Abstract W P244: Effect of Remote Limb Ischemic Conditioning on CBF as Measured by Arterial Spin Labeling in Human Stroke

Background: Remote limb ischemic conditioning (RLIC) is a promising treatment for ischemic stroke. We have previously shown that RLIC increases cerebral blood flow, reduces infarct size, and improves outcome in a murine thromboembolic stroke model (Hoda N et al. Stroke. 2012; 43:2794). We hypothesized that RLIC will increase CBF in hypoperfused areas in acute stroke patients as detected by MRI Arterial Spin Labeling (ASL)

Methods: Patients with an acute ischemic stroke within 14 days and with a persistent mismatch defined by a perfusion defect measured by ASL that was at least 20% larger than the area of infarction as measured by diffusion weighted imaging (DWI) were eligible. Patients underwent 4 cycles of blood pressure cuff inflation (x200 mm Hg) for 5 minutes and deflation for 5 minutes on the leg or arm, 1- 2 times per day. MRI ASL, DWI, and 3D T1-weighted Fast Spoiled Gradient-Echo (FSPGR) images were taken before and 60 minutes after the last cycle of RLIC to measure CBF. Two neuroradiologists analyzed the images.

Results: After 3 of 4 RLIC sessions, the CBF improved and the mismatch decreased by at least 15%. In the one patient without a reduction in mismatch, the RLIC was performed on the arm and not the leg.

Conclusions: 1.) RLIC increased CBF as measured by ASL in stroke patients with a persistent diffusion-perfusion mismatch. 2.) Since it can be repeated multiple times on the same patient, ASL may be a useful biomarker of the conditioning response in humans. 3.) Further work in a larger sample of patients is needed to define the optimal regimen of RLIC and to determine the utility of ASL as a biomarker.

Abstract T P78: Remote Ischemic Conditioning (RIC), a Combined Regimen of Per- and Post- Conditionings (RIPerC and RIPostC), Provides Long-term Motor and Cognitive Benefits in Murine Embolic Stroke Model (eMCAO)

The majority of stroke sufferers need rehabilitation and institutional grade long-term care even after IV-tPA therapy. RIC therapy is easier to perform, safe, promising and ideal for post-stroke rehabilitation. Long-term benefits of RIC have never been reported after eMCAO. Our objective here was to determine if RIC provides long-term behavioral benefits with and without IV-tPA.

Methods: eMCAO was induced in WT C57/Bl male mice (~6-mo old). Animals were randomized for the treatments (RIC, NO vs. YES; and IV-tPA, NO vs. YES, n=20/group) after eMCAO. Either IV-tPA (10 mg/kg b.wt.) or IV-saline was infused at 4 hours post-eMCAO. RIC was performed non-invasively on the left hind limb at 2, 8 and 24 hours post-eMCAO, followed by every alternate day till day 15. Neurological deficit score (NDS), and adhesive tape test were performed on day 2, 7 and 15 post-stroke to assess the motor function. Cognitive function was assessed by novel object recognition (NOR) test on day 8 and 16 post-stroke.

Results: RIC improved NDS and sensorimotor functions significantly (p<0.05) on day 2 and 7 with and without IV-tPA, but late IV-tPA alone was not effective. On day 15, there was a trend towards improved motor function in RIC treated groups, which was not significant. However, cognitive function was improved significantly (p<0.05) on day 8 and 16 in RIC-treated groups with and without IV-tPA. IV-tPA alone did not provide any significant improvement in cognition. RIC also improved the survival with and without IV-tPA.

Conclusion: RIC is a promising therapy for improved motor and cognitive functions during post-stroke rehabilitation and provides survival benefits. Further work is needed to determine the potential of RIC in aged animals and in animals with comorbidities.

Rapamycin up-regulation of autophagy reduces infarct size and improves outcomes in both permanent MCAL, and embolic MCAO, murine models of stroke

BACKGROUND AND PURPOSE

The role of autophagy in response to ischemic stroke has been confusing with reports that both enhancement and inhibition of autophagy decrease infarct size and improve post-stroke outcomes. We sought to clarify this by comparing pharmacologic modulation of autophagy in two clinically relevant murine models of stroke.

METHODS

We used rapamycin to induce autophagy, and chloroquine to block completion of autophagy, by treating mice immediately after stroke and at 24 hours post-stroke in two different models; permanent Middle Cerebral Artery Ligation (MCAL), which does not allow for reperfusion of distal trunk of middle cerebral artery, and Embolic Clot Middle Cerebral Artery Occlusion (eMCAO) which allows for a slow reperfusion similar to that seen in most human stroke patients. Outcome measures at 48 hours post-stroke included infarct size analysis, behavioral assessment using Bederson neurological scoring, and survival.

RESULTS

Chloroquine treatment reduced the lesion size by approximately 30% and was significant only in the eMCAO model, where it also improved the neurological score, but did not increase survival. Rapamycin reduced lesion size by 44% and 50% in the MCAL and eMCAO models, respectively. Rapamycin also improved the neurological score to a greater degree than chloroquine and improved survival.

CONCLUSIONS

While both inhibition and enhancement of autophagy by pharmacological intervention decreased lesion size and improved neurological scores, the enhancement with rapamycin showed a greater degree of improvement in outcomes as well as in survival. The protective action seen with chloroquine may be in part due to off-target effects on apoptosis separate from blocking lysosomal activity in autophagy. We conclude pharmacologic induction of autophagy is more advantageous than its blockade in physiologically-relevant permanent and slow reperfusion stroke models.

Minocycline development for acute ischemic stroke

Minocycline, a tetracycline antibiotic, has shown anti-inflammatory, anti-apoptotic, and neuroprotective effects in many models of cerebral ischemia and neurodegenerative disease. Its high penetration of the blood-brain barrier, good safety profile, and delayed therapeutic window make it an ideal candidate for use in stroke. In animal models, minocycline reduced infarct size and improved neurologic outcome when administered acutely, with similar neuroprotective benefits seen following delayed administration. To date, two early phase clinical trials have shown minocycline to be safe and potentially effective in acute ischemic stroke, alone or in combination with tissue plasminogen activator. A large efficacy clinical trial is now needed to confirm previous studies, allow for subgroup analysis, and pinpoint the potential place for minocycline in acute stroke therapy.

Gait analysis in a pre- and post-ischemic stroke biomedical pig model

Severity of neural injury including stroke in human patients, as well as recovery from injury, can be assessed through changes in gait patterns of affected individuals. Similar quantification of motor function deficits has been measured in rodent animal models of such injuries. However, due to differences in fundamental structure of human and rodent brains, there is a need to develop a large animal model to facilitate treatment development for neurological conditions. Porcine brain structure is similar to that of humans, and therefore the pig may make a more clinically relevant animal model. The current study was undertaken to determine key gait characteristics in normal biomedical miniature pigs and dynamic changes that occur post-neural injury in a porcine middle cerebral artery (MCA) occlusion ischemic stroke model. Yucatan miniature pigs were trained to walk through a semi-circular track and were recorded with high speed cameras to detect changes in key gait parameters. Analysis of normal pigs showed overall symmetry in hindlimb swing and stance times, forelimb stance time, along with step length, step velocity, and maximum hoof height on both fore and hindlimbs. A subset of pigs were again recorded at 7, 5 and 3 days prior to MCA occlusion and then at 1, 3, 5, 7, 14 and 30 days following surgery. MRI analysis showed that MCA occlusion resulted in significant infarction. Gait analysis indicated that stroke resulted in notable asymmetries in both temporal and spatial variables. Pigs exhibited lower maximum front hoof height on the paretic side, as well as shorter swing time and longer stance time on the paretic hindlimb. These results support that gait analysis of stroke injury is a highly sensitive detection method for changes in gait parameters in pig.

Serendipitous recanalization of basilar artery occlusion

OBJECTIVE

To describe a case of recanalization of a basilar artery occlusion with intravenous (IV) tenecteplase.

CASE

A 74-year-old man with a history of cardiomyopathy presented to an outside hospital with acute vertigo, dysarthria, gaze deviation, and ataxia. Computerized tomography arteriography demonstrated occlusion of the proximal basilar artery. IV tissue plasminogen activator was ordered; however, the patient received a cardiac dose of IV tenecteplase. The patient was transferred to our facility, whereby symptoms resolved, and repeat computerized tomography arteriography displayed recanalization of the basilar artery.

CONCLUSIONS

Tenecteplase has enhanced biochemical and pharmacokinetic properties that may be ideal for treatment of basilar artery occlusion and should be further investigated in a randomized clinical trial.

Timeliness of intravenous thrombolysis via telestroke in Georgia

BACKGROUND AND PURPOSE

Through 2-way live video and audio communication, telestroke enhances urgent treatment of patients with acute stroke in emergency departments (EDs) without immediate access to on-site specialists. To assess for opportunities to shorten the door to thrombolysis time, we measured multiple time intervals in a telestroke system.

METHODS

We retrospectively analyzed 115 records of consecutive acute stroke patients treated with intravenous thrombolysis during a 20-month period via a statewide telestroke system in 17 EDs in Georgia. On the basis of times documented in the telestroke system, we calculated the time elapsed between the following events: ED arrival, telestroke patient registration, start of specialist consultation, head computed tomography, thrombolysis recommendation, and thrombolysis initiation.

RESULTS

The most conspicuous delay was from ED arrival to telestroke patient registration (median, 39 minutes; interquartile range, 21-56). Median time from ED arrival to thrombolysis initiation was 88 minutes, interquartile range 75 to 105. Thrombolysis was initiated within 60 minutes from ED arrival in 13% of patients.

CONCLUSIONS

The greatest opportunity to expedite acute thrombolysis via telestroke is by shortening the time from ED arrival to telestroke patient registration.

A double-blind placebo-controlled clinical evaluation of MultiStem for the treatment of ischemic stroke

BACKGROUND

There is growing interest in neurorestorative and reparative therapies after acute stroke. MultiStem is an allogeneic cell therapy treatment comprising a population of multipotent adherent bone marrow cells that has shown safety in clinical trials of myocardial infarction and graft vs. host disease, as well as preclinical evidence of activity in stroke and other neurological damage models. MultiStem is now being evaluated in a clinical trial in patients that have suffered an ischemic stroke, in which the product is administered intravenously 24-36 h after the ischemic event.

METHODS

The Phase 2 randomized, double-blind, placebo-controlled, multicenter dose-escalation trial will consist of three treatment cohorts, including a placebo group, and two treatment groups involving dose tiers of either 400 million or 1200 million cells per patient. Patients will be treated at 24-36 h after stroke. The two primary objectives are to determine the highest well-tolerated and safe single dose of MultiStem up to a maximum of 1200 million total cells in subjects with ischemic stroke and to determine the efficacy of MultiStem on functional outcome in subjects with stroke as measured by the modified Rankin Scale at 90 days. Patients will also be evaluated using the National Institutes of Health Stroke Scale and Barthel Index. The study will explore other aspects including, uniquely, the measurement of spleen size after stroke by magnetic resonance imaging or computed tomography imaging.

CONCLUSIONS AND FUTURE DIRECTION

If MultiStem is safe and there is a signal of efficacy, a late stage phase IIb-III trial is planned.

The history and future of telestroke

This Review focuses on the application of telemedicine to the care of patients with acute stroke (telestroke), from the prehospital setting through hospitalization. Telestroke has grown remarkably in the past decade and has entered mainstream care for patients with acute stroke. Telestroke enables such patients to be remotely evaluated, thereby allowing optimal treatment and management even in clinically underserved areas and removing geographical disparities in access to expert care. Telestroke systems enable thrombolytic treatment to be administered in community and rural hospitals, and facilitate the appropriate transfer of patients with complex conditions (who require critical care services and neurosurgical or intra-arterial interventions) to a comprehensive stroke centre. Decision-analytic models show that telestroke is cost-effective from both a societal and a hospital perspective. Limitations to the use of telestroke in the USA include the need for state licensing and credentialling of physicians, and the technical requirements of a minimum network bandwidth (which is still lacking in some regions). However, the opportunity exists for telestroke to become the backbone of an electronic stroke unit and to be used to identify and enrol patients in clinical trials of acute stroke treatment. The use of telestroke in the prehospital setting has been hampered by limited telecommunication availability, but these problems might be mitigated by fourth-generation cellular data networks.

Simplified modified Rankin Scale questionnaire correlates with stroke severity

OBJECTIVE

To further validate the simplified modified Rankin Scale questionnaire (smRSq), we compare it here to a well-established predictor of functional outcome after stroke, the initial stroke severity.

DESIGN

Retrospective correlation analysis.

PARTICIPANTS

Forty patients identified from a registry of stroke patients treated with intravenous tissue plasminogen activator.

SETTING

Community and 17 hospital Emergency Departments within a web-based telestroke network throughout the state of Georgia, USA.

MEASURES

Five certified raters assessed the initial stroke severities with the National Institutes of Health Stroke Scale (NIHSS) via the telestroke system. Over a 20 month period, one certified rater, unaware of the NIHSS scores, attempted to contact each patient in the registry to assess their functional outcomes with the smRSq via telephone. We analyzed patients who had the smRSq assessment at least three months after stroke.

RESULTS

Forty of 120 registered patients were contacted and qualified for this study. The baseline clinical characteristics of the 40 analyzed and the 80 disqualified patients were similar. The correlation between the initial NIHSS and the smRSq was good (r = 0.69, R(2) = 0.47, P < 0.001).

CONCLUSIONS

The good correlation of the smRSq with the initial stroke severity further confirms the smRSq validity in assessing functional outcome after stroke.

Teleneurology applications: Report of the Telemedicine Work Group of the American Academy of Neurology

OBJECTIVE

To review current literature on neurology telemedicine and to discuss its application to patient care, neurology practice, military medicine, and current federal policy.

METHODS

Review of practice models and published literature on primary studies of the efficacy of neurology telemedicine.

RESULTS

Teleneurology is of greatest benefit to populations with restricted access to general and subspecialty neurologic care in rural areas, those with limited mobility, and those deployed by the military. Through the use of real-time audio-visual interaction, imaging, and store-and-forward systems, a greater proportion of neurologists are able to meet the demand for specialty care in underserved communities, decrease the response time for acute stroke assessment, and expand the collaboration between primary care physicians, neurologists, and other disciplines. The American Stroke Association has developed a defined policy on teleneurology, and the American Academy of Neurology and federal health care policy are beginning to follow suit.

CONCLUSIONS

Teleneurology is an effective tool for the rapid evaluation of patients in remote locations requiring neurologic care. These underserved locations include geographically isolated rural areas as well as urban cores with insufficient available neurology specialists. With this technology, neurologists will be better able to meet the burgeoning demand for access to neurologic care in an era of declining availability. An increase in physician awareness and support at the federal and state level is necessary to facilitate expansion of telemedicine into further areas of neurology.

Abstract WP101: Localization of Stereotactic Injections of Human iNP cells One Week Post-MCAL Stroke is Critical in Reducing Stroke Lesion Injury

There is interest in therapeutic approaches to improve stroke injuries beyond the current 4.5 hour window of opportunity available for tPA treatment. We are interested in determining if neural progenitor cells can provide protection one week out from a stroke injury, and if the location of the cells relative to the core or penumbra of the injury site is important.

Methods: We used a unilateral permanent middle cerebral artery ligation (MCAL) stroke injury model in C57B6 mice (male 3 months old) that generates a modest cortical lesion with limited subcortical injury. A single 3 ul Stereotactic injection was made either in the stroke core, or outside the injury site penumbra under the ipsilateral hippocampus. We injected 100,000 neural progenitor cells (iNPs) differentiated from induced pluripotent stem cells derived from human fibroblasts. Previous work showed that injection in a matrix enhanced iNP survival, therefore, the cells were injected either in a hydrogel matrix (n=4) or in matrigel (n=5) one week post-MCAL. Hydrogel (n=5) and Matrigel (n=4) only control groups were also used. Mice were sacrificed three weeks post-MCAL (two weeks post-transplant) and evaluated for lesion size as a percent of cortex.

Results: Mice that received stem cells placed into the core of the lesion, regardless of the specific matrix, had significantly smaller cortical lesions (p=0.0021) than those who did not receive stem cells (hydrogel alone control 36.0% mean cortical lesion (10.7% SD); Hydrogel + iNP cells 15.6% (3.1%); Matrigel alone control 30.4% (10.0%), matrigel + iNP cells 19.4% (8.6%). There was no difference between the controls: saline only, matrigel only, or hydrogel only. Using the same approach a second set of mice received 100,000 iNP cells outside of the lesion site, below the ipsilateral hippocampus (matrigel + iNPs (n=9), matrigel alone (n=9), or saline (n=8). In contrast there was no reduction in lesion size.

Conclusion: This suggests that iNPs in the region of greatest injury can provide protection even one week following stroke, but that these effects are spatially limited. Future studies will focus on aged male and female populations.

Abstract WP106: Remote Ischemic Per-Conditioning (RIPerC) is Protective after Embolic Stroke in Ovariectomized Female Mice

RIPerC by sub-lethal limb ischemia is protective in multiple animal models of reperfusion injury including stroke, and in certain clinical trials. We reported that RIPerC is effective with and without IV-tPA after embolic stroke (eMCAO) in young male mice ( Hoda et al; Stroke. 2012: MS ID# 660373; in press ). Our objective here was to determine if RIPerC is also effective in ovariectomized (OVX) female mice.

Methods: eMCAO was induced in 68 WT C57/BL OVX females by injecting fibrin-rich clot into the right hemisphere, and occlusion was confirmed with laser Doppler instruments (LDI). Animals were randomized for the treatments after eMCAO and outcome measurements were blindly performed. RIPerC therapy or sham procedure was performed non-invasively using a rodent blood pressure cuff on the left hind limb at 2 hrs post-eMCAO (4 cycles/ each cycle 10 minutes/ 10 minutes interval). Either IV-tPA or IV-saline was infused at 4 hours post-eMCAO. Cerebral blood flow (CBF) by LDI and plasma nitric oxide (NO) was measured at 6 hours post-eMCAO. At 24 hours post-eMCAO, Bederson neurological deficit score (NDS) was assessed, and infarct size was estimated by TTC-staining.

Results: RIPerC alone significantly improved the CBF, plasma NO level and NDS (P<0.05), and also reduced the infarct size (Relative reduction ~31%; P<0.01) as compared to eMCAO control group. IV-tPA alone at 4 hours post-eMCAO neither improved NDS nor reduced the infarct, although IV-tPA improved the CBF as compared to eMCAO control group due to its recanalization effects (P<0.01). In comparison to IV-tPA alone treatment, RIPerC combination with IV-tPA did not show significant improvement in CBF. But when compared to eMCAO control group, the combination therapy showed further improvements in CBF at 6 hours post-eMCAO (P<0.001). Combination therapy also significantly improved the NDS (P<0.05) and reduced the infarct size (Relative reduction ~21%; P<0.05) as compared to eMCAO control group at 24 hours post-eMCAO.

Conclusion: RIPerC is an effective therapy after eMCAO in females. Further work is needed to determine the effectiveness of RIPerC in aged animals and in animals with comorbidities.

Abstract WMP67: Plasminogen Deficiency And Gender Dimorphism After Thromboembolic Stroke

Background: Stroke is a sex dimorphic disease with males and post-menopausal females having worse outcomes. Plasminogen (Pg) system plays a major role in post-stroke outcomes, affecting clot lysis and MMP-9 regulation. Activation of MMP-9 occurs by both Pg-dependent and Pg-independent mechanisms. However, the role of Pg-dependent molecular pathways in stroke remains unclear. The aim of this work was to determine if there is a sex-specific change in post-stroke neurologic outcomes in mice with Pg deficiency.

Methods: Pg knockout (Pg -/- ) and wild type (Pg +/+ ) mice of both sexes (n=8-14 animals/group; 26±4 weeks old) were subjected to embolic stroke. At 24 hours, behavioral evaluation, infarct area and edema volume were assessed.

Results: Plasminogen deficiency caused pathological fibrin deposition in the microcirculation, inducing a similar systemic inflammatory response in males and females with significantly increased levels of monocytes (1.7-fold, p<0.01) and granulocytes (3.5-fold, p<0.001) in the circulation compared with Pg +/+ mice. Moreover, all pro-thrombotic Pg -/- mice had microcytic anemia due to low red blood cell volume (36.7 fl vs. 41.6 fl, p<0.001). Pg -/- females had lower estrogen levels compared with Pg +/+ females (10.2±12.6 pg/ml vs. 31.5±51 pg/ml; p=0.23). Pg deficiency did not affect the level of MMP-9 in the brain nor in the circulation. Despite the similar levels of systemic pro-thrombotic inflammation in Pg -/- mice of both sexes, we observed a significant gender disparity in stroke outcomes. Pg deficiency in males improved behavioral outcomes (1.6 vs. 3.2; p<0.001), reduced infarct size (32.8% vs. 43.1%; p<0.05) and edema volume (5.7% vs. 15.4%; p<0.001) compared with Pg -/- mice. On the other hand, Pg -/- females had a higher mortality (60% vs. 18%) and a poorer neurologic score (4.6 versus 2.3; p<0.001) due to severe brain injury with an increased volume of infarct (64.8% vs. 19.9%; p<0.001) and edema (13.3% vs. 5.6%; p<0.05) compared with Pg +/+ females.

Conclusion: Unlike males, Pg -/- females had disproportionately poor outcomes compared with Pg +/+ females. Our data demonstrates that Pg -/- female mice may represent an experimental model that mimics females in an early menopausal stage with chronic pro-thrombotic disease.

Permeating the blood brain barrier and abrogating the inflammation in stroke: implications for stroke therapy

Cell therapy has been shown as a potential treatment for stroke and other neurological disorders. Human umbilical cord blood (HUCB) may be a promising source of stem cells for cell therapy. The most desired outcomes occur when stem cells cross the blood brain barrier (BBB) and eventually reach the injured brain site. We propose, from our previous studies, that mannitol is capable of disrupting the BBB, allowing the transplanted cells to enter the brain from the periphery. However, when the BBB is compromised, the inflammatory response from circulation may also be able to penetrate the brain and thus may actually exacerbate the stroke rather than afford therapeutic effects. We discuss how an NF-kB decoy can inhibit the inflammatory responses in the stroke brain thereby reducing the negative effects associated with BBB disruption. In this review, we propose the combination of mannitol-induced BBB permeation and NF-kB decoy for enhancing the therapeutic benefits of cell therapy in stroke.

Clinical Experience With Three-Factor Prothrombin Complex Concentrate to Reverse Warfarin Anticoagulation in Intracranial Hemorrhage

Background and Purpose—

The effectiveness of prothrombin complex concentrate (PCC) products available in the United States that contain low levels of factor VII (3-factor PCC) has not been tested. The purpose of this study was to review our experience with 3-factor PCC (Profilnine) in the setting of warfarin-associated intracranial hemorrhage (wICH).

Methods—

In November 2007, we implemented a protocol for reversal of anticoagulation in wICH using Profilnine. Additional treatment with fresh-frozen plasma was at the discretion of the treating physician. Medical records of all patients receiving PCC for wICH between November 1, 2007, and December 7, 2011 were reviewed. Correction of the international normalized rate (INR) was defined as an INR <1.4.

Results—

Seventy wICH patients were treated with Profilnine, including 46 (66%) with intraparenchymal hemorrhage, 22 (31%) with subdural hemorrhage, and 2 (3%) with subarachnoid hemorrhage. Mean INR was reduced from 3.36 to 1.96, and in 44 (62.9%) patients the INR corrected to <1.4. Baseline INR ≥3.0 decreased the likelihood of INR correction. Concomitant administration of fresh-frozen plasma (mean, 2.6 U) did not increase the likelihood of INR correction. Seven (10%) patients had serious adverse events during their hospital course, including 2 sudden deaths from suspected pulmonary embolism.

Conclusions—

Reversal of coagulopathy in wICH with Profilnine was incomplete and associated with serious adverse events. In the absence of available 4-factor PCC, options for urgent reversal of anticoagulation in wICH remain limited.

Remote ischemic perconditioning is effective alone and in combination with intravenous tissue-type plasminogen activator in murine model of embolic stroke

BACKGROUND AND PURPOSE

Remote ischemic conditioning is cardioprotective in myocardial infarction and neuroprotective in mechanical occlusion models of stroke. However, there is no report on its therapeutic potential in a physiologically relevant embolic stroke model (embolic middle cerebral artery occlusion) in combination with intravenous tissue-type plasminogen activator (tPA).

METHODS

We tested remote ischemic perconditioning therapy (RIPerC) at 2 hours after embolic middle cerebral artery occlusion in the mouse with and without intravenous tPA at 4 hours. We assessed cerebral blood flow up to 6 hours, neurological deficits, injury size, and phosphorylation of Akt (Serine(473)) as a prosurvival signal in the ischemic hemisphere at 48 hours poststroke.

RESULTS

RIPerC therapy alone improved the cerebral blood flow and neurological outcomes. tPA alone at 4 hours did not significantly improve the neurological outcome even after successful thrombolysis. Individual treatments with RIPerC and intravenous tPA reduced the infarct size (25.7% and 23.8%, respectively). Combination therapy of RIPerC and tPA resulted in additive effects in further improving the neurological outcome and reducing the infarct size (50%). All the therapeutic treatments upregulated phosphorylation of Akt in the ischemic hemisphere.

CONCLUSIONS

RIPerC is effective alone after embolic middle cerebral artery occlusion and has additive effects in combination with intravenous tPA. RIPerC may be a simple, safe, and inexpensive combination therapy with intravenous tPA.

Using the Neisseria gonorrhoeae multiantigen sequence-typing method to assess strain diversity and antibiotic resistance in San Francisco, California

Urogenital Neisseria gonorrhoeae isolates (266) collected in San Francisco, CA, in 2009 were analyzed for antimicrobial susceptibility and were subsequently genotyped by N. gonorrhoeae multiantigen sequence typing (NG-MAST). Isolates of identical or closely related sequence types were found to possess highly similar phenotypes with regard to drug susceptibility. Isolates containing decreased susceptibility to oral cephalosporins were detected in 2009 and were found to contain the mosaic penA allele (XXXIV) found previously to be associated with decreased susceptibility to cephalosporins. A better understanding of the relationships between phenotypic and genotypic markers for antimicrobial resistance may be helpful to the development of effective surveillance systems for drug-resistant N. gonorrhoeae.

Repurposing an old drug to improve the use and safety of tissue plasminogen activator for acute ischemic stroke: minocycline

Tissue plasminogen activator (tPA) is the only drug approved by the United States Food and Drug Administration for treatment of acute ischemic stroke. Because the drug must be used soon after symptom onset and is associated with intracerebral hemorrhage, tPA remains underutilized. Research has therefore focused on identifying other drugs that can be used concomitantly with tPA to improve the odds of a favorable recovery and to reduce the risk of intracerebral hemorrhage. Minocycline is a broad-spectrum antibiotic that has been found to be a neuroprotective agent in preclinical ischemic stroke models. Minocycline inhibits matrix metalloproteinase-9, a biomarker for intracerebral hemorrhage associated with tPA use. Minocycline is also an antiinflammatory agent and inhibits poly(ADP-ribose) polymerase-1. Minocycline has been safe and well tolerated in clinical trials. Additional safety and efficacy data are needed, and a phase III trial of minocycline with tPA in patients experiencing acute ischemic stroke is planned.