UW Neurological Surgery Recent PubMed Publications

A Randomized Controlled Trial of a Citywide Emergency Department Care-Coordination Program to Reduce Prescription Opioid-Related Visits: An Economic Evaluation.

J Emerg Med. 2017 Aug;53(2):186-194

Authors: Murphy SM, Howell D, McPherson S, Grohs R, Roll J, Neven D

Abstract
BACKGROUND: Care provided in the emergency department (ED) can cost up to five times as much as care received for comparable diagnoses in alternative settings. Small groups of patients, many of whom suffer from an opioid use disorder, often account for a large proportion of total ED visits. We recently conducted, and demonstrated the effectiveness of, the first randomized controlled trial of a citywide ED care-coordination program intending to reduce prescription-opioid-related ED visits. All EDs in the metropolitan study area were connected to a Web-based information exchange system.
OBJECTIVE: The objective of this article was to perform an economic evaluation of the 12-month trial from a third-party-payer perspective.
METHODS: We modeled the person-period monthly for the 12-month observation period, and estimated total treatment costs and return on investment (ROI) with regard to cost offsets, over time, for all visits where the patient was admitted to and discharged from the ED.
RESULTS: By the end of month 4, the mean cumulative cost differential was significantly lower for intervention relative to treatment-as-usual participants (-$1370; p = 0.03); this figure climbed to -$3200 (p = 0.02) by the end of month 12. The ROI trended upward throughout the observation period, but failed to reach statistical significance by the end of month 12 (ROI = 3.39, p = 0.07).
CONCLUSION: The intervention produced significant cost offsets by the end of month 4, which continued to accumulate throughout the trial; however, ROI was not significant. Because the per-patient administrative costs of the program are incurred at the time of enrollment, our results highlight the importance of future studies that are able to follow participants for a period beyond 12 months to more accurately estimate the program's ROI.

PMID: 28410960 [PubMed - indexed for MEDLINE]

A Phase Ib Dose-Escalation Study of the Safety, Tolerability, and Pharmacokinetics of Cobimetinib and Duligotuzumab in Patients with Previously Treated Locally Advanced or Metastatic Cancers with Mutant KRAS.

Oncologist. 2017 Sep;22(9):1024-e89

Authors: Lieu CH, Hidalgo M, Berlin JD, Ko AH, Cervantes A, LoRusso P, Gerber DE, Eder JP, Eckhardt SG, Kapp AV, Tsuhako A, McCall B, Pirzkall A, Uyei A, Tabernero J

Abstract
LESSONS LEARNED: Cobimetinib and duligotuzumab were well tolerated as single agents and in combination with other agents.The cobimetinib and duligotuzumab combination was associated with increased toxicity, most notably gastrointestinal, and limited efficacy in the patient population tested.
BACKGROUND: KRAS-mutant tumors possess abnormal mitogen-activated protein kinases (MAPK) pathway signaling, leading to dysregulated cell proliferation. Cobimetinib blocks MAPK signaling. The dual-action antibody duligotuzumab (MEHD7945A) inhibits ligand binding to both epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 3 (HER3). Blockade of EGFR/HER3 and inhibition of mitogen-activated protein kinase (MEK) in KRAS-mutant tumors may provide additive benefit.
METHODS: Patients with KRAS-mutant solid tumors were eligible for this phase Ib dose-escalation study with a planned expansion phase. Duligotuzumab was given intravenously (IV) at 1,100 mg every 2 weeks (q2w), while cobimetinib was given orally in a standard 3 + 3 design to identify the recommended phase II dose (RP2D). The primary objective was to evaluate the safety and tolerability of this combination.
RESULTS: Twenty-three patients were enrolled. Dose-limiting toxicities (DLTs) included grade 4 hypokalemia and grade 3 mucosal inflammation, asthenia, and dermatitis acneiform. Seventy percent of patients experienced grade 3 or worse adverse events (AEs). Five (22%) and 12 (52%) patients missed at least 1 dose of duligotuzumab and cobimetinib, respectively, and 9 (39%) patients required a cobimetinib dose reduction. Three (13%) patients discontinued due to an AE. Best response was limited to 9 patients with stable disease and 13 patients with progressive disease.
CONCLUSION: Given the limited tolerability and efficacy of this combination, the study did not proceed to expansion stage and closed for enrollment.

PMID: 28592615 [PubMed - indexed for MEDLINE]

Rapid Intraoperative in Situ Synthetic Cranioplasty.

World Neurosurg. 2018 Apr;112:161-165

Authors: Young CC, Hanak BW, Patel AP, Sekhar LN

Abstract
Craniectomy is a frequently performed neurosurgical procedure, and coverage of the cranial defect is necessary for protection of the underlying brain, cosmesis, and patient satisfaction. We report a new technique for intraoperative in situ synthetic cranioplasty that provides one-step resection of skull osteomas and reconstruction of cranial defects. Strategies of intraoperative cranioplasty are reviewed. A 48-year-old man who presented with a suspected benign osteoma over his forehead was offered surgical excision and primary cranioplasty in a one-step procedure using hydroxyapatite bone cement, a dural prosthetic, and a resorbable plate. Following craniectomy around the lesion, there was evidence of dural and bone involvement. The craniectomy was enlarged, and the involved dura was resected. SYNTHECEL dura repair was used to repair the dural defect and at the same time fashioned to form a receptacle for the cranioplasty by fixation of the dural substrate to the cut vertical bone edges. DirectInject hydroxyapatite bone cement was used to fill the receptacle and contoured to the curvature of the adjacent skull. A Delta resorbable plate was then placed over the bone cement and fixed to the skull. This technique provided a satisfactory cosmetic outcome following craniectomy for benign skull tumor excision. When possible, one-step surgery with primary cranioplasty should be considered.

PMID: 29409926 [PubMed - indexed for MEDLINE]

Atypical Presentation of Giant Aneurysm in Pediatric Patient with Duane Syndrome.

World Neurosurg. 2018 Aug;116:25-28

Authors: Kuo CH, McGrath LB, Carnevale JA, Marupudi NI, Ojemann JG, Ellenbogen RG, Wang AC

Abstract
BACKGROUND: Duane syndrome is a congenital eye movement disorder characterized by congenital malformation of the abducens nucleus. Thrombogenic conditions during development may lead to vascular anomalies in Duane syndrome; however, the presence of a giant aneurysm in this patient population is a rarely documented phenomenon.
CASE DESCRIPTION: We reported a case of a large cerebral aneurysm in a pediatric patient with Duane syndrome and performed a review of the literature to identify other potential cases and associations. The pathophysiologic hallmarks of Duane syndrome that lead to alterations in the fetal cerebral vasculature and that may form the basis for a potential mechanism for aneurysm formation were reviewed in this study. The patient was an 11-year-old female with Duane syndrome who presented with seizures. Computed tomography and magnetic resonance imaging demonstrated a large, heterogeneously enhancing right temporal mass. Intraoperatively, the mass was revealed to be a partially thrombosed giant middle cerebral artery aneurysm. After surgery, the patient had an uneventful postoperative course without residual aneurysm presented on postoperative angiogram. No clinical or radiographic appearance of recurrent aneurysm was evident at her 6-month follow-up.
CONCLUSIONS: The pathophysiology of vascular anomalies with Duane syndrome may be related to thrombogenic conditions during development leading to alterations in cerebral fetal vasculature. Strong consideration for vascular anomaly should be given when evaluating cerebral masses in patients with Duane syndrome.

PMID: 29777883 [PubMed - indexed for MEDLINE]

Differential effects of perinatal exposure to antidepressants on learning and memory, acoustic startle, anxiety, and open-field activity in Sprague-Dawley rats.

Int J Dev Neurosci. 2017 Oct;61:92-111

Authors: Sprowles JLN, Hufgard JR, Gutierrez A, Bailey RA, Jablonski SA, Williams MT, Vorhees CV

Abstract
Most antidepressants inhibit monoamine reuptake. Selective serotonin (5-HT) reuptake inhibitors (SSRIs) act on the 5-HT transporter (SERT) whereas norepinephrine-dopamine reuptake inhibitors (NDRIs) act on the norepinephrine and dopamine transporters. Epidemiological reports link SSRI use during pregnancy to an increased prevalence of autism spectrum disorder (ASD). We previously showed that perinatal exposure to the SSRI citalopram (CIT) results in rodent offspring that exhibit a number of behaviors consistent with an ASD-like phenotype. The present study examined the effect of perinatal exposure to CIT (at a lower dose), another SSRI, fluoxetine (FLX), and an NDRI, bupropion (BUP). Gravid Sprague-Dawley rats were subcutaneously injected twice per day (6h apart) with 5mg/kg CIT, 5mg/kg FLX, 15mg/kg BUP, or saline (SAL) from embryonic day (E) 6-21, and directly to the pups from postnatal day (P) 1-20. As adults, one male/female from each litter was given one of a series of tests. Both SSRI-exposed groups showed spatial learning deficits in Morris and radial water mazes, increased marble burying, increased acoustic startle, hypoactivity, and attenuated activity to the stimulating effect of the NMDA-R antagonist MK-801. The BUP-exposed group showed a reduction in elevated zero-maze quadrant entries and increased stimulated open-field activity following (+)-amphetamine challenge. These results reinforce concern about the use of antidepressants during pregnancy and highlight how the two classes of drugs produce different constellations of effects with more effects associated with the SSRIs. Further investigation into how antidepressants alter brain development leading to enduring adverse neurobehavioral effects is warranted.

PMID: 28655626 [PubMed - indexed for MEDLINE]

The Outcome of Severe Traumatic Brain Injury in Latin America.

World Neurosurg. 2018 Mar;111:e82-e90

Authors: Bonow RH, Barber J, Temkin NR, Videtta W, Rondina C, Petroni G, Lujan S, Alanis V, La Fuente G, Lavadenz A, Merida R, Jibaja M, Gonzáles L, Falcao A, Romero R, Dikmen S, Pridgeon J, Chesnut RM, Global Neurotrauma Research Group

Abstract
BACKGROUND: Traumatic brain injury (TBI) disproportionately affects lower- and middle-income countries (LMIC). The factors influencing outcomes in LMIC have not been examined as rigorously as in higher-income countries.
METHODS: This study was conducted to examine clinical and demographic factors influencing TBI outcomes in Latin American LMIC. Data were prospectively collected during a randomized trial of intracranial pressure monitoring in severe TBI and a companion observational study. Participants were aged ≥13 years and admitted to study hospitals with Glasgow Coma Scale score ≤8. The primary outcome was Glasgow Outcome Scale, Extended (GOS-E) score at 6 months. Predictors were analyzed using a multivariable proportional odds model created by forward stepwise selection.
RESULTS: A total of 550 patients were identified. Six-month outcomes were available for 88%, of whom 37% had died and 44% had achieved a GOS-E score of 5-8. In multivariable proportional odds modeling, higher Glasgow Coma Scale motor score (odds ratio [OR], 1.41 per point; 95% confidence interval [CI], 1.23-1.61) and epidural hematoma (OR, 1.83; 95% CI, 1.17-2.86) were significant predictors of higher GOS-E score, whereas advanced age (OR, 0.65 per 10 years; 95% CI, 0.57-0.73) and cisternal effacement (P < 0.001) were associated with lower GOS-E score. Study site (P < 0.001) and race (P = 0.004) significantly predicted outcome, outweighing clinical variables such as hypotension and pupillary examination.
CONCLUSIONS: Mortality from severe TBI is high in Latin American LMIC, although the rate of favorable recovery is similar to that of high-income countries. Demographic factors such as race and study site played an outsized role in predicting outcome; further research is required to understand these associations.

PMID: 29229352 [PubMed - indexed for MEDLINE]

What is the current role of bypass surgery in the management of cerebral aneurysms?

Neurol India. 2018 May-Jun;66(3):661-663

Authors: Sekhar LN, Cheng CY, Da Silva HB, Qazi Z

PMID: 29766916 [PubMed - indexed for MEDLINE]

GRP78 haploinsufficiency suppresses acinar-to-ductal metaplasia, signaling, and mutant Kras-driven pancreatic tumorigenesis in mice.

Proc Natl Acad Sci U S A. 2017 05 16;114(20):E4020-E4029

Authors: Shen J, Ha DP, Zhu G, Rangel DF, Kobielak A, Gill PS, Groshen S, Dubeau L, Lee AS

Abstract
Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal disease in critical need of new therapeutic strategies. Here, we report that the stress-inducible 78-kDa glucose-regulated protein (GRP78/HSPA5), a key regulator of endoplasmic reticulum homeostasis and PI3K/AKT signaling, is overexpressed in the acini and PDAC of Pdx1-Cre;KrasG12D/+;p53f/+ (PKC) mice as early as 2 mo, suggesting that GRP78 could exert a protective effect on acinar cells under stress, as during PDAC development. The PKC pancreata bearing wild-type Grp78 showed detectable PDAC by 3 mo and rapid subsequent tumor growth. In contrast, the PKC pancreata bearing a Grp78f/+ allele (PKC78f/+ mice) expressing about 50% of GRP78 maintained normal sizes during the early months, with reduced proliferation and suppression of AKT, S6, ERK, and STAT3 activation. Acinar-to-ductal metaplasia (ADM) has been identified as a key tumor initiation mechanism of PDAC. Compared with PKC, the PKC78f/+ pancreata showed substantial reduction of ADM as well as pancreatic intraepithelial neoplasia-1 (PanIN-1), PanIN-2, and PanIN-3 and delayed onset of PDAC. ADM in response to transforming growth factor α was also suppressed in ex vivo cultures of acinar cell clusters isolated from mouse pancreas bearing targeted heterozygous knockout of Grp78 (c78f/+ ) and subjected to 3D culture in collagen. We further discovered that GRP78 haploinsufficiency in both the PKC78f/+ and c78f/+ pancreata leads to reduction of epidermal growth factor receptor, which is critical for ADM initiation. Collectively, our studies establish a role for GRP78 in ADM and PDAC development.

PMID: 28461470 [PubMed - indexed for MEDLINE]

Nanoparticles That Reshape the Tumor Milieu Create a Therapeutic Window for Effective T-cell Therapy in Solid Malignancies.

Cancer Res. 2018 07 01;78(13):3718-3730

Authors: Zhang F, Stephan SB, Ene CI, Smith TT, Holland EC, Stephan MT

Abstract
A major obstacle to the success rate of chimeric antigen receptor (CAR-) T-cell therapy against solid tumors is the microenvironment antagonistic to T cells that solid tumors create. Conventional checkpoint blockade can silence lymphocyte antisurvival pathways activated by tumors, but because they are systemic, these treatments disrupt immune homeostasis and induce autoimmune side effects. Thus, new technologies are required to remodel the tumor milieu without causing systemic toxicities. Here, we demonstrate that targeted nanocarriers that deliver a combination of immune-modulatory agents can remove protumor cell populations and simultaneously stimulate antitumor effector cells. We administered repeated infusions of lipid nanoparticles coated with the tumor-targeting peptide iRGD and loaded with a combination of a PI3K inhibitor to inhibit immune-suppressive tumor cells and an α-GalCer agonist of therapeutic T cells to synergistically sway the tumor microenvironment of solid tumors from suppressive to stimulatory. This treatment created a therapeutic window of 2 weeks, enabling tumor-specific CAR-T cells to home to the lesion, undergo robust expansion, and trigger tumor regression. CAR-T cells administered outside this therapeutic window had no curative effect. The lipid nanoparticles we used are easy to manufacture in substantial amounts, and we demonstrate that repeated infusions of them are safe. Our technology may therefore provide a practical and low-cost strategy to potentiate many cancer immunotherapies used to treat solid tumors, including T-cell therapy, vaccines, and BITE platforms.Significance: A new nanotechnology approach can promote T-cell therapy for solid tumors. Cancer Res; 78(13); 3718-30. ©2018 AACR.

PMID: 29760047 [PubMed - indexed for MEDLINE]

Successful treatment of direct carotid-cavernous fistula in a patient with Ehlers-Danlos syndrome type IV without arterial puncture: the transvenous triple-overlay embolization (TAILOREd) technique.

BMJ Case Rep. 2017 Aug 18;2017:

Authors: Huynh TJ, Morton RP, Levitt MR, Ghodke BV, Wink O, Hallam DK

Abstract
We report successful transvenous treatment of direct carotid-cavernous fistula in a patient with Ehlers-Danlos syndrome type IV using a novel triple-overlay embolization (TAILOREd) technique without the need for arterial puncture, which is known to be highly risky in this patient group. The TAILOREd technique allowed for successful treatment using preoperative MR angiography as a three-dimensional overlay roadmap combined with cone beam CT and live fluoroscopy, precluding the need for an arterial puncture.

PMID: 28824011 [PubMed - indexed for MEDLINE]

Neural Cotransmission in Spinal Circuits Governing Locomotion.

Trends Neurosci. 2018 May 07;:

Authors: Svensson E, Williams MJ, Schiöth HB

Abstract
Many neuronal circuits contain, or are influenced by, colocalized neurotransmitters, which are suggested to fine-tune circuit function. Much of our knowledge about cotransmission derives from studies in non-mammalian model systems, although a growing number of studies have provided insights into the physiological role of cotransmission in more complex mammalian circuits, including the spinal cord. Here we discuss the current picture of colocalized neurotransmitters in spinal circuits of non-mammalian and mammalian systems, as well as the progression towards understanding of their functional roles. We delineate both evolutionarily conserved and divergent aspects of spinal cotransmission and highlight open questions in the area.

PMID: 29747855 [PubMed - as supplied by publisher]

MicroRNA 21a-5p overexpression impacts mediators of extracellular matrix formation in uterine leiomyoma.

Reprod Biol Endocrinol. 2018 May 11;16(1):46

Authors: Cardozo ER, Foster R, Karmon AE, Lee AE, Gatune LW, Rueda BR, Styer AK

Abstract
BACKGROUND: MicroRNAs (MiR) may promote fibroid development via altered expression of genes involved in cell proliferation and ECM formation, and evidence supports aberrant expression of MicroRNA (MiR) 21a-5p in fibroids. The purpose of this study was to investigate the functional significance of MiR 21a-5p overexpression in the pathobiology of leiomyomata (fibroids).
METHODS: A basic science experimental design using immortalized fibroid and myometrial cell lines derived from patient-matched specimens was used. Stable overexpression of MiR-21a-5p in an immortalized fibroid and patient matched myometrial cell line was achieved through lentiviral vector infection. Main outcome measures were MiR-21-5p overexpression, target gene and protein expression, collagen (COL1A1) production, cell proliferation, cell migration, and cell cycle stages of fibroid and myometrial immortalized cell lines.
RESULTS: MiR-21a-5p was overexpressed to similar levels in fibroid and myometrial cell lines after lentiviral infection. Increased expression of miR-21 resulted in increased gene and protein expression of TGF-β3 in both fibroid and myometrial cells. Changes in expression of the ECM genes Fibronectin, Collagen 1A1, CTGF, Versican and DPT were seen in both fibroid and myometrial cells. Changes were also seen in Matrix Metalloproteinase (MMP) related genes including MMP 2, MMP 9, MMP 11 and Serpine 1 in both fibroid and myometrial cells. MiR-21 upregulation resulted in increased proliferation and migration in fibroid cells compared to myometrial cells.
CONCLUSIONS: MiR-21a-5p overexpression results in changes in the expression of ECM mediators in both fibroid and myometrial cells, and increased cell proliferation in fibroid cells. These finding suggest a potential functional role of MiR-21a-5p in the development of uterine fibroids and warrant further investigation.

PMID: 29747655 [PubMed - indexed for MEDLINE]

In Reply.

J Oral Maxillofac Surg. 2018 08;76(8):1601-1602

Authors: Brandner JS, Rawal YB, Kim LJ, Dillon JK

PMID: 29746841 [PubMed - indexed for MEDLINE]

Amantadine Did Not Positively Impact Cognition in Chronic Traumatic Brain Injury: A Multi-Site, Randomized, Controlled Trial.

J Neurotrauma. 2018 10 01;35(19):2298-2305

Authors: Hammond FM, Sherer M, Malec JF, Zafonte RD, Dikmen S, Bogner J, Bell KR, Barber J, Temkin N

Abstract
Despite limited evidence to support the use of amantadine to enhance cognitive function after traumatic brain injury (TBI), the clinical use for this purpose is highly prevalent and is often based on inferred belief systems. The aim of this study was to assess effect of amantadine on cognition among individuals with a history of TBI and behavioral disturbance using a parallel-group, randomized, double-blind, placebo-controlled trial of amantadine 100 mg twice-daily versus placebo for 60 days. Included in the study were 119 individuals with two or more neuropsychological measures greater than 1 standard deviation below normative means from a larger study of 168 individuals with chronic TBI (>6 months post-injury) and irritability. Cognitive function was measured at treatment days 0, 28, and 60 with a battery of neuropsychological tests. Composite indices were generated: General Cognitive Index (included all measures), a Learning Memory Index (learning/memory measures), and Attention/Processing Speed Index (attention and executive function measures). Repeated-measures analysis of variance revealed statistically significant between-group differences favoring the placebo group at day 28 for General Cognitive Index (p = 0.002) and Learning Memory Index (p = 0.001), but not Attention/Processing Speed Index (p = 0.25), whereas no statistically significant between-group differences were found at day 60. There were no statistically significant between-group differences on adverse events. Cognitive function in individuals with chronic TBI is not improved by amantadine 100 mg twice-daily. In the first 28 days of use, amantadine may impede cognitive processing. However, the effect size was small and mean scores for both groups were generally within expectations for persons with history of complicated mild-to-severe TBI, suggesting that changes observed across assessments may not have functional significance. The use of amantadine to enhance cognitive function is not supported by these findings.

PMID: 29742960 [PubMed - indexed for MEDLINE]

Advances in cellular and integrative control of oxygen homeostasis within the central nervous system.

J Physiol. 2018 08;596(15):3043-3065

Authors: Ramirez JM, Severs LJ, Ramirez SC, Agosto-Marlin IM

Abstract
Mammals must continuously regulate the levels of O2 and CO2 , which is particularly important for the brain. Failure to maintain adequate O2 /CO2 homeostasis has been associated with numerous disorders including sleep apnoea, Rett syndrome and sudden infant death syndrome. But, O2 /CO2 homeostasis poses major regulatory challenges, even in the healthy brain. Neuronal activities change in a differentiated, spatially and temporally complex manner, which is reflected in equally complex changes in O2 demand. This raises important questions: is oxygen sensing an emergent property, locally generated within all active neuronal networks, and/or the property of specialized O2 -sensitive CNS regions? Increasing evidence suggests that the regulation of the brain's redox state involves properties that are intrinsic to many networks, but that specialized regions in the brainstem orchestrate the integrated control of respiratory and cardiovascular functions. Although the levels of O2 in arterial blood and the CNS are very different, neuro-glial interactions and purinergic signalling are critical for both peripheral and CNS chemosensation. Indeed, the specificity of neuroglial interactions seems to determine the differential responses to O2 , CO2 and the changes in pH.

PMID: 29742297 [PubMed - indexed for MEDLINE]

Cardiac-Related Spinal Cord Tissue Motion at the Foramen Magnum is Increased in Patients with Type I Chiari Malformation and Decreases Postdecompression Surgery.

World Neurosurg. 2018 Aug;116:e298-e307

Authors: Lawrence BJ, Luciano M, Tew J, Ellenbogen RG, Oshinski JN, Loth F, Culley AP, Martin BA

Abstract
OBJECTIVE: Type 1 Chiari malformation (CM-I) is a craniospinal disorder historically defined by cerebellar tonsillar position greater than 3-5 mm below the foramen magnum (FM). This definition has come under question because quantitative measurements of cerebellar herniation do not always correspond with symptom severity. Researchers have proposed several additional radiographic diagnostic criteria based on dynamic motion of fluids and/or tissues. The present study objective was to determine if cardiac-related craniocaudal spinal cord tissue displacement is an accurate indicator of the presence of CM-I and if tissue displacement is altered with decompression.
METHODS: A cohort of 20 symptomatic patients underwent decompression surgery. Fifteen healthy volunteers were recruited for comparison with the CM-I group. Axial phase-contrast magnetic resonance imaging (PC-MRI) measurements were collected before and after surgery at the FM with cranial-caudal velocity encoding and 20 frames per cardiac cycle with retrospective reconstruction. Spinal cord motion (SCM) at the FM was quantified based on the peak-to-peak integral of average spinal cord velocity.
RESULTS: Tissue motion for the presurgical group was significantly greater than controls (P = 0.0009). Motion decreased after surgery (P = 0.058) with an effect size of -0.151 mm and a standard error of 0.066 mm. Postoperatively, no statistical difference from controls in bulk displacement at the FM was found (P = 0.200) after post hoc testing using the Tukey adjustment for multiple comparisons.
CONCLUSIONS: These results support SCM measurement by PC-MRI as a possible noninvasive radiographic diagnostic for CM-I. Dynamic measurement of SCM provides unique diagnostic information about CM-I alongside static quantification of tonsillar position and other intracranial morphometrics.

PMID: 29733988 [PubMed - indexed for MEDLINE]

Phytoremediation removal rates of benzene, toluene, and chlorobenzene.

Int J Phytoremediation. 2018 Jun 07;20(7):666-674

Authors: Limmer MA, Wilson J, Westenberg D, Lee A, Siegman M, Burken JG

Abstract
Phytoremediation is a sustainable remedial approach, although performance efficacy is rarely reported. In this study, we assessed a phytoremediation plot treating benzene, toluene, and chlorobenzene. A comparison of the calculated phytoremediation removal rate with estimates of onsite contaminant mass was used to forecast cleanup periods. The investigation demonstrated that substantial microbial degradation was occurring in the subsurface. Estimates of transpiration indicated that the trees planted were removing approximately 240,000 L of water per year. This large quantity of water removal implies substantial removal of contaminant due to large amounts of contaminants in the groundwater; however, these contaminants extensively sorb to the soil, resulting in large quantities of contaminant mass in the subsurface. The total estimate of subsurface contaminant mass was also complicated by the presence of non-aqueous phase liquids (NAPL), additional contaminant masses that were difficult to quantify. These uncertainties of initial contaminant mass at the site result in large uncertainty in the cleanup period, although mean estimates are on the order of decades. Collectively, the model indicates contaminant removal rates on the order of 10-2-100 kg/tree/year. The benefit of the phytoremediation system is relatively sustainable cleanup over the long periods necessary due to the presence of NAPL.

PMID: 29723051 [PubMed - indexed for MEDLINE]

Clinical Characteristics, Sex Differences, and Outcomes in Patients With Normal or Near-Normal Coronary Arteries, Non-Obstructive or Obstructive Coronary Artery Disease.

J Am Heart Assoc. 2018 05 02;7(10):

Authors: Ouellette ML, Löffler AI, Beller GA, Workman VK, Holland E, Bourque JM

Abstract
BACKGROUND: Normal or near-normal coronary arteries (NNCAs) or nonobstructive coronary artery disease (CAD) are found on invasive coronary angiography in ≈55% of patients. Some attribute this to frequent referral of low-risk patients. We sought to identify the referral indications, pretest risk, key clinical characteristics, sex, and outcomes in patients with NNCAs and nonobstructive CAD versus obstructive CAD on nonemergent invasive coronary angiography.
METHODS AND RESULTS: Over 24 months, 925 consecutive patients were classified as having NNCAs (≤20% stenosis), nonobstructive CAD (21-49% stenosis), or obstructive CAD (≥50% stenosis). Outcomes included cardiac death, nonfatal myocardial infarction, and late revasclarization. NNCAs were found in 285 patients (31.0%), nonobstructive CAD in 125 (13.5%), and obstructive CAD in 513 (55.5%). NNCAs or nonobstructive CAD was found in 40.5% with stress ischemia, 27.9% after a non-ST-elevation myocardial infarction, and in 55.5% with stable or unstable angina. More women than men (53.5% versus 37.2%; P<0.001) had NNCAs or nonobstructive CAD across all referral indications. Pretest risk was high and ICA appropriate in 75.5% and 99.2% of patients, respectively. Annual rates of cardiac death or nonfatal myocardial infarction were 1.0%, 1.1%, and 6.7%, respectively, for patients with NNCAs, nonobstructive CAD, and obstructive CAD (P<0.001). No sex differences in outcomes were observed with either NNCAs, nonobstructive CAD, or obstructive CAD (P=0.84).
CONCLUSIONS: Many (44.5%) patients undergoing nonemergent invasive coronary angiography have NNCAs or nonobstructive CAD despite high pretest risk, including ischemia and troponin elevation. Although women had more NNCAs or nonobstructive CAD, there were no differences in event rates by sex. Patients with NNCAs and nonobstructive CAD had very low event rates.

PMID: 29720503 [PubMed - indexed for MEDLINE]

The Dynamic Basis of Respiratory Rhythm Generation: One Breath at a Time.

Annu Rev Neurosci. 2018 07 08;41:475-499

Authors: Ramirez JM, Baertsch NA

Abstract
Rhythmicity is a universal timing mechanism in the brain, and the rhythmogenic mechanisms are generally dynamic. This is illustrated for the neuronal control of breathing, a behavior that occurs as a one-, two-, or three-phase rhythm. Each breath is assembled stochastically, and increasing evidence suggests that each phase can be generated independently by a dedicated excitatory microcircuit. Within each microcircuit, rhythmicity emerges through three entangled mechanisms: ( a) glutamatergic transmission, which is amplified by ( b) intrinsic bursting and opposed by ( c) concurrent inhibition. This rhythmogenic triangle is dynamically tuned by neuromodulators and other network interactions. The ability of coupled oscillators to reconfigure and recombine may allow breathing to remain robust yet plastic enough to conform to nonventilatory behaviors such as vocalization, swallowing, and coughing. Lessons learned from the respiratory network may translate to other highly dynamic and integrated rhythmic systems, if approached one breath at a time.

PMID: 29709210 [PubMed - indexed for MEDLINE]

Ischemic retinal vein occlusion: characterizing the more severe spectrum of retinal vein occlusion.

Surv Ophthalmol. 2018 Nov - Dec;63(6):816-850

Authors: Khayat M, Williams M, Lois N

Abstract
Retinal vein occlusion (RVO)-including central RVO, branch RVO, and hemicentral and hemispheric RVO-is the second most common vascular cause of visual loss, surpassed only by diabetic retinopathy. The presence and extent of retinal ischemia in RVO is associated with a worse prognosis. On this basis, most previously conducted studies considered ischemic retinal vein occlusion (iRVO) and non-iRVO as separate entities based on set thresholds of existing retinal ischemia as determined by fundus fluorescein angiography. Other diagnostic technologies have been used specifically in the differentiation of ischemic central retinal vein occlusion and nonischemic central retinal vein occlusion. To date, there is no fully accepted definition for iRVO. Some clinicians and researchers may favor establishing a clear differentiation between these forms of RVO; others may prefer not to consider iRVO as a separate entity. Whatever the case, retinal ischemia in RVO confers a higher risk of visual loss and neovascular complications; thus, it should be determined as accurately as possible in patients with this disease and be considered in clinical and experimental studies. Most recently conducted clinical trials evaluating new treatments for macular edema secondary to RVO included none or only few patients with iRVO based on previous definitions (i.e., few patients with sizeable areas of retinal ischemia were recruited in these trials), and thus it is unclear whether the results observed in recruited patients could be extrapolated to those with retinal ischemia. There has been scant research aiming at developing and/or testing treatments for retinal ischemia, as well as to prevent new vessel formation as a result of RVO. We provide a detailed review of the knowledge gathered over the years on iRVO, from controversies on its definition and diagnosis to the understanding of its epidemiology, risk factors and pathogenesis, the structural and functional effects of this disease in the eye and its complications, natural history, and outcomes after treatment. In each section, the definition of iRVO used is given so, independently of whether iRVO is considered a separate clinical entity or a more severe end of the spectrum of RVO, the information will be useful to clinicians to determine patient's risk, guide therapeutic decisions, and counsel patients and for researchers to design future studies.

PMID: 29705175 [PubMed - indexed for MEDLINE]