Publications by authors named "Kevin Hines"

37 Publications

Two-Stage Hierarchical Group Testing Strategy to Increase SARS-CoV-2 Testing Capacity at an Institution of Higher Education: A Retrospective Analysis.

J Mol Diagn 2021 Sep 22. Epub 2021 Sep 22.

Life Science Testing Center, Northeastern University, Burlington, Massachusetts, USA. Electronic address:

Population testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is necessary owing to the potential for viral transmission from asymptomatic cases, yet scarcity of reagents and equipment has increased the cost-prohibitive implementation of screening campaigns at institutions of higher education. Significant analytical sensitivities of nucleic acid amplification methods permit sample pooling to increase testing capacity. Statistical models compared optimal testing configuration for pools of 3, 5, and 10 samples. Assessment of pooling using the TaqPath COVID-19 Combo Kit multiplex assay (ORF1ab, N, and S gene targets) involved a limit of detection (LOD) study, matrix effect study, and clinical comparison of neat to pooled sample. An LOD of 135.02 (ORF1ab; CI.95: 117.21-155.52), 373.92 (N; CI.95: 257.05-437.64), and 1001.32 (S; CI.95: 896.62-1118.33) gce per milliliter was resolved. Seventy-two randomly selected samples demonstrated slight suppression due to negative sample matrix. Resulting mean cycle threshold (CT) shifts were 2.09 (ORF1ab), 1.76 (N), and 2.31 (S) for the 3-pool, 2.83 (ORF1ab), 2.45 (N), and 3.24 (S) for the 5-pool, and 3.99 (ORF1ab), 3.46 (N), and 4.07 (S) for the 10-pool. Despite quantitative sensitivity loss trend, the qualitative result was unaffected in each pool. According to the range of disease prevalence observed at the testing site (0.03-7.32%), a pool of five samples was deemed an optimal and cost-effective option for monitoring the Northeastern University community.
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http://dx.doi.org/10.1016/j.jmoldx.2021.09.001DOI Listing
September 2021

Lumbar Total Disc Replacement: Current Usage.

Neurosurg Clin N Am 2021 Oct;32(4):511-519

Department of Neurological Surgery, Thomas Jefferson University Hospitals, 909 Walnut Street, Room 320L, Philadelphia, PA 19107, USA.

Low back pain is the leading cause of disability worldwide in industrialized nations. The pathology underlying chronic low back pain is associated with numerous factors. Lumbar degenerative disc disease is a potential major source of low back pain. There are numerous treatment modalities and options. Nonsurgical treatment options exist in the form of pain management through a combination of anti-inflammatory medications and steroid injections, physical therapy and lifestyle modifications. This article reviews the history and current trends in use for lumbar toral disc arthroplasty for degenerative disc disease treatment. Furthermore, indications, contraindications, and complications management are discussed.
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http://dx.doi.org/10.1016/j.nec.2021.05.010DOI Listing
October 2021

Independent Predictors of Revision Lumbar Fusion Outcomes and the Impact of Spine Surgeon Variability: Does It Matter Whether the Primary Surgeon Revises?

Neurosurgery 2021 Aug 14. Epub 2021 Aug 14.

Jefferson Hospital for Neuroscience, Department of Neurosurgery, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.

Background: There is a paucity of information regarding treatment strategies and variables affecting outcomes of revision lumbar fusions.

Objective: To evaluate the influence of primary vs different surgeon on functional outcomes of revisions.

Methods: All elective lumbar fusion revisions, March 2018 to August 2019, were retrospectively categorized as performed by the same or different surgeon who performed the primary surgery. Oswestry Disability Index (ODI) and clinical variables were collected. Multiple logistic regression identified multivariable-adjusted odds ratio (OR) of independent variables analyzed.

Results: Of the 130 cases, 117 (90%) had complete data. There was a slight difference in age in the same (median: 59; interquartile range [IQR], 54-66) and different surgeon (median: 67; IQR, 56-72) groups (P = .02); all other demographic variables were not significantly different (P > .05). Revision surgery with a different surgeon had an ODI improvement (median: 8; IQR, 2-14) greater than revisions performed by the same surgeon (median: 1.5; IQR, -3 to 10) (P < .01). Revisions who achieved minimum clinically important difference (MCID) performed by different surgeon (59.7%) were also significantly greater than the ones performed by the same surgeon (40%) (P = .042). Multivariate analysis demonstrated that a different surgeon revising (OR, 2.37; [CI]: 1.007-5.575, P = .04) was an independent predictor of MCID achievement, each additional 2 years beyond the last surgery conferred a 2.38 ([CI]: 1.36-4.14, P < .01) times greater odds of MCID achievement, and the anterior lumbar interbody fusion approach decreased the chance of achieving MCID (OR, 0.19; [CI]: 0.04-0.861, P = .03).

Conclusion: All revision lumbar spinal fusion approaches may not achieve the same outcomes. This analysis suggests that revision surgeries may have better outcomes when performed by a different surgeon.
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http://dx.doi.org/10.1093/neuros/nyab300DOI Listing
August 2021

Absence of carbonic anhydrase in chloroplasts affects C plant development but not photosynthesis.

Proc Natl Acad Sci U S A 2021 Aug;118(33)

Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853;

The enzyme carbonic anhydrase (CA), which catalyzes the interconversion of bicarbonate with carbon dioxide (CO) and water, has been hypothesized to play a role in C photosynthesis. We identified two tobacco stromal CAs, β-CA1 and β-CA5, and produced CRISPR/Cas9 mutants affecting their encoding genes. While single knockout lines - and had no striking phenotypic differences compared to wild type (WT) plants, - leaves developed abnormally and exhibited large necrotic lesions even when supplied with sucrose. Leaf development of - plants normalized at 9,000 ppm CO Leaves of - mutants and WT that had matured in high CO had identical CO fixation rates and photosystem II efficiency. Fatty acids, which are formed through reactions with bicarbonate substrates, exhibited abnormal profiles in the chloroplast CA-less mutant. Emerging - leaves produce reactive oxygen species in chloroplasts, perhaps due to lower nonphotochemical quenching efficiency compared to WT. - seedling germination and development is negatively affected at ambient CO Transgenes expressing full-length β-CA1 and β-CA5 proteins complemented the mutation but inactivated (ΔZn-βCA1) and cytoplasm-localized (Δ62-βCA1) forms of β-CA1 did not reverse the growth phenotype. Nevertheless, expression of the inactivated ΔZn-βCA1 protein was able to restore the hypersensitive response to tobacco mosaic virus, while and plants failed to show a hypersensitive response. We conclude that stromal CA plays a role in plant development, likely through providing bicarbonate for biosynthetic reactions, but stromal CA is not needed for maximal rates of photosynthesis in the C plant tobacco.
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http://dx.doi.org/10.1073/pnas.2107425118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8379964PMC
August 2021

Clinical outcomes in revision lumbar spine fusions: an observational cohort study.

J Neurosurg Spine 2021 Aug 6:1-9. Epub 2021 Aug 6.

Objective: The authors compared primary lumbar spine fusions with revision fusions by using patient Oswestry Disability Index (ODI) scores to evaluate the impact of the North American Spine Society (NASS) evidence-based medicine (EBM) lumbar fusion indications on patient-reported outcome measures of revision surgeries.

Methods: This study was a retrospective analysis of a prospective observational cohort of patients who underwent elective lumbar fusion between January 2018 and December 2019 at a single quaternary spine surgery service and had a minimum of 6 months of follow-up. A prospective quality improvement database was constructed that included the data from all elective lumbar spine surgeries, which were categorized prospectively as primary or revision surgeries and EBM-concordant or EBM-discordant revision surgeries based on the NASS coverage EBM policy. In total, 309 patients who met the inclusion criteria were included in the study. The ODIs of all groups (primary, revision, revision EBM concordant, and revision EBM discordant) were statistically compared. Differences in frequencies between cohorts were evaluated using chi-square and Fisher's exact tests. The unpaired 2-tailed Student t-test and the Mann-Whitney U-test for nonparametric data were used to compare continuous variables. Logistic regression was performed to determine the associations between independent variables (surgery status and NASS criteria indications) and functional outcomes.

Results: Primary lumbar fusions were significantly associated with improved functional outcomes compared with revisions, as evidenced by ODI scores (OR 1.85, 95% CI 1.16-2.95 to achieve a minimal clinically important difference, p = 0.01). The percentage of patients whose functional status had declined at the 6-month postoperative evaluation was significantly higher in patients who had undergone a revision surgery than in those who underwent a primary surgery (23% vs 12.3%, respectively). An increase in ODI score, indicating worse clinical outcome after surgery, was greater in patients who underwent revision procedures (OR 2.14, 95% CI 1.17-3.91, p = 0.0014). Patients who underwent EBM-concordant revision surgery had significantly improved mean ODI scores compared with those who underwent EBM-discordant revision surgery (7.02 ± 5.57 vs -4.6 ± 6.54, p < 0.01).

Conclusions: The results of this prospective quality improvement program investigation illustrate that outcomes of primary lumbar fusions were superior to outcomes of revisions. However, revision procedures that met EBM guidelines were associated with greater improvements in ODI scores, which indicates that the use of defined EBM guideline criteria for reoperation can improve clinical outcomes of revision lumbar fusions.
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http://dx.doi.org/10.3171/2020.12.SPINE201908DOI Listing
August 2021

Single-Center Retrospective Analysis of Device-Related Complications Related to Dorsal Root Ganglion Stimulation for Pain Relief in 31 Patients.

Neuromodulation 2021 Jul 26. Epub 2021 Jul 26.

Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA, USA.

Introduction: Dorsal root ganglion (DRG) stimulation is a form of neuromodulation used to treat neuropathic pain due to a myriad of etiologies. Though this relatively new therapy has been shown to be quite effective, complications associated with the implantation of this therapy have not been well documented.

Objectives: The primary objective of this study was to describe the device-related complications associated with DRG stimulator implantations.

Materials And Methods: This was a single-center retrospective analysis of 31 patients who underwent full implantation of neuromodulation hardware marketed for DRG stimulation. The predefined endpoints included device-related complications associated with DRG implantations, such as hardware failure, explantation procedures, and revision surgery. Additional endpoints included percentage of patients receiving therapy and pain as measured using the visual analog scale (VAS) pain scale at initial, six-month, and 12-month follow-up after hardware implantation.

Results: Thirty-one patients were included out of 42 patients trialed. Baseline VAS in patients was 7.7 (31 patients). At initial follow-up, six-month follow-up, and one-year follow-up, VAS scores were 4.7 (31 patients), 5.3 (20 patients), and 5.5 (13 patients), respectively. Paired t-test between preoperative VAS (mean 7.3) and one-year follow-up VAS (5.5) demonstrated statistical significance (p = 0.027). At initial, six-month, and one-year follow-up, 30/31 (97%), 19/24 (79%), and 18/23 (78%) patients were confirmed to be receiving DRG stimulation therapy after permanent implant. Of the 31 patients who were implanted with a permanent system, 8 (26%) were explanted and an additional 10 (29%) required revision surgery.

Conclusion: In this study, we examine the various device-related complications associated with DRG stimulation requiring repeat surgery. High rates of hardware failure, revision surgery, and explantation of stimulators illustrate the need for hardware optimization to improve patient outcomes.
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http://dx.doi.org/10.1111/ner.13498DOI Listing
July 2021

The Impact of Incorporating Evidence-Based Guidelines for Lumbar Fusion Surgery in Neurosurgical Resident Education.

World Neurosurg 2021 Jul 20. Epub 2021 Jul 20.

Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA.

Background: Instrumented fusion procedures are essential in the treatment of degenerative lumbar spine disease to alleviate pain and improve neurological function, but they are being performed with increasing incidence and variability. We implemented a training module for neurosurgery residents that is based on evidence-based criteria for lumbar fusion surgery and measured its effectiveness in residents' decision making regarding whether patients should or should not undergo instrumented fusion.

Methods: The study design was a pretest versus posttest experiment conducted from September 2019 until July 2020 to measure improvement after formalized instruction on evidence-based guidelines. Neurosurgery residents of all training levels at our institution participated. A test was administered at the beginning of each academic year. The highest possible score was 18 points in each pretest and posttest.

Results: There was a general trend of test score improvement across all levels of training with a greater degree of change for participants with lower compared with higher pretest scores, indicating a possible ceiling effect. Paired t test demonstrated an overall mean score increase of 2 points (P < 0.0001), equivalent to an 11.11% increase (P < 0.0001). Stratified by training group, mean absolute change in test score was 2 (P = 0.0217), 1.67 (P = 0.0108), and 2.25 (P = 0.0173) points for junior, midlevel, and senior training groups, respectively.

Conclusions: Incorporating a targeted evidence-based learning module for lumbar spine fusion surgery can improve neurosurgery residents' clinical decision making toward a more uniform practice supported by published data.
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http://dx.doi.org/10.1016/j.wneu.2021.07.045DOI Listing
July 2021

Are Lumbar Fusion Guidelines Followed? A Survey of North American Spine Surgeons.

Neurospine 2021 Jun 30;18(2):389-396. Epub 2021 Jun 30.

Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA.

Objective: To evaluate the use of guidelines for lumbar spine fusions among spine surgeons in North America.

Methods: An anonymous survey was electronically sent to all AO Spine North America members. Survey respondents were asked to indicate their opinion surrounding the suitability of instrumented fusion in a variety of clinical scenarios. Fusion indications in accordance with North America Spine Society (NASS) guidelines for lumbar fusion were considered NASS-concordant answers. Respondents were considered to have a NASS-concordant approach if ≥ 70% (13 of 18) of their answers were NASS-concordant answers. Comparisons were performed using bivariable statistics.

Results: A total of 105 responses were entered with complete data available on 70. Sixty percent of the respondents (n = 42) were considered compliant with NASS guidelines. NASS-discordant responses did not differ between surgeons who stated that they include the NASS guidelines in their decision-making algorithm (5.10 ± 1.96) and those that did not (4.68 ± 2.09) (p = 0.395). The greatest number of NASS-discordant answers in the United States. was in the South (5.75 ± 2.09), with the lowest number in the Northeast (3.84 ± 1.70) (p < 0.01). For 5 survey items, rates of NASS-discordant answers were ≥ 40%, with the greatest number of NASS-discordant responses observed in relation to indications for fusion in spinal deformity (80%). Spine surgeons utilizing a NASS-concordant approach had a significant lower number of NASS-discordant answers for synovial cysts (p = 0.03), axial low back pain (p < 0.01), adjacent level disease (p < 0.01), recurrent stenosis (p < 0.01), recurrent disc herniation (p = 0.01), and foraminal stenosis (p < 0.01).

Conclusion: This study serves an important role in clarifying the rates of uptake of clinical practice guidelines in spine surgery as well as to identify barriers to their implementation.
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http://dx.doi.org/10.14245/ns.2142136.068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8255757PMC
June 2021

Operative versus Nonoperative Management of Idiopathic Spinal Cord Herniation: Effect on Symptomatology and Disease Progression.

World Neurosurg 2021 Aug 24;152:e149-e154. Epub 2021 May 24.

Department of Neurosurgery, Thomas Jefferson University, Philadelphia, Pennsylvania, USA. Electronic address:

Background: Idiopathic spinal cord herniation (ISCH) is a rare pathology characterized by extravasation of the spinal cord through a dural defect. The optimal algorithm for choosing operative or nonoperative management is not well elucidated, partially because of the rarity of this pathology. We present the largest single-center series of ISCH and compare operative treatment to conservative management.

Methods: A retrospective case series of all patients evaluated for treatment of ISCH at our institution between 2010 and 2019 was conducted. Demographic variables, presenting symptoms, and imaging characteristics were assessed for all patients. For patients who underwent operative treatment, surgical approach, postoperative course, and discharge outcomes were recorded. Follow-up notes were reviewed for status of symptoms and functional capabilities, which were synthesized into Odom's criteria score.

Results: Sixteen patients met the inclusion criteria for this study, 8 of whom underwent operative treatment. No significant differences were found between operative and nonoperative groups with regard to demographic variables or pathology characteristics. Odom's criteria scores for the operative cohort were 12.5% (1 of 8) Excellent, 62.5% (5 of 8) Good, 12.5% (1 of 8) Fair, and 12.5% (1 of 8) Poor. Odom's criteria scores for the nonoperative cohort were 16.7% (1 of 6) Excellent, 33.3% (2 of 6) Good, 16.7% (1 of 6) Fair, and 33.3% (2 of 6) Poor. There was no significant difference between Odom's criteria score distribution between the operative and nonoperative groups at latest follow up (P = 0.715).

Conclusions: Conservative management of spinal cord herniation is an option that does not preclude symptomatic improvement in patients with idiopathic spinal cord herniation.
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http://dx.doi.org/10.1016/j.wneu.2021.05.046DOI Listing
August 2021

Extruded disc causes acute cervical epidural hematoma and cord compression: a case report.

Spinal Cord Ser Cases 2021 May 21;7(1):39. Epub 2021 May 21.

Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA.

Introduction: Cervical spontaneous epidural hematoma is a serious neurosurgical pathology that often requires prompt surgical intervention. While a variety of causes may contribute, the authors present the first case in the literature of cervical disc extrusion provoking epidural hemorrhage and acute neurological deterioration.

Case Presentation: A 65 year old male presented with six months of worsening signs and symptoms of cervical myelopathy. He had progressive deterioration over the course of two weeks leading to ambulatory dysfunction requiring a cane for assistance. While undergoing his medical workup in the emergency department, the patient became acutely plegic in the right lower extremity prompting emergent surgical decompression and stabilization.

Discussion: Based on imaging, pathology, and intraoperative findings, it was concluded that the patient had an extruded disc segment that may have precipitated venous bleeding in the epidural space and findings of acute cervical cord compression. Cervical disc extrusion may lead to venous damage, epidural hematoma, and spinal cord compression. If this unique presentation is recognized and addressed in a timely manner, patient outcomes may still be largely positive as this case demonstrates.
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http://dx.doi.org/10.1038/s41394-021-00403-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8140160PMC
May 2021

Long-segment posterior cervical decompression and fusion: does caudal level affect revision rate?

J Neurosurg Spine 2021 Apr 23:1-7. Epub 2021 Apr 23.

1Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia; and.

Objective: Posterior cervical decompression and fusion (PCDF) is a commonly performed procedure to address cervical myelopathy. A significant number of these patients require revision surgery for adjacent-segment disease (ASD) or pseudarthrosis. Currently, there is no consensus among spine surgeons on the inclusion of proximal thoracic spine instrumentation. This study investigates the benefits of thoracic extension in long-segment cervical fusions and the potential drawbacks. The authors compare outcomes in long-segment subaxial cervical fusion for degenerative cervical myelopathy with caudal vertebral levels of C6, C7, and T1.

Methods: A retrospective analysis identified 369 patients who underwent PCDF. Patients were grouped by caudal fusion level. Reoperation rates for ASD and pseudarthrosis, infection, and blood loss were examined. Data were analyzed with chi-square, 1-way ANOVA, and logistic regression.

Results: The total reoperation rate for symptomatic pseudarthrosis or ASD was 4.8%. Reoperation rates, although not significant, were lower in the C3-6 group (2.6%, vs 8.3% for C3-7 and 3.8% for C3-T1; p = 0.129). Similarly, rates of infection were lower in the shorter-segment fusion without achieving statistical significance (2.6% for C3-6, vs 5.6% for C3-7 and 5.5% for C3-T1; p = 0.573). The mean blood loss was documented as 104, 125, and 224 mL for groups 1, 2, and 3, respectively (p < 0.001).

Conclusions: Given the lack of statistical difference in reoperation rates for long-segment cervical fusions ending at C6, C7, or T1, shorter fusions in high-risk surgical candidates or elderly patients may be performed without higher rates of reoperation.
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http://dx.doi.org/10.3171/2020.10.SPINE201385DOI Listing
April 2021

Bundled Payment Models in Spine Surgery.

Global Spine J 2021 Apr;11(1_suppl):7S-13S

Department of Neurosurgery, 6559Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA.

Study Design: The following is a narrative discussion of bundled payments in spine surgery.

Objective: The cost of healthcare in the United States has continued to increase. To lower the cost of healthcare, reimbursement models are being investigated as potential cost saving interventions by driving incentives and quality improvement in fields such a spine surgery.

Methods: Narrative overview of literature pertaining to bundled payments in spine surgery synthesizing findings from computerized databases and authoritative texts.

Results: Spine surgery is challenging to define payment modes because of high cost variability and surgical decision-making nuances. While implementing bundled care payments in spine surgery, it is important to understand concepts such as value-based purchasing, episodes of care, prospective versus retrospective payment models, one versus two-sided risk, risk adjustment, and outlier protection. Strategies for implementation underscore the importance of risk stratification and modeling, adoption of evidence based clinical pathways, and data collection and dissemination. While bundled care models have been successfully implemented, challenges facing institutions adopting bundled care payment models include financial stressors during adoption of the model, distribution of risks, incentivization of treating only low risk patients, and nuanced variation in procedures leading to variation in costs.

Conclusion: An alternative for fee for service payments, bundled care payments may lead to higher cost savings and surgeon accountability in a patient's care.
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http://dx.doi.org/10.1177/2192568220974977DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8076809PMC
April 2021

Prediction of hematoma expansion in spontaneous intracerebral hemorrhage: Our institutional experience.

J Clin Neurosci 2021 Apr 19;86:271-275. Epub 2021 Feb 19.

Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, United States. Electronic address:

Background: Spontaneous intracerebral hemorrhage (sICH) is a disease process with high morbidity and mortality. In particular, hematoma expansion (HE) is a feared complication of sICH. With 15-40% of patients experiencing HE, it has become increasingly important to predict which sICH will remain stable and which will expand.

Objective: With new treatment options being developed, it is becoming increasingly important to be able to predict which hemorrhages are at high versus low risk for expansion. The authors of this study hope to reexamine variables associated with hematoma expansion in hopes of generating newer data on risk factors for expansion.

Methods: A retrospective analysis identified 334 patients who presented with sICH. The primary outcome was HE on follow up head CT. HE was defined as a greater than 33% increase or an absolute increase in 6 mL or more in overall volume between the two sets of CT images. Analysis was performed using unpaired t-test, Chi-square, and Fisher's exact tests, as appropriate.

Results: Of the 334 patients, 247 (74.0%) did not experience an expansion of their ICH while 87 (26.0%) did. Multivariable logistic regression was performed demonstrating ICH score of 3 or greater (4.76 (95% CI 2.60-8.72, p < 0.001) , cortical location of the sICH (1.77 (95% CI 1.03-3.04, p = 0.038), and presence of a fluid level (6.46 (95% CI 2.28-18.3, p < 0.001) as significant predictors of HE.

Conclusions: Our study found that fluid-fluid levels on non-contrast CT, an ICH score 3 or greater, and lobar sICH were all more likely to expand.
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http://dx.doi.org/10.1016/j.jocn.2021.01.046DOI Listing
April 2021

Are Guidelines Important? Results of a Prospective Quality Improvement Lumbar Fusion Project.

Neurosurgery 2021 06;89(1):77-84

Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA.

Background: United States (U.S.) healthcare is a volume-based inefficient delivery system. Value requires the consideration of quality, which is lacking in most healthcare disciplines.

Objective: To assess whether patients who met specific evidence-based medicine (EBM)-based criteria preoperatively for lumbar fusion would achieve higher rates of achieving the minimal clinical important difference (MCID) than those who did not meet the EBM indications.

Methods: All elective lumbar fusion cases, March 2018 to August 2019, were prospectively evaluated and categorized based on EBM guidelines for surgical indications. The MCID was defined as a reduction of ≥5 points in Oswestry Disability Index (ODI). Multiple logistic regression identified multivariable-adjusted odds ratio of EBM concordance.

Results: A total of 325 lumbar fusion patients were entered with 6-mo follow-up data available for 309 patients (95%). The median preoperative ODI score was 24.4 with median 6-mo improvement of 7.0 points (P < .0001). Based on ODI scores, 79.6% (246/309) improved, 3.8% (12/309) had no change, and 16% (51/309) worsened. A total of 191 patients had ODI improvement reaching the MCID. 93.2% (288/309) cases were EBM concordant, while 6.7% (21/309) were not.In multivariate analysis, EBM concordance (P = .0338), lower preoperative ODI (P < .001), lower ASA (American Society of Anesthesiologists) (P = .0056), and primary surgeries (P = .0004) were significantly associated with improved functional outcome. EBM concordance conferred a 3.04 (95% CI 1.10-8.40) times greater odds of achieving MCID in ODI at 6 mo (P = .0322), adjusting for other factors.

Conclusion: This analysis provides validation of EBM guideline criteria to establish optimal patient outcomes. The EBM concordant patients had a greater than 3 times improved outcome compared to those not meeting EBM fusion criteria.
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http://dx.doi.org/10.1093/neuros/nyab062DOI Listing
June 2021

The Impact of Intraoperative Image-Guidance Modalities and Neurophysiologic Monitoring in the Safety of Sacroiliac Fusions.

Global Spine J 2021 Jan 12:2192568220981977. Epub 2021 Jan 12.

Department of Neurosurgery, 6559Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, PA, USA.

Study Design: Retrospective observational cohort.

Objective: A review of efficiency and safety of fluoroscopy and stereotactic navigation system for minimally invasive (MIS) Sacroiliac (SI) fusion through a lateral technique.

Methods: Retrospective analysis of an observational cohort of 96 patients greater than 18 years old, that underwent MIS SI fusion guided by fluoroscopy or navigation between January 2013 and April 2020 with a minimum of 3 months follow-up. Intraoperative neuromonitoring (IONM) with a variable combination of electromyography (EMG), somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) was also utilized.

Results: The overall complication rate in the study was 9.4%, and there was no difference between the fluoroscopy (10.1%), and navigation groups (8%). Neurological complication rate was 2.1%, without a significant difference between both intraoperative guidance modality groups (p = 0.227). There was a significant difference between the modalities of IONM used and the occurrence of neurological injury (p = 0.01).The 2 patients who had a neurological complication postoperatively were monitored only with EMG and SSEP, but none of the patients (n = 76) in which MEPs were utilized had neurologic complication. The mean pain improvement 3 months after surgery was greater in the navigation group (2.44 ± 2.72), but was not statistically different than the improvement in the fluoroscopy group (1.90 ± 2.07) (p = 0.301).

Conclusions: No difference in the safety of the procedure was found between the fluoroscopy and the stereotactic navigation techniques. The contribution of the IONM to the safety of SI fusions could not be determined, but the data indicates that MEPs provide the highest level of sensitivity.
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http://dx.doi.org/10.1177/2192568220981977DOI Listing
January 2021

Combined Anterior Osteophytectomy and Cricopharyngeal Myotomy for Treatment of DISH-Associated Dysphagia.

Global Spine J 2020 Nov 18:2192568220967358. Epub 2020 Nov 18.

Thomas Jefferson University, Philadelphia, PA, USA.

Study Design: Retrospective observational case series.

Objective: To assess the outcome of patients with diffuse idiopathic skeletal hyperostosis (DISH) with dysphagia who underwent cricopharyngeal myotomy (CPM) in conjunction with anterior osteophytectomy (OP).

Methods: This is a retrospective observational study of 9 patients that received combined intervention by neurosurgeons and otolaryngologists. Inclusion criteria for surgery consisted of patients who failed to respond to conservative treatments for dysphagia and had evidence of both upper esophageal dysfunction and osteophyte compression. We present the largest series in literature to date including patients undergoing combined OP and CPM.

Results: A total of 88.9% (8/9) of the patients who underwent OP and CPM showed improvement in their symptoms. Of the aforementioned group, 22.2% of these patients had complete resolution of their symptoms, 11.1% did not improve, and only 2 patients showed recurrence of their symptoms. None of the patients in whom surgery was performed required reoperation or suffered serious complication related to the surgical procedures.

Conclusion: Based on the literature results, high rate of improvements in dysphagia, and low rate of complications, combined OP and CPM procedures may be beneficial to a carefully selected group of patients.
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http://dx.doi.org/10.1177/2192568220967358DOI Listing
November 2020

Reference accuracy in spine surgery.

J Neurosurg Spine 2020 Sep 25:1-5. Epub 2020 Sep 25.

1Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania.

Objective: The references list is an important part of a scientific article that serves to confirm the accuracy of the authors' statements. The goal of this study was to evaluate the reference accuracy in the field of spine surgery.

Methods: Four major peer-reviewed spine surgery journals were chosen for this study based on their subspecialty clinical impact factors. Sixty articles per journal were selected from 12 issues each of The Spine Journal, Spine, and Journal of Neurosurgery: Spine, and 40 articles were selected from 8 issues of Global Spine Journal, for a total of 220 articles. All the articles were published in 2019 and were selected using computer-generated numbers. From the references list of each article, one reference was again selected by using a computer-generated number and then checked for citation or quotation errors.

Results: The results indicate that 84.1% of articles have a minor citation error, 4.5% of articles have a major citation error, 9.5% of articles have a minor quotation error, and 9.1% of articles have a major quotation error. Journal of Neurosurgery: Spine had the fewest citation errors compared with the other journals evaluated in this study. Using chi-square analysis, no association was determined between the occurrence of errors and potential markers of reference mistakes. Still, statistical significance was found between the occurrence of citation errors and the spine journals tested.

Conclusions: In order to advance medical treatment and patient care in spine surgery, detailed documentation and attention to detail are necessary. The results from this study illustrate that improved reference accuracy is required.
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http://dx.doi.org/10.3171/2020.6.SPINE20640DOI Listing
September 2020

How accurate is the neurosurgery literature? A review of references.

Acta Neurochir (Wien) 2021 01 22;163(1):13-18. Epub 2020 Sep 22.

Division of Spine and Peripheral Nerve Surgery, Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, 901 Walnut Street 3rd Floor, Philadelphia, PA, 19107, USA.

Background: The reference list is an important part of academic manuscripts. The goal of this study is to evaluate the reference accuracy in the field of neurosurgery.

Methods: This study examines four major peer-reviewed neurosurgery journals, chosen based on their clinical impact factor: Neurosurgery, J Neurosurg, World Neurosurg, and Acta Neurochir. For each of the four journals, five articles from each of the journal's 12 issues published in 2019 were randomly selected using an online generator. This resulted in a total of 240 articles, 60 from each journal. Additionally, from each article's list of references, one reference was again randomly selected and checked for a citation or quotation error. The chi-square test was used to analyze the association between the occurrence of citation and quotation errors and the presence of hypothesized risk factors that could impact reference accuracy.

Results: 62.1% of articles had a minor citation error, 8.33% had a major citation error, 12.1% had a minor quotation error, and 5.8% of articles had a major quotation error. Overall, Acta Neurochir presented with the fewest quotation errors compared with the other journals evaluated. The only association between the frequency of errors and potential markers of reference mistakes was with the length of the bibliography. Surprisingly, this correlation indicated that the articles with longer reference lists had fewer citation errors (p < 0.01). Statistical significance was found between the occurrence of citation errors and the journals of publication (p < 0.01).

Conclusions: In order to advance medical treatment and patient care in neurosurgery, detailed documentation and attention to detail are necessary. The results from this analysis illustrate that improved reference accuracy is required.
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http://dx.doi.org/10.1007/s00701-020-04576-3DOI Listing
January 2021

Cranial Settling Causing Intracranial Hemorrhage Through Violation of the Skull Base by Cervical Spine Instrumentation.

World Neurosurg 2021 01 2;145:178-182. Epub 2020 Sep 2.

Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA.

Background: Rheumatoid arthritis (RA) is a chronic inflammatory polyarthropathy that affects many synovial joints favoring the hands, knees, and vertebral articulations. Joint laxity manifests as subaxial instability, atlantoaxial instability, and cranial settling (CS).

Case Description: A 70-year-old woman with past medical history of RA, Hashimoto's thyroiditis, osteoporosis, history of C1-2 fusion for instability 15 years prior, with subsequent revision cervicothoracic fusion for degeneration, and trauma 2 years prior presents with new onset headache, nausea, and vomiting of 36-hour duration. Neurologic examination was only notable for mild right dysmetria. Workup revealed acute hemorrhage in the posterior fossa with migration of the right rod implant and screw tulip, as a result of CS. The patient underwent occipital-cervical fusion with removal of the migratory hardware.

Conclusions: Intracranial rod migration and hemorrhage secondary to CS is a rare complication that must be brought to the attention of surgeons operating on patients with RA.
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http://dx.doi.org/10.1016/j.wneu.2020.08.193DOI Listing
January 2021

Neurosurgical Evaluation for Patients with Chronic Lower Back Pain.

Curr Pain Headache Rep 2020 Aug 17;24(10):58. Epub 2020 Aug 17.

Department of Neurological Surgery, Thomas Jefferson University Hospital, 909 Walnut Street, Clinical Office Building, 2nd floor, Philadelphia, PA, 19107, USA.

Purpose Of Review: Chronic low back pain (CLBP) is a major cause of disability in the USA, and it affects approximately 1 in 4 Americans. CLBP patients are commonly referred to or seek out neurosurgical evaluations and opinions for treatment and management.

Recent Findings: Literature shows that only a minority of patients with CLBP may benefit from a surgical procedure. These patients that present to clinic often have been ailing for a considerable amount of time and are eager for effective treatment to alleviate pain. However, determining if a patient with CLBP is a surgical candidate is predicated upon having no success of pain relief with non-operative management. Patients with CLBP require thorough and adequate imaging, clinical exam, and diagnostic evaluation. When adequate non-operative management was provided, and proven fruitless, the patient may be considered an operative candidate. In this manuscript, a framework is presented for workup and evaluation of patients with CLBP.
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http://dx.doi.org/10.1007/s11916-020-00894-4DOI Listing
August 2020

The Implications of Paraspinal Muscle Atrophy in Low Back Pain, Thoracolumbar Pathology, and Clinical Outcomes After Spine Surgery: A Review of the Literature.

Global Spine J 2020 Aug 9;10(5):657-666. Epub 2019 Oct 9.

Thomas Jefferson University, Philadelphia, PA, USA.

Study Design: Literature review.

Objectives: Paraspinal muscle integrity is believed to play a critical role in low back pain (LBP) and numerous spinal deformity diseases and other pain pathologies. The influence of paraspinal muscle atrophy (PMA) on the clinical and radiographic success of spinal surgery has not been established. We aim to survey the literature in order to evaluate the impact of paraspinal muscle atrophy on low back pain, spine pathologies, and postoperative outcomes of spinal surgery.

Methods: A review of the literature was conducted using a total of 267 articles identified from a search of the PubMed database and additional resources. A full-text review was conducted of 180 articles, which were assessed based on criteria that included an objective assessment of PMA in addition to measuring its relationship to LBP, thoracolumbar pathology, or surgical outcomes.

Results: A total of 34 studies were included in this review. The literature on PMA illustrates an association between LBP and both decreased cross-sectional area and increased fatty infiltration of paraspinal musculature. Atrophy of the erector spinae and psoas muscles have been associated with spinal stenosis, isthmic spondylolisthesis, facet arthropathy, degenerative lumbar kyphosis. A number of studies have also demonstrated an association between PMA and worse postoperative outcomes.

Conclusions: PMA is linked to several spinal pathologies and some studies demonstrate an association with worse postoperative outcomes following spinal surgery. There is a need for further research to establish a relationship between preoperative paraspinal muscle integrity and postoperative success, with the potential for guiding surgical decision making.
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http://dx.doi.org/10.1177/2192568219879087DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359686PMC
August 2020

Telemedicine for the Spine Surgeon in the Age of COVID-19: Multicenter Experiences of Feasibility and Implementation Strategies.

Global Spine J 2021 May 3;11(4):608-613. Epub 2020 Jun 3.

23217Thomas Jefferson University Hospital, Philadelphia, PA, USA.

Study Design: Multicenter study.

Objectives: The COVID-19 pandemic has obligated physicians to recur to additional resources and make drastic changes regarding the standard physician-patient encounter. In the last century, there has been a substantial improvement in technology, which over the years has opened the door to a new form of medical practicing known as telemedicine.

Methods: Healthcare workers from three hospitals involved in the care for COVID-19 patients in the united states were invited to share their experience using telemedicine to deliver clinical care to their patients.

Results: Since the appearance of this worldwide outbreak, social distancing has been a key factor in preventing the spread of the virus, for which measures have been taken to limit physical contact. Because of the ongoing situation, telemedicine has been progressively incorporated into the physician-patient encounters and quickly has become an essential component in the day-today medical practice.

Conclusions: It is feasible to deliver viable spine practice with the use of telemedicine. A proper patient selection of patients requiring virtual treatment versus those requiring in-person visits should be considered.
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http://dx.doi.org/10.1177/2192568220932168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119918PMC
May 2021

Intracranial Pressure and Brain Tissue Oxygen Neuromonitoring in Pediatric Cerebral Malaria.

World Neurosurg 2020 09 9;141:115-118. Epub 2020 Jun 9.

Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA.

Background: Pediatric cerebral malaria (CM) is a severe complication of Plasmodium falciparum that often leaves survivors with severe neurologic impairment. Increased intracranial pressure (ICP) as a result of cerebral edema has been identified as a major predictor of morbidity and mortality in CM. Past studies have demonstrated that survivors are more likely to have resolution of elevated ICP and that efficient management of ICP crises may lead to better outcomes. However, data on invasive brain tissue oxygen monitoring are unknown.

Case Description: We report a case of a pediatric patient with cerebral malaria who developed encephalopathy and cerebral edema and describe the pathophysiology of this disease process with invasive ICP and brain tissue oxygen multimodality neuromonitoring. The utilization of both ICP and brain tissue oxygen monitoring allowed prompt diagnosis and successful treatment of severe intracranial hypertension and low brain tissue oxygenation crisis. The patient was discharged to home in good neurologic condition.

Conclusions: Multimodality neuromonitoring may be considered in pediatric patients who have cerebral edema and encephalopathy from CM.
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http://dx.doi.org/10.1016/j.wneu.2020.06.024DOI Listing
September 2020

The Role of Cricopharyngeal Myotomy After Anterior Cervical Decompression and Fusion Operations.

World Neurosurg 2020 05 7;137:146-148. Epub 2020 Feb 7.

Department of Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA.

Background: Anterior cervical spine surgeries have low morbidity, sufficient surgical corridor, and quick recovery times. Although largely considered a safe and effective procedure to address cervical myelopathy, radiculopathy, and deformity, dysphagia is a frequent yet poorly understood adverse event. One treatment is cricopharyngeal myotomy (CPM), which aids in swallowing for patients with refractory issues after anterior cervical decompression and fusion (ACDF).

Case Description: Here we describe our experience with 6 patients requiring revision ACDF with preoperative dysphagia who were treated with concurrent revision and CPM. Our series demonstrated that CPM is an effective and safe procedure used in combination with an ACDF. In our series, we had 6 patients with dysphagia preoperatively who were all able to undergo ACDF without worsening of their dysphagia despite having risk factors predisposing them to this complication. In our series, 83% of patients either improved or experienced resolution of their symptoms with only 1 patient failing to improve.

Conclusions: Given its efficacy and safety, patients planned for ACDF with preoperative dysphagia should be evaluated by ENT for potential CPM.
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http://dx.doi.org/10.1016/j.wneu.2020.01.180DOI Listing
May 2020

A Brief History of Quality Improvement in Health Care and Spinal Surgery.

Global Spine J 2020 Jan 6;10(1 Suppl):5S-9S. Epub 2020 Jan 6.

Thomas Jefferson University, Philadelphia, PA, USA.

While medical and technological advances continue to shape and advance health care, there has been growing emphasis on translating these advances into improvement in overall health care quality outcomes in the United States. Innovators such as Abraham Flexner and Ernest Codman engaged in rigorous reviews of systems and patient outcomes igniting wider spread interest in quality improvement in health care. Codman's efforts even contributed to the founding of the American College of Surgeons. This society catalyzed a quality improvement initiative across the United States and the formation of the Joint Commission on Accreditation of Hospitals. Since that time, those such as Avedis Donabedian and the Institute of Medicine have worked to structure the process of improving both the quality and delivery of health care. Significant advances include the defining of minimum standards for hospital accreditation, 7 pillars of quality in medicine, and the process by which quality in medicine is evaluated. All of these factors have affected current practice more each day. In a field such as spinal surgery, cost and quality measures are continually emphasized and led to large outcome databases to better evaluate outcomes in complex, heterogeneous populations. Going forward, these databases will be instrumental in developing practice patterns and improving spinal surgery outcomes.
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http://dx.doi.org/10.1177/2192568219853529DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6947686PMC
January 2020

Oculomotor neuropathy from an unruptured arteriovenous malformation in the frontal operculum: A case report.

Surg Neurol Int 2019 28;10:128. Epub 2019 Jun 28.

Department of Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, PA, USA.

Background: Cerebral arteriovenous malformations (AVMs) are vascular lesions with a network of dysplastic vessels between an arterial and a venous tree with no intervening capillary bed. They most commonly present with an acute hemorrhage, seizures, or persistent headaches.

Case Description: The authors report the case of a 62-year-old male who presented with diplopia for 5 days. Magnetic resonance imaging and angiography demonstrated a Spetzler-Martin Grade 2 AVM located in the right frontal operculum with deep drainage into the basal vein of Rosenthal causing ipsilateral oculomotor neuropathy. The patient underwent staged embolizations of the feeding pedicles, which were derived from the internal as well as external carotid circulation. This was followed by a right pterional craniotomy for resection of the AVM. The patient reported complete resolution of the diplopia over 4 weeks with no recurrence at the 6-month follow-up appointment.

Conlusion: AVMs of the brain can present with atypical clinical symptoms that can be caused by the venous drainage pattern not the location. It is important to include vascular imaging studies in the work-up of patients who present with diplopia to rule out an AVM. Early diagnosis and treatment of the AVM can result in complete resolution of the diplopia.
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http://dx.doi.org/10.25259/SNI-260-2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6744769PMC
June 2019

Imaging cellulose synthase motility during primary cell wall synthesis in the grass Brachypodium distachyon.

Sci Rep 2017 11 8;7(1):15111. Epub 2017 Nov 8.

Biology Department, University of Massachusetts, Amherst, MA, 01003, USA.

The mechanism of cellulose synthesis has been studied by characterizing the motility of cellulose synthase complexes tagged with a fluorescent protein; however, this approach has been used exclusively on the hypocotyl of Arabidopsis thaliana. Here we characterize cellulose synthase motility in the model grass, Brachypodium distachyon. We generated lines in which mEGFP is fused N-terminal to BdCESA3 or BdCESA6 and which grew indistinguishably from the wild type (Bd21-3) and had dense fluorescent puncta at or near the plasma membrane. Measured with a particle tracking algorithm, the average speed of GFP-BdCESA3 particles in the mesocotyl was 164 ± 78 nm min (error gives standard deviation [SD], n = 1451 particles). Mean speed in the root appeared similar. For comparison, average speed in the A. thaliana hypocotyl expressing GFP-AtCESA6 was 184 ± 86 nm min (n = 2755). For B. distachyon, we quantified root diameter and elongation rate in response to inhibitors of cellulose (dichlorobenylnitrile; DCB), microtubules (oryzalin), or actin (latrunculin B). Neither oryzalin nor latrunculin affected the speed of CESA complexes; whereas, DCB reduced average speed by about 50% in B. distachyon and by about 35% in A. thaliana. Evidently, between these species, CESA motility is well conserved.
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http://dx.doi.org/10.1038/s41598-017-14988-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5678151PMC
November 2017

Stromules: Probing Formation and Function.

Plant Physiol 2018 01 2;176(1):128-137. Epub 2017 Nov 2.

Department of Molecular Biology and Genetics, Cornell University, Biotechnology Building, Ithaca, New York 14853.

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http://dx.doi.org/10.1104/pp.17.01287DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761818PMC
January 2018

Stromules: Probing Formation and Function.

Plant Physiol 2018 01 2;176(1):128-137. Epub 2017 Nov 2.

Department of Molecular Biology and Genetics, Cornell University, Biotechnology Building, Ithaca, New York 14853.

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http://dx.doi.org/10.1104/pp.17.01287DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761818PMC
January 2018

An Organelle RNA Recognition Motif Protein Is Required for Photosystem II Subunit Transcript Editing.

Plant Physiol 2017 04 17;173(4):2278-2293. Epub 2017 Feb 17.

Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan 49008-5410 (J.B.H., A.T.K., M.K.L., R.L.W., Y.L.); and

Loss-of-function mutations in ORGANELLE RNA RECOGNITION MOTIF PROTEIN6 (ORRM6) result in the near absence of RNA editing of -C77 and the reduction in -C794 editing in Arabidopsis (). The mutants have decreased levels of photosystem II (PSII) proteins, especially PsbF, lower PSII activity, pale green pigmentation, smaller leaf and plant sizes, and retarded growth. Stable expression of rescues the editing defects and mutant phenotype. Unlike ORRM1, the other known ORRM plastid editing factor, ORRM6, does not contain RNA editing interacting protein/multiple organellar RNA editing factor (RIP/MORF) boxes, which are required for ORRM1 to interact with site-specific pentatricopeptide repeat protein editing factors. ORRM6 interacts with RIP1/MORF8, RIP2/MORF2, and RIP9/MORF9, known components of RNA editosomes. While some plastid RRM proteins are involved in other forms of RNA processing and translation, the primary function of ORRM6 is evidently to mediate -C77 editing, like the essential site-specific pentatricopeptide repeat protein LOW PSII ACCUMULATION66. Stable expression in the mutants of a nucleus-encoded, plastid-targeted PsbF protein from a gene carrying a T at nucleotide 77 significantly increases leaf and plant sizes, chlorophyll content, and PSII activity. These transformants demonstrate that plastid RNA editing can be bypassed through the expression of nucleus-encoded, edited forms of plastid genes.
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http://dx.doi.org/10.1104/pp.16.01623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5373051PMC
April 2017
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