Physical size,condition, and demography of chamois (Rupicapra rupicapra L.) in the Avoca River region,Canterbury, New Zealand

Abstract

The physical and demographic characteristics of chamois in the Avoca region are evaluated from 306 animals shot and autopsied between 1975 and 1978. These data are compared with published and unpublished information for chamois populations in Westland and Canterbury. Avoca chamois were large-framed, but weighed less than Westland chamois. The weight difference suggests better habitat condition and food resources for Westland animals, but the large skeletal size of Avoca chamois is unexplained.

High rates of juvenile mortality were caused by acute bacterial-pneumonia infections (Pasteurella). These deaths and other losses by natural causes were offset by the good breeding success of adult females so that stable population numbers were maintained.     

Determination of biotic aetiology of tapping panel dryness (TPD) syndrome of rubber tree (Hevea brasiliensis) by return-polyacrylamide gel electrophoresis (R-PAGE) technique

Tapping panel dryness (TPD) syndrome affecting rubber tree (Hevea brasiliensis) is known to reduce natural latex production. Its aetiology remains ambiguous despite long years of research. A low molecular weight RNA similar to viroid RNA was isolated from TPD-affected samples of rubber trees. In the present study, a modified return-polyacrylamide gel electrophoresis procedure was standardised. The viroid-like low molecular weight (LMW) RNA was found associated with leaf, bark and root tissues and rubber seedlings. The technique was employed to detect LMW RNA in different clones of rubber planted in different locations and in bud-grafted plants. The LMW RNA isolated from TPD-affected trees was found infectious on seedlings of tomato cv Pusa Ruby. The LMW RNA was reisolated from symptomatic tomato leaves but not from control plants. This is for the first time that a biotic agent, a viroid RNA, is found consistently associated with the syndrome. The technology developed can be useful to demonstrate the onset of TPD in untapped trees in the absence of other methods such as nucleic acid hybridisation.     

Efficacy of intercropping and harvest time modification for reducing field infestation of maize by Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Most management practices of Sitophilus zeamais Motschulsky, a field-to-post-harvest insect pest of cereals, have focused on post harvest control methods. This experiment was designed to investigate the potential of cropping system and modification of time of harvest to control S. zeamais. Intercropping and harvest time modification had significant (P < 0.05) effect on the number of S. zeamais emerging 42 days post-harvest. For the early harvest (15 weeks after planting (WAP)), the mean number of S. zeamais recorded from a maize monoculture (7.39) was significantly (P < 0.05) higher than the mean numbers of weevils emerging from a maize–soybean intercrop (2.31), but not significantly higher than the number recorded in maize–groundnut (3.87) intercrop. For the late harvest (18 WAP), the mean number of emerged adult observed in the maize–soybean intercrop (6.13) was significantly lower than the mean number of adult emerging from the monocrop maize (13.24). Maize–groundnut intercrop did not significantly reduce field infestation of S. zeamais compared with monocrop maize. Percentage weight loss observed in early harvested maize was significantly (P < 0.0001) lower than what was observed in late-harvested maize. Percentage weight loss was highest in stored maize harvested from monocrop maize plots for the early harvest, whereas intercropping maize with soybean reduced percentage weight loss when harvest was delayed.     

DISC1-related signaling pathways in adult neurogenesis of the hippocampus

Disrupted-in-schizophrenia 1 (DISC1) is a multifunctional scaffold protein which plays an important role in neurogenesis and neural development in the adult brain, especially in the dentate gyrus (DG) of the hippocampus. Accumulated research has unveiled the role of DISC1 in several aspects of neural development and neurogenesis, such as neuronal maturation, proliferation, migration, positioning, differentiation, dendritic growth, axonal outgrowth, and synaptic plasticity. Studies on the function of this protein have explored multiple facets, including variants and missense mutants in genetics, proteins interactivity and signaling pathways in molecular biology, and pathogenesis and treatment targets of major mental illness, and more. In this review, we present several signaling pathways discussed in recent research, such as the AKT signaling pathway, GABA signaling pathway, GSK3β signaling pathway, Wnt signaling pathway, and NMDA-R signaling pathway. DISC1 interacts, directly or indirectly, with these signaling pathways and they co-regulate the process of adult neurogenesis in the hippocampus.     

Low-Molecular-Weight DNA Replication Intermediates in Escherichia coli: Mechanism of Formation and Strand Specificity

Chromosomal DNA replication intermediates, revealed in ligase-deficient conditions in vivo, are of low molecular weight (LMW) independently of the organism, suggesting discontinuous replication of both the leading and the lagging DNA strands. Yet, in vitro experiments with purified enzymes replicating sigma-structured substrates show continuous synthesis of the leading DNA strand in complete absence of ligase, supporting the textbook model of semi-discontinuous DNA replication. The discrepancy between the in vivo and in vitro results is rationalized by proposing that various excision repair events nick continuously synthesized leading strands after synthesis, producing the observed LMW intermediates. Here, we show that, in an Escherichia coli ligase-deficient strain with all known excision repair pathways inactivated, new DNA is still synthesized discontinuously. Furthermore, hybridization to strand-specific targets demonstrates that the LMW replication intermediates come from both the lagging and the leading strands. These results support the model of discontinuous leading strand synthesis in E. coli.     

Computational Design of a Protein-Based Enzyme Inhibitor

While there has been considerable progress in designing protein–protein interactions, the design of proteins that bind polar surfaces is an unmet challenge. We describe the computational design of a protein that binds the acidic active site of hen egg lysozyme and inhibits the enzyme. The design process starts with two polar amino acids that fit deep into the enzyme active site, identifies a protein scaffold that supports these residues and is complementary in shape to the lysozyme active-site region, and finally optimizes the surrounding contact surface for high-affinity binding. Following affinity maturation, a protein designed using this method bound lysozyme with low nanomolar affinity, and a combination of NMR studies, crystallography, and knockout mutagenesis confirmed the designed binding surface and orientation. Saturation mutagenesis with selection and deep sequencing demonstrated that specific designed interactions extending well beyond the centrally grafted polar residues are critical for high-affinity binding.     

Anti-platelet activity of a three-finger toxin (3FTx) from Indian monocled cobra (Naja kaouthia) venom

A low molecular weight anti-platelet peptide (6.9 kDa) has been purified from Naja kaouthia venom and was named KT-6.9. MALDI-TOF/TOF mass spectrometry analysis revealed the homology of KT-6.9 peptide sequence with many three finger toxin family members. KT-6.9 inhibited human platelet aggregation process in a dose dependent manner. It has inhibited ADP, thrombin and arachidonic acid induced platelet aggregation process in dose dependent manner, but did not inhibit collagen and ristocetin induced platelet aggregation. Strong inhibition (70%) of the ADP induced platelet aggregation by KT-6.9 suggests competition with ADP for its receptors on platelet surface. Anti-platelet activity of KT-6.9 was found to be 25 times stronger than that of anti-platelet drug clopidogrel. Binding of KT-6.9 to platelet surface was confirmed by surface plasma resonance analysis using BIAcore X100. Binding was also observed by a modified sandwich ELISA method using anti-KT-6.9 antibodies. KT-6.9 is probably the first 3FTx from Indian monocled cobra venom reported as a platelet aggregation inhibitor.     

Overwintering strategy of endoparasitoids in Chilo suppressalis: a perspective from the cold hardiness of a host

Although parasitoids ultimately kill their host, koinobiont parasitoids must protect not only themselves but also their hosts against extreme environments. In this study, the parasitism rate of Chilo suppressalis Walker (Lepidoptera: Pyralidae) was investigated, and the average body weights, supercooling points, and concentrations of glycerol (acting as a cryoprotectant) in the hemolymph were compared between parasitized and non‐parasitized larvae. Five species of koinobiont endoparasitoids parasitized the overwintering C. suppressalis larvae and the total parasitism rate was 47.6% (n = 1 537). Average body weight of parasitized larvae was significantly lower than that of non‐parasitized larvae, and the parasitism rate of the lighter group (20–30 mg) was highest. The supercooling point of parasitized C. suppressalis larvae (?15.7 ± 0.3 °C) was significantly lower than that of the non‐parasitized larvae (?14.3 ± 0.2 °C). In addition, supercooling points were not correlated with body weights between parasitized and non‐parasitized larvae, indicating that cold hardiness of parasitized larvae was enhanced by endoparasitoids. Furthermore, the concentration of glycerol in the hemolymph was significantly higher in parasitized larvae (205.0 ± 7.1 μmol ml^?1) than in non‐parasitized larvae (169.8 ± 14.4 μmol ml^?1), which suggests that the mechanism that decreases the supercooling point of parasitized larvae was associated with glycerol. All these results indicated that the cold hardiness of parasitized C. suppressalis larvae was enhanced by their endoparasitoids, which benefitted overwintering endoparasitoids.     

Molecular weight distribution and functional group profiles of TEMPO-oxidized lyocell fibers

The effects of TEMPO-mediated oxidation, performed with NaClO, a catalytic amount of NaBr, and 2,2′,6,6′-tetramethylpiperidine-1-oxy radical (TEMPO), were studied on lyocell fibers by means of GPC using multiple detection and group-selective fluorescence labeling according to the CCOA and FDAM methodology. The applied method determines functional group content as a sum parameter, as well as functional group profiles in relation to the molecular weight of the cellulose fibers. Both the CHO and COOH profiles, as well as molecular weight alterations, were analyzed. A significant decrease in the average molecular weight was obtained during the first hour of TEMPO-mediated oxidation, but prolonged oxidation time resulted in no strong additional chain scission. Significant amounts of COOH groups were introduced in the high molecular weight fractions by the oxidation with higher concentrations of NaClO (2.42–9.67 mmol NaClO/g fiber) after modification times of 1 h or longer.