207 research outputs found
<i>Thalassomonas loyana</i> sp. nov., a causative agent of the white plague-like disease of corals on the Eilat coral reef
The taxonomic position of the coral pathogen strain CBMAI 722T was determined on the basis of molecular and phenotypic data. We clearly show that the novel isolate CBMAI 722T is a member of the family Colwelliaceae, with Thalassomonas ganghwensis as the nearest neighbour (95 % 16S rRNA gene sequence similarity). CBMAI 722T can be differentiated from its nearest neighbour on the basis of phenotypic and chemotaxonomic features, including the utilization of cellobiose and l-arginine, the production of alginase and amylase, but not oxidase, and the presence of the fatty acids 12 : 0 3-OH and 14 : 0, but not 10 : 0 or 15 : 0. The DNA G+C content of CBMAI 722T is 39·3 mol%. We conclude that this strain represents a novel species for which we propose the name Thalassomonas loyana sp. nov., with the type strain CBMAI 722T (=LMG 22536T). This is the first report of the involvement of a member of the family Colwelliaceae in coral white plague-like disease
Microbial taxonomy in the post-genomic era: Rebuilding from scratch?
Microbial taxonomy should provide adequate descriptions of bacterial, archaeal, and eukaryotic microbial diversity in ecological, clinical, and industrial environments. Its cornerstone, the prokaryote species has been re-evaluated twice. It is time to revisit polyphasic taxonomy, its principles, and its practice, including its underlying pragmatic species concept. Ultimately, we will be able to realize an old dream of our predecessor taxonomists and build a genomic-based microbial taxonomy, using standardized and automated curation of high-quality complete genome sequences as the new gold standard.National Science Foundation (U.S.) (NSF Grant DEB-1046413)National Science Foundation (U.S.) (NSF Grant CNS-1305112)National Science Foundation (U.S.) (NSF Grant DEB 0918333)National Science Foundation (U.S.) (NSF grant OCE 1441943)Gordon and Betty Moore FoundationUnited States. Dept. of Energy. Office of ScienceUnited States. Dept. of Energy. Office of Biological and Environmental ResearchOak Ridge National LaboratoryCarlos Chagas Filho Foundation for Research Support of the State of Rio de JaneiroBrazil. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (grant)Conselho Nacional de Pesquisas (Brazil
Prior Mating Experience Modulates the Dispersal of Drosophila in Males More Than in Females
Cues from both an animal’s internal physiological state and its local environment may influence its decision to disperse. However, identifying and quantifying the causative factors underlying the initiation of dispersal is difficult in uncontrolled natural settings. In this study, we automatically monitored the movement of fruit flies and examined the influence of food availability, sex, and reproductive status on their dispersal between laboratory environments. In general, flies with mating experience behave as if they are hungrier than virgin flies, leaving at a greater rate when food is unavailable and staying longer when it is available. Males dispersed at a higher rate and were more active than females when food was unavailable, but tended to stay longer in environments containing food than did females. We found no significant relationship between weight and activity, suggesting the behavioral differences between males and females are caused by an intrinsic factor relating to the sex of a fly and not simply its body size. Finally, we observed a significant difference between the dispersal of the natural isolate used throughout this study and the widely-used laboratory strain, Canton-S, and show that the difference cannot be explained by allelic differences in the foraging gene
Acute hepatic failure and multi-system organ failure secondary to replacement of the liver with metastatic melanoma
BACKGROUND: Metastatic malignant melanoma to the liver resulting in fulminant hepatic failure is a rare occurrence. CASE PRESENTATION: A 46 year old man presented to hospital with massive hepatomegaly, elevated liver enzymes and increased lactate three weeks following resection of a malignant melanoma from his shoulder (Clark level 5). Initially stable, he decompensated 24 to 48 hours subsequent to presentation with respiratory failure requiring mechanical ventilation, distributive shock requiring high dose vasopressor infusion, coagulopathy refractory to plasma infusion, progressive rise in liver enzymes and severe metabolic abnormalities including hyperkalemia, acidosis, hyperphosphatemia, hyperuricemia and hypocalcemia. Refractory to aggressive physiologic support he received palliation. Autopsy revealed >80% liver infiltration by metastatic malignant melanoma. CONCLUSION: We report a case of fulminant hepatic failure secondary to metastatic malignant melanoma infiltration of the liver
Acute phase of aortic dissection: a pilot study on CD40L, MPO, and MMP-1, -2, 9 and TIMP-1 circulating levels in elderly patients
Low Lipoprotein(a) Concentration Is Associated with Cancer and All-Cause Deaths: A Population-Based Cohort Study (The JMS Cohort Study)
Background: Experimental studies support the anti-neoplastic effect of apo(a), but several clinical studies have reported contradictory results. The purpose of this study was to determine whether a low lipoprotein(a) [Lp(a)] concentration is related to mortality from major causes of death, especially cancer. Methods The subjects were 10,413 participants (4,005 men and 6,408 women) from a multi-center population-based cohort study in Japan (The Jichi Medical School cohort study). The average age at registration was 55.0 years, and the median observation period was 4,559 days. As the estimated hazard ratio was high for both the low and very high Lp(a) levels, we defined two Lp(a) groups: a low Lp(a) group [Lp(a)<80 mg/L] and an intermediate-to-high Lp(a) group [Lp(a)≥80]. Participants who died from malignant neoplasms (n = 316), cardiovascular disease (202), or other causes (312) during the observation period were examined. Results: Cumulative incidence plots showed higher cumulative death rates for the low Lp(a) group than for the intermediate-to-high Lp(a) group for all-cause, cancer, and miscellaneous-cause deaths (p<0.001, p = 0.03, and p = 0.03, respectively). Cox proportional hazards analyses with the sex and age of the participants, body mass index, and smoking and drinking histories as covariates showed that a low Lp(a) level was a significant risk for all-cause, cancer, and miscellaneous-cause deaths (p<0.001, p = 0.003, and p = 0.01, respectively). The hazard ratio (95% CI) [1.48, 1.15–1.92] of a low Lp(a) level for cancer deaths was almost the same as that for a male sex (1.46, 1.00–2.13). Conclusions: This is the first report to describe the association between a low Lp(a) level and all-cause or cancer death, supporting the anti-neoplastic effect of Lp(a). Further epidemiological studies are needed to confirm the present results
Comparative genome analysis of cortactin and HSI:the significance of the F-actin binding repeat domain
Background: In human carcinomas, overexpression of cortactin correlates with poor prognosis. Cortactin is an F-actin-binding protein involved in cytoskeletal rearrangements and cell migration by promoting actin-related protein (Arp)2/3 mediated actin polymerization. It shares a high amino acid sequence and structural similarity to hematopoietic lineage cell-specific protein I (HSI) although their functions differ considerable. In this manuscript we describe the genomic organization of these two genes in a variety of species by a combination of cloning and database searches. Based on our analysis, we predict the genesis of the actin-binding repeat domain during evolution.Results: Cortactin homologues exist in sponges, worms, shrimps, insects, urochordates, fishes, amphibians, birds and mammalians, whereas HSI exists in vertebrates only, suggesting that both genes have been derived from an ancestor cortactin gene by duplication. In agreement with this, comparative genome analysis revealed very similar exon-intron structures and sequence homologies, especially over the regions that encode the characteristic highly conserved F-actin-binding repeat domain. Cortactin splice variants affecting this F-actin-binding domain were identified not only in mammalians, but also in amphibians, fishes and birds. In mammalians, cortactin is ubiquitously expressed except in hematopoietic cells, whereas HSI is mainly expressed in hematopoietic cells. In accordance with their distinct tissue specificity, the putative promoter region of cortactin is different from HSI.Conclusions: Comparative analysis of the genomic organization and amino acid sequences of cortactin and HSI provides inside into their origin and evolution. Our analysis shows that both genes originated from a gene duplication event and subsequently HSI lost two repeats, whereas cortactin gained one repeat. Our analysis genetically underscores the significance of the F-actin binding domain in cytoskeletal remodeling, which is of importance for the major role of HSI in apoptosis and for cortactin in cell migration.</p
RNA Editing Genes Associated with Extreme Old Age in Humans and with Lifespan in C. elegans
The strong familiality of living to extreme ages suggests that human longevity is genetically regulated. The majority of genes found thus far to be associated with longevity primarily function in lipoprotein metabolism and insulin/IGF-1 signaling. There are likely many more genetic modifiers of human longevity that remain to be discovered.Here, we first show that 18 single nucleotide polymorphisms (SNPs) in the RNA editing genes ADARB1 and ADARB2 are associated with extreme old age in a U.S. based study of centenarians, the New England Centenarian Study. We describe replications of these findings in three independently conducted centenarian studies with different genetic backgrounds (Italian, Ashkenazi Jewish and Japanese) that collectively support an association of ADARB1 and ADARB2 with longevity. Some SNPs in ADARB2 replicate consistently in the four populations and suggest a strong effect that is independent of the different genetic backgrounds and environments. To evaluate the functional association of these genes with lifespan, we demonstrate that inactivation of their orthologues adr-1 and adr-2 in C. elegans reduces median survival by 50%. We further demonstrate that inactivation of the argonaute gene, rde-1, a critical regulator of RNA interference, completely restores lifespan to normal levels in the context of adr-1 and adr-2 loss of function.Our results suggest that RNA editors may be an important regulator of aging in humans and that, when evaluated in C. elegans, this pathway may interact with the RNA interference machinery to regulate lifespan
Copper tolerance and distribution of epibiotic bacteria associated with giant kelp Macrocystis pyrifera in southern California
Comparative genomics reveals a widespread distribution of an exopolysaccharide biosynthesis gene cluster among Vibrionaceae
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