Symptomatic hemorrhage after alteplase therapy not due to silent ischemia

BACKGROUND: Stroke thrombolysis-related intracerebral hemorrhage may occur remotely from the anatomical site of ischemia. One postulated mechanism for this is simultaneous multiple embolization with hemorrhage into a "silent" area of ischemia. RESULTS: A patient suffered a disabling stroke affecting the right cerebral hemisphere. He was treated with intravenous alteplase and underwent extensive early imaging with multimodal MRI. Several hours after treatment he developed a brainstem hemorrhage despite having no evidence of ischemia on DWI MRI in the brainstem. CONCLUSION: Not all occurrences of remote ICH after stroke thrombolysis are secondary to multiple emboli with silent ischemia

Inter-annual decrease in pulse rate and peak frequency of Southeast Pacific blue whale song types

The decrease in the frequency of two southeast Pacific blue whale song types was examined over decades, usingacoustic data from several different sources ranging between the Equator and Chilean Patagonia. The pulse rate ofthe song units as well as their peak frequency were measured using two different methods (summed auto-correlationand Fourier transform). The sources of error associated with each measurement were assessed. There was a lineardecline in both parameters for the more common song type (southeast Pacific song type n ◦ 2). An abbreviated analysisalso showed a frequency decline in the scarcer southeast Pacific song type n ◦ 1 between 1970 to 2014, revealing thatboth song types are declining at similar rates. We discussed the use of measuring both pulse rate and peak frequencyto examine the frequency decline. Finally, a comparison of the rates of frequency decline with other song typesreported in the literature is presented.La décroissance en fréquence des deux chants de baleine bleue de l'océan pacifique sud est est examiné sur plusieurs décennies en utilisant comme source des données acoustiques de l'Equateur à la Patagonie chilienne. La fréquence de pulsation et la fréquence pic des signaux sont mesurés en utilisant deux méthodes distinctes (auto-corrélation sommée et transformée de Fourier rapide). Les sources d'erreur associées à chaque mesure sont estimées. Il y a un déclin linéaire de ces deux fréquences pour le chant le plus commun de cette zone (chant du Pacifique Sud Est n°2, SEP2). Un analyse plus rapide montre aussi une baisse linéaire, entre 1970 et 2014, de la fréquence du chant SEP1, plus rarement enregistré dans cette zone. Ces deux baisses ont des amplitudes similaires. L'intérêt de mesurer la fréquence de pulsation et la fréquence pic de façon concomitante est estimé. Enfin, une comparaison globale des déclins en fréquence de tous les types de chants de baleines bleues est fournie

The effect of rapamycin treatment on cerebral ischemia: A systematic review and meta-analysis of animal model studies

Background:Amplifying endogenous neuroprotective mechanisms is a promising avenue for stroke therapy. One target is mammalian target of rapamycin (mTOR), a serine/threonine kinase regulating cell proliferation, cell survival, protein synthesis, and autophagy. Animal studies investigating the effect of rapamycin on mTOR inhibition following cerebral ischemia have shown conflicting results.Aim:To conduct a systematic review and meta-analysis evaluating the effectiveness of rapamycin in reducing infarct volume in animal models of ischemic stroke.Summary of review:Our search identified 328 publications. Seventeen publications met inclusion criteria (52 comparisons: 30 reported infarct size and 22 reported neurobehavioral score). Study quality was modest (median 4 of 9) with no evidence of publication bias. The point estimate for the effect of rapamycin was a 21.6% (95% CI, 7.6%–35.7% p Conclusion:Low-dose rapamycin treatment may be an effective therapeutic option for stroke. Modest study quality means there is a potential risk of bias. We recommend further high-quality preclinical studies on rapamycin in stroke before progressing to clinical trials

Growth differentiation factor-11 causes neurotoxicity during ischemia in vitro

Age-related neuronal dysfunction can be overcome by circulating factors present inyoung blood. Growth differentiation factor-11 (GDF-11), a systemic factor that declineswith age, can reverse age-related dysfunction in brain, heart and skeletal muscle. Giventhat age increases susceptibility to stroke, we hypothesized that GDF-11 may be directlyprotective to neurons following ischemia. Primary cortical neurons were isolated fromE18 Wistar rat embryos and cultured for 7–10 days. Neurons were deprived of oxygenand glucose (OGD) to simulate ischemia. Neuronal death was assessed by lactatedehydrogenase, propidium iodide or CellToxTMgreen cytotoxicity assays. 40 ng/mLGDF-11 administration during 2 h OGD significantly increased neuronal death following24 h recovery. However, GDF-11 pre-treatment did not affect neuronal death during 2 hOGD. GDF-11 treatment during the 24 h recovery period after 2 h OGD also did notalter death. Real-time monitoring for 24 h revealed that by 2 h OGD, GDF-11 treatmenthad increased neuronal death which remained raised at 24 h. Co-treatment of 1µMSB431542 (ALK4/5/7 receptor inhibitor) with GDF-11 prevented GDF-11 neurotoxicityafter 2 h OGD and 24 h OGD. Transforming growth factor beta (TGFβ) did not increaseneuronal death to the same extent as GDF-11 following OGD. GDF-11 neurotoxicity wasalso exhibited following neuronal exposure to hydrogen peroxide. These results revealfor the first time that GDF-11 is neurotoxic to primary neurons in the acute phase ofsimulated stroke through primarily ALK4 receptor signaling

A double-blind, randomized, multicenter, Italian study of frovatriptan versus rizatriptan for the acute treatment of migraine

The objective of this study was to assess patient satisfaction with acute treatment of migraine with frovatriptan or rizatriptan by preference questionnaire. 148 subjects with a history of migraine with or without aura (IHS 2004 criteria), with at least one migraine attack per month in the preceding 6 months, were enrolled and randomized to frovatriptan 2.5 mg or rizatriptan 10 mg treating 1–3 attacks. The study had a multicenter, randomized, double-blind, cross-over design, with treatment periods lasting <3 months. At the end of the study, patients assigned preference to one of the treatments using a questionnaire with a score from 0 to 5 (primary endpoint). Secondary endpoints were pain-free and pain relief episodes at 2 h, and recurrent and sustained pain-free episodes within 48 h. 104 of the 125 patients (83%, intention-to-treat population) expressed a preference for a triptan. The average preference score was not significantly different between frovatriptan (2.9 ± 1.3) and rizatriptan (3.2 ± 1.1). The rates of pain-free (33% frovatriptan vs. 39% rizatriptan) and pain relief (55 vs. 62%) episodes at 2 h were not significantly different between the two treatments. The rate of recurrent episodes was significantly (p < 0.001) lower under frovatriptan (21 vs. 43% rizatriptan). No significant differences were observed in sustained pain-free episodes (26% frovatriptan vs. 22% rizatriptan). The number of patients with adverse events was not significantly different between rizatriptan (34) and frovatriptan (25, p = NS). The results suggest that frovatriptan has a similar efficacy to rizatriptan, but a more prolonged duration of action

Ion implantation in nanodiamonds: Size effect and energy dependence

Nanoparticles are ubiquitous in nature and are increasingly important for technology. They are subject to bombardment by ionizing radiation in a diverse range of environments. In particular, nanodiamonds represent a variety of nanoparticles of significant fundamental and applied interest. Here we present a combined experimental and computational study of the behaviour of nanodiamonds under irradiation by xenon ions. Unexpectedly, we observed a pronounced size effect on the radiation resistance of the nanodiamonds: particles larger than 8 nm behave similarly to macroscopic diamond (i.e. characterized by high radiation resistance) whereas smaller particles can be completely destroyed by a single impact from an ion in a defined energy range. This latter observation is explained by extreme heating of the nanodiamonds by the penetrating ion. The obtained results are not limited to nanodiamonds, making them of interest for several fields, putting constraints on processes for the controlled modification of nanodiamonds, on the survival of dust in astrophysical environments, and on the behaviour of actinides released from nuclear waste into the environment

Building Babies - Chapter 16

In contrast to birds, male mammals rarely help to raise the offspring. Of all mammals, only among rodents, carnivores, and primates, males are sometimes intensively engaged in providing infant care (Kleiman and Malcolm 1981). Male caretaking of infants has long been recognized in nonhuman primates (Itani 1959). Given that infant care behavior can have a positive effect on the infant’s development, growth, well-being, or survival, why are male mammals not more frequently involved in “building babies”? We begin the chapter defining a few relevant terms and introducing the theory and hypotheses that have historically addressed the evolution of paternal care. We then review empirical findings on male care among primate taxa, before focusing, in the final section, on our own work on paternal care in South American owl monkeys (Aotus spp.). We conclude the chapter with some suggestions for future studies.Deutsche Forschungsgemeinschaft (HU 1746/2-1) Wenner-Gren Foundation, the L.S.B. Leakey Foundation, the National Geographic Society, the National Science Foundation (BCS-0621020), the University of Pennsylvania Research Foundation, the Zoological Society of San Dieg