Concatenated analysis sheds light on early metazoan evolution and fuels a modern "urmetazoon" hypothesis.

For more than a century, the origin of metazoan animals has been debated. One aspect of this debate has been centered on what the hypothetical "urmetazoon" bauplan might have been. The morphologically most simply organized metazoan animal, the placozoan Trichoplax adhaerens, resembles an intriguing model for one of several "urmetazoon" hypotheses: the placula hypothesis. Clear support for a basal position of Placozoa would aid in resolving several key issues of metazoan-specific inventions (including, for example, head-foot axis, symmetry, and coelom) and would determine a root for unraveling their evolution. Unfortunately, the phylogenetic relationships at the base of Metazoa have been controversial because of conflicting phylogenetic scenarios generated while addressing the question. Here, we analyze the sum of morphological evidence, the secondary structure of mitochondrial ribosomal genes, and molecular sequence data from mitochondrial and nuclear genes that amass over 9,400 phylogenetically informative characters from 24 to 73 taxa. Together with mitochondrial DNA genome structure and sequence analyses and Hox-like gene expression patterns, these data (1) provide evidence that Placozoa are basal relative to all other diploblast phyla and (2) spark a modernized "urmetazoon" hypothesis.

Multiple dicer genes in the early-diverging metazoa.

Dicer proteins are highly conserved, are present in organisms ranging from plants to metazoans, and are essential components of the RNA interference pathway. Although the complement of Dicer proteins has been investigated in many "higher" metazoans, there has been no corresponding characterization of Dicer proteins in any early-branching metazoan. We cloned partial cDNAs of genes belonging to the Dicer family from the anthozoan cnidarian Nematostella vectensis and two distantly related haplotypes (species lineages) of the Placozoa (Trichoplax adhaerens 16S haplotype 1 [H1] and Placozoa sp. [H2]). We also identified Dicer genes in the hydrozoan Hydra magnipapillata and the demosponge Amphimedon queenslandica with the use of publicly available sequence databases. Two Dicer genes are present in each cnidarian species, whereas five Dicer genes each are found in the Porifera and Placozoa. Phylogenetic analyses comparing these and other metazoan Dicers suggest an ancient duplication event of a "Proto-Dicer" gene. We show that the Placozoa is the only known metazoan phylum which contains both representatives of this duplication event and that the multiple Dicer genes of the "basal" metazoan phyla represent lineage-specific duplications. There is a striking diversity of Dicer genes in basal metazoans, in stark contrast to the single Dicer gene found in most higher metazoans. This new data has allowed us to formulate new hypotheses regarding the evolution of metazoan Dicer proteins and their possible functions in the early diverging metazoan phyla. We theorize that the multiple placozoan Dicer genes fulfill a specific biological requirement, such as an immune defense strategy against viruses.

Axial patterning and diversification in the cnidaria predate the Hox system.

Across the animal kingdom, Hox genes are organized in clusters whose genomic organization reflects their central roles in patterning along the anterior/posterior (A/P) axis . While a cluster of Hox genes was present in the bilaterian common ancestor, the origins of this system remain unclear (cf. ). With new data for two representatives of the closest extant phylum to the Bilateria, the sea anemone Nematostella and the hydromedusa Eleutheria, we argue here that the Cnidaria predate the evolution of the Hox system. Although Hox-like genes are present in a range of cnidarians, many of these are paralogs and in neither Nematostella nor Eleutheria is an equivalent of the Hox cluster present. With the exception of independently duplicated genes, the cnidarian genes are unlinked and in several cases are flanked by non-Hox genes. Furthermore, the cnidarian genes are expressed in patterns that are inconsistent with the Hox paradigm. We conclude that the Cnidaria/Bilateria split occurred before a definitive Hox system developed. The spectacular variety in morphological and developmental characteristics shown by extant cnidarians demonstrates that there is no obligate link between the Hox system and morphological diversity in the animal kingdom and that a canonical Hox system is not mandatory for axial patterning.

Transcranial ultrasound from diagnosis to early stroke treatment. 1. Feasibility of prehospital cerebrovascular assessment.

BACKGROUND: To test whether portable duplex ultrasound devices can be used in a prehospital '911' emergency situation to assess intracranial arteries. METHODS: Non-contrast-enhanced transcranial duplex ultrasound studies were performed either immediately at the site of the emergency (i.e. private home) or after transfer into the emergency helicopter/ambulance vehicle. RESULTS: A total of 25 patients were enrolled. In 5/25 cases, intracranial vessels could not be visualized due to insufficient quality of the temporal bone window. In 20/25 cases, bilateral visualization and Doppler flow measurements of the middle cerebral artery could be assessed in a mean time less than 2 min. CONCLUSION: Emergency assessment of intracranial arteries using portable duplex ultrasound devices is feasible shortly after arrival at the patient's site.

Inventory of a Neurological Intensive Care Unit: Who Is Treated and How Long?

Purpose. To characterize indications, treatment, and length of stay in a stand-alone neurological intensive care unit with focus on comparison between ventilated and nonventilated patient. Methods. We performed a single-center retrospective cohort study of all treated patients in our neurological intensive care unit between October 2006 and December 2008. Results. Overall, 512 patients were treated in the surveyed period, of which 493 could be included in the analysis. Of these, 40.8% had invasive mechanical ventilation and 59.2% had not. Indications in both groups were predominantly cerebrovascular diseases. Length of stay was 16.5 days in mean for ventilated and 3.6 days for nonventilated patient. Conclusion. Most patients, ventilated or not, suffer from vascular diseases with further impairment of other organ systems or systemic complications. Data reflects close relationship and overlap of treatment on nICU with a standardized stroke unit treatment and suggests, regarding increasing therapeutic options, the high impact of acute high-level treatment to reduce consequential complications.

Isolation of Hox cluster genes from insects reveals an accelerated sequence evolution rate.

Among gene families it is the Hox genes and among metazoan animals it is the insects (Hexapoda) that have attracted particular attention for studying the evolution of development. Surprisingly though, no Hox genes have been isolated from 26 out of 35 insect orders yet, and the existing sequences derive mainly from only two orders (61% from Hymenoptera and 22% from Diptera). We have designed insect specific primers and isolated 37 new partial homeobox sequences of Hox cluster genes (lab, pb, Hox3, ftz, Antp, Scr, abd-a, Abd-B, Dfd, and Ubx) from six insect orders, which are crucial to insect phylogenetics. These new gene sequences provide a first step towards comparative Hox gene studies in insects. Furthermore, comparative distance analyses of homeobox sequences reveal a correlation between gene divergence rate and species radiation success with insects showing the highest rate of homeobox sequence evolution.

[Discharge letters addressed to caregivers of psychiatric patients: support and psychoeducation]. / Entlassungsbriefe an Angehörige von psychisch Kranken: Vermittlung von Unterstüutzungsangeboten und Psychoedukation.

BACKGROUND: In clinical practise, discharge letters addressed to caregivers are rare. METHOD: We report on a discharge letter, addressed to the family of a 46-year-old patient suffering from a disorganized type of schizophrenia with continuous course. RESULTS: The case report indicates that letters to caregivers are useful to provide psychoeducation, to disburden caregivers and to enhance treatment continuation, prevention of relapse and rehabilitation of the patient. Furthermore, discharge letters to caregivers appreciate the role of relatives as important partners in patients' successful treatment. CONCLUSIONS: Letters to caregivers are an efficient chance to increase confidence and satisfaction of caregivers of psychiatric patients.

Changing hydrozoan bauplans by silencing Hox-like genes.

Regulatory genes of the Antp class have been a major factor for the invention and radiation of animal bauplans. One of the most diverse animal phyla are the Cnidaria, which are close to the root of metazoan life and which often appear in two distinct generations and a remarkable variety of body forms. Hox-like genes have been known to be involved in axial patterning in the Cnidaria and have been suspected to play roles in the genetic control of many of the observed bauplan changes. Unfortunately RNAi mediated gene silencing studies have not been satisfactory for marine invertebrate organisms thus far. No direct evidence supporting Hox-like gene induced bauplan changes in cnidarians have been documented as of yet. Herein, we report a protocol for RNAi transfection of marine invertebrates and demonstrate that knock downs of Hox-like genes in Cnidaria create substantial bauplan alterations, including the formation of multiple oral poles ("heads") by Cnox-2 and Cnox-3 inhibition, deformation of the main body axis by Cnox-5 inhibition and duplication of tentacles by Cnox-1 inhibition. All phenotypes observed in the course of the RNAi studies were identical to those obtained by morpholino antisense oligo experiments and are reminiscent of macroevolutionary bauplan changes. The reported protocol will allow routine RNAi studies in marine invertebrates to be established.

Mitochondrial genome of Trichoplax adhaerens supports placozoa as the basal lower metazoan phylum.

Mitochondrial genomes of multicellular animals are typically 15- to 24-kb circular molecules that encode a nearly identical set of 12-14 proteins for oxidative phosphorylation and 24-25 structural RNAs (16S rRNA, 12S rRNA, and tRNAs). These genomes lack significant intragenic spacers and are generally without introns. Here, we report the complete mitochondrial genome sequence of the placozoan Trichoplax adhaerens, a metazoan with the simplest known body plan of any animal, possessing no organs, no basal membrane, and only four different somatic cell types. Our analysis shows that the Trichoplax mitochondrion contains the largest known metazoan mtDNA genome at 43,079 bp, more than twice the size of the typical metazoan mtDNA. The mitochondrion's size is due to numerous intragenic spacers, several introns and ORFs of unknown function, and protein-coding regions that are generally larger than those found in other animals. Not only does the Trichoplax mtDNA have characteristics of the mitochondrial genomes of known metazoan outgroups, such as chytrid fungi and choanoflagellates, but, more importantly, it shares derived features unique to the Metazoa. Phylogenetic analyses of mitochondrial proteins provide strong support for the placement of the phylum Placozoa at the root of the Metazoa.

Thrombolysis for stroke in the elderly.

INTRODUCTION: Systemic thrombolysis with intravenous recombinant tissue plasminogen activator (rt PA) for acute ischemic stroke had been licensed for patients up to 75 years in age in many European countries and was recently extended to 80 years. This age restriction results from the potential higher risk of cerebral bleeding in the elderly. The major rt PA trials included only 42 patients above 80 years showing a potential benefit from treatment. Further data is still rare. METHODS: Using our stroke database we identified all patients beyond 75 years with middle cerebral artery ischemia treated with intravenous rt PA in our stroke unit from 02/1999 until 07/2004. Clinical course and outcome until day 5 in addition to mortality after 3 and 6 months were analysed. RESULTS: Twenty-nine patients (80.8+/-4 years, 16 of them over 80 years old) met the inclusion criteria representing 21.2% of those receiving thrombolytic therapy. The median NIH-SS score on admission was 14 points. On day 5 after thrombolysis, 13/29 showed a good recovery (NIH-SS improvement >or=4 pts). The remaining exhibited only small or no benefit (n=11), deterioration (n=3) or died (n=2). A total of 3/29 patients developed non-symptomatic parenchymal hemorrhage or hemorrhagic transformation. One patient died due to space-occupying cerebral hemorrhage. Extracerebral bleeding was found in 3/29 requiring substitution in one. One other died for primary cardiac reasons. Median NIH-SS on day 5 was 10 points. Mortality after 3 and 6 months was 20.7%. We did not find factors predicting clinical outcome. Most importantly, there was no significant difference regarding outcome in patients 76--80 vs. 81--87 years old. DISCUSSION: Intravenous rt PA resulted in good neurological in-hospital outcome in almost 45% and six-months survival of almost 80% of the patients beyond 75 years. In 10.3% non-symptomatic and in 3.4% symptomatic cerebral bleeding was found. Thus, seniors beyond 75 and even beyond 80 years in good medical condition may benefit from systemic treatment with rt PA. Prospective studies are needed to clarify which part of the senior population might be most eligible for systemic thrombolysis.

The Trox-2 Hox/ParaHox gene of Trichoplax (Placozoa) marks an epithelial boundary.

Hox and ParaHox genes are implicated in axial patterning of cnidarians and bilaterians, and are thought to have originated by tandem duplication of a single "ProtoHox" gene followed by duplication of the resultant gene cluster. It is unclear what the ancestral role of Hox/ParaHox genes was before the divergence of Cnidaria and Bilateria, or what roles the postulated ProtoHox gene(s) played. Here we describe the full coding region, spatial expression and function of Trox-2, the single Hox/ParaHox-type gene identified in Trichoplax adhaerens (phylum Placozoa) and either a candidate ProtoHox or a ParaHox gene. Trox-2 is expressed in a ring around the periphery of Trichoplax, in small cells located between the outer margins of the upper and lower epithelial cell layers. Inhibition of Trox-2 function, either by uptake of morpholino antisense oligonucleotides or by RNA interference, causes complete cessation of growth and binary fission. We speculate that Trox-2 functions within a hitherto unrecognized population of possibly multipotential peripheral stem cells that contribute to differentiated cells at the epithelial boundary of Trichoplax.