Migration sources and pathways of the pest species Sogatella furcifera in Yunnan,China, and across the border inferred from DNA and wind analyses

The migration sources and pathways of Sogatella furcifera (Horváth) in topologically complex regions like Yunnan, China, and adjacent montane areas have long been a challenging task and a bottleneck in effective pest forecast and control. The present research reinvestigated this issue using a combination of mtDNA and long‐term historical wind field data in an attempt to provide new insights. Genetic analyses showed that the 60 populations of S. furcufera collected across Myanmar, Thailand, Laos, Vietnam, Yunnan, Guizhou, and Sichuan lack genetic structure and geographic isolation, while spatial analysis of haplotype and diversity indices discovered geographic relevance between populations. Migration rate analysis combined with high‐resolution 10‐year wind field analysis detected the following migration sources, pathways, and impacted areas which could explain the outbreak pattern in Yunnan. (a) Dominating stepwise northward migrations originated from northern Indochina, southern Yunnan, and central‐eastern Yunnan, impacting their northern areas. (b) Concurring summer–autumn southward (return) migration originated from nearly all latitude belts of Sichuan and Yunnan mainly impacting central and southern Yunnan. (c) Regular eastward and summer–autumn westward migrations across Yunnan. The northward migration reflects the temporal rhythm of gradual outbreaks from the south to the north in a year, while the return migration may explain the repeated or very severe outbreaks in the impacted areas. To form a better pest forecast and control network, attention must also be paid to the northern part of Yunnan to suppress the impact of return migration in summers and autumns.     

Species-Specific Mechanisms of Neuron Subtype Specification Reveal Evolutionary Plasticity of Amniote Brain Development

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Changes occurring in cortical NO release and brain NO-synthases during a paradoxical sleep deprivation and subsequent recovery in the rat

Variations occurring in cortical nitric oxide (NO) release were analysed with a voltametric method in rats (i) placed in control conditions, (ii) while being paradoxical sleep deprived (PSD), or (iii) recovering from a PSD. Activities of neuronal (nNOS) and inducible (iNOS) NO-synthases as well as nNOS expression were also determined in several brain regions. In baseline conditions, circadian variations in nNOS expression and activity were maximal during the dark period and minimal during the light one for all the structures analysed (frontal cortex, pons and medulla). In the same way, cortical NO release occurred through a circadian rhythm exhibiting maxima and minima during dark and light periods, respectively. In the same experimental conditions, iNOS activity did not exhibit time-dependent changes. The correlative changes observed in baseline conditions between NO release, nNOS expression and activity within the frontal cortex were disrupted during PSD and subsequent recovery. Still again, iNOS activity remained unchanged. Results obtained point out that the tight coupling existing in control conditions between nNOS expression-activity and NO release is disrupted by a PSD and remains affected during the subsequent 24 h recovery. Their significance is discussed.     

突触后钙通路有助于视锥与L型水平细胞间的突触可塑性

我们实验室以前发现,视网膜视锥与亮度型水平细胞（luminosity—type horizontal cell,LHC）之间的突触传递效率具有可塑性。重复性刺激红敏视锥增加了LHC对红光的超极化反应幅度,而且这种增强作用是可逆的。在本文中,我们运用细胞内记录技术和药理学分析的方法来考察重复性红光刺激引起的反应增强的可能机制。当通过胞内注射Ca^2＋的螯合剂EGTA来降低LHC内的Ca^2＋浓度后,重复性红光引起的反应增强被抑制,提示突触后钙信号是反应增强的一个重要因素。另外,反应增强现象还可以被钙离子通透的AMPA受体（Ca^2＋-permeable AMPA receptor,CP-AMPAR）的拈抗剂阻断,说明通过钙离子通透的谷氨酸受体内流的Ca^2＋与胞内Ca^2＋浓度的改变有关。进一步发现,胞外灌流ryanodine或caffeine也可以消除反应增强现象,说明由钙诱导的钙释放（calcium—induced calcium release,CICR）引起的钙信号可能也参与了反应增强现象的产生。结果提示,CICR和CP—AMPAR与重复性红光刺激引起的LHC对红光的反应增强有关。     

Complex evaluation of human monocyte‐derived dendritic cells for cancer immunotherapy

Dendritic cell (DC) immunotherapy is capable of generating tumour‐specific immune responses. Different maturation strategies were previously tested to obtain DC capable of anti‐cancer responses in vitro, usually with limited clinical benefit. Mutual comparison of currently used maturation strategies and subsequent complex evaluation of DC functions and their stimulatory capacity on T cells was performed in this study to optimize the DC vaccination strategy for further clinical application. DC were generated from monocytes using granulocyte–macrophage colony‐stimulating factor (GM‐CSF) and interleukin (IL)‐4, pulsed with whole tumour cell lysate and then matured with one of five selected maturation strategies or cultured without additional maturation stimulus. DC were characterized with regard to their surface marker expression, cytokine profiles, migratory capacity, allogeneic and autologous T cell stimulatory capacity as well as their specific cytotoxicity against tumour antigens. We were able to demonstrate extensive variability among different maturation strategies currently used in DC immunotherapeutic protocols that may at least partially explain limited clinical benefit of some clinical trials with such DC. We identified DC matured with interferon‐γ and lipopolysaccharide as the most attractive candidate for future clinical trials in cancer immunotherapy.     

Migration from plant to plant: an important factor controlling densities of the epiphytic cladoceran <Emphasis Type="Italic">Alona</Emphasis> (Chydoridae,Anomopoda) on lake vegetation

We investigated seasonal changes in the density of epiphytic cladocerans Alona spp. (Chydoridae, Anomopoda) in two habitats, emergent and submerged aquatic plants, in Lake Suwa, Japan, from April to August 1998 and from April to November 2000. Alona had a density peak in early June on reeds (emergent) and in late June on Potamogeton malaianus (submerged). In summer, Alona density remained low in both habitats. Although density was positively correlated with the abundance of epiphytic algae, the birth rate was constant and no correlation between algal abundance and clutch size was detected. In a field experiment using ropes as an artificial substrate covered with high and low densities of epiphytic algae as food, more Alona attached to the ropes with the high density of algae. These results suggest that Alona may select food-rich habitats and migrate seasonally, and that migration is an important factor in the population dynamics of epiphytic chydorid cladocerans such as Alona. In Lake Suwa, Alona may migrate from the reed zone to the submerged macrophyte zone in June.     

Habitat use and early winter movements by juvenile Atlantic cod in a coastal area of Newfoundland

Acoustic telemetry was used to monitor the movements and landscape scale habitat use of age 2–3 year juvenile Atlantic cod Gadus morhua in Newman Sound, a coastal fjord of Newfoundland, during late autumn and early winter (24 October 1999 to 22 January 2000). Substratum, bathymetric relief and depth use were studied to determine if it differed from the pattern expected given an absence of selectivity (habitat use proportional to habitat availability). Prior to winter migrations, most Atlantic cod maintained small home ranges (0·5–33·4 ha, median = 2·1 ha) although a few individuals moved more widely. No relationship between total length (L_T) and home range size was detected. In Inner Newman Sound, Atlantic cod occupied depths of 10–29 m more than expected given availability, while depths of 0–9 and 40–59 m were underutilized. No significant relationship between depth and L_T was detected. Areas of medium (5–10%) or high (>10%) bathymetric relief and boulder or kelp habitats were used significantly more than expected given the availability of these habitats. Sand and eelgrass substrata were underutilized given availability, although many Atlantic cod used sandy‐bottomed areas to some degree. Flexibility in habitat use by the individuals that were studied suggested reduced predation risk relative to younger conspecifics. Winter migrations to deeper water beyond Newman Sound began in mid‐November, coinciding with the disappearance of the thermocline, and continued until 27 December. Approximately 30% of monitored individuals did not migrate and maintained their home ranges into the winter season. No significant differences in L_T between migrating and resident groups were detected, however, the condition of migrating fish was significantly higher than in resident fish. This finding supports the theory that feeding history plays a role in the decision to undertake migration.     

Use of wetlands at the mouth of the Yangtze River by shorebirds during spring and fall migration

ABSTRACT.   The mouth of the Yangtze River is an important stopover site for migratory shorebirds using the East Asian-Australasian Flyway. From 1984 to 2004, we censused and banded shorebirds and monitored hunting activities at the mouth of the Yangtze River to understand how shorebirds used the study area. Counts and banding data revealed greater numbers of shorebirds at the mouth of the Yangtze River during northward migration (spring) than during southward migration (fall), with ratios varying from 1.5:1 to 7.2:1 at different sites from 1984 to 2005. The most common species observed during spring (northward) migration were Great Knots ( Calidris tenuirostris ), Red Knots ( Calidris canutus ), Bar-tailed Godwits ( Limosa lapponica ), Sharp-tailed Sandpipers ( Calidris acuminata ), and Red-necked Stints ( Calidris ruficollis ). During spring 2003–2004, 96.98% of the shorebirds observed were adults (ASY or older) and 3% were after hatching-year and second-year birds (AHY or SY). In contrast, almost all (94.73%) birds counted during the fall were hatching-year (HY) birds. These results indicate that adult shorebirds either use a different migration route during fall migration or use the same route, but do not stop at the mouth of the Yangtze River. HY birds, however, may depend on the coastal stopover sites for feeding during their first southward passage.     

MORPHOLOGICAL AND MOLECULAR VARIATION ACROSS A MIGRATORY DIVIDE IN WILLOW WARBLERS,PHYLLOSCOPUS TROCHILUS

A migratory divide is a narrow region in which two populations showing different migratory directions meet arid presumably also mate and hybridize. Banding of willow warblers, Phylloscopus trochilus, in Europe has demonstrated a migratory divide latitudinally across central Scandinavia. In autumn, southern birds migrate southwest to tropical West Africa, whereas northern birds migrate southeast to East and South Africa. The migratory divide is associated with concordant differences in size and plumage coloration. Based on morphology, we estimate the width of the transition zone between northern and southern willow warblers to be less than 350 km. We found indication of linkage disequilibria around the migratory divide, in that measures of body size were correlated with plumage coloration within the contact zone, but uncorrelated within the populations south or north of the contact zone. The presence of linkage disequilibria and the fact that several morphological clines occur together suggest that the hybrid zone is a result of secondary contact between populations that have differentiated in allopatry. This interpretation is in accord with the knowledge of the recolonization pattern of the Scandinavian peninsula after the last glaciation; animals and plants appeared to have colonized either from the south or from the north around the northern bay of the Baltic Sea. If northern and southern willow warblers resided in allopatric populations during late Pleistocene glaciations and the hybrid zone is a result of postglacial range expansions, we would expect some degree of genetic differentiation accumulated during the period in isolation. In contrast, northern and southern willow warblers are near panmictic in the frequencies of alleles of mitochondrial DNA and at two microsatellite loci. The observed pattern, clear morphological and behavioral differentiation without genetic differentiation at neutral loci, suggests either that the differences are maintained by strong selection on the expressed genes in combination with high levels of current gene flow or, in the case of weak gene flow, that the divergence in morphology and behavior is very recent.     

Enhancement of endothelial cell migration and in vitro tube formation by TAP20, a novel beta 5 integrin-modulating, PKC theta-dependent protein

Migration, proliferation, and tube formation of endothelial cells are regulated by a protein kinase C isoenzyme PKCtheta. A full-length cDNA encoding a novel 20-kD protein, whose expression was PKCtheta-dependent, was identified in endothelial cells, cloned, characterized, and designated as theta-associated protein (TAP) 20. Overexpression of TAP20 decreased cell adhesion and enhanced migration on vitronectin and tube formation in three-dimensional culture. An antiintegrin alphavbeta5 antibody prevented these TAP20 effects. Overexpression of TAP20 also decreased focal adhesion formation in alphavbeta3-deficient cells. The interaction between TAP20 and beta5 integrin cytoplasmic domain was demonstrated by protein coprecipitation and immunoblotting. Thus, the discovery of TAP20, which interacts with integrin beta5 and modulates cell adhesion, migration, and tube formation, further defines a possible pathway to angiogenesis dependent on PKCtheta.