Nightmares, life stress, and anxiety: An examination of tension reduction.

Do nightmares increase or decrease anxiety? Theoretical views of nightmares suggest that nightmares play out stressful events, decathecting their energy. A more pragmatic view suggests that nightmares that result in waking distress add to the burden of anxiety. The current study investigates whether negative life events are associated with an increase or decrease in anxiety attributable to nightmares in 624 adolescents aged between 12 and 19. The results indicate no support for a tension reduction hypothesis. There seems no relief from anxiety if a person reports nightmares, and the stronger the distress of waking (from nightmares), the more likely a person is to report anxiety, controlling for life events and the distress associated with life events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antibiotics LL-Z1272 identified as novel inhibitors discriminating bacterial and mitochondrial quinol oxidases

To counter antibiotic-resistant bacteria, we screened the Kitasato Institute for Life Sciences Chemical Library with bacterial quinol oxidase, which does not exist in the mitochondrial respiratory chain. We identified five prenylphenols, LL-Z1272β, γ, δ, ? and ζ, as new inhibitors for the Escherichia coli cytochrome bd. We found that these compounds also inhibited the E. coli bo-type ubiquinol oxidase and trypanosome alternative oxidase, although these three oxidases are structurally unrelated. LL-Z1272β and ? (dechlorinated derivatives) were more active against cytochrome bd while LL-Z1272γ, δ, and ζ (chlorinated derivatives) were potent inhibitors of cytochrome bo and trypanosome alternative oxidase. Thus prenylphenols are useful for the selective inhibition of quinol oxidases and for understanding the molecular mechanisms of respiratory quinol oxidases as a probe for the quinol oxidation site. Since quinol oxidases are absent from mammalian mitochondria, LL-Z1272β and δ, which are less toxic to human cells, could be used as lead compounds for development of novel chemotherapeutic agents against pathogenic bacteria and African trypanosomiasis.     

Specific expression of Neu2 type B in mouse thymus and the existence of a membrane-bound form in COS cells

Neu2 mRNA from the mouse thymus, as we have reported [K. Kotani, A. Kuroiwa, T. Saito, Y. Matsuda, T. Koda, S. Kijimoto-Ochiai, Cloning, chromosomal mapping, and characteristic 5′-UTR sequence of murine cytosolic sialidase, Biochem. Biophys. Res. Commun. 286 (2001) 250-258], has a novel sequence at the 5′ terminus that shows the ability to encode 6 extra amino acids in the N-terminus than that of the muscle. In this paper, we analyzed the cDNA and EST database and found the five types of alternative splicing of Neu2 mRNA: A, B, C, D and N. We studied the expression of these types in the immune tissues and found that the thymus expressed only type B. We constructed 2 types of plasmid that encode long (B) or short (C) form of Neu2 protein, and transfected them into COS7 cells to study them under the same conditions. We found that 30-40% of the both forms of Neu2 activity was located in the crude membrane-fraction, and hydrolyzed ganglioside effectively, while both soluble fraction showed particular behavior with substrate specificity. Microscopic study by active staining with X-NANA showed that they located not only in the cytoplasm but also in areas surrounding the nucleus and in the peripheral ruffled spot.     

Abiotic influences on embryo growth: statoliths as experimental tools in the squid early life history

Statolith size and growth was used to determine the influence of abiotic factors on the growth of Loligo vulgaris and Sepioteuthis australis embryos. Recently spawned egg masses collected from the field were incubated in the laboratory under different levels of light intensity, photoperiod, or short periods of low salinity (30‰). Double tetracycline staining was used to follow statolith growth. In L. vulgaris constant light conditions produced significantly slower growth in the embryonic statoliths and embryos held at summer photoperiod had slower statolith growth than those held at winter photoperiods. However once they hatched out there was no evidence that photoperiod affected statolith growth. After hatching, in all photoperiods statolith growth rates decreased in comparison with late embryonic rates. In S. australis embryos, differences between the high and medium light intensities for summer and intermediate photoperiods were found, suggesting that under summer incubation temperature, longer daylengths at medium light intensity favoured higher statolith growth for this species. In comparison to controls, slower statolith growth in S. australis embryos due to low salinity only occurred when exposed for 72 h. Comparison with previous studies indicates that temperature seems to be the main abiotic factor influencing statolith growth during early stages, however, interactions among all abiotic factors needs to be determined as well as the unknown influence of other isolated factors, e.g., oxygen concentration within the egg mass.     

Using the composite variables of reproductive morphology, histology and steroid hormones to determine age and size at sexual maturity for the thorny skate Amblyraja radiata in the western Gulf of Maine

Age at size was linked to sexual maturity in 77 male and 93 female thorny skates Amblyraja radiata from the western Gulf of Maine using three criteria: 1) gross reproductive morphology, 2) histology and 3) steroid hormone concentrations. Age-bias plots and the coefficient of variation from vertebral band counts suggested that the ageing method represented a non-biased and precise approach to the age assessment of A. radiata . Maturity ogives for males, based on data gathered for clasper length, circulating testosterone concentrations and proportion of mature spermatocysts within the testes, predicted that 50% maturity occurred at a total length ( L _T) of 865 mm and c. 10·90 years of age. For females, maturity ogives, based on data gathered for ovary mass, shell gland mass, follicle size and circulating oestradiol concentrations, predicted that 50% maturity occurred at 875 mm L _T and c. 11·00 years of age. Collectively, the results suggest that analysis of several contemporaneous reproductive variables offers an accurate determination of sexual maturity in the thorny skate.     

Evolved psychology in a novel environment

The human “environment of evolutionary adaptedness” can only be inferred indirectly. In contrast, the behavior of some nonhuman animals can be compared among “natural” and various altered environments. As an example, male immigration tactics in unprovisioned versus provisioned macaque (Macaca) populations are compared using Tooby and Cosmides’s (1992) framework for evolutionary functional analysis. In unprovisioned populations, social groups contain few males, and immigrant male takeovers of alpha rank occur frequently. In provisioned populations, groups contain many males, and males almost invariably enter social groups at very low rank and rise in rank only as more dominant males emigrate or die. Male conformity to the “seniority rule” is hypothesized to represent the behavioral output of an evolved decision-making algorithm (psychological mechanism) that takes into account (1) the net payoff of each rank in the dominance hierarchy and (2) the power of male group size as a predictor of the likelihood of successful immigrant takeover. Joseph H. Manson is Assistant Professor of Anthropology at the University of California, Los Angeles. His research interests are social relationships in nonhuman primates and humans, with particular emphases on mate choice, courtship tactics, intrasexual competition, and (currently) mother-infant relationships and infant handling. He has conducted fieldwork on rhesus macaques at Cayo Santiago and white-faced capuchins in Costa Rica.     

Parasite influences on host life history: Echinostoma revolutum parasitism of Lymnaea elodes snails

Using field surveys and experimental infections, we investigated the influence of a trematode parasite on life history traits of adult Lymnaea elodes snails. We found that parasitism significantly affected the growth, fecundity, and survival of host snails. Within five of the six natural L. elodes populations we sampled, shell length of echinostome-infected hosts was significantly greater than for uninfected conspecifics. Furthermore, we show that gigantism occurs among experimentally infected snails due to an accelerated growth rate and size-selective mortality following an Echinostoma revolutum infection. The fecundity of infected snails sharply decreased beginning at 3 weeks post exposure (PE) and all egg production eventually ceased for most hosts by 5–6 weeks PE. Energy constraints, imposed by parasite development, alter the host energy budget. Early in the infection, parasite depletion of host energy reserves reduces host reproduction, but sufficient resources remain to allow accelerated host growth. Mortality was increased among host snails at two distinct stages: shortly after exposure and several weeks after cercariae were first released. We did not observe tissue degradation in snails during the first 4 weeks after exposure to the parasite, but destruction of host tissues was noted among snails dying later in the infection. Received: 5 September 1997 / Accepted: 19 November 1997     

Reproductive biology of the endemic goby, Lentipes concolor, from Makamaka'ole Stream, Maui and Waikolu Stream, Moloka'i

Constant pressure in Hawai'i to use limited freshwater resources has resulted in increasing concern for the future of the native stream fauna. Hawaiian freshwater gobies have an amphidromous life cycle with a marine larva period and require streams which flow continuously to the ocean for the critical reproductive periods and during recruitment. As such, the stream fauna is particularly sensitive to any anthropogenic perturbations which disrupt the continuity of stream flows. The objective of this 2-year study was to compare the life cycles of the goby, Lentipes concolor, from a heavily diverted stream on Moloka'i and a relatively undisturbed stream on Maui. In Makamaka'ole Stream, Maui, the population of L. concolor was reproductively active all year with females potentially spawning 2–3 times annually. The timing of spawning did not occur consistently during the wet or dry season but coincided with high stream flow conditions regardless of time-of-year. In Waikolu Stream, Moloka'i, the reproductive pattern was more variable with the number of reproductively active females ranging from 0% to 100%. In general the number of eggs was greater and egg size smaller for female L. concolor in Waikolu Stream than in Makamaka'ole Stream. However, female reproductive condition of L. concolor from Maui was consistently higher than from fish on Moloka'i. Reproduction of L. concolor in Makamaka'ole Stream was correlated with the seasonal pattern of flow rates with peaks in female reproductive condition associated with periods of elevated discharge. No correlation between reproduction and discharge occurred in Waikolu Stream. There were considerable differences between the magnitude of discharge in the two streams. Waikolu Stream experienced prolonged periods of extremely low flows which have become common since the Moloka'i Irrigation System began diverting water from the stream in 1960. In Makamaka'ole Stream, L. concolor was capable of reproducing throughout the year and adjusting fecundity in response to stream flow conditions. In contrast, the population in Waikolu Stream appeared to have a ‘boom or bust’ reproductive pattern; the population had reduced or no reproduction when stream flow conditions reached extreme low levels, but the population succesfully reproduced during higher flow months. The diversion structure in Waikolu Stream has dampened the natural seasonal discharge cycle, exacerbated natural low flow conditions, and increased the likelihood of prolonged periods of extremely low flow. Stream management practices in the Hawaiian Islands must take into account the complex life cycles and sensitivity to variable stream flow conditions of the native fauna. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Large Isoform of Myelin-Associated Glycoprotein Is Scarcely Expressed in the Quaking Mouse Brain

Two polypeptide isoforms of myelin-associated glycoprotein (MAG) with molecular masses of 72 and 67 kDa are produced by alternative splicing of the exon 12 portion. Our previous work has demonstrated that in the quaking mouse brain this alternative splicing is lacking and that the mRNA coding the large MAG isoform (L-MAG) is scarcely expressed, whereas that of small MAG isoform (S-MAG) is overexpressed. In the present study, we prepared antisera specific to the S-MAG and L-MAG amino acid residues, respectively. Immunoblots showed that the L-MAG band was scarcely detectable in the quaking mouse brain, whereas the S-MAG band had an apparently higher molecular mass than in the normal control. Our immunohistochemical study also showed that L-MAG was scarcely stained in the quaking mouse brain. These results seemed to reflect a reduction in content of L-MAG mRNA and abnormal glycosylation in the quaking mouse brain.     

Herbarium collections and field data-based plant diversity maps for Burkina Faso

A map of plant species diversity in Burkina Faso is presented based on field observations and specimen data from the Ouagadougou University Herbarium (OUA) and the Herbarium Senckenbergianum (FR). A map of collecting intensity and field observations illustrates centres of botanical research activities in Burkina Faso. To overcome problems associated with biased sampling intensity, distributions of species have been modelled and extrapolated to maps of vascular plant diversity, life forms and diversity of four selected families (Poaceae, Cyperaceae, Dioscoreaceae and Rubiaceae). The area of most intensive collection and observation is around Gorom‐Gorom and Fada N’Gourma. Modelled diversity generally increases towards the south, as does the proportion of phanerophytes, lianas and hemicryptophytes, while the opposite trend is observed for therophytes. Poaceae diversity is highly correlated with total vascular plant diversity, making the family especially suitable as an indicator for overall plant diversity. Cyperaceae are rather evenly distributed throughout the country, Dioscoreaceae are restricted to the Sudanian Zone. Rubiaceae have their highest diversities in the very south. Our approach can be transferred to areas with a similar database, certainly to other areas within West Africa. Future research should focus on distribution data for rare species, enabling our approach to evaluate the West African system of protected areas.