Sphenopalatine Ganglion Stimulation to Augment Cerebral Blood Flow

Background and Purpose—

Many patients with acute ischemic stroke are not eligible for thrombolysis or mechanical reperfusion therapies due to contraindications, inaccessible vascular occlusions, late presentation, or large infarct core. Sphenopalatine ganglion (SPG) stimulation to enhance collateral flow and stabilize the blood-brain barrier offers an alternative, potentially more widely deliverable, therapy.

Methods—

In a randomized, sham-controlled, double-masked trial at 41 centers in 7 countries, patients with anterior circulation ischemic stroke not treated with reperfusion therapies within 24 hours of onset were randomly allocated to active SPG stimulation or sham control. The primary efficacy outcome was improvement beyond expectations on the modified Rankin Scale of global disability at 90 days (sliding dichotomy), assessed in the modified intention-to-treat population. The initial planned sample size was 660 patients, but the trial was stopped early when technical improvements in device placement occurred, so that analysis of accumulated experience could be conducted to inform a successor trial.

Results—

Among 303 enrolled patients, 253 received at least one active SPG or sham stimulation, constituting the modified intention-to-treat population (153 SPG stimulation and 100 sham control). Age was median 73 years (interquartile range, 64–79), 52.6% were female, deficit severity on the National Institutes of Health Stroke Scale was median 11 (interquartile range, 9–15), and time from last known well median 18.6 hours (interquartile range, 14.5–22.5). For the primary outcome, improved 3-month disability beyond expectations, rates in the SPG versus sham treatment groups were 49.7% versus 40.0%; odds ratio, 1.48 (95% CI, 0.89–2.47); P =0.13. A significant treatment interaction with stroke location (cortical versus noncortical) was noted, P =0.04. In the 87 patients with confirmed cortical involvement, rates of improvement beyond expectations were 50.0% versus 27.0%; odds ratio, 2.70 (95% CI, 1.08–6.73); P =0.03. Similar response patterns were observed for all prespecified secondary efficacy outcomes. No differences in mortality or serious adverse event safety end points were observed.

Conclusions—

SPG stimulation within 24 hours of onset is safe in acute ischemic stroke. SPG stimulation was not shown to statistically significantly improve 3-month disability above expectations, though favorable outcomes were nominally higher with SPG stimulation. Beneficial effects may distinctively be conferred in patients with confirmed cortical involvement. The results of this study need to be confirmed in a larger pivotal study.

Clinical Trial Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT03767192.

Phylogenetic relationships within the class Spirotrichea (Ciliophora) inferred from small subunit rRNA gene sequences

The small subunit rDNAs of five species belonging to the Euplotidae and eight species of the Oxytrichidae were sequenced to obtain a more detailed picture of the phylogenetic relationships within the Spirotrichea (Ciliophora). Various tree reconstruction algorhythms yielded nearly identical topologies. All Euplotidae were separated from the other Spirotrichea by a deep split. Further, a large genetic distance between the marine genus Moneuplotes and the freshwater species of Euplotoides was found. Differences between the methods used occurred only within the Oxytrichidae. Whereas the monophyly of the Stylonychinae was supported in all trees, the monophyly of the Oxytrichinae was not. However, the molecular data support the morphological and ontogenetic evidence that the pattern of 18 frontal-ventral-transversal cirri evolved in the stemline of the Oxytrichidae and was modified several times independently. Our results are also in agreement with taxonomic revisions: the separation of both Sterkiella nova from Oxytricha and Tetmemena pustulata from Stylonychia.

Analysis of the complete mitochondrial DNA sequence of the brachiopod terebratulina retusa places Brachiopoda within the protostomes

Brachiopod phylogeny is still a controversial subject. Analyses using nuclear 18SrRNA and mitochondrial 12SrDNA sequences place them within the protostomes but some recent interpretations of morphological data support a relationship with deuterostomes. In order to investigate brachiopod affinities within the metazoa further, we compared the gene arrangement on the brachiopod mitochondrial genome with several metazoan taxa. The complete (15 451 bp) mitochondrial DNA (mtDNA) sequence of the articulate brachiopod Terebratulina retusa was determined from two overlapping long polymerase chain reaction products. All the genes are encoded on the same strand and gene order comparisons showed that.only one major rearrangement is required to interconvert the T. retusa and Katharina tunicata (Mollusca: Polvplacophora) mitochondrial genomes. The partial mtDNA sequence of the prosobranch mollusc Littorina saxatilis shows complete congruence with the T. rehtusa gene arrangement with regard to the ribosomal and protein coding genes. This high similarity in gene arrangement is the first to be reported within the protostomes. Sequence analyses of mitochondrial protein coding genes also support a close relationship of the brachiopod with molluscs and annelids, thus supporting the clade Lophotrochozoa. Though being highly informative, sequence analyses of the mitochondrial protein coding genes failed to resolve the branching order within the lophotrochozoa.

Phylogenetic relationships between prostome and colpodean ciliates tested by small subunit rRNA sequences

We analyzed the phylogenetic relationships among the four ciliate classes, Prostomatea, Colpodea, Nassophorea, and Litostomatea, by small subunit ribosomal RNA gene sequence comparison to test several phylogenetic hypotheses that had been proposed for these classes, based on ultrastructural features. The complete coding regions of the prostomes, Prorodon teres and Coleps hirtus, and of the colpodean, Bursaria truncatella, were determined and compared to the database and the literature. The prostomes and colpodeans are strongly supported as monophyletic groups in all analyses. A sister-group relationship between prostomes and colpodeans is strongly supported by parsimony analyses and moderately supported by distance matrix analyses. There was no support for a close relationship between colpodeans and nassophoreans or between colpodeans and litostomes. In all analyses, these four classes branch late in the ciliate tree. This finding further supports the new view of ciliate phylogeny that so-called ancestral taxa, such as the "primitive" prostomes, are in fact derived and that so-called "highly evolved" groups, such as the heterotrichs, branch off very early in the ciliate tree.