Identification of Vibrio spp. in vibriosis Penaeus vannamei using developed monoclonal antibodies

Immunohistochemical study using monoclonal antibodies specific to various shrimp viruses and Vibrio spp. was performed in shrimp samples died from unknown cause with symptoms of black stripes on lateral sides of cephalothorax or smoky body coloration. The positive results in muscular tissue were obtained with MAb VAL57 (specific to Vibrio spp.) and in hepatopancreas tissues with MAbs VVB158 (specific to V. vulnificus) and VPC701 (specific to V. parahaemolyticus). Twelve isolates of Vibrio spp. isolated from shrimp tissues were identified with various MAbs by dot blotting, biochemical tests and 16S rRNA gene. The results revealed three groups of V. vulnificus and one group of V. shilonii. All four groups of isolated Vibrio spp. were immunologically and biochemically different. None of the V. parahaemolyticus-like bacterium was isolated. The results demonstrated that the mortality in shrimp is accompanied by the presence of Vibrio spp.     

Light- and seasonal-induced plasticity in leaf morphology, N partitioning and photosynthetic capacity of two temperate deciduous species

Processes involved in leaf photosynthetic acclimation to light and throughout the growing season were investigated in two hardwood species (Acer saccharum and Betula alleghaniensis), which differed in their level of shade-tolerance. For both species, variation in traits related to (i) leaf morphology (LMA, leaf mass:area ratio), (ii) leaf N content (N_A, leaf nitrogen content on an area basis and N_M, N concentration in leaf dry mass), (iii) leaf N partitioning among photosynthetic functions (P_r, N allocated to Rubisco, and P_b, N allocated to bioenergetics), and (iv) leaf photosynthetic capacity (V_cmax, maximal carboxylation rates, and J_max, maximal light-driven electron flow) were assessed at three different times during the growing season (early, mid- and late summer) and under four contrasting light regimes (40, 17, 6 and 2% of full sunlight). For both species, light-driven variation in most traits was greater than their seasonally driven variation. Furthermore, results showed for both species the pre-eminence of LMA changes in the light-driven acclimation of N_A. Importance of N_M to variation in N_A was restricted to seasonal acclimation, especially for the less shade-tolerant species, B. alleghaniensis. Similarly, for both species, light-driven acclimation of leaf photosynthetic capacities was tightly related to variation in N_A, which was related to LMA changes. However, variation in P_r and P_b better explained seasonally driven variation in V_cmax and J_max, specifically under lower light levels, where N_A was low. Thus, the great variability observed for leaf activity in response to contrasting light environments was related to efficient morphological adjustments, regardless of species level of shade-tolerance. Finally, physiological adjustments were mainly involved in fine-scale changes observed during seasonally driven acclimation of leaves, when LMA was constrained to a slight range of variation.     

Development of multiplex PCR assay for rapid detection of Riemerella anatipestifer, Escherichia coli, and Salmonella enterica simultaneously from ducks

Three pathogens, Riemerella anatipestifer, Escherichia coli, and Salmonella enterica, are leading causes of bacterial fibrinous pericarditis and perihepatitis in ducks in China and worldwide. It is difficult to differentiate these pathogens when obtaining a diagnosis on clinical signs and pathological changes. The aim of this research was to develop a multiplex polymerase chain reaction (m-PCR) that could discriminate R. anatipestifer, E. coli, and S. enterica rapidly in field isolates, or detect the three bacteria in clinical samples from diseased ducks. We selected the DnaB helicase (dnaB) gene of R. anatipestifer, alkaline phosphatase (phoA) gene of E. coli and invasion protein (invA) gene of S. enterica as target genes. In optimized conditions, the limitation of detection was approximately 10³ colony forming units (CFU) of each of these three bacterial pathogens per PCR reaction tube. The m-PCR method showed specific amplification of respective genes from R. anatipestifer, E. coli, and S. enterica. Using the m-PCR system, bacterial strains isolated from diseased ducks in our laboratory were categorized successfully, and the pathogens could also be detected in clinical samples from diseased ducks. Therefore, the m-PCR system could distinguish the three pathogens simultaneously, for identification, routine molecular diagnosis and epidemiology, in a single reaction.     

Immune responses induced by Pelargonium sidoides extract in serum and nasal mucosa of athletes after exhaustive exercise: Modulation of secretory IgA, IL-6 and IL-15

The evidence that exhaustive exercise may compromise the immune response is mainly confirmed by upper respiratory tract infections which are probably related to the decrease in secretory immunoglobulin A in the upper airway mucosa and/or profile changes of systemic cytokines as well as local cytokines of the upper respiratory tract. An extract from Pelargonium sidoides roots is currently used to treat infections in the upper airways. The aim of the present study was to evaluate the action of this herbal medicine on the immune response of athletes submitted to an intense running session by analyzing the production of immunoglobulin A in their saliva and of cytokines both locally and systemically, using a placebo as control. The results show that Pelargonium sidoides extract modulates the production of secretory immunoglobulin A in saliva, both interleukin-15 and interleukin-6 in serum, and interleukin-15 in the nasal mucosa. Secretory immunoglobulin A levels were increased, while levels of IL-15 and IL-6 were decreased. Based on this evidence, we suggest that this herbal medicine can exert a strong modulating influence on the immune response associated with the upper airway mucosa in athletes submitted to intense physical activity.     

Semicircular canal system in early primates

Mammals with more rapid and agile locomotion have larger semicircular canals relative to body mass than species that move more slowly. Measurements of semicircular canals in extant mammals with known locomotor behaviours can provide a basis for testing hypotheses about locomotion in fossil primates that is independent of postcranial remains, and a means of reconstructing locomotor behaviour in species known only from cranial material. Semicircular canal radii were measured using ultra high resolution X-ray CT data for 9 stem primates (“plesiadapiforms”; n = 11), 7 adapoids (n = 12), 4 omomyoids (n = 5), and the possible omomyoid Rooneyia viejaensis (n = 1). These were compared with a modern sample (210 species including 91 primates) with known locomotor behaviours. The predicted locomotor agilities for extinct primates generally follow expectations based on known postcrania for those taxa. “Plesiadapiforms” and adapids have relatively small semicircular canals, suggesting they practiced less agile locomotion than other fossil primates in the sample, which is consistent with reconstructions of them as less specialized for leaping. The derived notharctid adapoids (excluding Cantius) and all omomyoids sampled have relatively larger semicircular canals, suggesting that they were more agile, with Microchoerus in particular being reconstructed as having had very jerky locomotion with relatively high magnitude accelerations of the head. Rooneyia viejaensis is reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility.     

Inter- and intra-specific differences in euryhalinity determine the spatial distribution of mysids in a temperate European estuary

Mysids are an important component of estuarine hyperbenthos and a major prey item in the food web of many estuaries. Understanding the abiotic and biotic mechanisms determining mysid distributions is therefore important to comprehend the general processes structuring estuarine communities. We carried out field surveys and exposure-survival experiments for three species of mysids, Neomysis integer Leach Mesopodopsis slabberi van Beneden and Rhopalophthalmus tartessicus Vilas-Fernandez, Drake and Sorbe, to link salinity tolerances of different sex and life stages (adults and juveniles) to their spatial distributions within the Guadalquivir estuary, SW Spain. Despite being euryhaline, the three species of mysids were unevenly distributed along the saline gradient, with salinity being the environmental variable which best explained structure changes in the estuarine mysid assemblage. R. tartessicus remained confined to the outer and more marine part of the estuary and showed a higher temporal variation in its salinity-related distribution (position within the salinity gradient). M. slabberi and N. integer displayed wider estuarine distributions but remained associated with intermediate and low salinities, respectively. We found considerable inter- and intra-specific differences in tolerance to sudden salinity changes: N. integer, and juveniles of M. slabberi and R. tartessicus, showed a high tolerance to sudden salinity changes, whereas adults of M. slabberi and R. tartessicus were only tolerant to salinities close to their isosmotic points. For the less euryhaline species M. slabberi and R. tartessicus acclimation to unfavourable salinities decreased survival after exposure to sudden salinity changes. Both location and strength of the salinity gradient were important factors in determining spatial distribution, either directly to avoid osmotic stress and mortality risk (R. tartessicus and M. slabberi) or indirectly to reduce inter-specific mysid competition (N. integer). We suggest inter- and intra-specific euryhalinity differences determine the spatial distribution of mysids and the specific strategies they use to maintain this spatial structure in a highly variable environment.     

Phylogenetic relationships among Southeast Asian climbing bamboos (Poaceae: Bambusoideae) and the Bambusa complex

A phylogenetic analysis of Bambusa and allies based on the plastid DNA non-coding regions rps16-trnQ, trnC-rpoB, trnH-psbA and trnD-T, and a partial nuclear GBSSI gene, was carried out. This included representatives from all four Bambusa subgenera (including type species), a group of segregate Southeast Asian genera distinctive by their climbing–scrambling culms (Dinochloa, Holttumochloa, Kinabaluchloa, Maclurochloa, Soejatmia, Sphaerobambos), and two other Bambusinae genera (Dendrocalamus, Gigantochloa). The results do not support the present subgeneric classification of Bambusa. The climbing Southeast Asian genera, all of which include species previously placed in Bambusa, are distinct from the “core Bambusa group” (type species and alliance) and the Bambusa complex generally.     

Septal pore complex morphology in the Agaricomycotina (Basidiomycota) with emphasis on the Cantharellales and Hymenochaetales

The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales.It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type.     

Attraction of four entomopathogenic nematodes to four white grub species

To better understand the differences in the efficacy of entomopathogenic nematode species against white grub species, we are studying the various steps of the infection process of entomopathogenic nematodes into different white grub species using nematode species/strains with particular promise as white grub control agents. In this study we compared the attraction of the entomopathogenic nematodes Steinernema scarabaei (AMK001 strain), Steinernema glaseri (NC1 strain), Heterorhabditis zealandica (X1 strain), and Heterorhabditis bacteriophora (GPS11 strain) to third-instars of the scarabs Popillia japonica, Anomala orientalis, Cyclocephala borealis, and Rhizotrogus majalis, and late-instar greater wax moth, Galleria mellonella, larvae. Individual larvae were confined at the bottom of 5.5 cm vertical sand columns, nematodes added to the sand surface after 24 h, and nematodes extracted after another 24 h. Nematode attraction to hosts was strongly affected by nematode species but the effect of insect species varied with nematode species. S. glaseri had a high innate dispersal rate (i.e., in absence of insects) and was strongly attracted to insects without significant differences among insect species. S. scarabaei had a very low innate dispersal rate so that even a strong relative response to insects resulted in low absolute dispersal rates toward insects. S. scarabaei tended to be most attracted to G. mellonella and least attracted to C. borealis. H. zealandica had a high innate dispersal rate but only responded weakly to insects without significant differences among species. H. bacteriophora had limited innate dispersal and only weakly responded to insects with G. mellonella tending to be the most attractive and C. borealis the least attractive insect. It has to be noted that we cannot exclude that the use of different rearing hosts (A. orientalis and P. japonica larvae for S. scarabaei, G. mellonella larvae for the other nematodes) might have had an impact on the nematodes dispersal and relative attraction behavior. This study indicates that host attractiveness and nematode dispersal rates may contribute but do not play a major role in the variability in white grub susceptibility and/or nematode virulence.     

Altered expression of Autism-associated genes in the brain of Fragile X mouse model

Autism is a severe neurodevelopmental disorder, which typically emerges in early childhood. Most cases of autism have not been linked to mutations in a specific gene, and the etioloty of the disorder remains to be established [S.S. Moy, J.J. Nadler, T.R. Magnuson, J.N. Crawley, Mouse models of autism spectrum disorders: the challenge for behavioral genetics, Am. J. Med. Genet. 142 (2006) 40-51]. Fragile X syndrome is caused by mutation in the FMR1 gene and is characterized by mental retardation, physical abnormalities, and, in most case, autistic-like behavior [R.J. Hagerman, A.W. Jackson, A. Levitas, B. Rimland, M. Braden, An analysis of autism in fifty males with the Fragile X syndrome, Am. J. Med. Genet. 23 (1986) 359-374, C.E. Bakker, C. Verheij, R. Willemsen, R. van der Helm, F. Oerlemans, M. Vermeij, A. Bygrave, A.T. Hoogeveen, B.A. Oostra, E. Reyniers, K. De Boulle, R. D’Hooge, P. Cras, D. van Velzen, G. Nagels, J.J. Marti, P. De Deyn, J.K. Darby, P.J. Willems, Fmr1 knockout mice: a model to study Fragile X mental retardation, Cell 78 (1994) 23-33]. The FMR1 knockout (KO) mouse is one of the best characterized animal models for human disorders associated with autism [S.S. Moy, J.J. Nadler, T.R. Magnuson, J.N. Crawley, Mouse models of autism spectrum disorders: the challenge for behavioral genetics, Am. J. Med. Genet. 142 (2006) 40-51]. We have used real-time PCR to investigate changes in expression levels of three genes: WNT2, MECP2, and FMR1 in different brain regions of Fagile X mice and litter mate controls. We found major changes in the expression pattern for the three genes examined. FMR1, MECP2, and WNT2 expression were drastically down regulated in the Fragile X mouse brain.     

Evolutionary history of frogfishes (Teleostei: Lophiiformes: Antennariidae): a molecular approach

Fishes of the family Antennariidae (order Lophiiformes) are primarily shallow-water benthic forms found in nearly all tropical and subtropical oceans and seas of the world, with some taxa extending into temperate waters. Despite an earlier attempt based on morphology, no previous hypothesis of intergeneric relationships of the Antennariidae exists. To resolve phylogenetic relationships within the Antennariidae, and to test the validity of species groups within Antennarius, DNA sequences from the mitochondrial 16S and cytochrome oxidase c subunit 1 (COI) genes, and nuclear recombination activating gene 2 (RAG2), for 25 described and four undescribed antennariid species, representing 10 of 12 known genera and one undescribed genus, were unambiguously aligned and analyzed using Bayesian and maximum likelihood methods. The markers were partitioned and analyzed for substitution saturation and only the third codon position of COI (COI-3) was found to have reached saturation. However, analysis of both datasets, one with the saturated data and one without, differed only slightly. All molecular analyses recovered two major clades, one comprised of Fowlerichthys, Antennarius, Histrio, and Antennatus; and another containing Rhycherus, Antennariidae gen. et sp. nov., Kuiterichthys, Phyllophryne, Echinophryne, Tathicarpus, Lophiocharon, and Histiophryne. Evidence is presented to illustrate a correlation between phylogeny, geographic distribution, and reproductive life history. The results of these analyses provide the first hypothesis of evolutionary relationships within the Antennariidae.     

Lipodystrophies: Disorders of adipose tissue biology

The adipocytes synthesize and store triglycerides as lipid droplets surrounded by various proteins and phospholipids at its surface. Recently, the molecular basis of some of the genetic syndromes of lipodystrophies has been elucidated and some of these genetic loci have been found to contribute to lipid droplet formation in adipocytes. The two main types of genetic lipodystrophies are congenital generalized lipodystrophy (CGL) and familial partial lipodystrophy (FPL). So far, three CGL loci: 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), Berardinelli–Seip Congenital Lipodystrophy 2 (BSCL2) and caveolin 1 (CAV1) and four FPL loci: lamin A/C (LMNA), peroxisome proliferator-activated receptor γ (PPARG), v-AKT murine thymoma oncogene homolog 2 (AKT2) and zinc metalloprotease (ZMPSTE24), have been identified. AGPAT2 plays a critical role in the synthesis of glycerophospholipids and triglycerides required for lipid droplet formation. Another protein, seipin (encoded by BSCL2 gene), has been found to induce lipid droplet fusion. CAV1 is an integral component of caveolae and might contribute towards lipid droplet formation. PPARγ and AKT2 play important role in adipogenesis and lipid synthesis. In this review, we discuss and speculate about the contribution of various lipodystrophy genes and their products in the lipid droplet formation.     

Osmoregulatory disturbances induced by the parasitic barnacle Loxothylacus texanus (Rhizocephala) in the crab Callinectes rathbunae (Portunidae)

The osmoregulatory response of the blue crab Callinectes rathbunae parasitized with the rhizocephalan barnacle Loxothylacus texanus, and subjected to sudden salinity changes, was experimentally measured in the laboratory. Parasitized and control crabs were exposed to salinity changes every 3 h and their hemolymph osmolality measured. Two experiments, one with increasing salinity conditions (5‰, 12‰, 19‰, 25‰) and a second one with decreasing salinities (35‰, 25‰, 15‰, 5‰) were conducted. The results show that L. texanus significantly alters the hemolymph osmolality of C. rathbunae maintaining it at lower than normal levels. In the increasing salinity trial, the hypoosmotic hemolymph condition of parasitized crabs was present at all salinities tested, whereas in the decreasing salinity trial a significant effect was found only at salinities of 5‰ and 15‰. Since C. rathbunae is constantly subjected to abrupt salinity changes in the tropical estuaries where it occurs, moving into high salinity areas may be the only way to cope with the impact of L. texanus.     

RPB2 sequences reveal a close phylogenetic relationship between tetraploid Hordelymus and diploid Hordeum species in Triticeae (Poaceae)

The origin of Hordelymus genome has been debated for years, and no consensus conclusion was reached. In this study, we sequenced and analyzed the RPB2 (RNA polymerase subunit II) gene from Hordelymus europaeus (L.) Harz, and its potential diploid ancestor species those were suggested in previous studies. The focus of this study was to examine the phylogenetic relationship of Hordelymus genomes with its potential donor Hordeum, Psathyrostachys, and Taeniatherum species. Two distinguishable copies of sequences were obtained from H. europaeus. The obvious difference between the two copies of sequences is a 24 bp indel (insertion/deletion). Phylogenetic analysis showed a strong affinity between Hordeum genome and Hordelymus with 85% bootstrap support. These results suggested that one genome in tetraploid H. europaeus closely related to the genome in Hordeum species. Another genome in H. europaeus is sister to the genomes in Triticeae species examined here, which corresponds well with the recently published EF-G data. No obvious relationship was found between Hordelymus and either Ta genome donor, Taeniatherum caput-medusae or Ns genome donor, Psathyrostachys juncea. Our data does not support the presence of Ta and Ns genome in H. europaeus, and further confirms that H. europaeus is allopolyploid.     

Relationships between Bambusa species (Poaceae,Bambusoideae) revealed by random amplified polymorphic DNA

RAPD (random amplified polymorphic DNA) molecular markers were used to investigate relationships between a sample of Bambusa species from South Eastern China that have been placed in Bambusa or in several segregate genera, Dendrocalamopsis, Leleba, Lingnania, Neosinocalamus and Sinocalamus by different authors. On the resultant neighbor-joining tree, a thorny core Bambusa cluster was distinguished, as was a Lingnania group, and a cluster of Dendrocalamus species with more capitate inflorescences. However, Leleba was found to be a polyphyletic group in the present study.     

Morphology and molecular taxonomy of Evlachovaea-like fungi,and the status of this unusual conidial genus

The entomopathogenic anamorphic genus Evlachovaea was described to differ from other fungi in forming its conidia obliquely to the axis of the conidiogenous cell and with successive conidia having alternate orientations with a zipper- or chevron-like arrangement resulting in flat, ribbon-like chains. Morphological and molecular studies of six Evlachovaea-like isolates baited from Central Brazilian soils using Triatoma infestans (a vector of Chagas disease) and of other entomopathogens with Evlachovaea-like conidiogenesis led to a re-evaluation of the status of this little known fungal genus. The Brazilian isolates formed two distinct groups based on gene sequences for both the internal transcribed spacer (ITS) and translation elongation factor (EF-1α) genes, morphology, and growth patterns; both groups also differed from the type species, Evlachovaea kintrischica. More detailed studies of these fungi indicated that the alternatingly oblique orientations of forming conidia are neither a stable nor invariant character (even on single phialides). Furthermore, the molecular cladistic analysis unambiguously placed the Evlachovaea isolates firmly within the genus Isaria (Hypocreales: Cordycipitaceae). The ITS sequences of E. kintrischica were very similar or even identical to those of Isaria amoenerosea and Isaria cateniobliqua, thereby suggesting that E. kintrischica is a synonym of one of these species, and that the genus Evlachovaea must be treated as a later synonym of Isaria, which must now be recognized to include several highly divergent modes of conidiogenesis. These taxonomic findings are discussed in the context of dramatic changes recently imposed on the nomenclatural standards used to determine the correct names of all pleomorphic fungi.