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1.
Mol Cell ; 83(4): 574-588.e11, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36731470

RESUMO

Most eukaryotic promoter regions are divergently transcribed. As the RNA polymerase II pre-initiation complex (PIC) is intrinsically asymmetric and responsible for transcription in a single direction, it is unknown how divergent transcription arises. Here, the Saccharomyces cerevisiae Mediator complexed with a PIC (Med-PIC) was assembled on a divergent promoter and analyzed by cryoelectron microscopy. The structure reveals two distinct Med-PICs forming a dimer through the Mediator tail module, induced by a homodimeric activator protein localized near the dimerization interface. The tail dimer is associated with ∼80-bp upstream DNA, such that two flanking core promoter regions are positioned and oriented in a suitable form for PIC assembly in opposite directions. Also, cryoelectron tomography visualized the progress of the PIC assembly on the two core promoter regions, providing direct evidence for the role of the Med-PIC dimer in divergent transcription.


Assuntos
RNA Polimerase II , Proteínas de Saccharomyces cerevisiae , RNA Polimerase II/metabolismo , Microscopia Crioeletrônica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Regiões Promotoras Genéticas , Transcrição Gênica , Complexo Mediador/genética , Iniciação da Transcrição Genética
2.
RNA ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942480

RESUMO

SARS-CoV-2, the causative virus of the COVID-19 pandemic, follows SARS and MERS as recent zoonotic coronaviruses causing severe respiratory illness and death in humans. The recurrent impact of zoonotic coronaviruses demands a better understanding of their fundamental molecular biochemistry. Nucleoside modifications, which modulate many steps of the RNA lifecycle, have been found in SARS-CoV-2 RNA, although whether they confer a pro- or anti-viral effect is unknown. Regardless, the viral RNA-dependent RNA polymerase will encounter these modifications as it transcribes through the viral genomic RNA. We investigated the functional consequences of nucleoside modification on the pre-steady state kinetics of SARS-CoV-2 RNA-dependent RNA transcription using an in vitro reconstituted transcription system with modified RNA templates. Our findings show that N6-methyladenosine and 2'O-methyladenosine modifications slow the rate of viral transcription at magnitudes specific to each modification, which has the potential to impact SARS-CoV-2 genome maintenance.

3.
Retina ; 42(11): 2229-2235, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31815876

RESUMO

PURPOSE: Controversy exists regarding the best method for biopsy of uveal melanoma. We describe our transvitreal technique and evaluate the safety of this technique as well as the efficacy for obtaining sample for prognostic genetic profiling. METHODS: Description of surgical technique and retrospective case series. Medical records for uveal melanoma patients who underwent transvitreal biopsy using our described technique were analyzed for tumor size, location, primary treatment, method of biopsy, and any complications thereof. Characteristics of tumors that underwent transvitreal biopsy were noted including tumor size, location, or presence of subretinal fluid, to see whether these affected surgeon preference for biopsy modality. A cohort of contemporaneous uveal melanoma patients who underwent biopsy through a transscleral technique served as a comparator group for these patient, tumor, and complication factors. RESULTS: A total of 27 patients aged 27.2 to 88.6 years (mean 64.8) underwent transvitreal biopsy using our described technique between 2013 and 2016. There were 15 small, 10 medium, and 2 large tumors at diagnosis with the majority (n = 17) posterior to the equator. Intraoperative complications included a clot or small trickle of blood at the biopsy site in 20 (74.1%) of patients, small localized subretinal hemorrhage in 8 (29.6%), small vitreous hemorrhage in 4 (14.8%), and small transient choroidal detachments in 1 patient (3.6%). When subretinal hemorrhage occurred, it was almost always into a pre-existing pocket of subretinal fluid ( P = 0.0093). However, the presence of subretinal fluid was not associated with the decision to proceed with any biopsy ( P = 0.36) or transvitreal biopsy specifically ( P = 1.00). By 3 months, subretinal and/or vitreous hemorrhage resolved in essentially all cases. There were no cases of iatrogenic retinal detachment or extraocular tumor spread over a mean follow-up of 41.7 (range: 20-62.1) months. Adequate tissue for gene expression profiling was obtained from each biopsy. The comparator group of patients undergoing transscleral biopsy including 21 uveal melanomas in 20 patients (one eye had two melanomas). Transvitreal biopsies were more common in patients with small (n = 15; P < 0.0001), posterior (n = 17; P < 0.0001) tumors, compared with patients who underwent transscleral biopsy during the same period. CONCLUSION: This technique can be used for small or posterior tumors or for small anterior tumors where a transscleral approach would risk tumor perforation. Complications were minor, transient, and self-limited. Biopsy yields for molecular prognosis were adequate in all cases. The presence of subretinal fluid may be considered a relative contraindication because it may lead to subretinal hemorrhage in the fluid pocket but did not dissuade us from using this transvitreal technique for patients who would benefit from it.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Hemorragia Vítrea , Estudos Retrospectivos , Biópsia por Agulha Fina/métodos , Neoplasias Uveais/genética , Neoplasias Uveais/cirurgia , Neoplasias Uveais/patologia , Melanoma/diagnóstico , Biópsia
4.
Am J Physiol Heart Circ Physiol ; 321(5): H976-H984, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34559578

RESUMO

Heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF) often arises from a prolonged LV pressure overload (LVPO) and accompanied by abnormal extracellular matrix (ECM) accumulation. The E3 ubiquitin ligase WWP1 is a fundamental determinant ECM turnover. We tested the hypothesis that genetic ablation of Wwp1 would alter the progression of LVPO-induced HFpEF. LV echocardiography in mice with global Wwp1 deletion (n = 23; Wwp1-/-) was performed at 12 wk of age (baseline) and then at 2 and 4 wk following LVPO (transverse aortic banding) or surgery without LVPO induction. Age-matched wild-type mice (Wwp1+/+; n = 23) underwent identical protocols. LV EF remained constant and unchanged with LVPO and LV mass increased in both groups but was lower in the Wwp1-/- mice. With LVPO, the E/A ratio, an index of LV filling, was 3.97 ± 0.46 in Wwp1+/+ but was 1.73 ± 0.19 in the Wwp1-/- group (P < 0.05). At the transcriptional level, mRNA for fibrillar collagens (types I and III) decreased by approximately 50% in Wwp1-/- compared with the Wwp1+/+ group at 4 wk post-LVPO (P < 0.05) and was paralleled by a similar difference in LV fibrillar collagen content as measured by histochemistry. Moreover, mRNA levels for determinants favoring ECM accumulation, such as transforming growth factor (TGF), increased with LVPO, but were lower in the Wwp1-/- group. The absence of Wwp1 reduced the development of left ventricular hypertrophy and subsequent progression to HFpEF. Modulating the WWP1 pathway could be a therapeutic target to alter the natural history of HFpEF.NEW & NOTEWORTHY Heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF) often arises from a prolonged LV pressure overload (LVPO) and is accompanied by abnormal extracellular matrix (ECM) accumulation. It is now recognized that the ECM is a dynamic entity that is regulated at multiple post-transcriptional levels, including the E3 ubiquitin ligases, such as WWP1. In the present study, WWP1 deletion in the context of an LVPO stimulus reduced functional indices of HFpEF progression and determinants of ECM remodeling.


Assuntos
Insuficiência Cardíaca/enzimologia , Ventrículos do Coração/enzimologia , Hipertrofia Ventricular Esquerda/enzimologia , Ubiquitina-Proteína Ligases/deficiência , Disfunção Ventricular Esquerda/enzimologia , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Aorta/fisiopatologia , Aorta/cirurgia , Diástole , Modelos Animais de Doenças , Progressão da Doença , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Colágenos Fibrilares/genética , Colágenos Fibrilares/metabolismo , Deleção de Genes , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Tempo , Ubiquitina-Proteína Ligases/genética , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia
5.
Am J Physiol Heart Circ Physiol ; 319(4): H765-H774, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32822210

RESUMO

Ubiquitylation is a key event that regulates protein turnover, and induction of the ubiquitin ligase E3 WWP1 has been associated with age. Left ventricular hypertrophy (LVH) commonly occurs as a function of age and can cause heart failure (HF) with a preserved ejection fraction (EF; HFpEF). We hypothesized that overexpression (O/E) of WWP1 in the heart would cause LVH as well as functional and structural changes consistent with the aging HFpEF phenotype. Global WWP1 O/E was achieved in mice (n = 11) and echocardiography (40 MHz) performed to measure LV mass, EF, Doppler velocities (early E, late/atrial A), myocardial relaxation (E'), and isovolumetric relaxation time (IVRT) at 4, 6, and 8 wk. Age-matched wild-type animals (n = 15) were included as referent controls. LV EF was identical (60 ± 1 vs. 60 ± 1%, P > 0.90) with no difference in LV mass (67 ± 3 vs. 75 ± 5, P > 0.25) at 4 wk. However, at 8 wk of age, LV mass increased over twofold, E/A fell (impaired passive filling), and E/E' was lower and IVRT prolonged (impaired LV relaxation) - all P < 0.05. Collagen percent area increased by over twofold and fibrillar collagen expression (RT-PCR) over 1.5-fold (P < 0.05) with WWP1 O/E. WWP1 with an anti-WWP1 antibody could be identified in isolated cardiac fibroblasts, with WWP1 increased over twofold in O/E fibroblasts (P < 0.05). Inducing WWP1 expression caused LVH and preserved systolic function but impaired diastolic dysfunction, consistent with the HFpEF phenotype. Targeting the WWP1 pathway may be a novel therapeutic target for this intractable form of HF associated with aging.NEW & NOTEWORTHY Heart failure (HF) with a preserved ejection fraction (HFpEF) is a growing cause of HF and commonly afflicts the elderly. Milestones for HFpEF include diastolic dysfunction and an abnormal extracelluar matrix (ECM). The ubiquitin ligases, such as WWP1, change with aging and regulate critical protein turnover/stability processes, such as the ECM. The present study demonstrated that induction of WWP1 in mice induced LV hypertrophy, diastolic dysfunction, and ECM accumulation, consistent with the HFpEF phenotype, and thus may identify a new therapeutic pathway.


Assuntos
Matriz Extracelular/enzimologia , Insuficiência Cardíaca/enzimologia , Hipertrofia Ventricular Esquerda/enzimologia , Miocárdio/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Disfunção Ventricular Esquerda/enzimologia , Função Ventricular Esquerda , Remodelação Ventricular , Fatores Etários , Animais , Células Cultivadas , Diástole , Modelos Animais de Doenças , Feminino , Fibroblastos/enzimologia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Proteólise , Volume Sistólico , Ubiquitina-Proteína Ligases/genética , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
6.
Vet Pathol ; 56(5): 725-731, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31113293

RESUMO

Digital microscopy (DM) has been employed for primary diagnosis in human medicine and for research and teaching applications in veterinary medicine, but there are few veterinary DM validation studies. Region of interest (ROI) digital cytology is a subset of DM that uses image-stitching software to create a low-magnification image of a slide, then selected ROI at higher magnification, and stitches the images into a relatively small file of the embedded magnifications. This study evaluated the concordance of ROI-DM compared to traditional light microscopy (LM) between 2 blinded clinical pathologists. Sixty canine and feline cytology samples from a variety of anatomic sites, including 31 cases of malignant neoplasia, 15 cases of hyperplastic or benign neoplastic lesions, and 14 infectious/inflammatory lesions, were evaluated. Two separate nonblinded adjudicating clinical pathologists evaluated the reports and diagnoses and scored each paired case as fully concordant, partially concordant, or discordant. The average overall concordance (full and partial concordance) for both pathologists was 92%. Full concordance was significantly higher for malignant lesions than benign. For the 40 neoplastic lesions, ROI-DM and LM agreed on general category of tumor type in 78 of 80 cases (98%). ROI-DM cytology showed robust concordance with the current gold standard of LM cytology and is potentially a viable alternative to current LM cytology techniques.


Assuntos
Doenças do Gato/patologia , Técnicas Citológicas/métodos , Doenças do Cão/patologia , Processamento de Imagem Assistida por Computador , Microscopia/métodos , Animais , Doenças do Gato/diagnóstico por imagem , Gatos , Doenças Transmissíveis/diagnóstico por imagem , Doenças Transmissíveis/patologia , Doenças Transmissíveis/veterinária , Doenças do Cão/diagnóstico por imagem , Cães , Inflamação/diagnóstico por imagem , Inflamação/patologia , Inflamação/veterinária , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neoplasias/veterinária , Software
7.
Retina ; 38(4): 764-772, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28267112

RESUMO

PURPOSE: To report reactivation rate after bevacizumab treatment for retinopathy of prematurity (ROP) in eyes with classic ROP (CROP) versus aggressive posterior ROP (APROP) and to report peripheral fluorescein angiography findings in these eyes. METHODS: Retrospective chart review was conducted on consecutive infants treated with bevacizumab for ROP, followed by fluorescein angiography and prophylactic laser to persistent avascular retina. RESULTS: Sixty-four eyes of 33 patients were included. Mean gestational age was 25 weeks with mean birth weight of 674 g. Mean follow-up was 125 weeks post-menstrual age (PMA). Reactivation requiring treatment after initial bevacizumab was more common in eyes with APROP (8/16) than with CROP (2/48; P < 0.0001). At mean 73 weeks PMA, eyes with APROP had more avascular retina (mean 4.4 disk diameters vs. 2.6 disk diameters; P = 0.0004) and higher percentage of leakage (11/11 eyes vs. 22/38 eyes; P = 0.01) on fluorescein angiography than in eyes with CROP. Unfavorable outcome occurred in 1 of 16 eyes with APROP and in no eyes with CROP. No eye that underwent prophylactic laser after bevacizumab had a poor structural outcome. CONCLUSION: In our study, bevacizumab-treated eyes with APROP have a higher likelihood of recurrence and larger area of persistent nonperfusion than in eyes with CROP. Treatment of ROP with bevacizumab followed by prophylactic laser has a low rate of unfavorable structural outcome.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Angiofluoresceinografia , Fotocoagulação a Laser , Retinopatia da Prematuridade/terapia , Feminino , Humanos , Lactente , Injeções Intravítreas , Masculino , Recidiva , Retinopatia da Prematuridade/diagnóstico por imagem , Retinopatia da Prematuridade/patologia , Estudos Retrospectivos
8.
Neurosurg Focus ; 45(VideoSuppl1): V4, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29963914

RESUMO

Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is a well-accepted procedure with good outcomes. Robotics has the potential to augment these outcomes. This video demonstrates and discusses how surgeons can implement the use of a robotic device in an MIS TLIF workflow. The planning software and robotic arm guidance allow the surgeon to use intraoperative CT to guide the placement of pedicle screws in an MIS TLIF with optimal trajectory and decreased radiation. As robotic technology continues to improve, developing safe workflows that integrate robotics with currently well-established techniques should improve patient outcomes. The video can be found here: https://youtu.be/rJWOa6XVLW0 .


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Fusão Vertebral/métodos , Fluxo de Trabalho , Parafusos Ósseos , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Robóticos/instrumentação , Fusão Vertebral/instrumentação
9.
J Spinal Disord Tech ; 27(3): 185-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24945297

RESUMO

STUDY DESIGN: Case report and review of the literature. OBJECTIVE: The aim of this study was to describe a novel approach for anterior cervical fixation, which uses cement augmentation in a patient with osteoporosis. SUMMARY OF BACKGROUND DATA: Osteoporotic bone presents a challenge for the treating spine surgeon, and techniques to overcome the difficulty of cervical spine fixation in these patients are lacking. METHODS: A 75-year-old woman with osteoporosis presented with cervical myelopathy and was found to have multiple-level cervical stenosis and C3-4 degenerative instability. The patient underwent anterior cervical discectomy fusion and plating from C3-7, with vertebroplasty polymethylmethacrylate augmentation through the screw pilot holes. Because of the patient's grossly soft bone, she also underwent postoperative halo placement. RESULTS: No cement extravasation was observed. The halo was removed after 3 months. At 6 months follow-up, the patient had full resolution of her myelopathy. Imaging showed the cervical interbody fusions to be healed at all levels, with no screw pullout or graft subsidence. CONCLUSIONS: This represents the first comprehensive description of successful cement augmentation during anterior cervical discectomy fusion and plating in a patient with osteoporosis, accomplishing both an increase in screw pullout strength and a decreased likelihood of graft subsidence. With further study, this technique may represent a viable treatment option in patients with osteoporosis requiring cervical decompression and fusion.


Assuntos
Vértebras Cervicais/cirurgia , Discotomia/métodos , Osteoporose/cirurgia , Polimetil Metacrilato/uso terapêutico , Fusão Vertebral/métodos , Idoso , Cimentos Ósseos/uso terapêutico , Parafusos Ósseos , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Radiografia , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/cirurgia
10.
J Orthop Case Rep ; 14(5): 72-77, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38784881

RESUMO

Introduction: The Bosworth fracture-dislocation is a rare injury originally described as an irreducible dislocation of a distal fibula fracture where the proximal fibular fragment becomes incarcerated behind the distal tibia. There have since been a few cases described of an intact distal fibula with dislocation and similar difficulties in closed reduction attempts, typically seen with associated injuries to the ankle or proximal fibula. Regardless of the specific fracture or dislocation pattern, closed reduction attempts have consistently failed in the significant majority of these cases, which can lead to complications including soft-tissue compromise, severe post-traumatic arthritis, compartment syndrome, avascular necrosis of the talus, and neurovascular compromise. There is only one case in recent literature that describes an isolated distal fibula dislocation without associated fractures or dislocations of the lower extremity; however, it required an open reduction. Cases where a closed reduction was successful to achieve an anatomic reduction of a Bosworth-type injury are exceedingly rare. Case Report: We present a rare case of a purely ligamentous, isolated distal fibula dislocation in a 21-year-old male who underwent a successful closed reduction upon initial presentation and later underwent surgical fixation with a syndesmosis repair system. We describe the technique used for a successful closed reduction for this injury and present a 1-year follow-up with excellent outcomes. Conclusion: This is the only known case report of a successful closed reduction in an isolated distal fibula dislocation, as well as demonstrating a minimally invasive technique for definitive treatment with a syndesmosis repair system. Accurate diagnosis, early treatment, and anatomic reduction are imperative for good clinical outcomes and reducing complications for Bosworth injuries. This technique may improve the rates of successful closed reductions of Bosworth injuries upon initial presentation, leading to decreased complications and improved patient outcomes.

11.
J Neurosurg ; 140(1): 282-290, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37439489

RESUMO

OBJECTIVE: Women neurosurgeons (WNs) continue to remain a minority in the specialty despite significant initiatives to increase their representation. One domain less explored is the regional distribution of WNs, facilitated by the hiring practices of neurosurgical departments across the US. In this analysis, the authors coupled the stated practice location of WNs with regional geospatial data to identify hot spots and cold spots of prevalence and examined regional predictors of increases and decreases in WNs over time. METHODS: The authors examined the National Provider Identifier (NPI) numbers of all neurosurgeons obtained via the National Plan and Provider Enumeration System (NPPES), identifying the percentage of WNs in each county for which data were appended with data from the US Census Bureau. Change in WN rates was identified by calculating a regression slope for all years included (2015-2022). Hot spots and cold spots of WNs were identified through Moran's clustering analysis. Population and surgeon features were compared for hot spots and cold spots. RESULTS: WNs constituted 10.73% of all currently active neurosurgical NPIs, which has increased from 2015 (8.81%). Three hot spots were found-including the Middle Atlantic and Pacific divisions-that contrasted with scattered cold spots throughout the East Central regions that included Memphis as a major city. Although relatively rapidly growing, hot spots had significant gender inequality, with a median WN percentage of 11.38% and a median of 0.61 WNs added to each respective county per year. CONCLUSIONS: The authors analyzed the prevalence of WNs by using aggregated data from the NPPES and US Census Bureau. The authors also show regional hot spots of WNs and that the establishment of WNs in a region is a predictor of additional WNs entering the region. These data suggest that female neurosurgical mentorship and representation may be a major driver of acceptance and further gender diversity in a given region.


Assuntos
Neurocirurgia , Humanos , Feminino , Neurocirurgiões , Procedimentos Neurocirúrgicos , Análise por Conglomerados , Prevalência
12.
J Neurosurg ; 140(4): 1091-1101, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37890179

RESUMO

OBJECTIVE: Industry partnerships help advance the field of neurosurgery. Given the nature of the field and its close relationship with innovation, neurosurgeons frequently partner with the medical device industry to advance technology and improve outcomes. However, this can create important ethical concerns for patients. In this paper, the authors sought to comprehensively study how physician payments from medical device companies have changed and what geographic parameters influence the trends observed over the years. METHODS: The authors queried and merged several large databases, including Medicare and Medicaid provider usage data and databases from the Open Payments Program, National Plan and Provider Enumeration System, and US Census Bureau. Geospatial analysis was performed using Moran's I and II clustering. Univariate and multivariable analyses were performed using the Mann-Whitney U-test and geospatially weighted multivariable regression for hot spot and cold spot membership. RESULTS: Data for 952 counties across the continental United States were analyzed. Ninety-seven counties constituted geographic hot spots. These hot spots were primarily concentrated in Florida, the New York-Pennsylvania region, central Colorado, and southwestern United States. Independent predictors of hot spot membership included greater unemployment rates, the percentage of White patients, the presence of mobile homes, and the percentage of county Hispanic and Black populations. Company-based differences were examined. The vast majority of Medtronic's payments were in the form of royalties and licensing (86.6%). Royalties and licensing accounted for the majority of payments for DePuy (69.4%), Globus Medical (62%), and NuVasive (77.1%). In contrast, other companies, such as Boston Scientific, opted to pay physicians in the form of ownership and investment interests (42.1%). The impact of the COVID-19 pandemic was also assessed. During the onset of the pandemic in 2020, physician payments fell or remained the same across all regions with the exception of the South Atlantic region. However, it was observed that nearly all regions rebounded, with stark elevations in physician payments immediately in 2021. CONCLUSIONS: This analysis demonstrates that there are national hot spots and cold spots of physician payments, and offers some social, economic, and company-dependent predictors that may influence the magnitude of payments. Further analysis is needed to better understand this clinical-commercial partnership in healthcare, specifically within neurosurgical practice.


Assuntos
Neurocirurgia , Médicos , Idoso , Humanos , Estados Unidos , Medicare , Pandemias , Neurocirurgiões , Bases de Dados Factuais
13.
J Neurosurg Spine ; 40(1): 107-114, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37877935

RESUMO

OBJECTIVE: The American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) Joint Spine Section awards highlight outstanding abstracts submitted to the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves by trainees interested in spine surgery, although the academic trajectory of awardees has not been studied. The aim of this study was to assess the academic career progression of prior recipients of the Journalistic and Academic Neurosurgical Excellence (JANE), Mayfield, and Kuntz research awards. METHODS: Prior JANE, Mayfield, and Kuntz award recipients were identified using awardee records accrued between 1984 and February 2022. Awardee sex, country of residence, specialty, subspecialty focus, and current academic appointment status (if applicable) were searched online. Awardee h-indices and number of peer-reviewed publications were assessed via Google Scholar profiles (or Scopus if unavailable) and PubMed, respectively. Receipt of federal research funding as principal investigator (PI) was determined using the websites of the National Institutes of Health, the National Science Foundation, and the Department of Defense Congressionally Directed Medical Research Programs. The abstract-to-publication rate was assessed. RESULTS: A total of 7 JANE awards, 57 Mayfield awards, and 149 Kuntz awards were identified. Of the JANE awardees, all recipients were male. Of the 4 unique JANE awardees who completed training, 2 (50.0%) held academic appointments at the time of the study. All of the JANE abstracts were published in peer-reviewed journals. The mean h-index of all JANE awardees was 28 and the mean number of publications was 126. None of the awardees have received federal research funding. Of the Mayfield awards, 98.2% were awarded to males. Of the 43 unique Mayfield awardees who completed training, 20 (46.5%) held faculty appointments at academic medical centers. All of the Mayfield abstracts since 2011 were published in peer-reviewed journals. The mean h-index of all Mayfield awardees was 26 and the mean number of publications was 82. Five Mayfield awardees received National Institutes of Health funding as PI, and 7 awardees received Department of Defense funding as PI. Of the Kuntz awards, 95.3% were awarded to males. Most awards were given to current residents and fellows (46.3%). Of the 55 unique Kuntz awardees who completed training, 31 (56.4%) held faculty appointments at academic medical centers. The abstract-to-publication rate of the total Kuntz abstracts was 70.5%. The mean h-index of all Kuntz awardees was 15 and the mean number of publications was 58. Five Kuntz awardees (3.4%) received federal research funding as PI. CONCLUSIONS: Many recipients of the JANE, Mayfield, and Kuntz Joint Spine Section awards have successfully translated award abstracts into peer-reviewed publications. Furthermore, approximately one-third of the awardees are active in academic neurosurgery, with some having secured federal research funding.


Assuntos
Distinções e Prêmios , Pesquisa Biomédica , Neurocirurgia , Humanos , Masculino , Estados Unidos , Feminino , Neurocirurgiões , Procedimentos Neurocirúrgicos
14.
J Neurosurg ; 140(2): 560-569, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37877969

RESUMO

OBJECTIVE: Sport-related concussions (SRCs) can cause significant neurological symptoms, and approximately 10%-15% of athletes with SRC experience a prolonged recovery. Given the lack of visible injury on brain imaging and their varied presentations, concussions can be difficult to diagnose. A variety of tests and examination methods have been used to elicit a concussion diagnosis; however, the sensitivity and specificity of these tests are variable. The authors performed a systematic review and meta-analysis to evaluate the sensitivity and specificity of standardized tests and visible signs like balance and vision changes in the diagnosis of SRC. METHODS: A PRISMA-adherent systematic review of concussion diagnostic examinations was performed using the PubMed, MEDLINE, Scopus, Cochrane, Web of Science, and Google Scholar databases on December 1, 2022. Search terms included "concussion," "traumatic brain injury," "diagnosis," "sensitivity," and "specificity." Each method of examination was categorized into larger group-based symptomatologic presentations or standardized tools. The primary outcome was the diagnosis of concussion. Pooled specificity and sensitivity for each method were calculated using a meta-analysis of proportion and were hierarchically ranked using P-scores calculated from a diagnostic frequentist network meta-analysis. RESULTS: Thirty full-length articles were identified for inclusion, 13 of which evaluated grouped symptomology examinations (balance and overall clinical presentation) and 17 of which evaluated established formalized tools (ImPACT, King-Devick [K-D] Test, Sport Concussion Assessment Tool [SCAT]). The pooled specificity of the examination methods differed minimally (0.8-0.85), whereas the sensitivity varied to a larger degree (0.5-0.88). In a random effects model, the SCAT had the greatest diagnostic yield (diagnostic OR 31.65, 95% CI 11.06-90.57). Additionally, P-score hierarchical ranking revealed SCAT as having the greatest diagnostic utility (p = 0.9733), followed sequentially by ImPACT, clinical presentation, K-D, and balance. CONCLUSIONS: In deciphering which concussion symptom-focused examinations and standardized tools are most accurate in making a concussion diagnosis, the authors found that the SCAT examination has the greatest diagnostic yield, followed by ImPACT, clinical presentation, and K-D, which have comparable value for diagnosis. Given the indirect nature of this analysis, however, further comparative studies are needed to validate the findings.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes , Humanos , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/complicações , Concussão Encefálica/diagnóstico , Sensibilidade e Especificidade , Atletas
15.
J Neurosurg Spine ; : 1-7, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905710

RESUMO

OBJECTIVE: The mini-open lateral retropleural (MO-LRP) approach is an effective option for surgically treating thoracic disc herniations, but the approach raises concerns for pneumothorax (PTX). However, chest tube placement causes insertion site tenderness, necessitates consultation services, increases radiation exposure (requires multiple radiographs), delays the progression of care, and increases narcotic requirements. This study examined the incidence of radiographic and clinically significant PTX and hemothorax (HTX) after the MO-LRP approach, without the placement of a prophylactic chest tube, for thoracic disc herniation. METHODS: This study was a single-institution retrospective evaluation of consecutive cases from 2017 to 2022. Electronic medical records were reviewed, including postoperative chest radiographs, radiology and operative reports, and postoperative notes. The presence of PTX or HTX was determined on chest radiographs obtained in all patients immediately after surgery, with interval radiographs if either was present. The size was categorized as large (≥ 3 cm) or small (< 3 cm) based on guidelines of the American College of Chest Physicians. PTX or HTX was considered clinically significant if it required intervention. RESULTS: Thirty patients underwent thoracic discectomy via the MO-LRP approach. All patients were included. Twenty patients were men (67%), and 10 (33%) were women. The patients ranged in age from 25 to 74 years. The most commonly treated level was T11-12 (n = 11, 37%). Intraoperative violation of parietal pleura occurred in 5 patients (17%). No patient had prophylactic chest tube placement. Fifteen patients (50%) had PTX on postoperative chest radiographs; 2 patients had large PTXs, and 13 had small PTXs. Both patients with large PTXs had expansion on repeat radiographs and were treated with chest tube insertion. Of the 13 patients with a small PTX, 1 required 100% oxygen using a nonrebreather mask; the remainder were asymptomatic. One patient, who had no abnormal findings on the immediate postoperative chest radiograph, developed an incidental HTX on postoperative day 6 and was treated with chest tube insertion. Thus, 3 patients (10%) required a chest tube: 2 for expanding PTX and 1 for delayed HTX. CONCLUSIONS: Most patients who undergo thoracic discectomy via the MO-LRP approach do not develop clinically significant PTX or HTX. PTX and HTX in this patient population should be treated with a chest tube only when there are postoperative clinical and radiographic indications.

16.
J Vasc Interv Radiol ; 24(2): 214-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23182939

RESUMO

PURPOSE: To evaluate expansion of image-guided interventional cryoablation techniques usually employed for pain management to address the feasibility, safety, and efficacy of treatment for a urologic condition with otherwise limited treatment options, premature ejaculation (PE). MATERIALS AND METHODS: Prospective institutional review board approval was obtained, and 24 subjects with PE were enrolled. All patients underwent unilateral percutaneous computed tomography-guided cryoablation of the dorsal penile nerve (DPN). Postprocedural intravaginal ejaculatory latency times (IELTs) and PE Profile (PEP) results served as outcome variables. In addition, subjects were asked whether they would have the procedure done again based on their experience at the 180- and 360-day marks. RESULTS: The technical success rate was 100%. Baseline average IELT was 54.7 seconds ± 7.8 (n = 24), which increased to a maximum of 256 seconds ± 104 (n = 11; P = .241) by day 7 and decreased to 182.5 seconds ± 87.8 (n = 6; P = .0342) by day 90. The mean IELT remained at 182.5 seconds ± 27.6 at day 180 (n = 23; P<.0001) and decreased to 140.9 seconds ± 83.6 by 1 year (n = 22; P<.001). PEP scores improved overall, IELTs significantly improved at 180 and 360 days, and 83% of subjects reported that they would undergo the procedure again if given the same opportunity. There were no procedure-related complications. CONCLUSIONS: CT-guided percutaneous unilateral cryoablation of the DPN is a feasible, safe, single-day outpatient procedure for the treatment of symptomatic PE.


Assuntos
Criocirurgia/métodos , Denervação/métodos , Pênis/inervação , Pênis/cirurgia , Ejaculação Precoce/cirurgia , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Ejaculação Precoce/diagnóstico por imagem , Resultado do Tratamento
17.
Vet Radiol Ultrasound ; 54(6): 638-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23763478

RESUMO

Peritoneal, mesenteric, and omental diseases are important causes of morbidity and mortality in humans and animals, although information in the veterinary literature is limited. The purposes of this retrospective study were to determine whether objectively applied ultrasound interpretive criteria are statistically useful in differentiating among cytologically defined normal, inflammatory, and neoplastic peritoneal conditions in dogs and cats. A second goal was to determine the cytologically interpretable yield on ultrasound-guided, fine-needle sampling of peritoneal, mesenteric, or omental structures. Sonographic criteria agreed upon by the authors were retrospectively and independently applied by two radiologists to the available ultrasound images without knowledge of the cytologic diagnosis and statistically compared to the ultrasound-guided, fine-needle aspiration cytologic interpretations. A total of 72 dogs and 49 cats with abdominal peritoneal, mesenteric, or omental (peritoneal) surface or effusive disease and 17 dogs and 3 cats with no cytologic evidence of inflammation or neoplasia were included. The optimized, ultrasound criteria-based statistical model created independently for each radiologist yielded an equation-based diagnostic category placement accuracy of 63.2-69.9% across the two involved radiologists. Regional organ-associated masses or nodules as well as aggregated bowel and peritoneal thickening were more associated with peritoneal neoplasia whereas localized, severely complex fluid collections were more associated with inflammatory peritoneal disease. The cytologically interpretable yield for ultrasound-guided fine-needle sampling was 72.3% with no difference between species, making this a worthwhile clinical procedure.


Assuntos
Biópsia por Agulha Fina/veterinária , Doenças do Gato/diagnóstico , Doenças do Cão/diagnóstico , Doenças Peritoneais/veterinária , Peritônio/citologia , Peritônio/diagnóstico por imagem , Ultrassonografia de Intervenção/veterinária , Animais , Doenças do Gato/diagnóstico por imagem , Gatos , Doenças do Cão/diagnóstico por imagem , Cães , Feminino , Inflamação/diagnóstico , Inflamação/diagnóstico por imagem , Inflamação/veterinária , Masculino , Mesentério/citologia , Mesentério/diagnóstico por imagem , Mesentério/patologia , Neoplasias/diagnóstico , Neoplasias/diagnóstico por imagem , Neoplasias/veterinária , Omento/citologia , Omento/diagnóstico por imagem , Omento/patologia , Doenças Peritoneais/diagnóstico , Doenças Peritoneais/diagnóstico por imagem , Peritônio/patologia , Estudos Retrospectivos
18.
HPB (Oxford) ; 15(11): 851-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23458468

RESUMO

BACKGROUND: Surgical resection is the standard treatment for liver metastases, although for the majority of patients this is not possible. Stereotactic body radiotherapy (SBRT) is an alternative local-regional therapy. The purpose of this study was to evaluate the results of SBRT for secondary liver tumours from a combined multicentre database. METHODS: Variables from patients treated with SBRT from four Academic Medical Centres were entered into a common database. Local tumour control and 1-year survival rates were calculated. RESULTS: In total, 153 patients (91 women) 59 ± 8.4 years old with 363 metastatic liver lesions were treated with SBRT. The underlying primary tumour arose from gastrointestinal (GI), retroperitoneal and from extra-abdominal primaries in 56%, 8% and 36% of patients, respectively. Metastases, with a gross tumour volume (GTV) of 138.5 ± 126.8 cm(3) , were treated with a total radiation dose of 37.5 ± 8.2 Gy in 5 ± 3 fractions. The 1-year overall survival was 51% with an overall local control rate of 62% at a mean follow-up of 25.2 ± 5.9 months. A complete tumour response was observed in 32% of patients. Grade 3-5 adverse events were noted in 3% of patients. CONCLUSION: Secondary liver tumours treated with SBRT had a high rate of local control with a low incidence of adverse events.


Assuntos
Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Radiocirurgia/métodos , Adulto , Idoso , Feminino , Humanos , Incidência , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Taxa de Sobrevida/tendências , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
19.
Cureus ; 15(11): e48508, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38073948

RESUMO

Patients with ankylosing spondylitis are at high risk of significant spinal trauma after relatively low-impact events, such as ground-level falls. Because of the osteopenic nature of the disease process, complex spinal fractures are common in these patients. Additionally, patients may sustain rare traumatic complications from these fractures, such as a spinal subdural hematoma (SSDH) or epidural hematoma. Traumatic SSDH is extremely rare, with few cases described in the literature, and cases are typically associated with antiplatelet or anticoagulant use. This study reviews the literature related to traumatic SSDH in patients with ankylosing spondylitis and describes two cases of traumatic SSDH in patients with ankylosing spondylitis without anticoagulation or antiplatelet therapy, which has not previously been reported in the literature.

20.
Am J Surg ; 226(6): 864-867, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37532593

RESUMO

INTRODUCTION: Traumatic brain injury (TBI) results in the death of over 50,000 and the permanent disability of 80,000 individuals annually in the United States. Much of the permanent disability is the result of secondary brain injury from intracranial hypertension (ICH). Pentobarbital coma is often instituted following the failure of osmotic interventions and sedation to control intracranial pressure (ICP). The goal of this study was to evaluate the efficacy of pentobarbital coma with respect to ICP management and long-term functional outcome. METHODS: Traumatic brain injury patients who underwent pentobarbital coma at a level 1 trauma center between 2014 and 2021 were identified. Patient demographics, injury characteristics, Glasgow Coma Scale (GCS) scores, intracranial pressures (ICPs), and outcomes were obtained from the trauma registry as well as inpatient and outpatient medical records. The proportion of ICPs below 20 for each hospitalized patient-day was calculated. The primary outcome measured was GCS score at the last follow-up visit. RESULTS: 25 patients were identified, and the majority were male (n â€‹= â€‹23, 92%) with an average age of 30.0 years â€‹± â€‹12.9 and median injury severity score of 30 (21.5-33.5). ICPs were monitored for all patients with a median of 464 (326-1034) measurements. The average hospital stay was 16.9 days â€‹± â€‹11.5 and intensive care stay was 16.9 â€‹± â€‹10.8 days. 9 (36.0%) patients survived to hospital discharge. Mean follow-up time in months was 36.9 â€‹± â€‹28.0 (min-max 3-80). 7 of the 9 surviving patients presented as GCS 15 on follow-up and the remaining were both GCS 9. Patients presenting at last follow-up with GCS 15 had a significantly higher proportion of controlled ICPs throughout their hospitalization compared to patients who expired or with follow-up GCS <15 (GCS 15: 88% â€‹± â€‹10% vs. GCS <15 or dead: 68% â€‹± â€‹22%, P â€‹= â€‹0.006). A comparison of the daily proportion of controlled ICPs by group revealed negligible differences prior to pentobarbital initiation. Groups diverged nearly immediately upon pentobarbital coma initiation with a higher proportion of controlled ICPs for patients with follow-up GCS of 15. CONCLUSION: Patients that do not have an immediate response to pentobarbital coma therapy for ICH universally had poor outcomes. Alternative therapy or earlier palliation should be considered for such patients. In contrast, patients whose ICPs responded quickly to pentobarbital had excellent long-term outcomes.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Hipertensão Intracraniana , Humanos , Masculino , Feminino , Adulto , Coma/complicações , Pentobarbital/uso terapêutico , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Escala de Coma de Glasgow , Hipertensão Intracraniana/etiologia , Hipertensão Intracraniana/complicações , Pressão Intracraniana
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