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Staff, Nathan P

0000-0001-6760-3859

Mayo Clinic

Department of Neurology, Mayo Clinic, Rochester, MN.

Citations 61

Clinical Course of Oxaliplatin-Induced Neuropathy: Results From the Randomized Phase III Trial N08CB (Alliance)

Journal of Clinical Oncology | August 17, 2015 | Volume: 33 | Issue: 30 | Pages: 3416-3422

10.1200/jco.2014.58.8533 | PMID 26282635

Purpose Given that the clinical course of oxaliplatin-induced neuropathy is not well defined, the current study was performed to better understand clinical parameters associated with its presentation. Methods Acute and chronic neuropathy was evaluated in patients receiving adjuvant FOLFOX (fluorouracil, leucovorin, and oxaliplatin) on study N08CB (North Central Cancer Treatment Group, Alliance). Acute neuropathy was assessed by having patients complete daily questionnaires for 6 days with each cycle of FOLFOX. Before each dose of FOLFOX and as long as 18 months after chemotherapy cessation, chronic neurotoxicity was assessed with use of the 20-item, European Organisation for Research and Treatment of Cancer quality-of-life questionnaire for patients with chemotherapy-induced peripheral neuropathy. Results Three hundred eight (89%) of the 346 patients had at least one symptom of acute neuropathy with the first cycle of FOLFOX; these symptoms included sensitivity to touching cold items (71%), sensitivity to swallowing cold items (71%), throat discomfort (63%), or muscle cramps (42%). Acute symptoms peaked at day 3 and improved, although they did not always resolve completely between treatments. These symptoms were about twice as severe in cycles 2 through 12 as they were in cycle 1. For chronic neurotoxicity, tingling was the most severe symptom, followed by numbness and then pain. During chemotherapy, symptoms in the hands were more prominent than they were in the feet; by 18 months, symptoms were more severe in the feet than they were in the hands. Patients with more severe acute neuropathy during the first cycle of therapy experienced more chronic sensory neurotoxicity (P < .0001). Conclusion Acute oxaliplatin-induced neuropathy symptoms do not always completely resolve between treatment cycles and are only half as severe on the first cycle as compared with subsequent cycles. There is a correlation between the severities of acute and chronic neuropathies.
Neuropathies after surgery: Anatomical considerations of pathologic mechanisms

Clinical Anatomy | May 14, 2015 | Volume: 28 | Issue: 5 | Pages: 678-682

10.1002/ca.22564 | PMID 25974415

Positioning‐related injuries caused during surgery under anesthesia are most likely multifactorial. Pathologic mechanical forces alone (overstretching and/or ischemia from direct compression) may not fully explain postsurgical neuropathy with recent evidence implicating patient‐specific factors or perioperative inflammatory responses spatially and even temporally divorced from the anatomical region of injury. The aim of this introductory article is to provide an overview of anatomic considerations of these mechanical forces on soft and nervous tissues along with factors that may compound compression or stretch injury. Three subsequent articles will address specific positioning‐related anatomic considerations of the (1) upper extremities, (2) lower extremities, and (3) central nervous system and soft tissues. Clin. Anat. 28:678–682, 2015. © 2015 Wiley Periodicals, Inc.
Impairments and comorbidities of polyneuropathy revealed by population-based analyses

Neurology | April 2, 2015 | Volume: 84 | Issue: 16 | Pages: 1644-1651

10.1212/wnl.0000000000001492 | PMID 25832668

Magnetic resonance imaging abnormalities of peripheral nerve and muscle are common in amyotrophic lateral sclerosis and share features with multifocal motor neuropathy

Muscle & Nerve | March 3, 2015 | Volume: 52 | Issue: 1 | Pages: 137-139

10.1002/mus.24630 | PMID 25736373

A safety study on intrathecal delivery of autologous mesenchymal stromal cells in rabbits directly supporting Phase I human trials

Transfusion | November 21, 2014 | Volume: 55 | Issue: 5 | Pages: 1013-1020

10.1111/trf.12938 | PMID 25413276

BackgroundThere are no effective treatments that slow the progression of neurodegenerative diseases. A major challenge of treatment in neurodegenerative diseases is appropriate delivery of pharmaceuticals into the cerebrospinal fluid (CSF) of affected individuals. Mesenchymal stromal cells (MSCs—either naïve or modified) are a promising therapy in neurodegenerative diseases and may be delivered directly into the CSF where they can reside for months. In this preclinical study, we evaluated the safety of intrathecal autologous MSCs in a rabbit model.Study Design and MethodsAutologous adipose‐derived MSCs (or artificial CSF) were delivered intrathecally, either with single or with repeated injections into the foramen magnum of healthy rabbits and monitored for 4 and 12 weeks, respectively.ResultsRabbits tolerated injections well and no definitive MSC‐related side effects were observed apart from three rabbits that had delayed death secondary to traumatic foramen magnum puncture. Functional assessments and body weights were equivalent between groups. Gross pathology and histology did not reveal any abnormalities or tumor growth. Complete blood count data were normal and there were no differences in CSF interleukin‐6 levels in all groups tested.ConclusionOur data suggest that intrathecal delivery of autologous MSCs is safe in a rabbit model. Data from this study have supported two successful investigational new drug applications to the Food and Drug Administration, resulting in the initiation of two clinical trials using autologous MSCs in amyotrophic lateral sclerosis and multiple system atrophy.
Autonomic system and amyotrophic lateral sclerosis

Muscle & Nerve | September 11, 2014 | Volume: 51 | Issue: 5 | Pages: 676-679

10.1002/mus.24457 | PMID 25211238

ABSTRACTIntroduction: The aim of this study is to characterize autonomic impairment in motor neuron disease. Methods: Neurological evaluations and autonomic testing were analyzed retrospectively in 132 patients: 86 classic amyotrophic lateral sclerosis (ALS), 36 lower motor neuron (LMN), and 10 upper motor neuron (UMN) predominant disease. Results: One‐third of patients were symptomatic; urinary urgency and constipation were the most frequent symptoms. Increased Composite Autonomic Severity Score (CASS) was present in 75% with mild impairment (CASS 1–3) in 85% and moderate (CASS 4–7) in 15%. The frequencies of testing abnormalities were: sudomotor 46%, cardiovagal 50%, and adrenergic 14%. The UMN group had significantly higher median CASS scores than the classic ALS (P = 0.021) and LMN group (P = 0.018). Conclusions: We found predominantly mild autonomic impairment in ALS patients, with mostly cardiovagal and sudomotor involvement. Moderate autonomic failure occurred in 1 of 7 patients, especially those with an UMN presentation. Patients with selective corticospinal tract involvement may have more impairment of autonomic pathways. Muscle Nerve 51:676–679, 2015
Breaking Down Translation Barriers: Investigator’s Perspective

Science Translational Medicine | September 4, 2014 | Volume: 6 | Issue: 252 | Pages: No page available

10.1126/scitranslmed.3008252 | PMID 25186172

Biomedical scientists can exploit initiatives from U.S. federal regulatory and funding agencies aimed at accelerating clinical translation.
Chronic meralgia paresthetica and neurectomy

Neurology | March 29, 2014 | Volume: 82 | Issue: 17 | Pages: 1551-1555

10.1212/wnl.0000000000000367 | PMID 24682967

Postsurgical Inflammatory Neuropathy Should Be Considered in the Differential Diagnosis of Diaphragm Paralysis after Surgery

Anesthesiology | March 19, 2014 | Volume: 120 | Issue: 4 | Pages: 1057-1057

10.1097/aln.0000000000000130 | PMID 24694857

Assessing Decreased Sensation and Increased Sensory Phenomena in Diabetic Polyneuropathies

Diabetes | October 24, 2013 | Volume: 62 | Issue: 11 | Pages: 3677-3686

10.2337/db13-0352 | PMID 24158999

Loss of sensation and increased sensory phenomena are major expressions of varieties of diabetic polyneuropathies needing improved assessments for clinical and research purposes. We provide a neurobiological explanation for the apparent paradox between decreased sensation and increased sensory phenomena. Strongly endorsed is the use of the 10-g monofilaments for screening of feet to detect sensation loss, with the goal of improving diabetic management and prevention of foot ulcers and neurogenic arthropathy. We describe improved methods to assess for the kind, severity, and distribution of both large- and small-fiber sensory loss and which approaches and techniques may be useful for conducting therapeutic trials. The abnormality of attributes of nerve conduction may be used to validate the dysfunction of large sensory fibers. The abnormality of epidermal nerve fibers/1 mm may be used as a surrogate measure of small-fiber sensory loss but appear not to correlate closely with severity of pain. Increased sensory phenomena are recognized by the characteristic words patients use to describe them and by the severity and persistence of these symptoms. Tests of tactile and thermal hyperalgesia are additional markers of neural hyperactivity that are useful for diagnosis and disease management.