Publications by authors named "Heena Olalde"

Trillions of microbes such as bacteria, fungi, and viruses exist in the healthy human gut microbiome. Although gut bacterial dysbiosis has been extensively studied in multiple sclerosis (MS), the significance of the fungal microbiome (mycobiome) is an understudied and neglected part of the intestinal microbiome in MS. The aim of this study was to characterize the gut mycobiome of patients with relapsing-remitting multiple sclerosis (RRMS), compare it to healthy controls, and examine its association with changes in the bacterial microbiome.

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There is a critical need for cerebro-protective interventions to improve the suboptimal outcomes of patients with ischemic stroke who have been treated with reperfusion strategies. We found that nuclear pyruvate kinase muscle 2 (PKM2), a modulator of systemic inflammation, was upregulated in neutrophils after the onset of ischemic stroke in both humans and mice. Therefore, we determined the role of PKM2 in stroke pathogenesis by using murine models with preexisting comorbidities.

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Background And Purpose: High-resolution vessel wall imaging (HR-VWI) is a powerful tool in diagnosing intracranial vasculopathies not detected on routine imaging. We hypothesized that 7T HR-VWI may detect the presence of atherosclerotic plaques in patients with intracranial atherosclerosis disease initially misdiagnosed as cryptogenic strokes.

Methods: Patients diagnosed as cryptogenic stroke but suspected of having an intracranial arteriopathy by routine imaging were prospectively imaged with HR-VWI.

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Multiple GWAS studies have shown that the SNP rs2281808 TT variant, present within the SIRPG gene, is associated with autoimmune diseases, such as type 1 diabetes. However, the role of SIRPγ in human T-cells is not known, neither is the functional significance of TT variant. Here we investigated SIRPG genotypes and their effects on the fate and function of human T-cells.

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Background And Purpose: Intravenous alteplase (rt-PA) increases the risk of hemorrhagic transformation of acute ischemic stroke. The objective of our study was to evaluate clinical, laboratory, and imaging predictors on forecasting the risk of hemorrhagic transformation following treatment with rt-PA. We also evaluated the factors associated with cerebral microbleeds that increase the risk of hemorrhagic transformation.

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Background: Patients often suffer a stroke at a significant distance from a center capable of delivering endovascular therapy, thus requiring rapid transport by helicopter emergency medical services while receiving a recombinant tissue plasminogen activator infusion that was initiated locally. But little is known about how a helicopter flight may impact the safety and efficacy of recombinant tissue plasminogen activator-induced reperfusion and patient outcomes.

Aim: To establish a new animal method to address with fidelity the safety and overall effect of helicopter emergency medical services during thrombolysis.

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Background And Purpose: Microhemorrhages on gradient-echo T2*-weighted MRI sequences are often found in patients with cerebrovascular disease and are related to intracerebral hemorrhage. Because statin therapy is associated with increased risk of intracerebral hemorrhage, we investigated whether statin use was also associated with microhemorrhages in patients with acute ischemic stroke or transient ischemic attack.

Methods: We performed a retrospective analysis on prospectively collected data from a stroke registry containing patients with acute ischemic stroke or transient ischemic attack.

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Acute stroke trials are becoming increasingly multinational. Working toward a shared ethical standard for acute stroke research necessitates evaluating the degree of consensus among international researchers. We surveyed all 275 coinvestigators and coordinators who participated in the AbESTT II study (evaluating abciximab vs placebo) about their experience with their local institutional review board (IRB) or equivalent, as well as, about their personal beliefs regarding the ethical aspects of acute stroke trials.

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Background And Purpose: Methods to increase recruitment into acute stroke trials are needed. The purposes of this study were to evaluate the safety and acceptability of initiating acute stroke trials during early helicopter evacuation and to test an intervention to facilitate informed consent.

Methods: A randomized, controlled trial was done with patients with acute stroke who were transferred by helicopter to the University of Iowa Hospitals and Clinics from February 2007 to January 2008.

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