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.
Identification of a Neurologic Scale That Optimizes EMS Detection of Older Adult Traumatic Brain Injury Patients Who Require Transport to a Trauma Center.
Prehosp Emerg Care
PUBLISHED: 10-08-2014
Show Abstract
Hide Abstract
Abstract Objective. We sought to identify a scale or components of a scale that optimize detection of older adult traumatic brain injury (TBI) patients who require transport to a trauma center, regardless of mechanism. Methods. We assembled a consensus panel consisting of nine experts in geriatric emergency medicine, prehospital medicine, trauma surgery, geriatric medicine, and TBI, as well as prehospital providers, to evaluate the existing scales used to identify TBI. We reviewed the relevant literature and solicited group feedback to create a list of candidate scales and criteria for evaluation. Using the nominal group technique, scales were evaluated by the expert panel through an iterative process until consensus was achieved. Results. We identified 15 scales for evaluation. The panel's criteria for rating the scales included ease of administration, prehospital familiarity with scale components, feasibility of use with older adults, time to administer, and strength of evidence for their performance in the prehospital setting. After review and discussion of aggregated ratings, the panel identified the Simplified Motor Scale, GCS-Motor Component, and AVPU (alert, voice, pain, unresponsive) as the strongest scales, but determined that none meet all EMS provider and patient needs due to poor usability and lack of supportive evidence. The panel proposed that a dichotomized decision scheme that includes domains of the top-rated scales -level of alertness (alert vs. not alert) and motor function (obeys commands vs. does not obey) -may be more effective in identifying older adult TBI patients who require transport to a trauma center in the prehospital setting. Conclusions. Existing scales to identify TBI are inadequate to detect older adult TBI patients who require transport to a trauma center. A new algorithm, derived from elements of previously established scales, has the potential to guide prehospital providers in improving the triage of older adult TBI patients, but needs further evaluation prior to use.
Related JoVE Video
Single nucleotide polymorphisms in AREG and EREG are prognostic biomarkers in locally advanced gastric cancer patients after surgery with curative intent.
Pharmacogenet. Genomics
PUBLISHED: 09-10-2014
Show Abstract
Hide Abstract
Amphiregulin (AREG) and epiregulin (EREG) are important ligands to the epithelial growth factor receptor, which is involved in the regulation of progression and stemness in gastric cancer (GC). This study investigated whether frequent single nucleotide polymorphisms (SNPs) in genes of AREG and EREG are associated with recurrence-free survival and overall survival in patients with locally advanced GC.
Related JoVE Video
Radial to axillary nerve neurotization for brachial plexus injury in children: a combined case series.
J Neurosurg Pediatr
PUBLISHED: 09-05-2014
Show Abstract
Hide Abstract
Object Axillary nerve palsy, isolated or as part of a more complex brachial plexus injury, can have profound effects on upper-extremity function. Radial to axillary nerve neurotization is a useful technique for regaining shoulder abduction with little compromise of other neurological function. A combined experience of this procedure used in children is reviewed. Methods A retrospective review of the authors' experience across 3 tertiary care centers with brachial plexus and peripheral nerve injury in children (younger than 18 years) revealed 7 cases involving patients with axillary nerve injury as part of an overall brachial plexus injury with persistent shoulder abduction deficits. Two surgical approaches to the region were used. Results Four infants (ages 0.6, 0.8, 0.8, and 0.6 years) and 3 older children (ages 8, 15, and 17 years) underwent surgical intervention. No patient had significant shoulder abduction past 15° preoperatively. In 3 cases, additional neurotization was performed in conjunction with the procedure of interest. Two surgical approaches were used: posterior and transaxillary. All patients displayed improvement in shoulder abduction. All were able to activate their deltoid muscle to raise their arm against gravity and 4 of 7 were able to abduct against resistance. The median duration of follow-up was 15 months (range 8 months to 5.9 years). Conclusions Radial to axillary nerve neurotization improved shoulder abduction in this series of patients treated at 3 institutions. While rarely used in children, this neurotization procedure is an excellent option to restore deltoid function in children with brachial plexus injury due to birth or accidental trauma.
Related JoVE Video
Gastrointestinal cancer: targeted therapies in gastric cancer-the dawn of a new era.
Nat Rev Clin Oncol
PUBLISHED: 08-29-2014
Show Abstract
Hide Abstract
The international phase III REGARD study demonstrated improved overall survival with ramucirumab as second-line therapy for patients with advanced-stage gastric and gastroesophageal junction adenocarcinoma. As a novel biological treatment, is ramucirumab also the harbinger of a new era of targeted therapies in this prevalent and highly morbid disease?
Related JoVE Video
The role of ¹?F-FDG PET imaging in upper gastrointestinal malignancies.
Curr Treat Options Oncol
PUBLISHED: 07-28-2014
Show Abstract
Hide Abstract
Cancers of the upper gastrointestinal tract form a prevalent and highly morbid group of malignancies. Specifically, median survival for patients with esophagus, gastric, and pancreatic cancers is less than 1 year, and although there has been progress in therapeutic strategies, the vast majority of newly diagnosed patients with these cancers will die of their disease. (18)F-FDG PET ((18)f-fluorodeoxyglucose positron emission tomography) is a useful but underutilized resource for identifying metastatic disease in the upper gastrointestinal tract. While prevalent in the United States, worldwide, (18)F-FDG PET is underutilized especially in countries with a growing emergence of gastroesophageal cancers, despite evidence of clear benefit in cancer staging, and in some cases response assessment and surveillance.
Related JoVE Video
The development of bevacizumab in noncolorectal gastrointestinal malignancies: gastroesophageal, pancreatic, and hepatocellular carcinoma.
Clin Adv Hematol Oncol
PUBLISHED: 07-09-2014
Show Abstract
Hide Abstract
Bevacizumab (Avastin, Genentech) is a potent inhibitor of vascular endothelial growth factor A that has demonstrated modest antitumor activity across a broad range of malignancies when combined with chemotherapy. In colorectal cancer, bevacizumab in combination with chemotherapy is a standard of care for first-line therapy, and is used as second-line therapy in both bevacizumab-naive patients and those who have progressed on first-line therapy containing bevacizumab. Bevacizumab has been examined in nongastrointestinal malignancies as well. Across these multiple studies, virtually all of which demonstrate some improvement in progression-free survival, the combination of chemotherapy and bevacizumab has not led to a significant improvement in overall survival. Unfortunately, the addition of bevacizumab to chemotherapy translates into only slight improvement in overall survival in a few malignancies, including colorectal cancer. In this review, we highlight the development of bevacizumab in noncolorectal gastrointestinal malignancies, and potential future directions in antiangiogenic drug development.
Related JoVE Video
A consensus-based criterion standard for trauma center need.
J Trauma Acute Care Surg
PUBLISHED: 03-26-2014
Show Abstract
Hide Abstract
In civilian trauma care, field triage is the process applied by prehospital care providers to identify patients who are likely to have severe injuries and immediately need the resources of a trauma center. Studies of the efficacy of field triage have used various measures to define trauma center need because no "criterion standard" exists, making cross-study comparisons difficult. This study aimed to develop a consensus-based functional criterion standard definition of trauma center need.
Related JoVE Video
Is gastric cancer different in Korea and the United States? Impact of tumor location on prognosis.
Ann. Surg. Oncol.
PUBLISHED: 03-06-2014
Show Abstract
Hide Abstract
To compare the characteristics and prognoses of gastric cancers by tumor location in Korean and U.S. subjects after curative-intent (R0) resection for gastric cancer (GC).
Related JoVE Video
Geriatric-Specific Triage Criteria Are More Sensitive Than Standard Adult Criteria in Identifying Need for Trauma Center Care in Injured Older Adults.
Ann Emerg Med
PUBLISHED: 02-25-2014
Show Abstract
Hide Abstract
We evaluate the sensitivity of Ohio's 2009 emergency medical services (EMS) geriatric trauma triage criteria compared with the previous adult triage criteria in identifying need for trauma center care among older adults.
Related JoVE Video
EMSC program manager survey on education of prehospital providers.
Prehosp Emerg Care
PUBLISHED: 02-18-2014
Show Abstract
Hide Abstract
Although pediatric-specific objectives for the initial education of prehospital providers have been established, uniform implementation of these objectives and guidelines for hours of required pediatric continuing education (CE) for prehospital providers have not been established.
Related JoVE Video
Phase II trial of bortezomib alone or in combination with irinotecan in patients with adenocarcinoma of the gastroesophageal junction or stomach.
Invest New Drugs
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
To determine the effectiveness of bortezomib plus irinotecan and bortezomib alone in patients with advanced gastroesophageal junction (GEJ) and gastric adenocarcinoma. We also sought to explore the effect of these therapeutics on tumor and normal gene expression in vivo.
Related JoVE Video
Anatomical aberrations in root canals of maxillary first and second molar teeth: an endodontic challenge.
BMJ Case Rep
PUBLISHED: 01-22-2014
Show Abstract
Hide Abstract
Root canal anatomy variations present a constant challenge in successful diagnosis and endodontic treatment, especially the multirooted teeth. Maxillary first molar is the most commonly treated tooth yet with frequent failures because of undetected canals, especially the mesiobuccal second canal (MB2) with more frequency and distobuccal second canal (DB2) with quite a less frequency. Also, there are limited chances to find MB2 in maxillary second molars. We present two such cases, each of maxillary first and second molar with extra distobuccal and mesiobuccal canals, respectively.
Related JoVE Video
Stage-stratified prognosis of signet ring cell histology in patients undergoing curative resection for gastric adenocarcinoma.
Ann. Surg. Oncol.
PUBLISHED: 01-07-2014
Show Abstract
Hide Abstract
The prognosis of signet ring cell (SRC) gastric adenocarcinoma is regarded as poor, although studies addressing outcomes in relation to non-SRC tumors are conflicting. Our objective was to compare the survival of SRC tumors with stage-matched intestinal-type tumors in a cohort of Western patients.
Related JoVE Video
Transforming emergency care for older adults.
Health Aff (Millwood)
PUBLISHED: 12-05-2013
Show Abstract
Hide Abstract
Already crowded and stressful, US emergency departments (EDs) are facing the challenge of serving an aging population that requires complex and lengthy evaluations. Creative solutions are necessary to improve the value and ensure the quality of emergency care delivered to older adults while more fully addressing their complex underlying physical, social, cognitive, and situational needs. Developing models of geriatric emergency care, including some that are already in use at dedicated geriatric EDs, incorporate a variety of physical, procedural, and staffing changes. Among the options for "geriatricizing" emergency care are approaches that may eliminate the need for an ED visit, such as telemedicine; for initial hospitalization, such as patient observation units; and for rehospitalization, such as comprehensive discharge planning. By transforming their current safety-net role to becoming a partner in care coordination, EDs have the opportunity to become better integrated into the broader health care system, improve patient health outcomes, contribute to optimizing the health care system, and reduce overall costs of care-keys to improving emergency care for patients of all ages.
Related JoVE Video
An Evidence-based Guideline for Pediatric Prehospital Seizure Management Using GRADE Methodology.
Prehosp Emerg Care
PUBLISHED: 12-03-2013
Show Abstract
Hide Abstract
Abstract Objective. The objective of this guideline is to recommend evidence-based practices for timely prehospital pediatric seizure cessation while avoiding respiratory depression and seizure recurrence. Methods. A multidisciplinary panel was chosen based on expertise in pediatric emergency medicine, prehospital medicine, and/or evidence-based guideline development. The panel followed the National Prehospital EBG Model using the GRADE methodology to formulate questions, retrieve evidence, appraise the evidence, and formulate recommendations. The panel members initially searched the literature in 2009 and updated their searches in 2012. The panel finalized a draft of a patient care algorithm in 2012 that was presented to stakeholder organizations to gather feedback for necessary revisions. Results. Five strong and ten weak recommendations emerged from the process; all but one was supported by low or very low quality evidence. The panel sought to ensure that the recommendations promoted timely seizure cessation while avoiding respiratory depression and seizure recurrence. The panel recommended that all patients in an active seizure have capillary blood glucose checked and be treated with intravenous (IV) dextrose or intramuscular (IM) glucagon if <60 mg/dL (3 mmol/L). The panel also recommended that non-IV routes (buccal, IM, or intranasal) of benzodiazepines (0.2 mg/kg) be used as first-line therapy for status epilepticus, rather than the rectal route. Conclusions. Using GRADE methodology, we have developed a pediatric seizure guideline that emphasizes the role of capillary blood glucometry and the use of buccal, IM, or intranasal benzodiazepines over IV or rectal routes. Future research is needed to compare the effectiveness and safety of these medication routes.
Related JoVE Video
The Development of Evidence-based Prehospital Guidelines Using a GRADE-based Methodology.
Prehosp Emerg Care
PUBLISHED: 11-26-2013
Show Abstract
Hide Abstract
Abstract Background. The burgeoning literature in prehospital care creates an opportunity to improve care through evidence-based guidelines (EBGs). Previously, an established process for the creation of such guidelines and adoption and implementation at the local level was lacking. This has led to great variability in the content of prehospital protocols in different jurisdictions across the globe. Recently the Federal Interagency Committee on Emergency Medical Services (FICEMS) and the National EMS Advisory Council (NEMSAC) approved a National Prehospital Evidence-based Guideline Model Process for the development, implementation, and evaluation of EBGs. The Model Process recommends the use of established guideline development tools such as Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Objective. To describe the process of development of three prehospital EBGs using the National Prehospital EBG Model Process (EBG Model Process) and the GRADE EBG development tool. Methods. We conducted three unique iterations of the EBG Model Process utilizing the GRADE EBG development tool. The process involved 6 distinct and essential steps, including 1) assembling the expert panel and providing GRADE training; 2) defining the evidence-based guideline (EBG) content area and establishing the specific clinical questions to address in patient, intervention, comparison, and outcome (PICO) format; 3) prioritizing outcomes to facilitate systematic literature searches; 4) creating GRADE tables, or evidence profiles, for each PICO question; 5) vetting and endorsing GRADE evidence tables and drafting recommendations; and 6) synthesizing recommendations into an EMS protocol and visual algorithm. Feedback and suggestions for improvement were solicited from participants and relevant stakeholders in the process. Results. We successfully used the process to create three separate prehospital evidence-based guidelines, formatted into decision tree algorithms with levels of evidence and graded recommendations assigned to each decision point. However, the process revealed itself to be resource intensive, and most of the suggestions for improvement would require even more resource utilization. Conclusions. The National Prehospital EBG Model Process can be used to create credible, transparent, and usable prehospital evidence-based guidelines. We suggest that a centralized or regionalized approach be used to create and maintain a full set of prehospital EBGs as a means of optimizing resource use.
Related JoVE Video
Isolation of breast cancer and gastric cancer circulating tumor cells by use of an anti HER2-based microfluidic device.
Lab Chip
PUBLISHED: 11-07-2013
Show Abstract
Hide Abstract
Circulating tumor cells (CTCs) have emerged as a reliable source of tumor cells, and their concentration has prognostic implications. CTC capture offers real-time access to cancer tissue without the need of an invasive biopsy, while their phenotypic and molecular interrogation can provide insight into the biological changes of the tumor that occur during treatment. The majority of the CTC capture methods are based on EpCAM expression as a surface marker of tumor-derived cells. However, EpCAM protein expression levels can be significantly down regulated during cancer progression as a consequence of the process of epithelial to mesenchymal transition. In this paper, we describe a novel HER2 (Human Epidermal Receptor 2)-based microfluidic device for the isolation of CTCs from peripheral blood of patients with HER2-expressing solid tumors. We selected HER2 as an alternative to EpCAM as the receptor is biologically and therapeutically relevant in several solid tumors, like breast cancer (BC), where it is overexpressed in 30% of the patients and expressed in 90%, and gastric cancer (GC), in which HER2 presence is identified in more than 60% of the cases. We tested the performance of various anti HER2 antibodies in a panel of nine different BC cell lines with varying HER2 protein expression levels, using immunoblotting, confocal microscopy, live cells imaging and flow cytometry analyses. The antibody associated with the highest capture efficiency and sensitivity for HER2 expressing cells on the microfluidic device was the one that performed best in live cells imaging and flow cytometry assays as opposed to the fixed cell analyses, suggesting that recognition of the native conformation of the HER2 extracellular epitope on living cells was essential for specificity and sensitivity of CTC capture. Next, we tested the performance of the HER2 microfluidic device using blood from metastatic breast and gastric cancer patients. The HER2 microfluidic device exhibited CTC capture in 9/9 blood samples. Thus, the described HER2-based microfluidic device can be considered as a valid clinically relevant method for CTC capture in HER2 expressing solid cancers.
Related JoVE Video
High-intensity telemedicine-enhanced acute care for older adults: an innovative healthcare delivery model.
J Am Geriatr Soc
PUBLISHED: 10-28-2013
Show Abstract
Hide Abstract
Accessing timely acute medical care is a challenge for older adults. This article describes an innovative healthcare model that uses high-intensity telemedicine services to provide rapid acute care for older adults without requiring them to leave their senior living community (SLC) residences. This program, based in a primary care geriatrics practice that cares for SLC residents, is designed to offer acute care through telemedicine for complaints that are felt to need attention before the next available outpatient visit but not to require emergency department (ED) resources. This option gives residents access to care in their residence. Measures used to evaluate the program include successful completion of telemedicine visits, satisfaction of residents and caregivers with telemedicine care, and site of care that would have been recommended had telemedicine been unavailable. During the first 2 years of the programs operation, 281 of 301 requested telemedicine visits were completed successfully. Twelve residents were sent to an ED for care after the telemedicine visit. Ninety-four percent of residents reported being satisfied or very satisfied with telemedicine care. Had telemedicine not been available, residents would have been sent to an ED (48.1%) or urgent care center (27.0%) or been scheduled for an outpatient visit (24.4%). The project demonstrated that high-intensity telemedicine services for acute illnesses are feasible and acceptable and can provide definitive care without requiring ED or urgent care use. Continuation of the program will require evaluation demonstrating equal or better resident-level outcomes and the development of sustainable business models.
Related JoVE Video
Capecitabine in the treatment of esophageal and gastric cancers.
Expert Opin Investig Drugs
PUBLISHED: 10-04-2013
Show Abstract
Hide Abstract
Fluoropyrimidine therapy has been a mainstay in the treatment of cancers of the esophagus and stomach for nearly half of a century in the form of intravenous 5-fluorouracil. Capecitabine , an oral fluoropyrimidine precursor, was first approved in 2001 for the treatment of metastatic colon cancer and may be used interchangeably with parenteral 5-FU in the treatment of upper gastrointestinal (GI) cancers.
Related JoVE Video
Prognostic role of lemur tyrosine kinase-3 germline polymorphisms in adjuvant gastric cancer in Japan and the United States.
Mol. Cancer Ther.
PUBLISHED: 08-05-2013
Show Abstract
Hide Abstract
Lemur tyrosine kinase-3 (LMTK3) was recently identified as an estrogen receptor (ER)-? modulator related to endocrine therapy resistance, and its polymorphisms rs9989661 (T>C) T/T genotype and rs8108419 (G>A) G/G or A/G genotype predicted improved outcomes in breast cancer. Because different predominant ER distributions link to breast and gastric cancer and little is known of the prognostic role of LMTK3 in gastric cancer, this study was carried out to clarify the prognostic role of these polymorphisms in gastric cancer. One-hundred and sixty-nine Japanese and 137 U.S. patients with localized gastric adenocarcinoma were enrolled. Genomic DNA was extracted from blood or tissue, and all samples were analyzed by PCR-based direct DNA sequencing. Overall, these polymorphisms were not associated with survival in both cohorts. When gender was considered, in multivariate analysis, harboring rs9989661 T/T genotype was associated with disease-free survival [HR, 4.37; 95% confidence interval (CI), 2.08-9.18; P < 0.0001] and overall survival (OS; HR, 3.69; 95% CI, 1.65-8.24; P = 0.0014) in the Japanese males and time to recurrence (HR, 7.29; 95% CI, 1.07-49.80; P = 0.043) in the U.S. females. Meanwhile, harboring rs8108419 G/G genotype was associated with OS in the Japanese females (HR, 3.04; 95% CI, 1.08-8.56; P = 0.035) and the U.S. males (HR, 3.39; 95% CI, 1.31-8.80; P = 0.012). The prognostic role of these polymorphisms may be negative in gastric cancer. These findings suggest that the estrogen pathway may play a prognostic role in patients with gastric cancer but this may be dependent on the regional differences both in physiology and genetic alterations of gastric cancer.
Related JoVE Video
Met, IGF1R, and other new targets in upper GI malignancies.
Curr Treat Options Oncol
PUBLISHED: 07-23-2013
Show Abstract
Hide Abstract
Upper gastrointestinal (GI) malignancies comprise some of the most aggressive human cancers. Expanding knowledge of molecular mechanisms is finally translating into clinical application, and this has occurred at a relatively rapid rate in the past several years. However, despite recent advances in targeted therapies in upper GI cancers our overall success with targeted therapeutics in this disease area remains dismal. This statement is particularly troubling given some sobering facts: upper GI malignancies are prevalent as well as aggressive with a high morbidity and mortality. Esophagus and gastric cancer combined have an annual global incidence of over 1.2 million new cases annually while median survival is less than 1 year for most patients with metastatic disease. Progress has been limited due to several factors including: disease heterogeneity and variance of phenotype across the globe, clinical trial design strategies that have not yet incorporated selective mechanisms to afford individualized matching of drug to tumor molecular profile and last, a lack of validated predictive markers. Nevertheless there is evidence that many targeted agents can be administered safely at doses that achieve the required effect at the protein level. Several drugs that have negative early trial results can be potentially vital therapeutic agents if patient selection is appropriate.
Related JoVE Video
Structural and thermodynamic basis of (+)-?-pinene binding to human cytochrome P450 2B6.
J. Am. Chem. Soc.
PUBLISHED: 07-03-2013
Show Abstract
Hide Abstract
Despite recent advances in atomic-level understanding of drug and inhibitor interactions with human cytochromes P450, the decades-old questions of chemical and structural determinants of hydrocarbon binding are still unanswered. (+)-?-Pinene is a monoterpene hydrocarbon that is widely distributed in the environment and a potent P450 2B inhibitor. Therefore, a combined biophysical and structural analysis of human P450 2B6 interactions with (+)-?-pinene was undertaken to elucidate the basis of the very high affinity binding. Binding of (+)-?-pinene to the P450 active site was demonstrated by a Type I spectral shift. Thermodynamics of ligand binding were explored using isothermal titration calorimetry and compared to those of P450 2A6, which is much less flexible than 2B6 based on comparison of multiple X-ray crystal structures. Consistent with expectation, entropy is the major driving force for hydrocarbon binding to P450 2A6, as evidenced by the calorimetric results. However, formation of the 2B6-(+)-?-pinene complex has a significant enthalpic component. A 2.0 Å resolution crystal structure of this enzyme-ligand complex reveals that the highly plastic 2B6 utilizes previously unrecognized rearrangements of protein motifs. The results indicate that the specific components of enthalpic contribution to ligand binding are closely tied to the degree of enzyme flexibility.
Related JoVE Video
Unanswered questions in the management of gastroesophageal junction adenocarcinoma.
Am Soc Clin Oncol Educ Book
PUBLISHED: 05-30-2013
Show Abstract
Hide Abstract
Patients with gastroesophageal junction (GEJ) adenocarcinoma have multiple treatment options; however, are victims of lack of consensus and wide variation in treatment, sometimes within the same hospital. While there is a consensus that surgery alone is inadequate for locally advanced disease, locoregional treatment has become the point for debate. Only in 2010 was the reclassification of GEJ cancers as esophageal cancers. Treatment options remain as varied as the classification of GEJ cancers: preoperative chemoradiotherapy, definitive chemoradiation, perioperative chemotherapy, and resection followed by postoperative chemoradiation. Several studies have examined the varying treatment paradigms; however, many fall short due to methodology or sample size. The MAGIC study determined perioperative chemotherapy to be an acceptable standard treatment option for patients with gastric cancer, althouth a significant portion of enrolled patients had distal esophageal and GEJ adenocarcinoma. The CROSS study concluded combination chemotherapy and radiation before resection beneficial. Preoperative therapy in cases of GEJ is beneficial for survival, but not as much impact is seen as in esophageal SCC, which exhibits an increased sensitivity to CRT. There is concurrence with two phase III studies from Japan and Korea on the role of adjuvant chemotherapy for gastric cancer. However, the applicability of these studies to GEJ adenocarcinoma remains a question, especially with the significantly different epidemiology of increased proximal and GEJ tumors in the West compared to Asia. To move forward with this increasingly prevalent disease, we will need to do more than understand the multiple treatment paradigms-we will need to select a strategy and examine it.
Related JoVE Video
Dural arteriovenous fistulas associated with benign meningeal tumors.
Acta Neurochir (Wien)
PUBLISHED: 05-23-2013
Show Abstract
Hide Abstract
Dural arteriovenous fistulas (dAVFs) are usually idiopathic lesions. While individual case reports have documented the occurrence of dAVFs in conjunction with benign meningeal tumors, a detailed characterization of this association is lacking. The objective of this study was to critically examine the relationship between benign meningeal tumors and dAVFs.
Related JoVE Video
A structural snapshot of CYP2B4 in complex with paroxetine provides insights into ligand binding and clusters of conformational states.
J. Pharmacol. Exp. Ther.
PUBLISHED: 04-30-2013
Show Abstract
Hide Abstract
An X-ray crystal structure of CYP2B4 in complex with the drug paroxetine [(3S,4R)-3-[(2H-1,3-benzodioxol-5-yloxy)methyl]-4-(4-fluorophenyl)piperidine] was solved at 2.14 Å resolution. The structure revealed a conformation intermediate to that of the recently solved complex with amlodipine and that of the more compact complex with 4-(4-chlorophenyl)imidazole in terms of the placement of the F-G cassette. Moreover, comparison of the new structure with 15 previously solved structures of CYP2B4 revealed some new insights into the determinants of active-site size and shape. The 2B4-paroxetine structure is nearly superimposable on a previously solved closed structure in a ligand-free state. Despite the overall conformational similarity among multiple closed structures, the active-site cavity volume of the paroxetine complex is enlarged. Further analysis of the accessible space and binding pocket near the heme reveals a new subchamber that resulted from the movement of secondary structural elements and rearrangements of active-site side chains. Overall, the results from the comparison of all 16 structures of CYP2B4 demonstrate a cluster of protein conformations that were observed in the presence or absence of various ligands.
Related JoVE Video
Does EMS perceived anatomic injury predict trauma center need?
Prehosp Emerg Care
PUBLISHED: 04-29-2013
Show Abstract
Hide Abstract
Our objective was to determine the predictive value of the anatomic step of the 2011 Field Triage Decision Scheme for identifying trauma center need.
Related JoVE Video
Are readmission rates on a neurosurgical service indicators of quality of care?
J. Neurosurg.
PUBLISHED: 04-26-2013
Show Abstract
Hide Abstract
The goal of this study was to examine the reasons for early readmissions within 30 days of discharge to a major academic neurosurgical service.
Related JoVE Video
A case report of trastuzumab dose in gastric cancer.
J Gastrointest Oncol
PUBLISHED: 04-25-2013
Show Abstract
Hide Abstract
Trastuzumab (Herceptin®, F. Hoffman-La Roche) is now approved for the treatment of metastatic HER2-positive gastric cancer based on the improved survival observed on the phase III Trastuzumab for Gastric Adenocarcinoma (ToGA) study. Standard dosing of trastuzumab is currently extrapolated from breast cancer data: a 3-week schedule (8 mg/kg load, 6 mg/kg q 3 weeks) or a weekly schedule (4 mg/kg load, 2 mg/kg q week).
Related JoVE Video
Voice outcomes from subligamentous cordectomy for early glottic cancer.
Ann. Otol. Rhinol. Laryngol.
PUBLISHED: 04-13-2013
Show Abstract
Hide Abstract
We evaluated the voice and vocal fold pliability outcomes of European Laryngological Society (ELS) deep type I (subepithelial) and type II (subligamentous) cordectomies for early glottic cancer.
Related JoVE Video
Assessment of phonomicrosurgical training in otolaryngology residencies: a resident survey.
Laryngoscope
PUBLISHED: 04-08-2013
Show Abstract
Hide Abstract
The primary objective of this study is to assess the adequacy of clinical and laboratory-based phonomicrosurgical training in otolaryngology residency programs using a self-report survey. The study aims to establish whether there is a need and desire for focused surgical training in phonomicrosurgery.
Related JoVE Video
Prospective pilot derivation of a decision tool for children at low risk for testicular torsion.
Acad Emerg Med
PUBLISHED: 03-23-2013
Show Abstract
Hide Abstract
The purpose of this study was to derive a pilot clinical decision tool with 100% negative predictive value for testicular torsion based on prospectively collected data in children with acute scrotal pain.
Related JoVE Video
Phase II study evaluating 2 dosing schedules of oral foretinib (GSK1363089), cMET/VEGFR2 inhibitor, in patients with metastatic gastric cancer.
PLoS ONE
PUBLISHED: 03-14-2013
Show Abstract
Hide Abstract
The receptors for hepatocyte and vascular endothelial cell growth factors (MET and VEGFR2, respectively) are critical oncogenic mediators in gastric adenocarcinoma. The purpose is to examine the safety and efficacy of foretinib, an oral multikinase inhibitor targeting MET, RON, AXL, TIE-2, and VEGFR2 receptors, for the treatment of metastatic gastric adenocarcinoma.
Related JoVE Video
A qualitative evaluation of a telemedicine-enhanced emergency care program for older adults.
J Am Geriatr Soc
PUBLISHED: 03-01-2013
Show Abstract
Hide Abstract
To document the experiences of patients, their caregivers, healthcare personnel, and staff members with a program that provides telemedicine-enhanced emergency care to older adults residing in senior living communities (SLCs) and to delineate perceived barriers and facilitators.
Related JoVE Video
Potential of telemedicine to provide acute medical care for adults in senior living communities.
Acad Emerg Med
PUBLISHED: 02-15-2013
Show Abstract
Hide Abstract
Older adults dwelling in senior living communities (SLCs) often experience barriers to medical care when they experience acute illness. The potential of telemedicine as a substitute for standard routes of evaluating and caring for individuals with acute illness (e.g., in-person or telephone-based interactions with primary care providers and emergency department [ED] visits) was explored in this study.
Related JoVE Video
Using health services research to meet ACGME resident research requirements.
Acad Radiol
PUBLISHED: 01-08-2013
Show Abstract
Hide Abstract
Health services research is a field of research that crosses many disciplines. It represents a novel way to address the Accreditation Council for Graduate Medical Education requirements for scholarly activity of residents and faculty in academic radiology departments. In addition to meeting training requirements, it offers future radiologists the opportunity to develop skills that will be essential as we transition from a volume based health care delivery system to an outcome based delivery system. This report introduces examples of health services research projects and the types of data resources that are available to facilitate such projects.
Related JoVE Video
X-ray crystal structure of the cytochrome P450 2B4 active site mutant F297A in complex with clopidogrel: insights into compensatory rearrangements of the binding pocket.
Arch. Biochem. Biophys.
PUBLISHED: 01-04-2013
Show Abstract
Hide Abstract
Prior X-ray crystal structures of cytochrome P450 2B4 revealed the pivotal role of rearrangement of the side chains of residues F206 and F297 in the active site in accommodating various inhibitors or substrates. To explore the role of these residues, 2B4 F206A and F297A were created by site-directed mutagenesis and characterized functionally. The structure of F297A with clopidogrel demonstrated the reorientation of the ligand such that the methyl ester group is oriented toward the heme, whereas the thiophene moiety now extends to the additional void in the F297A mutant. Most interestingly, movement of the I helix and several amino acid side chains within the active site was observed in apparent response to the altered binding orientation. Results of flexible docking using the 2B4 wild type or the F297A-virtual mutant positioned either the thiophene or chlorophenyl group closer to heme. However, docking of clopidogrel using the real F297A mutant or a virtual mutant with the I-helix re-positioned oriented clopidogrel preferentially with either the methyl ester or the chlorophenyl group closest to heme. The study provides insight into how the altered active site adapts to accommodate and interact with the substrate in a distinct orientation while maintaining the overall closed protein conformation.
Related JoVE Video
Potent mechanism-based inactivation of cytochrome P450 2B4 by 9-ethynylphenanthrene: implications for allosteric modulation of cytochrome P450 catalysis.
Biochemistry
PUBLISHED: 01-04-2013
Show Abstract
Hide Abstract
The mechanism-based inactivation of cytochrome P450 2B4 (CYP2B4) by 9-ethynylphenanthrene (9EP) has been investigated. The partition ratio and k(inact) are 0.2 and 0.25 min(-1), respectively. Intriguingly, the inactivation exhibits sigmoidal kinetics with a Hill coefficient of 2.5 and an S(50) of 4.5 ?M indicative of homotropic cooperativity. Enzyme inactivation led to an increase in mass of the apo-CYP2B4 by 218 Da as determined by electrospray ionization liquid chromatography and mass spectrometry, consistent with covalent protein modification. The modified CYP2B4 was purified to homogeneity and its structure determined by X-ray crystallography. The structure showed that 9EP is covalently attached to O? of Thr 302 via an ester bond, which is consistent with the increased mass of the protein. The presence of the bulky phenanthrenyl ring resulted in inward rotations of Phe 297 and Phe 206, leading to a compact active site. Thus, binding of another molecule of 9EP in the active site is prohibited. However, results from the quenching of 9EP fluorescence by unmodified or 9EP-modified CYP2B4 revealed at least two binding sites with distinct affinities, with the low-affinity site being the catalytic site and the high-affinity site on the protein periphery. Computer-aided docking and molecular dynamics simulations with one or two ligands bound revealed that the high-affinity site is situated at the entrance of a substrate access channel surrounded by the F helix, ?1-?2 loop, and ?4 loop and functions as an allosteric site to enhance the efficiency of activation of the acetylenic group of 9EP and subsequent covalent modification of Thr 302.
Related JoVE Video
Gastrointestinal cancer educational case series: management of metastatic adenocarcinoma of unknown primary origin in a Ph+ ALL survivor.
J Gastrointest Cancer
PUBLISHED: 12-13-2011
Show Abstract
Hide Abstract
Secondary malignancies and chronic end-organ sequelae are significant and steadily rising consequences of cancer therapy. The workup and management of a carcinoma of unknown primary must consider the patients clinical presentation, radiologic and pathologic findings, and comorbidities.
Related JoVE Video
Human epidermal growth factor receptor 2 testing in gastroesophageal cancer: correlation between immunohistochemistry and fluorescence in situ hybridization.
Arch. Pathol. Lab. Med.
PUBLISHED: 10-29-2011
Show Abstract
Hide Abstract
Patients with advanced gastroesophageal cancer have poor survival with current therapy. Human epidermal growth factor receptor 2 (HER2) represents a promising therapeutic target, but the optimal HER2 testing strategy is not yet defined.
Related JoVE Video
Emergency department visits by nursing home residents in the United States.
J Am Geriatr Soc
PUBLISHED: 10-12-2011
Show Abstract
Hide Abstract
To characterize emergency department (ED) use by nursing home residents in the United States.
Related JoVE Video
Reduced-force closed trocar entry technique: analysis of trocar insertion force using a mechanical force gauge.
JSLS
PUBLISHED: 09-10-2011
Show Abstract
Hide Abstract
Trocar insertion injury has a high morbidity, mortality, and cost. The purpose of this study was to compare standard trocar entry with our reduced-force closed trocar entry technique by measuring trocar insertion force using a mechanical force gauge.
Related JoVE Video
Does mechanism of injury predict trauma center need?
Prehosp Emerg Care
PUBLISHED: 08-30-2011
Show Abstract
Hide Abstract
To determine the predictive value of the mechanism-of-injury step of the American College of Surgeons Field Triage Decision Scheme for determining trauma center need.
Related JoVE Video
Structures of cytochrome P450 2B6 bound to 4-benzylpyridine and 4-(4-nitrobenzyl)pyridine: insight into inhibitor binding and rearrangement of active site side chains.
Mol. Pharmacol.
PUBLISHED: 08-29-2011
Show Abstract
Hide Abstract
The biochemical, biophysical, and structural analysis of the cytochrome P450 2B subfamily of enzymes has provided a wealth of information regarding conformational plasticity and substrate recognition. The recent X-ray crystal structure of the drug-metabolizing P450 2B6 in complex with 4-(4-chlorophenyl)imidazole (4-CPI) yielded the first atomic view of this human enzyme. However, knowledge of the structural basis of P450 2B6 specificity and inhibition has remained limited. In this study, structures of P450 2B6 were determined in complex with the potent inhibitors 4-benzylpyridine (4-BP) and 4-(4-nitrobenzyl)pyridine (4-NBP). Comparison of the present structures with the previous P450 2B6-4-CPI complex showed that reorientation of side chains of the active site residue Phe206 on the F-helix and Phe297 on the I-helix was necessary to accommodate the inhibitors. However, P450 2B6 does not require any major side chain rearrangement to bind 4-NBP compared with 4-BP, and the enzyme provides no hydrogen-bonding partners for the polar nitro group of 4-NBP within the hydrophobic active site. In addition, on the basis of these new structures, substitution of residue 172 with histidine as observed in the single nucleotide polymorphism Q172H and in P450 2B4 may contribute to a hydrogen bonding network connecting the E- and I-helices, thereby stabilizing active site residues on the I-helix. These results provide insight into the role of active site side chains upon inhibitor binding and indicate that the recognition of the benzylpyridines in the closed conformation structure of P450 2B6 is based solely on hydrophobicity, size, and shape.
Related JoVE Video
Bevacizumab in combination with chemotherapy as first-line therapy in advanced gastric cancer: a randomized, double-blind, placebo-controlled phase III study.
J. Clin. Oncol.
PUBLISHED: 08-15-2011
Show Abstract
Hide Abstract
The Avastin in Gastric Cancer (AVAGAST) trial was a multinational, randomized, placebo-controlled trial designed to evaluate the efficacy of adding bevacizumab to capecitabine-cisplatin in the first-line treatment of advanced gastric cancer.
Related JoVE Video
EMS Provider assessment of vehicle damage compared with assessment by a professional crash reconstructionist.
Prehosp Emerg Care
PUBLISHED: 08-04-2011
Show Abstract
Hide Abstract
To determine the accuracy of emergency medical services (EMS) provider assessments of motor vehicle damage when compared with measurements made by a professional crash reconstructionist.
Related JoVE Video
Endoscopically assisted versus open repair of sagittal craniosynostosis: the St. Louis Childrens Hospital experience.
J Neurosurg Pediatr
PUBLISHED: 08-03-2011
Show Abstract
Hide Abstract
This study investigated the differences in effectiveness and morbidity between endoscopically assisted wide-vertex strip craniectomy with barrel-stave osteotomies and postoperative helmet therapy versus open calvarial vault reconstruction without helmet therapy for sagittal craniosynostosis.
Related JoVE Video
Phase 2 trial of induction and concurrent chemoradiotherapy with weekly irinotecan and cisplatin followed by surgery for esophageal cancer.
Cancer
PUBLISHED: 07-08-2011
Show Abstract
Hide Abstract
Preoperative chemoradiation improves survival in esophageal and gastroesophageal junction (GEJ) cancer. We evaluated irinotecan and cisplatin as induction chemotherapy followed by concurrent chemoradiation in esophageal cancer.
Related JoVE Video
Resting-state activity in development and maintenance of normal brain function.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-27-2011
Show Abstract
Hide Abstract
One of the most intriguing recent discoveries concerning brain function is that intrinsic neuronal activity manifests as spontaneous fluctuations of the blood oxygen level-dependent (BOLD) functional MRI signal. These BOLD fluctuations exhibit temporal synchrony within widely distributed brain regions known as resting-state networks. Resting-state networks are present in the waking state, during sleep, and under general anesthesia, suggesting that spontaneous neuronal activity plays a fundamental role in brain function. Despite its ubiquitous presence, the physiological role of correlated, spontaneous neuronal activity remains poorly understood. One hypothesis is that this activity is critical for the development of synaptic connections and maintenance of synaptic homeostasis. We had a unique opportunity to test this hypothesis in a 5-y-old boy with severe epileptic encephalopathy. The child developed marked neurologic dysfunction in association with a seizure disorder, resulting in a 1-y period of behavioral regression and progressive loss of developmental milestones. His EEG showed a markedly abnormal pattern of high-amplitude, disorganized slow activity with frequent generalized and multifocal epileptiform discharges. Resting-state functional connectivity MRI showed reduced BOLD fluctuations and a pervasive lack of normal connectivity. The child underwent successful corpus callosotomy surgery for treatment of drop seizures. Postoperatively, the patients behavior returned to baseline, and he resumed development of new skills. The waking EEG revealed a normal background, and functional connectivity MRI demonstrated restoration of functional connectivity architecture. These results provide evidence that intrinsic, coherent neuronal signaling may be essential to the development and maintenance of the brains functional organization.
Related JoVE Video
Positive peritoneal cytology in patients with gastric cancer: natural history and outcome of 291 patients.
Indian J Surg Oncol
PUBLISHED: 06-26-2011
Show Abstract
Hide Abstract
Positive peritoneal cytology is a predictor of poor survival in patients with gastric cancer. Our aim is to more clearly define the natural history of this cohort.
Related JoVE Video
Analysis of incidence and clinical outcomes in patients with thromboembolic events and invasive exocrine pancreatic cancer.
Cancer
PUBLISHED: 05-12-2011
Show Abstract
Hide Abstract
Pancreatic adenocarcinoma is among the most common malignancies associated with thromboembolic events (TEs); however, reported incidence figures vary significantly and contain small patient cohorts. Pancreatic cancer-specific thrombosis studies examining the correlation between clinical variables, including thrombosis timing and the impact of thrombosis on survival, have not been reported.
Related JoVE Video
Use of movable high-field-strength intraoperative magnetic resonance imaging with awake craniotomies for resection of gliomas: preliminary experience.
Neurosurgery
PUBLISHED: 04-19-2011
Show Abstract
Hide Abstract
Awake craniotomy with electrocortical mapping and intraoperative magnetic resonance imaging (iMRI) are established techniques for maximizing tumor resection and preserving function, but there has been little experience combining these methodologies.
Related JoVE Video
High yield research opportunities in geriatric emergency medicine: prehospital care, delirium, adverse drug events, and falls.
J. Gerontol. A Biol. Sci. Med. Sci.
PUBLISHED: 04-17-2011
Show Abstract
Hide Abstract
Emergency services constitute crucial and frequently used safety nets for older persons, an emergency visit by a senior very often indicates high vulnerability for functional decline and death, and interventions via the emergency system have significant opportunities to change the clinical course of older patients who require its services. However, the evidence base for widespread employment of emergency system-based interventions is lacking. In this article, we review the evidence and offer crucial research questions to capitalize on the opportunity to optimize health trajectories of older persons seeking emergency care in four areas: prehospital care, delirium, adverse drug events, and falls.
Related JoVE Video
Molecular classification of gastric cancer: a new paradigm.
Clin. Cancer Res.
PUBLISHED: 03-23-2011
Show Abstract
Hide Abstract
Gastric cancer may be subdivided into 3 distinct subtypes--proximal, diffuse, and distal gastric cancer--based on histopathologic and anatomic criteria. Each subtype is associated with unique epidemiology. Our aim is to test the hypothesis that these distinct gastric cancer subtypes may also be distinguished by gene expression analysis.
Related JoVE Video
MET expression and amplification in patients with localized gastric cancer.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 03-10-2011
Show Abstract
Hide Abstract
MET, the receptor for hepatocyte growth factor, has been proposed as a therapeutic target in gastric cancer. This study assessed the incidence of MET expression and gene amplification in tumors of Western patients with gastric cancer.
Related JoVE Video
Role of ¹?F 2-fluoro-2-deoxyglucose positron emission tomography in upper gastrointestinal malignancies.
World J. Gastroenterol.
PUBLISHED: 02-13-2011
Show Abstract
Hide Abstract
The role of whole-body FDG [((18)F) 2-fluoro-2-deoxyglucose] positron emission tomography (PET) scanning as an imaging modality in the management of patients with malignancy has evolved enormously over the past two decades. FDG-PET has demonstrated significant efficacy in the staging, prognostication and detection of occult metastatic disease in malignancies of the gastrointestinal tract, in addition to assessment of the response to cytotoxic chemotherapy in a more timely manner than has traditionally been possible by more conventional imaging tools. The sensitivity and specificity of FDG-PET for the detection and staging of malignancy depend not only on the site and size of the primary tumor and metastases, but also on histological cell type, reflecting underlying disparities in glucose metabolism. The metabolic response to neo-adjuvant chemotherapy or to chemo-radiotherapy in cancers of the gastro-esophageal junction or stomach has been demonstrated in several prospective studies to correlate significantly with both the histological tumor response to treatment and with consequent improvements in overall survival. This may offer a future paradigm of personalized treatment based on the PET response to chemotherapy. FDG-PET has been less successful in efforts to screen for and detect recurrent upper gastrointestinal malignancies, and in the detection of low volume metastatic peritoneal disease. Efforts to improve the accuracy of PET include the use of novel radiotracers such as ((18)F) FLT (3-deoxy-3-fluorothymidine) or (11)C-choline, or fusion PET-CT with concurrent high-resolution computed tomography. This review focuses on the role of FDG-PET scanning in staging and response assessment in malignancies of the upper gastrointestinal tract, specifically gastric, esophageal and pancreas carcinoma.
Related JoVE Video
Germline polymorphisms in genes involved in the CD44 signaling pathway are associated with clinical outcome in localized gastric adenocarcinoma.
Int. J. Cancer
PUBLISHED: 02-11-2011
Show Abstract
Hide Abstract
The cluster of differentiation 44 (CD44) signaling pathway is crucial in cancer-cell growth, invasion, proliferation and metastasis. CD44 is a transmembrane receptor for hyaluronan and osteopontin, and has recently attracted attention as a gastric cancer stem cell marker. Previous studies showed that polymorphisms in the CD44 gene can influence both human cancer survival and determine cellular response to cytotoxic chemotherapeutics. In addition, CD44 protein overexpression has been associated with poor prognosis in gastric adenocarcinoma (GA). We tested the hypothesis whether polymorphisms involved in the CD44 pathway will predict clinical outcome in patients with localized GA. Either blood or formalin-fixed paraffin-embedded (FFPE) tissues were obtained from 137 patients with localized GA at University of Southern California and Memorial Sloan-Kettering Cancer Center medical facilities. DNA was isolated and polymorphisms within the CD44 pathway were determined by PCR-RFLP technique. In univariate analysis CD44 rs187116 and CD44 rs7116432 were significantly associated with time to tumor recurrence (TTR) and overall survival (OS). After adjusting for covariates, patients harboring at least one G allele of CD44 rs187116 remained significantly associated with TTR (adjusted p=0.009) and OS (adjusted p=0.045). Further, patients harboring CD44 T-A haplotype were at the lowest risk of developing tumor recurrence (HR: 0.255; 95% CI: 0.11-0.591; adjusted p=0.001) and death (HR 0.198; 95% CI: 0.07-0.563; adjusted p=0.002). These results provide the first evidence that CD44 polymorphisms predict clinical outcome in patients with localized GA. This may help to identify localized GA patients at high risk for tumor recurrence.
Related JoVE Video
Racial differences in mortality among patients with acute ischemic stroke: an observational study.
Ann. Intern. Med.
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
Black patients are commonly believed to have higher stroke mortality. However, several recent studies have reported better survival in black patients with stroke.
Related JoVE Video
Depression and cognitive impairment in older adult emergency department patients: changes over 2 weeks.
J Am Geriatr Soc
PUBLISHED: 01-28-2011
Show Abstract
Hide Abstract
To evaluate older adult emergency department (ED) patients for depression and cognitive impairment and to re-evaluate those findings 2 weeks later.
Related JoVE Video
Association between stroke center hospitalization for acute ischemic stroke and mortality.
JAMA
PUBLISHED: 01-27-2011
Show Abstract
Hide Abstract
Although stroke centers are widely accepted and supported, little is known about their effect on patient outcomes.
Related JoVE Video
Factors associated with emergency department use among the rural elderly.
J Rural Health
PUBLISHED: 01-06-2011
Show Abstract
Hide Abstract
Emergency Department (ED) use among the rural elderly may present a different pattern from the urban elderly, thus requiring different policy initiatives. However, ED use among the rural elderly has seldom been studied and is little understood.
Related JoVE Video
Phase II study of modified docetaxel, cisplatin, and fluorouracil with bevacizumab in patients with metastatic gastroesophageal adenocarcinoma.
J. Clin. Oncol.
PUBLISHED: 12-28-2010
Show Abstract
Hide Abstract
To evaluate the safety and efficacy of a modified administration schedule of docetaxel, cisplatin, and fluorouracil (mDCF) with bevacizumab in patients with advanced gastroesophageal malignancies.
Related JoVE Video
Blood transfusion prediction in patients undergoing major head and neck surgery with free-flap reconstruction.
Arch. Otolaryngol. Head Neck Surg.
PUBLISHED: 12-22-2010
Show Abstract
Hide Abstract
to develop a clinically useful perioperative blood transfusion prediction model for patients undergoing a major head and neck surgical procedure requiring free-flap reconstruction.
Related JoVE Video
Decision making for the extent of thyroidectomy in the patient with atypical cytologic results.
Arch. Otolaryngol. Head Neck Surg.
PUBLISHED: 12-22-2010
Show Abstract
Hide Abstract
to identify additional preoperative factors that could reliably be used to aid in determining the appropriate extent of thyroidectomy.
Related JoVE Video
Comparison of in vitro metabolism of ticlopidine by human cytochrome P450 2B6 and rabbit cytochrome P450 2B4.
Drug Metab. Dispos.
PUBLISHED: 12-14-2010
Show Abstract
Hide Abstract
A recent X-ray crystal structure of a rabbit cytochrome P450 2B4 (CYP2B4)-ticlopidine complex indicated that the compound could be modeled with either the thiophene or chlorophenyl group oriented toward the heme prosthetic group. Subsequent NMR relaxation and molecular docking studies suggested that orientation with the chlorophenyl ring closer to the heme was the preferred one. To evaluate the predictive value of these findings, the oxidation of ticlopidine by reconstituted CYP2B4 was studied and compared with CYP2B6, in which the thiophene portion of the molecule likely orients toward the heme. In vitro incubation of ticlopidine with both enzymes yielded the same set of metabolites: 7-hydroxyticlopidine (M1), 2-oxoticlopidine (M2), 5-(2-chlorobenzyl)thieno[3,2-c]pyridin-5-ium metabolite (M3), 5-(2-chlorobenzyl)thieno[3,2-c]pyridin-5-ium metabolite (M4), ticlopidine N-oxide (M5), and ticlopidine S-oxide dimer, a dimerization product of ticlopidine S-oxide (M6). The rates of metabolite formation deviated markedly from linearity with time, consistent with the known inactivation of CYP2B6 by ticlopidine. Fitting to a first-order equation yielded similar rate constants (k(obs)) for both enzymes. However, the amplitude (R(max)) of M1 and M6 formation was 4 to 5 times higher for CYP2B6 than CYP2B4, indicating a greater residence time of ticlopidine with its thiophene ring closer to heme in CYP2B6. In contrast, CYP2B4 formed M4 and M5 in more abundance than CYP2B6, indicating an alternate orientation. Overall, the results suggest that the preferential orientation of ticlopidine in the active site of CYP2B4 predicted by X-ray crystallography and NMR studies is unproductive and that ticlopidine likely reorients within CYP2B4 to a more productive mode.
Related JoVE Video
A novel emergency medical services-based program to identify and assist older adults in a rural community.
J Am Geriatr Soc
PUBLISHED: 11-09-2010
Show Abstract
Hide Abstract
Rural-dwelling older adults experience unique challenges related to accessing medical and social services. This article describes the development, implementation, and experience of a novel, community-based program to identify rural-dwelling older adults with unmet medical and social needs that leveraged the existing emergency medical services (EMS) system. The program specifically included geriatrics training for EMS providers; screening of older adult EMS patients for falls, depression, and medication management strategies by EMS providers; communication of EMS findings to community-based case managers; in-home evaluation by case managers; and referral to community resources for medical and social interventions. Measures used to evaluate the program included patient needs identified by EMS or the in-home assessment, referrals provided to patients, and patient satisfaction. EMS screened 1,231 of 1,444 visits to older patients (85%). Of those receiving specific screens, 45% had fall-related, 69% medication management-related, and 20% depression-related needs identified. One hundred and seventy-one eligible EMS patients who could be contacted accepted the in-home assessment. Of the 153 individuals completing the assessment, 91% had identified needs and received referrals or interventions. This project demonstrated that screening by EMS during emergency care for common geriatric syndromes and linkage to case managers is feasible in this rural community, although many will refuse the services. Further patient evaluations by case managers, with subsequent interventions by existing service providers as required, can facilitate the needed linkages between vulnerable rural-dwelling older adults and needed community-based social and medical services.
Related JoVE Video
Comparison of the 1999 and 2006 trauma triage guidelines: where do patients go?
Prehosp Emerg Care
PUBLISHED: 11-05-2010
Show Abstract
Hide Abstract
In 2006, the Centers for Disease Control and Prevention (CDC) released a revised Field Triage Decision Scheme. It is unknown how this modified scheme will affect the number of patients identified by emergency medical services (EMS) for transport to a trauma center.
Related JoVE Video
Prevalence of depression and cognitive impairment in older adult emergency medical services patients.
Prehosp Emerg Care
PUBLISHED: 10-26-2010
Show Abstract
Hide Abstract
To characterize the proportion of older adult emergency department (ED) patients with depression or cognitive impairment. To compare the prevalences of depression or cognitive impairment among ED patients arriving via emergency medical services (EMS) and those arriving via other modes.
Related JoVE Video
Plasticity of cytochrome P450 2B4 as investigated by hydrogen-deuterium exchange mass spectrometry and X-ray crystallography.
J. Biol. Chem.
PUBLISHED: 09-28-2010
Show Abstract
Hide Abstract
Crystal structures of the xenobiotic metabolizing cytochrome P450 2B4 have demonstrated markedly different conformations in the presence of imidazole inhibitors or in the absence of ligand. However, knowledge of the plasticity of the enzyme in solution has remained scant. Thus, hydrogen-deuterium exchange mass spectrometry (DXMS) was utilized to probe the conformations of ligand-free P450 2B4 and the complex with 4-(4-chlorophenyl)imidazole (4-CPI) or 1-biphenyl-4-methyl-1H-imidazole (1-PBI). The results of DXMS indicate that the binding of 4-CPI slowed the hydrogen-deuterium exchange rate over the B- and C-helices and portions of the F-G-helix cassette compared with P450 2B4 in the absence of ligands. In contrast, there was little difference between the ligand-free and 1-PBI-bound exchange sets. In addition, DXMS suggests that the ligand-free P450 2B4 is predominantly open in solution. Interestingly, a new high resolution structure of ligand-free P450 2B4 was obtained in a closed conformation very similar to the 4-CPI complex. Molecular dynamics simulations performed with the closed ligand-free structure as the starting point were used to probe the energetically accessible conformations of P450 2B4. The simulations were found to equilibrate to a conformation resembling the 1-PBI-bound P450 2B4 crystal structure. The results indicate that conformational changes observed in available crystal structures of the promiscuous xenobiotic metabolizing cytochrome P450 2B4 are consistent with its solution structural behavior.
Related JoVE Video
Characteristics and acute care use patterns of patients in a senior living community medical practice.
J Am Med Dir Assoc
PUBLISHED: 09-09-2010
Show Abstract
Hide Abstract
Primary care medical practices dedicated to the needs of older adults who dwell in independent and assisted living residences in senior living communities (SLCs) have been developed. To date, the demographic and acute medical care use patterns of patients in these practices have not been described.
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.