JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Asymmetry of Habitual 24-Hour Intraocular Pressure Rhythm in Glaucoma Patients.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-18-2014
Show Abstract
Hide Abstract
To examine the strength of association between 24-hour rhythms of habitual IOP in the paired eyes of healthy individuals and glaucoma patients.
Related JoVE Video
Retroperitoneal oblique corridor to the L2-S1 intervertebral discs in the lateral position: an anatomic study.
J Neurosurg Spine
PUBLISHED: 09-12-2014
Show Abstract
Hide Abstract
Object Access to the intervertebral discs from L2-S1 in one surgical position can be challenging. The transpsoas minimally invasive surgical (MIS) approach is preferred by many surgeons, but this approach poses potential risk to neural structures of the lumbar plexus as they course through the psoas. The lumbar plexus and iliac crest often restrict the L4-5 disc access, and the L5-S1 level has not been a viable option from a direct lateral approach. The purpose of the present study was to investigate an MIS oblique corridor to the L2-S1 intervertebral disc space in cadaveric specimens while keeping the specimens in a lateral decubitus position with minimal disruption of the psoas and lumbar plexus. Methods Twenty fresh-frozen full-torso cadaveric specimens were dissected, and an oblique anatomical corridor to access the L2-S1 discs was examined. Measurements were taken in a static state and with mild retraction of the psoas. The access corridor was defined at L2-5 as the left lateral border of the aorta (or iliac artery) and the anterior medial border of the psoas. The L5-S1 corridor of access was defined transversely from the midsagittal line of the inferior endplate of L-5 to the medial border of the left common iliac vessel and vertically to the first vascular structure that crosses midline. Results The mean access corridor diameters in the static state and with mild psoas retraction, respectively, were as follows: at L2-3, 18.60 mm and 25.50 mm; at L3-4, 19.25 mm and 27.05 mm; and at L4-5, 15.00 mm and 24.45 mm. The L5-S1 corridor mean values were 14.75 mm transversely, from midline to the left common iliac vessel and 23.85 mm from the inferior endplate of L-5 cephalad to the first midline vessel. Conclusions The oblique corridor allows access to the L2-S1 discs while keeping the patient in a lateral decubitus position without a break in the table. Minimal psoas retraction without significant tendon disruption allowed for a generous corridor to the disc space. The L5-S1 disc space can be accessed from an oblique angle consistently with gentle retraction of the iliac vessels. This study supports the potential of an MIS oblique retroperitoneal approach to the L2-S1 discs.
Related JoVE Video
Activation of neuronal gene expression by the JMJD3 demethylase is required for postnatal and adult brain neurogenesis.
Cell Rep
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
The epigenetic mechanisms that enable lifelong neurogenesis from neural stem cells (NSCs) in the adult mammalian brain are poorly understood. Here, we show that JMJD3, a histone H3 lysine 27 (H3K27) demethylase, acts as a critical activator of neurogenesis from adult subventricular zone (SVZ) NSCs. JMJD3 is upregulated in neuroblasts, and Jmjd3 deletion targeted to SVZ NSCs in both developing and adult mice impairs neuronal differentiation. JMJD3 regulates neurogenic gene expression via interaction at not only promoter regions but also neurogenic enhancer elements. JMJD3 localizes at neural enhancers genome-wide in embryonic brain, and in SVZ NSCs, JMJD3 regulates the I12b enhancer of Dlx2. In Jmjd3-deleted SVZ cells, I12b remains enriched with H3K27me3 and Dlx2-dependent neurogenesis fails. These findings support a model in which JMJD3 and the poised state of key transcriptional regulatory elements comprise an epigenetic mechanism that enables the activation of neurogenic gene expression in adult NSCs throughout life.
Related JoVE Video
Minimally invasive lateral transpsoas approach to the lumbar spine: pitfalls and complication avoidance.
Neurosurg. Clin. N. Am.
PUBLISHED: 04-08-2014
Show Abstract
Hide Abstract
The lateral transpsoas approach to the lumbar spine has become an increasingly popular method to achieve fusion. Although this approach requires less tissue dissection, a smaller incision, decreased operative time, reduced blood loss and postoperative pain, and shorter hospital stay, it carries the potential for serious neurologic and visceral complications. This article reviews these complications in detail and proposes mechanisms for their avoidance.
Related JoVE Video
Complications associated with posterior approaches in minimally invasive spine decompression.
Neurosurg. Clin. N. Am.
PUBLISHED: 01-25-2014
Show Abstract
Hide Abstract
Posterior approaches for decompression in minimally invasive spine surgery are increasingly used for a wide range of pathology. Surgeons and patients must understand these risks in order to identify, manage, and ideally prevent complications. Technical intraoperative complications, recurrences and reoperations, infections, and medical complications associated with the surgery are considered for common posterior minimally invasive decompression procedures of the cervical and lumbar spine. Methods of possibly avoiding these complications are also discussed. This article then aggregates the relevant data to allow concise understanding of the complications associated with these procedures.
Related JoVE Video
Nicotine gum or patch treatment for smoking cessation and smoking reduction: a multi-centre study in Chinese physicians.
Front Med
PUBLISHED: 01-23-2014
Show Abstract
Hide Abstract
In China, around 23% of physicians (41% male, 3% female) currently smoke. Pharmacotherapy for tobacco dependence is available, but is not widely used in China. The purpose of this study was to estimate the effectiveness and the safety on smoking cessation of nicotine gum and nicotine patch in Chinese healthcare professionals. Three hundred regular smokers motivated to quit were recruited from six hospitals in China. All subjects were accepted nicotine replacement therapy, and they could choose nicotine gum (2 mg or 4 mg, depending on baseline smoking level) or nicotine patch (15 mg/16 h) for 12 weeks, with a 12-week follow-up. Limited behavioural support was provided. At Week 24, the 2-24 weeks continuous abstinence rate (verified by expired carbon monoxide) was 17%, the point prevalence abstinence rate (no smoking since the previous visit) was 35%, and 38% of subjects had continuously reduced their daily cigarette consumption by at least 50% versus baseline. Compliance with treatment was good, particularly with patch. No serious adverse event was reported, and most adverse events were mild or moderate. The most common treatment-related adverse events were gastrointestinal (both gum and patch) and local irritation symptoms. Nicotine patch and gum were well tolerated in Chinese smokers. Abstinence rates were comparable to those previously reported with nicotine replacement therapy, and many smokers who did not quit substantially reduced their cigarette consumption.
Related JoVE Video
Anatomic surgical management of chronic low back pain.
Neuromodulation
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
To review spine surgery management strategies for patients with chronic low back pain (CLBP) that has failed to respond to all nonsurgical treatment options.
Related JoVE Video
Adenovirus-mediated eNOS expression augments liver injury after ischemia/reperfusion in mice.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Hepatic ischemia/reperfusion (l/R) injury continues to be a critical problem. The role of nitric oxide in liver I/R injury is still controversial. This study examines the effect of endothelial nitric oxide synthase (eNOS) over-expression on hepatic function following I/R. Adenovirus expressing human eNOS (Ad-eNOS) was administered by tail vein injection into C57BL/6 mice. Control mice received either adenovirus expressing LacZ or vehicle only. Sixty minutes of total hepatic ischemia was performed 3 days after adenovirus treatment, and mice were sacrificed after 6 or 24 hrs of reperfusion to assess hepatic injury. eNOS over expression caused increased liver injury as evidenced by elevated AST and ALT levels and decreased hepatic ATP content. While necrosis was not pervasive in any group, TUNEL demonstrated significantly increased apoptosis in Ad-eNOS infected livers. Western blotting demonstrated increased levels of protein nitration and upregulation of the pro-apoptotic proteins bax and p53. Our data suggest that over-expression of eNOS is detrimental in the setting of hepatic I/R.
Related JoVE Video
Mitochondrial Uncoupling Protein 2 Induces Cell Cycle Arrest and Necrotic Cell Death.
Metab Syndr Relat Disord
PUBLISHED: 12-09-2013
Show Abstract
Hide Abstract
Abstract Uncoupling protein 2 (UCP2) is a mitochondrial membrane protein that regulates energy metabolism and reactive oxygen species (ROS) production. We generated mouse carboxy- and amino-terminal green fluorescent protein (GFP)-tagged UCP2 constructs to investigate the effect of UCP2 expression on cell proliferation and viability. UCP2-transfected Hepa 1-6 cells did not show reduced cellular adenosine triphosphate (ATP) but showed increased levels of glutathione. Flow cytometry analysis indicated that transfected cells were less proliferative than nontransfected controls, with most cells blocked at the G1 phase. The effect of UCP2 on cell cycle arrest could not be reversed by providing exogenous ATP or oxidant supply, and was not affected by the chemical uncoupler carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP). However, this effect of UCP2 was augmented by treatment with genistein, a tyrosine kinase inhibitor, which by itself did not affect cell proliferation on control hepatocytes. Western blotting analysis revealed decreased expression levels of CDK6 but not CDK2 and D-type cyclins. Examination of cell viability in UCP2-transfected cells with Trypan Blue and Annexin-V staining revealed that UCP2 transfection led to significantly increased cell death. However, characteristics of apoptosis were absent in UCP2-transfected Hepa 1-6 cells, including lack of oligonucleosomal fragmentation (laddering) of chromosomal DNA, release of cytochrome c from mitochondria, and cleavage of caspase-3. In conclusion, our results indicate that UCP2 induces cell cycle arrest at G1 phase and causes nonapoptotic cell death, suggesting that UCP2 may act as a powerful influence on hepatic regeneration and cell death in the steatotic liver.
Related JoVE Video
Anterior-posterior transcranial ultrasound to measure cranial oscillations.
Aviat Space Environ Med
PUBLISHED: 09-13-2013
Show Abstract
Hide Abstract
We aimed to provide information on whether or not the correlation between body tilt and the pulse amplitude of transcranial ultrasonic time-of-flight waveform can be observed in the anterior-posterior skull direction. Also, we asked the question whether or not the skull pulsation can be detected since the cranial bones involved are thicker.
Related JoVE Video
Comparison of Symptomatic Cerebral Spinal Fluid Leak Between Patients Undergoing Minimally Invasive versus Open Lumbar Foraminotomy, Discectomy, or Laminectomy.
World Neurosurg
PUBLISHED: 09-10-2013
Show Abstract
Hide Abstract
Minimally invasive spine surgery (MISS) techniques have similar long-term outcomes compared to open surgery for patients undergoing 1- or 2-level discectomy, foraminotomy, or laminectomy. However, the rate of cerebrospinal fluid (CSF) leaks with both techniques has not been well established in the literature. This study sought to compare the rate and clinical impact of CSF leak in open lumbar foraminotomy, discectomy, or laminectomy with comparable MISS approaches.
Related JoVE Video
CT navigated lateral interbody fusion.
J Clin Neurosci
PUBLISHED: 08-06-2013
Show Abstract
Hide Abstract
Lateral interbody fusion techniques are heavily reliant on fluoroscopy for retractor docking and graft placement, which expose both the patient and surgeon to high doses of radiation. Use of image-guided technologies with CT-based images, however, can eliminate this radiation exposure for the surgeon. We describe the surgical technique of performing lateral lumbar interbody fusion using CT navigation.
Related JoVE Video
Varicella-Zoster-Mediated Radiculitis Reactivation following Cervical Spine Surgery: Case Report and Review of the Literature.
Case Rep Infect Dis
PUBLISHED: 07-26-2013
Show Abstract
Hide Abstract
Varicella-zoster virus and herpes simplex virus types 1 and 2 are neurotropic viruses that can be reactivated after a surgical or stressful intervention. Although such cases are uncommon, consequences can be debilitating, and variable treatment responses merit consideration. We describe a 41-year-old male with a history of varicella-mediated skin eruptions, who presented with continuing right arm pain, burning, and numbness in a C6 dermatomal distribution following a C5-6 anterior cervical discectomy and fusion and epidural steroid injections. The operative course was uncomplicated and he was discharged home on postoperative day 1. Approximately ten days after surgery, the patient presented to the emergency department complaining of severe pain in his right upper extremity and a vesicular rash from his elbow to his second digit. He was started on Acyclovir and discharged home. On outpatient follow-up, his rash had resolved though his pain continued. The patient was started on a neuromodulating agent for chronic pain. This case adds to the limited literature regarding this rare complication, brings attention to the symptoms for proper diagnosis and treatment, and emphasizes the importance of prompt antiviral therapy. We suggest adding a neuromodulating agent to prevent long-term sequelae and resolve acute symptoms.
Related JoVE Video
Optimization of non-periodic plasmonic light-trapping layers for thin-film solar cells.
Nat Commun
PUBLISHED: 06-03-2013
Show Abstract
Hide Abstract
Non-periodic arrangements of nanoscale light scatterers allow for the realization of extremely effective broadband light-trapping layers for solar cells. However, their optimization is challenging given the massive number of degrees of freedom. Brute-force, full-field electromagnetic simulations are computationally too time intensive to identify high-performance solutions in a vast design space. Here we illustrate how a semi-analytical model can be used to quickly identify promising non-periodic spatial arrangements of nanoscale scatterers. This model only requires basic knowledge of the scattering behaviour of a chosen nanostructure and the waveguiding properties of the semiconductor layer in a cell. Due to its simplicity, it provides new intuition into the ideal amount of disorder in high-performance light-trapping layers. Using simulations and experiments, we demonstrate that arrays of nanometallic stripes featuring a limited amount of disorder, for example, following a quasi-periodic or Fibonacci sequence, can substantially enhance solar absorption over perfectly periodic and random arrays.
Related JoVE Video
Twenty-four-hour pattern of intraocular pressure in untreated patients with ocular hypertension.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-21-2013
Show Abstract
Hide Abstract
To characterize the 24-hour pattern of intraocular pressure (IOP) in untreated ocular hypertensive (OHTN) patients.
Related JoVE Video
Atypical presentation of thoracic disc herniation: case series and review of the literature.
Case Rep Orthop
PUBLISHED: 01-17-2013
Show Abstract
Hide Abstract
Modern imaging has revealed that thoracic disc herniation (TDH) has a prevalence of 11-37% in asymptomatic patients. Pain, sensory disturbances, myelopathy, and lower extremity weakness are the most common presenting symptoms, but other atypical extraspinal complaints, such as gastrointestinal or cardiopulmonary discomfort, may be reported. Our objective is to make providers familiar with TDHs atypical symptoms to help avoid potential serious consequences created by a delay in diagnosis. We report the cases of two patients who each presented with atypical extraspinal symptoms secondary to a TDH. One patient presented with a chronic history of nausea, emesis, and chest tightness and MRI showed a large right paramedian disc herniation at T7-8. A second patient reported chronic constipation, buttock and leg burning pain, gait instability, and urinary frequency; an MRI of his thoracic spine demonstrated a central disc herniation at T10-11. TDH can present with vague extraspinal symptoms and unfamiliarity with these symptoms can lead to misdiagnosis with progression of the disease and unnecessary diagnostic tests and medical procedures. Therefore, TDH should be included in the differential diagnosis of patients with negative gastrointestinal, genitourinary, and cardiopulmonary system basic studies.
Related JoVE Video
Postharvest circadian entrainment enhances crop pest resistance and phytochemical cycling.
Curr. Biol.
PUBLISHED: 01-13-2013
Show Abstract
Hide Abstract
The modular design of plants enables individual plant organs to manifest autonomous functions and continue aspects of metabolism, such as respiration, even after separation from the parent plant. Therefore, we hypothesized that harvested vegetables and fruits may retain capacity to perceive and respond to external stimuli. For example, the fitness advantage of plant circadian clock function is recognized; however, whether the clock continues to influence postharvest physiology is unclear. Here we demonstrate that the circadian clock of postharvest cabbage (Brassica oleracea) is entrainable by light-dark cycles and results in enhanced herbivore resistance. In addition, entrainment of Arabidopsis plants and postharvest cabbage causes cyclical accumulation of metabolites that function in plant defense; in edible crops, these metabolites also have potent anticancer properties. Finally, we show that the phenomena of postharvest entrainment and enhanced herbivore resistance are widespread among diverse crops. Therefore, sustained clock entrainment of postharvest crops may be a simple mechanism to promote pest resistance and nutritional value of plant-derived food.
Related JoVE Video
Interspinous device versus laminectomy for lumbar spinal stenosis: a comparative effectiveness study.
Spine J
PUBLISHED: 01-08-2013
Show Abstract
Hide Abstract
Currently no studies directly compare effectiveness between interspinous devices (IDs) and laminectomy in lumbar spinal stenosis (LSS) patients.
Related JoVE Video
Minimally invasive lateral lumbar interbody fusion and transpsoas approach-related morbidity.
Neurosurg Focus
PUBLISHED: 10-04-2011
Show Abstract
Hide Abstract
Recently, the minimally invasive, lateral retroperitoneal, transpsoas approach to the thoracolumbar spinal column has been described by various authors. This is known as the minimally invasive lateral lumbar interbody fusion. The purpose of this study is to elucidate the approach-related morbidity associated with the minimally invasive transpsoas approach to the lumbar spine. To date, there have been only a couple of reports regarding the morbidity of the transpsoas muscle approach.
Related JoVE Video
Complications and outcomes after spinal deformity surgery in the elderly: review of the existing literature and future directions.
Neurosurg Focus
PUBLISHED: 10-04-2011
Show Abstract
Hide Abstract
The elderly population (age > 60 years) is the fastest-growing age group in the US. Spinal deformity is a major problem affecting the elderly and, therefore, the demand for surgery for spinal deformity is becoming increasingly prevalent in elderly patients. Much of the literature on surgery for adult deformity focuses on patients who are younger than 60 years, and therefore there is limited information about the complications and outcomes of surgery in the elderly population. In this study, the authors undertook a review of the literature on spinal deformity surgery in patients older than 60 years. The authors discuss their analysis with a focus on outcomes, complications, discrepancies between individual studies, and strategies for complication avoidance.
Related JoVE Video
A submicron plasmonic dichroic splitter.
Nat Commun
PUBLISHED: 08-02-2011
Show Abstract
Hide Abstract
Spectral imaging and sensing techniques, new solar cell designs and wavelength-division multiplexing in optical communication rely on structures that collect and sort photons by wavelength. The strong push for chip-scale integration of such optical components has necessitated ultracompact, planar structures, and fomented great interest in identifying the smallest possible devices. Consequently, novel micro-ring, photonic crystal and plasmonic solutions have emerged. Meanwhile, the optical coupling of subwavelength plasmonic structures supporting a very limited number of modes has also enabled new functionalities, including Fano resonances and structural electromagnetically-induced transparency. Here we show how two similarly sized subwavelength metal grooves can form an ultracompact submicron plasmonic dichroic splitter. Each groove supports just two electromagnetic modes of opposite symmetry that allows independent control of how a groove collects free-space photons and directs surface plasmon polaritons. These results show how the symmetry of electromagnetic modes can be exploited to build compact optical components.
Related JoVE Video
Perioperative results following open and minimally invasive single-level lumbar discectomy.
J Clin Neurosci
PUBLISHED: 04-11-2011
Show Abstract
Hide Abstract
Lumbar discectomy is the most commonly performed spine surgery and in recent years, minimally invasive tubular discectomy has become increasingly popular among surgeons and patients. However, recent reports have raised the question of whether or not patients have shorter hospitalizations following minimally invasive discectomy. From 2005 to 2010, we analyzed 109 patients who underwent elective, single-level lumbar discectomy for central or paracentral disc herniations. A retrospective analysis of medical records was performed for perioperative complications. Tubular discectomy was not associated with increased rates of durotomy, nerve root injury, wound complications, or recurrent disc herniations requiring additional surgery. Minimally invasive tubular discectomy in the lumbar spine results in a small, but statistically significant, advantage in length of stay compared to conventional open microdiscectomy. While small on an individual basis, this difference may translate to substantial economic savings over time when one considers how many discectomies are performed in aggregate.
Related JoVE Video
Changes in coronal and sagittal plane alignment following minimally invasive direct lateral interbody fusion for the treatment of degenerative lumbar disease in adults: a radiographic study.
J Neurosurg Spine
PUBLISHED: 04-08-2011
Show Abstract
Hide Abstract
The lateral transpsoas approach for lumbar interbody fusion is a minimal access technique that has been used by some to treat lumbar degenerative conditions, including degenerative scoliosis. Few studies, however, have analyzed its effect on coronal and sagittal plane correction, and no study has compared changes in segmental, regional, and global coronal and sagittal alignment after this technique. The object of this study was to determine changes in sagittal and coronal plane alignment occurring after direct lateral interbody fusion (DLIF).
Related JoVE Video
Surgical management of cervical ossification of the posterior longitudinal ligament: natural history and the role of surgical decompression and stabilization.
Neurosurg Focus
PUBLISHED: 03-26-2011
Show Abstract
Hide Abstract
Ossification of the posterior longitudinal ligament (OPLL) is a complex multifactorial disease process combining both metabolic and biomechanical factors. The role for surgical intervention and choice of anterior or posterior approach is controversial. The object of this study was to review the literature and present a single-institution experience with surgical intervention for OPLL.
Related JoVE Video
Pluripotency factors in embryonic stem cells regulate differentiation into germ layers.
Cell
PUBLISHED: 03-03-2011
Show Abstract
Hide Abstract
Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells.
Related JoVE Video
Management of ossification of the posterior longitudinal ligament of the thoracic spine.
Neurosurg Focus
PUBLISHED: 03-03-2011
Show Abstract
Hide Abstract
The management of thoracic ossification of the posterior longitudinal ligament has been studied by many spinal surgeons. Indications for operative intervention include progressive radiculopathy, myelopathy, and neurological deterioration. The ideal surgery for decompression remains highly debatable as various methods of surgical treatment of ossification of the posterior longitudinal ligament have been devised. Although numerous modifications to the 3 main approaches have been identified (anterior, posterior, or lateral), the indication for each depends on the nature of compression, the morphology of the lesion, the level of the compression, the structural alignment of the spine, and the neurological status of the patient. The authors discuss treatment techniques for thoracic ossification of the posterior longitudinal ligament, cite case examples from a single institution, and review the literature.
Related JoVE Video
Approach-related complications after decompression for cervical ossification of the posterior longitudinal ligament.
Neurosurg Focus
PUBLISHED: 03-03-2011
Show Abstract
Hide Abstract
The surgical management of compressive cervical ossification of the posterior longitudinal ligament (OPLL) can be challenging. Traditionally, approach indications for decompression of cervical spondylotic myelopathy have been used. However, the postoperative complication profile after cervical OPLL decompression is unique and may require an alternative approach paradigm. The authors review the literature on approach-related OPLL complications and suggest a management strategy for patients with single- or multiple-segment OPLL with or without greater than 50% canal stenosis.
Related JoVE Video
Asymmetry of 24-hour intraocular pressure reduction by topical ocular hypotensive medications in fellow eyes.
Ophthalmology
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
A core assumption for the 1-eye therapeutic trial of ocular hypotensive medications is the symmetrical reduction of intraocular pressure (IOP) in paired eyes. This assumption was evaluated for 24-hour IOP reduction in patients who underwent monotherapy or adjunctive therapy.
Related JoVE Video
Management of recurrent adult tethered cord syndrome.
Neurosurg Focus
PUBLISHED: 07-03-2010
Show Abstract
Hide Abstract
Recurrent tethered cord syndrome (TCS) can lead to significant progressive disability in adults. The diagnosis of TCS is made with a high degree of clinical suspicion. In the adult population, many patients receive inadequate care unless they are seen at a multidisciplinary clinic. Successful detethering procedures require careful intradural dissection and meticulous wound and dural closure. With multiple revision procedures, vertebral column shortening has become an appropriate alternative to surgical detethering.
Related JoVE Video
Circadian variations in intracranial pressure and translaminar pressure difference in Sprague-Dawley rats.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 06-23-2010
Show Abstract
Hide Abstract
To study the circadian (24-hour) change in intracranial pressure (ICP) in conscious, freely moving rats and to project the circadian change in translaminar pressure difference.
Related JoVE Video
The Ribavirin Pregnancy Registry: Findings after 5 years of enrollment, 2003-2009.
Birth Defects Res. Part A Clin. Mol. Teratol.
PUBLISHED: 06-22-2010
Show Abstract
Hide Abstract
Ribavirin, with interferons or pegylated interferons, is used to treat chronic hepatitis C. Ribavirin is contraindicated in pregnancy (FDA Pregnancy Category X) and in men whose partners may become pregnant. In 2003, the Ribavirin Pregnancy Registry was established to monitor pregnancy exposures to ribavirin and to evaluate the potential human teratogenicity of prenatal exposure.
Related JoVE Video
Heterogeneity and dynamics of the ligand recognition mode in purine-sensing riboswitches.
Biochemistry
PUBLISHED: 03-30-2010
Show Abstract
Hide Abstract
High-resolution crystal structures and biophysical analyses of purine-sensing riboswitches have revealed that a network of hydrogen bonding interactions appear to be largey responsible for discrimination of cognate ligands against structurally related compounds. Here we report that by using femtosecond time-resolved fluorescence spectroscopy to capture the ultrafast decay dynamics of the 2-aminopurine base as the ligand, we have detected the presence of multiple conformations of the ligand within the binding pockets of one guanine-sensing and two adenine-sensing riboswitches. All three riboswitches have similar conformational distributions of the ligand-bound state. The known crystal structures represent the global minimum that accounts for 50-60% of the population, where there is no significant stacking interaction between the ligand and bases of the binding pocket, but the hydrogen-bonding cage collectively provides an electronic environment that promotes an ultrafast ( approximately 1 ps) charge transfer pathway. The ligand also samples multiple conformations in which it significantly stacks with either the adenine or the uracil bases of the A21-U75 and A52-U22 base pairs that form the ceiling and floor of the binding pocket, respectively, but favors the larger adenine bases. These alternative conformations with well-defined base stacking interactions are approximately 1-1.5 kcal/mol higher in DeltaG degrees than the global minimum and have distinct charge transfer dynamics within the picosecond to nanosecond time regime. Inside the pocket, the purine ligand undergoes dynamic motion on the low nanosecond time scale, sampling the multiple conformations based on time-resolved anisotropy decay dynamics. These results allowed a description of the energy landscape of the bound ligand with intricate details and demonstrated the elastic nature of the ligand recognition mode by the purine-sensing riboswitches, where there is a dynamic balance between hydrogen bonding and base stacking interactions, yielding the high affinity and specificity by the aptamer domain.
Related JoVE Video
Logic integration of mRNA signals by an RNAi-based molecular computer.
Nucleic Acids Res.
PUBLISHED: 03-01-2010
Show Abstract
Hide Abstract
Synthetic in vivo molecular computers could rewire biological processes by establishing programmable, non-native pathways between molecular signals and biological responses. Multiple molecular computer prototypes have been shown to work in simple buffered solutions. Many of those prototypes were made of DNA strands and performed computations using cycles of annealing-digestion or strand displacement. We have previously introduced RNA interference (RNAi)-based computing as a way of implementing complex molecular logic in vivo. Because it also relies on nucleic acids for its operation, RNAi computing could benefit from the tools developed for DNA systems. However, these tools must be harnessed to produce bioactive components and be adapted for harsh operating environments that reflect in vivo conditions. In a step toward this goal, we report the construction and implementation of biosensors that transduce mRNA levels into bioactive, small interfering RNA molecules via RNA strand exchange in a cell-free Drosophila embryo lysate, a step beyond simple buffered environments. We further integrate the sensors with our RNAi computational module to evaluate two-input logic functions on mRNA concentrations. Our results show how RNA strand exchange can expand the utility of RNAi computing and point toward the possibility of using strand exchange in a native biological setting.
Related JoVE Video
Diurnal and nocturnal effects of brimonidine monotherapy on intraocular pressure.
Ophthalmology
PUBLISHED: 02-26-2010
Show Abstract
Hide Abstract
To investigate the effect of brimonidine monotherapy on intraocular pressure (IOP) during the nocturnal/sleep period.
Related JoVE Video
Minimally invasive circumferential spinal decompression and stabilization for symptomatic metastatic spine tumor: technical case report.
Neurosurgery
PUBLISHED: 02-23-2010
Show Abstract
Hide Abstract
Metastatic epidural spinal cord compression is a potentially devastating complication of cancer and is estimated to occur in 5% to 14% of all cancer patients. It is best treated surgically. Minimally invasive spine surgery has the potential benefits of decreased surgical approach-related morbidity, blood loss, hospital stay, and time to mobilization.
Related JoVE Video
Osteophyte formation after multilevel anterior cervical discectomy and fusion causing a delayed presentation of functional dysphagia.
Spine J
PUBLISHED: 02-13-2010
Show Abstract
Hide Abstract
Anterior cervical discectomy and fusion (ACDF) is a common procedure used to treat radiculopathy and myelopathy from cervical degenerative disc disease. The complications for this procedure are well known. Dysphagia can occur in the postoperative setting. However, it is typically transient and does not last longer than 1 month after an operation. A de novo presentation of dysphagia occurring years after an operation is unique. Osteophyte formation can cause mass effect on the esophagus leading to obstruction of this conduit. However, there have been no reported cases of osteophyte growth fusing to surrounding structures leading to a functional dysphagia.
Related JoVE Video
Side-coupled cavity model for surface plasmon-polariton transmission across a groove.
Opt Express
PUBLISHED: 11-13-2009
Show Abstract
Hide Abstract
We demonstrate that the transmission properties of surface plasmon-polaritons (SPPs) across a rectangular groove in a metallic film can be described by an analytical model that treats the groove as a side-coupled cavity to propagating SPPs on the metal surface. The coupling efficiency to the groove is quantified by treating it as a truncated metal-dielectric-metal (MDM) waveguide. Finite-difference frequency-domain (FDFD) simulations and mode orthogonality relations are employed to derive the basic scattering coefficients that describe the interaction between the relevant modes in the system. The modeled SPP transmission and reflection intensities show excellent agreement with full-field simulations over a wide range of groove dimensions, validating this intuitive model. The model predicts the sharp transmission minima that occur whenever an incident SPP resonantly couples to the groove. We also for the first time show the importance of evanescent, reactive MDM SPP modes to the transmission behavior. SPPs that couple to this mode are resonantly enhanced upon reflection from the bottom of the groove, leading to high field intensities and sharp transmission minima across the groove. The resonant behavior exhibited by the grooves has a number of important device applications, including SPP mirrors, filters, and modulators.
Related JoVE Video
Retinal basement membrane abnormalities and the retinopathy of Alport syndrome.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-22-2009
Show Abstract
Hide Abstract
To determine the effects of X-linked and autosomal recessive Alport syndrome on retinal basement membranes and how these result in the characteristic perimacular dot-and-fleck retinopathy, lozenge, and macular hole.
Related JoVE Video
The median effective dose of bupivacaine, levobupivacaine, and ropivacaine after intrathecal injection in lower limb surgery.
Anesth. Analg.
PUBLISHED: 09-19-2009
Show Abstract
Hide Abstract
Intrathecal anesthesia is commonly used for lower limb surgery. Bupivacaine, levobupivacaine, and ropivacaine have all been used as intrathecal drugs, but their relative potency in this context has not been fully determined. In this study, we determined the median effective dose (ED(50)) of these three local anesthetics for intrathecal anesthesia in lower limb surgery and hence their relative potencies.
Related JoVE Video
Basilar artery occlusion following C1 lateral mass fracture managed by mechanical and pharmacological thrombolysis.
Neurocrit Care
PUBLISHED: 09-18-2009
Show Abstract
Hide Abstract
Vertebral artery injury following cervical spine trauma can be associated with stroke. We present a case of a C1 fracture resulting in vertebral artery dissection and neurological decline as a result of basilar artery occlusion treated with chemical and mechanical thrombolysis resulting in basilar artery patency and clinical improvement.
Related JoVE Video
Increased 24-hour variation of human intraocular pressure with short axial length.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 09-09-2009
Show Abstract
Hide Abstract
To characterize 24-hour variation of intraocular pressure (IOP) in healthy young adults based on the axial length of the eye.
Related JoVE Video
Elastomeric microfluidic diode and rectifier work with Newtonian fluids.
J Appl Phys
PUBLISHED: 06-09-2009
Show Abstract
Hide Abstract
We report on two microfluidic elastomeric autoregulatory devices-a diode and a rectifier. They exhibit physically interesting and complex nonlinear behaviors (saturation, bias-dependent resistance, and rectification) with a Newtonian fluid. Due to their autoregulatory properties, they operate without active external control. As a result, they enable increased microfluidic device density and overall system miniaturization. The demonstrated diode and rectifier would also be useful components in future microfluidic logic circuitry.
Related JoVE Video
Pathophysiology of glaucoma and continuous measurements of intraocular pressure.
Mol Cell Biomech
PUBLISHED: 04-23-2009
Show Abstract
Hide Abstract
Glaucoma is a leading cause of visual impairment and blindness worldwide. The main risk factor for glaucoma is an elevated intraocular pressure (IOP), which is also the only currently treatable risk factor. Despite its importance, our understanding of IOP is incomplete and our ability to measure IOP is limited. IOP is known to undergo both random fluctuations as well as variations following a circadian pattern. In humans, IOP is highest at night and lower during the daytime, largely due to changes in body position, although other factors appear to contribute. In rabbits, IOP is also highest at night and lower during the day, likely due to circadian variations in sympathetic nervous system activity. Random and circadian IOP variations may be important to glaucoma pathogenesis, independent of the diurnal IOP level. However, due to limitations with current IOP measurement technology, clinical practice typically involves only a few IOP measurements per year. As well, current technology does not allow 24-hour monitoring of pressure without the use of sleep laboratories or hospital admission. Two strategies for automating IOP measurement are temporary (non-invasive) monitoring and permanent (implantable) monitoring. Efforts at developing devices to allow continuous IOP monitoring have occurred for over 40 years without producing a clinical device. Current technological progress would seem to suggest that such devices are possible at this time, and a review of previous attempts provides guidelines for their development.
Related JoVE Video
Affinity of drugs and small biologically active molecules to carbon nanotubes: a pharmacodynamics and nanotoxicity factor?
Mol. Pharm.
PUBLISHED: 03-14-2009
Show Abstract
Hide Abstract
The MM-PBSA MD method was used to estimate the affinity, as represented by log k(b), of each of a variety of biologically active molecules to a carbon nanotube in an aqueous environment. These ligand-receptor binding simulations were calibrated by first estimating the log k(b) values for eight ligands to human serum albumin, HSA, whose log k(b) values have been observed. A validation linear correlation equation was established [R(2) = 0.888, Q(2) = 0.603] between the observed and estimated log k(b) values to HSA. This correlation equation was then used to rescale all MM-PBSA MD log k(b) values using a carbon nanotube as the receptor. The log k(b) of the eight HSA ligands, nine polar and/or rigid ligands and six nonpolar and/or flexible ligands to a carbon nanotube were estimated. The range in rescaled log k(b) values across this set of 23 ligands is 0.25 to 7.14, essentially 7 orders of magnitude. Some ligands, like PGI2, bind in the log k(b) = 7 range which corresponds to the lower limits of known drugs. Thus, such significant levels of binding of biologically relevant compounds to carbon nanotubes might lead to alterations in the normal pharmacodynamic profiles of these compounds and be a source of toxicity. Ligand binding potency to a carbon nanotube is largely controlled by the shape, polarity/nonpolarity distribution and flexibility of the ligand. HSA ligands exhibit the most limited binding to a carbon nanotube, and they are relatively rigid and of generally spherical shape. Polar and/or rigid ligands bind less strongly to the carbon nanotube, on average, than nonpolar and/or flexible ligands even though the chosen members of both classes of ligands in this study have chainlike shapes that facilitate binding. The introduction of only a few strategically spaced single bonds in the polar and/or rigid ligands markedly increases their binding to a carbon nanotube.
Related JoVE Video
Surgical management of superficial siderosis.
Spine J
PUBLISHED: 03-03-2009
Show Abstract
Hide Abstract
Superficial siderosis is a rare condition resulting from the presence of chronic bleeding into the subarachnoid space usually causing gait instability and deafness. The surgical management of superficial siderosis depends on localizing the source of hemorrhage.
Related JoVE Video
Intraocular pressure measurements throughout the 24 h.
Curr Opin Ophthalmol
PUBLISHED: 02-26-2009
Show Abstract
Hide Abstract
This review summarizes the relationship of 24 h intraocular pressure (IOP) on the management of glaucoma.
Related JoVE Video
Relationship of the 24-hour pattern of intraocular pressure with optic disc appearance in primary open-angle glaucoma.
Ophthalmology
PUBLISHED: 02-04-2009
Show Abstract
Hide Abstract
To study the relationship between the 24-hour pattern of intraocular pressure (IOP) with optic disc appearance in primary open-angle glaucoma (POAG) patients.
Related JoVE Video
Effect of cloretazine (VNP40101M) on acute myeloid leukaemia blast cells in vitro as a single agent and combined with cytarabine and daunorubicin.
Leuk. Res.
PUBLISHED: 01-23-2009
Show Abstract
Hide Abstract
We have investigated the effect of cloretazine (VNP40101M or Laromustine), a novel sulfonylhydrazine alkylating agent with significant antileukaemic activity, alone, or combined with cytarabine or daunorubicin, on the proliferation, viability and apoptosis of cell lines and acute myeloid leukaemia blast cells in vitro. Cloretazine alone induced a concentration-dependent inhibition of proliferation, reduction in cell viability and an increase in apoptosis in all samples tested. Combinations of cloretazine with varying concentrations of cytarabine or daunorubicin further enhanced these inhibitory effects, suggesting VNP40101M may have a role in combined low dose chemotherapy regimes especially in the elderly.
Related JoVE Video
Comparing diurnal and nocturnal effects of brinzolamide and timolol on intraocular pressure in patients receiving latanoprost monotherapy.
Ophthalmology
PUBLISHED: 01-20-2009
Show Abstract
Hide Abstract
To compare the diurnal and nocturnal effects of brinzolamide and timolol on intraocular pressure (IOP) in patients already receiving monotherapy with latanoprost.
Related JoVE Video
Vav proteins are necessary for correct differentiation of mouse cecal and colonic enterocytes.
J. Cell. Sci.
PUBLISHED: 01-12-2009
Show Abstract
Hide Abstract
In the mammalian cecum and colon, a single layer of absorptive, mature enterocytes are a crucial element of the physical barrier to the contents of the lumen. Enterocytic differentiation involves expansion of cytoplasmic cytoskeletal networks, which have been proposed to maintain structural integrity of individual cells and thus the entire epithelial barrier. We sought molecular tools to test this hypothesis in vivo, because in vitro systems displaying full intestinal epithelial differentiation have not yet been developed. Vav proteins are RhoGEFs that modulate cytoskeletal networks in immune cells. We found that Vav proteins were preferentially expressed in terminally differentiating cecal and colonic enterocytes. Loss of Vav protein expression in triple-knockout mice (Vav1(-/-);Vav2(-/-);Vav3(-/-)) resulted in defective expansion of microtubule cytoskeletons, a significant decrease in cell height and diminished expression of differentiation markers. Despite these changes, enterocytes in the triple-mutant mice did not contain measurable alterations in actin cytoskeleton, apical cell-cell junctions, nuclear position or global polarized delivery of proteins involved in terminal differentiation. Aged triple-mutant mice spontaneously developed ulcerative lesions that were, in part, a result of defective wound repair. These studies show that Vav proteins are required for enterocytic differentiation and colonic epithelial barrier integrity.
Related JoVE Video
Intradermal needle-free powdered drug injection by a helium-powered device.
Conf Proc IEEE Eng Med Biol Soc
Show Abstract
Hide Abstract
We present a new method for needle-free powdered drug injection via a bench-top gas-powered device. This injector provides an alternative method of vaccine delivery to address the cold chain problem--the cost and risk of transporting temperature sensitive vaccines to developing countries. The device houses interchangeable nozzle inserts to vary orifice geometries and is capable of delivering polymer beads (1-5 µm diameter) into the dermal layer of porcine tissue. Results for injection shape and injection depth versus nozzle orifice diameter demonstrate the devices controllability.
Related JoVE Video
Analysis of continuous 24-hour intraocular pressure patterns in glaucoma.
Invest. Ophthalmol. Vis. Sci.
Show Abstract
Hide Abstract
To present a method to analyze circadian intraocular pressure (IOP) patterns in glaucoma patients and suspects undergoing repeated continuous 24-hour IOP monitoring.
Related JoVE Video
The potential for cellular therapy combined with growth factors in spinal cord injury.
Stem Cells Int
Show Abstract
Hide Abstract
Any traumatic spinal cord injury (SCI) may cause symptoms ranging from pain to complete loss of motor and sensory functions below the level of the injury. Currently, there are over 2 million SCI patients worldwide. The cost of their necessary continuing care creates a burden for the patient, their families, and society. Presently, few SCI treatments are available and none have facilitated neural regeneration and/or significant functional improvement. Research is being conducted in the following areas: pathophysiology, cellular therapies (Schwann cells, embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, olfactory ensheathing cells), growth factors (BDNF), inhibitory molecules (NG2, myelin protein), and combination therapies (cell grafts and neurotrophins, cotransplantation). Results are often limited because of the inhibitory environment created following the injury and the limited regenerative potential of the central nervous system. Therapies that show promise in small animal models may not transfer to nonhuman primates and humans. None of the research has resulted in remarkable improvement, but many areas show promise. Studies have suggested that a combination of therapies may enhance results and may be more effective than a single therapy. This paper reviews and discusses the most promising new SCI research including combination therapies.
Related JoVE Video
Twenty-four-hour effects of bimatoprost 0.01% monotherapy on intraocular pressure and ocular perfusion pressure.
BMJ Open
Show Abstract
Hide Abstract
To investigate the 24 h effects of bimatoprost 0.01% monotherapy on intraocular pressure (IOP) and ocular perfusion pressure (OPP).
Related JoVE Video
Minimal residual disease monitoring by quantitative RT-PCR in core binding factor AML allows risk stratification and predicts relapse: results of the United Kingdom MRC AML-15 trial.
Blood
Show Abstract
Hide Abstract
The clinical value of serial minimal residual disease (MRD) monitoring in core binding factor (CBF) acute myeloid leukemia (AML) by quantitative RT-PCR was prospectively assessed in 278 patients [163 with t(8;21) and 115 with inv(16)] entered in the United Kingdom MRC AML 15 trial. CBF transcripts were normalized to 10(5) ABL copies. At remission, after course 1 induction chemotherapy, a > 3 log reduction in RUNX1-RUNX1T1 transcripts in BM in t(8;21) patients and a > 10 CBFB-MYH11 copy number in peripheral blood (PB) in inv(16) patients were the most useful prognostic variables for relapse risk on multivariate analysis. MRD levels after consolidation (course 3) were also informative. During follow-up, cut-off MRD thresholds in BM and PB associated with a 100% relapse rate were identified: for t(8;21) patients BM > 500 copies, PB > 100 copies; for inv(16) patients, BM > 50 copies and PB > 10 copies. Rising MRD levels on serial monitoring accurately predicted hematologic relapse. During follow-up, PB sampling was equally informative as BM for MRD detection. We conclude that MRD monitoring by quantitative RT-PCR at specific time points in CBF AML allows identification of patients at high risk of relapse and could now be incorporated in clinical trials to evaluate the role of risk directed/preemptive therapy.
Related JoVE Video
Quantitative multiplex quantum dot in-situ hybridisation based gene expression profiling in tissue microarrays identifies prognostic genes in acute myeloid leukaemia.
Biochem. Biophys. Res. Commun.
Show Abstract
Hide Abstract
Measurement and validation of microarray gene signatures in routine clinical samples is problematic and a rate limiting step in translational research. In order to facilitate measurement of microarray identified gene signatures in routine clinical tissue a novel method combining quantum dot based oligonucleotide in situ hybridisation (QD-ISH) and post-hybridisation spectral image analysis was used for multiplex in-situ transcript detection in archival bone marrow trephine samples from patients with acute myeloid leukaemia (AML). Tissue-microarrays were prepared into which white cell pellets were spiked as a standard. Tissue microarrays were made using routinely processed bone marrow trephines from 242 patients with AML. QD-ISH was performed for six candidate prognostic genes using triplex QD-ISH for DNMT1, DNMT3A, DNMT3B, and for HOXA4, HOXA9, Meis1. Scrambled oligonucleotides were used to correct for background staining followed by normalisation of expression against the expression values for the white cell pellet standard. Survival analysis demonstrated that low expression of HOXA4 was associated with poorer overall survival (p=0.009), whilst high expression of HOXA9 (p<0.0001), Meis1 (p=0.005) and DNMT3A (p=0.04) were associated with early treatment failure. These results demonstrate application of a standardised, quantitative multiplex QD-ISH method for identification of prognostic markers in formalin-fixed paraffin-embedded clinical samples, facilitating measurement of gene expression signatures in routine clinical samples.
Related JoVE Video
Positional independence of optic nerve head and retinal nerve fiber layer thickness measurements with spectral-domain optical coherence tomography.
Am. J. Ophthalmol.
Show Abstract
Hide Abstract
To evaluate repeatability and positional independence of optic nerve head (ONH) and retinal nerve fiber layer (RNFL) thickness measurements in sitting and supine body positions using portable spectral-domain optical coherence tomography (iVue SD-OCT; Optovue Inc).
Related JoVE Video
Direct lateral interbody fusion (DLIF) at the lumbosacral junction L5-S1.
J Clin Neurosci
Show Abstract
Hide Abstract
The direct lateral interbody fusion (DLIF), a minimally invasive lateral approach for placement of an interbody fusion device, does not require nerve root retraction or any contact with the great vessels and can lead to short operative times with little blood loss. Due to anatomical restrictions, this procedure has not been used at the lumbosacral (L5-S1) junction. Lumbosacral transitional vertebrae (LSTV), a structural anomaly of the lumbosacral spine associated with low back pain, can result in a level being wrongly identified pre-operatively due to misnumbering of the vertebral levels. To our knowledge, use of the DLIF graft in this patient is the first report of an interbody fusion graft being placed at the disc space between the LSTV and S1 via the transpsoas route. We present a review of the literature regarding the LSTV variation as well as the lateral placement of interbody fusion grafts at the lumbosacral junction.
Related JoVE Video
Efficacy of surgical preparation solutions in lumbar spine surgery.
J Bone Joint Surg Am
Show Abstract
Hide Abstract
Postoperative spinal wound infections are relatively common and are often associated with increased morbidity and poor long-term patient outcomes. The purposes of this study were to identify the common bacterial flora on the skin overlying the lumbar spine and evaluate the efficacy of readily available skin-preparation solutions in the elimination of bacterial pathogens from the surgical site following skin preparation.
Related JoVE Video
Metastatic gastrointestinal stromal tumor to the thoracic and lumbar spine: first reported case and surgical treatment.
Spine J
Show Abstract
Hide Abstract
Metastatic epidural spinal cord compression from gastrointestinal stromal tumors (GISTs) is a rarely reported phenomenon.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.