Taura syndrome virus from Belize represents a unique variant.
(9/55)
A Taura syndrome virus (TSV) isolate from cultured Penaeus vannamei grown in Belize, Central America was characterized and shown to be a unique isolate. Mortality rates in laboratory infections of specific pathogen-free (SPF) P. vannamei, reactivity of the virus with monoclonal antibody (MAb) 1A1 and phylogenetic analysis demonstrated that the Belize isolate (BLZ02TSV) is a new valiant of TSV. The Hawaiian 1994 TSV isolate (HI94TSV, GenBank AF277675) was used as the reference isolate for these studies. Laboratory infections of SPF P. vannamei with BLZ02TSV demonstrated higher mortalities and earlier onset of mortalities compared to infections with HI94TSV. Shrimp tissues infected with BLZ02TSV reacted with a TSV-specific gene probe by in situ hybridization and were positive by RT-PCR using TSV diagnostic primers, thus indicating that the isolate was TSV. However, Western blot analysis and immunohistochemistry using MAb 1A1 demonstrated that BLZ02TSV did not react with the antibody, suggestive of changes in the VP1 region of the genome that codes for the polypeptide to which MAb 1A1 binds. Phylogenetic analysis of a 1.3 kbp fragment of the TSV VP1 capsid region revealed that BLZ02TSV represents a distinct group among more than 29 isolates of TSV studied thus far. This research demonstrates that BLZ02TSV is a unique isolate of TSV and reiterates a problem related to the use of MAb 1A1 for detection of TSV in clinical specimens. (+info)
A poor start in life negatively affects dominance status in adulthood independent of body size in green swordtails Xiphophorus helleri.
(10/55)
Whilst there is an abundance of studies revealing how dominance interactions affect access to resources critical for survival and reproductive success, very little is known about how dominance status is influenced by early life experiences. However, there is increasing evidence that early developmental trajectories can shape the physiology and behaviour of the adult. In particular, compensatory growth following a period of poor nutrition can have long-term effects on the phenotype. Since catch-up growth increases daily energy requirements and hence the motivation to acquire sufficient resources, it might either increase or decrease competitive ability and aggression. Here we test whether growth compensation early in life subsequently affects the dominance status of adult male swordtail fishes Xiphophorus helleri, a species with strong sexual dimorphism and male-male competition. Males that experienced a period of restricted food early in life subsequently caught up and achieved the same adult body and ornament size as control males that had been raised on ad libitum food throughout development, but were subordinate to size-matched controls, suggesting a trade-off between sexual attractiveness and competitive ability. This indicates that early life history and/or growth trajectory can be an important determinant of competitive ability independent of current body size. (+info)
A randomized, controlled field trial for the prevention of jellyfish stings with a topical sting inhibitor.
(11/55)
BACKGROUND: Jellyfish stings are a common occurrence among ocean goers worldwide with an estimated 150 million envenomations annually. Fatalities and hospitalizations occur annually, particularly in the Indo-Pacific regions. A new topical jellyfish sting inhibitor based on the mucous coating of the clown fish prevents 85% of jellyfish stings in laboratory settings. The field effectiveness is unknown. The objective is to evaluate the field efficacy of the jellyfish sting inhibitor, Safe Sea. METHODS: A double-blind, randomized, placebo-controlled trial occurred at the Dry Tortugas National Park, FL, USA and Sapodilla Cayes, Belize. Participants were healthy volunteers planning to snorkel for 30 to 45 minutes. Ten minutes prior to swimming, each participant was directly observed applying a blinded sample of Safe Sea (Nidaria Technology Ltd, Jordan Valley, Israel) to one side of their body and a blinded sample of Coppertone (Schering-Plough, Kenilworth, NJ, USA) to the contralateral side as placebo control. Masked 26 g samples of both Safe Sea SPF15 and Coppertone SPF15 were provided in identical containers to achieve 2 mg/cm(2) coverage. Sides were randomly chosen by participants. The incidence of jellyfish stings was the main outcome measure. This was assessed by participant interview and examination as subjects exited the water. RESULTS: A total of 82 observed water exposures occurred. Thirteen jellyfish stings occurred during the study period for a 16% incidence. Eleven jellyfish stings occurred with placebo, two with the sting inhibitor, resulting in a relative risk reduction of 82% (95% confidence interval: 21%-96%; p= 0.02). No seabather's eruption or side effects occurred. CONCLUSIONS: Safe Sea is a topical barrier cream effective at preventing >80% jellyfish stings under real-world conditions. (+info)
Sponge systematics by starfish: predators distinguish cryptic sympatric species of Caribbean fire sponges, Tedania ignis and Tedania klausi n. sp. (Demospongiae, Poecilosclerida).
(12/55)
Tedania ignis (Duchassaing and Michelotti, 1864), the fire sponge, is common throughout the tropical western Atlantic, and is a popular species for studies of ecology, larval biology, and chemistry. T. ignis is readily consumed by seagrass-dwelling starfish, and so finding sponges similar to this species in a seagrass meadow provoked closer scrutiny. A variety of ecological, morphological, and molecular traits consistently and unambiguously distinguish T. ignis from a cryptic sympatric congener, here described as Tedania klausi, n. sp. Starfish that consume T. ignis reject T. klausi, and angelfish consume T. klausi less quickly. In Belize, T. ignis individuals transplanted to a seagrass meadow inhabited by T. klausi were consumed by starfish, and individuals of T. klausi transplanted to a mangrove-lined creek in which T. ignis flourishes, died. In Panama, many individuals of T. klausi were diseased in May 2004, while adjacent individuals of T. ignis were unaffected. Spicule types are the same in the two forms, and sizes overlap; but within individuals, the relative sizes of styles and tylotes differ in a pattern that distinguishes the two forms. Comparison of DNA sequences for mitochondrial cytochrome c oxidase subunit I (COI) revealed that 8 single nucleotide mutations consistently differ between the two forms regardless of habitat (seagrass vs. mangrove) and geographically separated sites (Belize vs. Panama). (+info)
Caribbean placozoan phylogeography.
(13/55)
We here address placozoan distribution and phylogeography in five locations in the Caribbean Sea. We performed a coarse-resolution presence/absence survey of placozoans in Belize, Bermuda, Grenada, Jamaica, and Panama and a fine-resolution study of the distribution of placozoans in Twin Cays, Belize. Placozoans were recovered in every country sampled. Animals were sequenced at the mitochondrial 16S rDNA locus, and our analysis identified four of the five previously identified clades present in the Caribbean. In addition, we discovered two new haplotypes within one of these clades, and we found sympatric clades in Belize, Bermuda, Jamaica, and Panama. These studies provide further molecular evidence for species diversity within the Phylum Placozoa. (+info)
Leishmania mexicana infection of the eyelid in a traveler to Belize.
(14/55)
A 50 year-old man, a United States resident, presented in Texas with a violaceous non-ulcerating lesion, involving the entire lower eyelid. The patient had traveled to a jungle area of Belize several hours drive from the capital city. Leishmania mexicana was isolated. The lesion only partially resolved after an initial course of sodium stibogluconate, requiring retreatment. At two years of follow-up, there was no relapse. The parasite isolated from the patient caused a progressive, non-ulcerating lesion in an experimental mouse footpad infection. This is an unusual case of cutaneous leishmaniasis in a traveler. Travelers must be educated about personal protective measures to prevent exotic infections acquired during travel. (+info)
Pathoecology and paleodiet in postclassic: historic Maya from northern coastal Belize.
(15/55)
This paper examines the synergism among diet, disease, and ecology at two related coastal Maya sites in Belize (Marco Gonzalez and San Pedro) for the Postclassic and Historic periods (1350-1650 AD), which immediately follow the Classic period collapse. Stable carbon- and nitrogen-isotope ratios in collagen and stable carbon-isotope ratios in structural carbonate were analysed for bones from 65 humans and a wide variety of faunal species. There are no apparent differences in whole diets or degree of carnivory between individuals with lesions indicative of anemia and those without, but those with lesions appear to have consumed significantly more C4 foods and protein from lower trophic levels. Non-specific infection (periostitis) and vitamin C deficiency (scurvy) are also present in high frequencies and appear to co-occur with lesions indicative of anemia, particularly in childhood. Individuals with scurvy also appear to have consumed significantly more C4 foods than normal individuals. Spondyloarthropathy is common in adults. These findings are discussed in light of: (1) the debate on how anemia versus scurvy are manifest and diagnosed, (2) Spanish ethnohistoric descriptions of the poor state of Maya health at the time of contact, and (3) the Osteological Paradox. We suggest that although this coastal environment exacerbated morbidity because of possible parasitic infection, the inhabitants were probably able to survive physiological stresses better than either their inland contemporaries or their modern counterparts. (+info)
Rapid concerted evolution in animal mitochondrial DNA.
(16/55)
Recombinational genetic processes are thought to be rare in the uniparentally inherited mitochondrial (mt) DNA molecules of vertebrates and other animals. Here, however, we document extremely rapid concerted microevolution, probably mediated by frequent gene conversion events, of duplicated sequences in the mtDNA control region of mangrove killifishes (Kryptolebias marmoratus). In local populations, genetic distances between paralogous loci within an individual were typically smaller (and often zero) than those between orthologous loci in different specimens. These findings call for the recognition of concerted evolution as a microevolutionary process and gene conversion as a likely recombinational force in animal mtDNA. The previously unsuspected power of these molecular phenomena could greatly impact mtDNA dynamics within germ cell lineages and in local animal populations. (+info)