomic balance and the activity of those cerebral structures, which are responsible for the motor readiness, result, to a significant extent, from weakening of the activity of the noradrenergic system due to degenerative processes developing in cells of the locus coeruleus. The impairment of the latter structure, together with degeneration of neurons of the substantia nigra and a decrease in the level of nigro-striatal dopamine, underlies the pathomorphological pattern of PD. Neirofiziologiya/Neurophysiology, Vol. 40, No. 3, pp. 242–253, May–June, 2008.     

Insular avian adaptations on two Neotropical continental islands

Aim Most studies of avian insular adaptations have focused on oceanic islands, which may not allow characters that are insular adaptations to be teased apart from those that benefit dispersal and colonization. Using birds on continental islands, we investigated characters that evolved in situ in response to insular environments created by late Pleistocene sea level rise. Location Trinidad and Tobago and continental South America. Methods We weighed fresh flight muscles and measured museum skeletal specimens of seven species of birds common to the continental islands of Trinidad and Tobago. Results When corrected for body size, study species exhibited significantly smaller flight muscles, sterna and sternal keels on Tobago than on larger Trinidad and continental South America. Tobago populations were more ‘insular’ in their morphologies than conspecifics on Trinidad or the continent in other ways as well, including having longer bills, longer wings, longer tails and longer legs. Main conclusions We hypothesize that the longer bills enhance foraging diversity, the longer wings and tails compensate for the smaller pectoral assemblage (allowing for retention of volancy, but with a probable reduction in flight power and speed), and the longer legs expand perching ability. Each of these differences is likely to be related to the lower diversity and fewer potential predators and competitors on Tobago compared with Trinidad. These patterns of smaller flight muscles and larger bills, legs, wings and tails in island birds are not the results of selection for island dispersal and colonization, but probably arose from selection pressures acting on populations already inhabiting these islands.     

The role of nutrition on epigenetic modifications and their implications on health

Nutrition plays a key role in many aspects of health and dietary imbalances are major determinants of chronic diseases including cardiovascular disease, obesity, diabetes and cancer. Adequate nutrition is particularly essential during critical periods in early life (both pre- and postnatal). In this regard, there is extensive epidemiologic and experimental data showing that early sub-optimal nutrition can have health consequences several decades later.     

Avian life-history determinants of local extinction risk in a hyper-fragmented neotropical forest landscape

The fact that species vary in their vulnerability to extinction is well documented, but the reasons for these differences remain poorly understood. Why should some species/families/guilds decline rapidly with increasing anthropogenic disturbance, while others either tolerate or proliferate in disturbed habitats? We investigated the bird species composition in 31 primary forest patches of varying size in a region of the Amazonian 'Arc of Deforestation' and assessed which species life-history traits predisposed individual species to extinction. Medium-sized non-flocking canopy frugivores/ominvores of low primary forest dependence were least likely to go extinct in small patches, while small-bodied flock-following primary-forest-dependent terrestrial insectivores were most fragmentation sensitive. We found highly idiosyncratic relationships between the minimum size of forest patches occupied by different species and their territory size requirements estimated based on other Amazonian studies. This suggests that avian assemblages in forest fragments primarily comprise species that either have good dispersal abilities or are highly tolerant to the non-forest matrix, rather than those whose minimum spatial requirements can be met by the size of available forest fragments.     

Colonization and extinction of land planarians (Platyhelminthes,Tricladida) in a Brazilian Atlantic Forest regrowth remnant

Long-term assessments of species assemblages are valuable tools for detecting species ecological preferences and their dispersal tracks, as well as for assessing the possible effects of alien species on native communities. Here we report a 50-year-long study on population dynamics of the four species of land flatworms (Platyhelminthes, Tricladida, Terricola) that have colonized or become extinct in a 70-year-old Atlantic Forest regrowth remnant through the period 1955–2006. On the one hand, the two initially most abundant species, which are native to the study site, Notogynaphallia ernesti and Geoplana multicolor have declined over decades and at present do not exist in the forest remnant. The extinction of these species is most likely related with their preference for open vegetation areas, which presently do not exist in the forest remnant. On the other hand, the neotropical Geoplaninae 1 and the exotic Endeavouria septemlineata were detected in the forest only very recently. The long-term study allowed us to conclude that Geoplaninae 1 was introduced into the study area, although it is only known from the study site. Endeavouria septemlineata, an active predator of the exotic giant African snail, is originally known from Hawaii. This land flatworm species was observed repeatedly in Brazilian anthropogenic areas, and this is the first report of the species in relatively well preserved native forest, which may be evidence of an ongoing adaptive process. Monitoring of its geographic spread and its ecological role would be a good practice for preventing potential damaging effects, since it also feeds on native mollusk fauna, as we observed in lab conditions. Júlio Pedroni: Granted by CNPQ–Brazil.     

Promotion of indole alkaloid production in Catharanthus roseus cell cultures by rare earth elements

Production of the indole alkaloids, ajmalicine or catharanthine, in cell suspension cultures of Catharanthus roseus was enhanced by cerium (CeO₂ and CeCl₃), yttrium (Y₂O₃) and neodymium (NdCl₃). The yield of ajmalicine in these treated-cultures reached 51 mg l^–1 (CeO₂), 40 mg l^–1 (CeCl₃), 41 mg l^–1 (Y₂O₃) and 49 mg l^–1 (NdCl₃) while catharanthine production reached to 36 mg l^–1 (CeO₂) and 31 mg l^–1 (CeCl₃). A major portion of increased alkaloids was released into medium in these treatments. But Sm₂O₃, SmCl₃, La₂O₃, LaCl₃, complex of chromium (III)-titanium (IV) and NaSeO₄ treatments had little effect on alkaloid production of C. roseus cell cultures.     

喜树叶、枝水溶性糖提取的研究

用正交实验结果作方差分析表明：溶剂用量对试验结果有较显著的影响（a=0.10)，提取温度对试验结果也有较大的影响，而提取时间对试验结果的影响不显著。喜树叶中水溶性糖的提取最优方案是A3C2B3，即溶剂用量为60ml，提取温度80℃，提取时间60min；喜树叶水溶性糖的提取最优方案是A2C2B1，即溶剂用量为40ml，提取温度80℃，提取时间20min。通过对喜树叶与枝的成对比较分析，叶与枝的水溶性糖含量无显著差异。     

Interactions of target population size,population parameters,and program management on viability of captive populations

When established conservation programs expand and evolve, management practices may become inconsistent with program goals. In the past decade, the American Zoo and Aquarium Association expanded species conservation programs by increasing the number of Species Survival Plans (SSP) and establishing more than 300 new Population Management Plan (PMP) programs. However, limited space in captive breeding facilities forces a competition among SSPs and less intensively managed PMPs. Regional Collection Plans establish priorities and allocate space accordingly by setting target population size for each species; species of high conservation priority (SSPs) are allocated space at the expense of lower priority species (PMPs). Because population size and genetic composition interact to impact population viability, target population size is a significant factor to a population’s prospects for long‐term survival. We examined four population parameters (current population size, target population size, current gene diversity, and mean generation time) for 46 mammalian SSPs and 17 PMPs. Relative to SSPs, PMPs combine smaller current and target population sizes, lower levels of current gene diversity, and shorter mean generation times than SSPs. Thus, the average PMP population can expect to lose gene diversity more rapidly than the average SSP population. PMPs are projected to lose 10% or more of their founding gene diversity, within only 2 years. In contrast, the average SSP population is projected to lose 10% in 40 years. Populations with small current or target population sizes require intensive management to avoid extinction. More intensive genetic management of populations typically designated as PMPs, through recruitment of potential founders and equalization of founder representation, could increase gene diversity and improve viability. Less rigorous population management should be reserved for populations whose long‐term survival is either secure or that can be readily replenished from the wild. Because PMP populations need intense genetic management similar to that currently in effect for SSPs, there should be neither a management‐level distinction between programs nor an arbitrary difference in space allocated to programs. Zoo Biol 20:169–183, 2001. © 2001 Wiley‐Liss, Inc.