Exploring Reperfusion Following Endovascular Thrombectomy.

Background and Purpose- Cerebral perfusion in acute ischemic stroke patients is often assessed before endovascular thrombectomy (EVT), but rarely after. Perfusion data obtained following EVT may provide additional prognostic information. We developed a tool to quantitatively derive perfusion measurements from digital subtraction angiography (DSA) data and examined perfusion in patients following EVT. Methods- Source DSA images from acute anterior circulation stroke patients undergoing EVT were retrospectively assessed. Following deconvolution, maps of mean transit time (MTT) were generated from post-EVT DSA source data. Thrombolysis in Cerebral Infarction grades and MTT in patients with and without hemorrhagic transformation (HT) at 24 hours were compared. Receiver operating characteristic modeling was used to classify the presence/absence of HT at 24 hours by MTT. Results- Perfusion maps were generated in 50 patients using DSA acquisitions that were a median (interquartile range) of 9 (8-10) seconds in duration. The median post-EVT MTT within the affected territory was 2.6 (2.2-3.3) seconds. HT was observed on follow-up computed tomography in 16 (32%) patients. Thrombolysis in Cerebral Infarction grades did not differ in patients with HT from those without (P=0.575). Post-EVT MTT maps demonstrated focal areas of hyperperfusion (n=8) or persisting hypoperfusion (n=3) corresponding to the regions where HT later developed. The relationship between MTT and HT was U-shaped; HT occurred in patients at both the lowest and highest extremes of MTT. An MTT threshold <2 or >4 seconds was 81% sensitive and 94% specific for classifying the presence of HT at follow-up. Conclusions- Perfusion measurements can be obtained using DSA perfusion with minimal changes to current stroke protocols. Perfusion imaging post-recanalization may have additional clinical utility beyond visual assessment of source angiographic images alone.

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing-like attacks in a pediatric patient found to have a pontine capillary telangiectasia and developmental venous anomaly: A case report exploring the root of the problem.

Introduction Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)-like attacks are rarely reported in the pediatric population and may remain undiagnosed and under-investigated as a result. Case presentation We present a case of a 15-year-old male with intermittent, episodic, right-sided brief headaches most in keeping with SUNCT, initially diagnosed as paroxysmal hemicrania, but with no response to indomethacin. The pain was likewise not responsive to typical migraine treatments or steroids. Management and outcome Contrast-enhanced magnetic resonance imaging demonstrated a right pontine capillary telangiectasia with an associated developmental venous anomaly that was adjacent to the root of the right trigeminal nerve. Differential diagnosis included first division trigeminal neuralgia with autonomic features. The patient's pain was partially alleviated by oxygen administration and responded well to carbamazepine; he remained pain free on carbamazepine a year later. Conclusion This case highlights the diagnostic dilemma of differentiating SUNCT from trigeminal neuralgia with autonomic features, both of which are rare diagnoses in pediatric patients, and the importance of appropriate neuroimaging to rule out secondary causes in patients presenting with trigeminal autonomic cephalalgias, recognizing that abnormalities identified on neuroimaging, such as vessels adjacent to the trigeminal nerve, may not be causative findings.

Acute myocardial infarction spurred by myopericarditis in a young female patient: Coxsackie B2 to blame.

Myocardial virus infection may mimic but also trigger acute myocardial infarction.The present paper reports an exceedingly rare presentation of an acute myocardial infarction in a very young female associated with Coxsackie B2 virus infection. A 17-year-old woman with no prior medical history presented to the Cardiac Intensive Care unit with chest pain, ST segment elevation and increased cardiac troponin with pericardial effusion one week after experiencing febrile viral gastroenteritis. Given the age and health of the patient, myocarditis was initially presumed. Coronary angiography and cardiac magnetic resonance imaging studies, however, demonstrated an acute posterior myocardial infarction related to a right coronary artery thrombosis. Serological studies disclosed a concurrent Coxsackie B2 virus infection. The patient made a successful recovery with subsequent minor left ventricular dysfunction at long-term follow-up. Coxsackie B2 myocarditis might have triggered a coronary artery spasm and subsequent thrombosis.

Phylogenetic and primary sequence characterization of cathepsin B cysteine proteases from the oxymonad flagellate Monocercomonoides.

Cysteine proteases are crucial for general lysosomal function and for the pathogenic mechanisms of many protistan parasites. Cathepsin B cysteine proteases are currently defined by the presence of the "occluding loop" motif and have been best characterized from humans and their parasites. Though related to a variety of pathogenic excavate flagellates, oxymonads are themselves commensals. While studying this cell biologically aberrant protist lineage, we identified 11 different cathepsin B homologues. These were found to be expressed, at comparable levels to common house-keeping genes, such as elongation factor 1-alpha, alpha-tubulin, beta-tubulin, and glyceraldehyde phosphate dehydrogenase. Primary structure examination of the cathepsin B homologues identified putative signal peptide sequences, and the pre-, pro-, and mature domains of the protein. However, the occluding loop motif was either partially or entirely absent. Comparative genomics, sequence alignment, and phylogenetics of cathepsin sequences from across the diversity of eukaryotes demonstrated that absence of the occluding loop is not a feature exclusive to oxymonads, but is relatively common, suggesting that the "occluding loop" should no longer be used as the defining feature of the cathepsin B subfamily. Overall, this report identifies an abundant protein family in oxymonads, and provides insight both into the evolution and classification of cathepsin B cysteine proteases.

Reconstructing the mosaic glycolytic pathway of the anaerobic eukaryote Monocercomonoides.

All eukaryotes carry out glycolysis, interestingly, not all using the same enzymes. Anaerobic eukaryotes face the challenge of fewer molecules of ATP extracted per molecule of glucose due to their lack of a complete tricarboxylic acid cycle. This may have pressured anaerobic eukaryotes to acquire the more ATP-efficient alternative glycolytic enzymes, such as pyrophosphate-fructose 6-phosphate phosphotransferase and pyruvate orthophosphate dikinase, through lateral gene transfers from bacteria and other eukaryotes. Most studies of these enzymes in eukaryotes involve pathogenic anaerobes; Monocercomonoides, an oxymonad belonging to the eukaryotic supergroup Excavata, is a nonpathogenic anaerobe representing an evolutionarily and ecologically distinct sampling of an anaerobic glycolytic pathway. We sequenced cDNA encoding glycolytic enzymes from a previously established cDNA library of Monocercomonoides and analyzed the relationships of these enzymes to those from other organisms spanning the major groups of Eukaryota, Bacteria, and Archaea. We established that, firstly, Monocercomonoides possesses alternative versions of glycolytic enzymes: fructose-6-phosphate phosphotransferase, both pyruvate kinase and pyruvate orthophosphate dikinase, cofactor-independent phosphoglycerate mutase, and fructose-bisphosphate aldolase (class II, type B). Secondly, we found evidence for the monophyly of oxymonads, kinetoplastids, diplomonads, and parabasalids, the major representatives of the Excavata. We also found several prokaryote-to-eukaryote as well as eukaryote-to-eukaryote lateral gene transfers involving glycolytic enzymes from anaerobic eukaryotes, further suggesting that lateral gene transfer was an important factor in the evolution of this pathway for denizens of this environment.