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.
Surgical Site Infection and Timing of Prophylactic Antibiotics for Appendectomy.
Surg Infect (Larchmt)
PUBLISHED: 11-18-2014
Show Abstract
Hide Abstract
Abstract Background: Pre-operative prophylactic antibiotics may decrease the frequency of surgical site infection after appendectomy. However, the optimal timing for administration of pre-operative prophylactic antibiotics is unknown. The purpose of this study was to evaluate the effect of timing of prophylactic antibiotics on the frequency of surgical site infection after appendectomy. Methods: Medical records were reviewed retrospectively for 577 consecutive patients who had appendectomy for acute appendicitis from 2006 to 2009. Quality assurance guidelines for timing of prophylactic antibiotics before the skin incision were changed from 0 to 30?min before the skin incision (before June 2008) to 30 to 60?min before the skin incision (after June 2008). Results: Surgical site infection occurred in 28 patients (4.9%). There was no difference in frequency of surgical site infection with different timing of pre-operative prophylactic antibiotic (pre-operative time 0 to 30?min: 9 infections [3.6%]; 31 to 60?min: 13 infections [5.4%]; 61 to 120?min: 5 infections [7.0%]; >120?min: 1 infection [6.6%]). Multivariable analysis showed that surgical site infection was associated significantly with medical comorbidity but not perforated appendicitis. Conclusions: The frequency of surgical site infection was independent of timing of preoperative prophylactic antibiotics but was associated with the presence of medical comorbidity.
Related JoVE Video
Low cord blood vitamin D levels are associated with increased milk sensitization in early childhood.
Pediatr Allergy Immunol
PUBLISHED: 11-13-2014
Show Abstract
Hide Abstract
The association between vitamin D status at birth and allergen sensitizations is uncertain. The aim of this study was to investigate the relationship of cord blood vitamin D status with allergen sensitizations and the development of atopic diseases in early childhood.
Related JoVE Video
Population-based cohort study on the risk of pneumonia in patients with non-traumatic intracranial haemorrhage who use proton pump inhibitors.
BMJ Open
PUBLISHED: 11-12-2014
Show Abstract
Hide Abstract
This nationwide cohort study investigated the association between proton pump inhibitor (PPI) usage and the risk of pneumonia in patients with non-traumatic intracranial haemorrhage (ICH).
Related JoVE Video
EGFR mutation testing practices within the Asia Pacific region: Results of a multicenter diagnostic survey.
J Thorac Oncol
PUBLISHED: 11-08-2014
Show Abstract
Hide Abstract
The efficacy of EGFR tyrosine kinase inhibitors in EGFR mutation-positive NSCLC patients necessitates accurate, timely testing. Although EGFR mutation testing has been adopted by many laboratories in Asia, data are lacking on the proportion of NSCLC patients tested in each country, and the most commonly used testing methods.
Related JoVE Video
Does chronic rhinosinusitis increase the risk of lung cancer? A population cohort study.
Clin Respir J
PUBLISHED: 10-27-2014
Show Abstract
Hide Abstract
Chronic rhinosinusitis is one of the most common chronic inflammatory diseases of the upper airway. A previous study of chronic rhinosinusitis and the risks of lung cancer was based on a self-reported questionnaire concerning rhinosinusitis. Population-based cohort studies of the correlation between chronic rhinosinusitis and the adenocarcinoma subtype of lung cancer have been limited.
Related JoVE Video
Clinical characteristics and treatment outcomes of lung adenocarcinomas with discrepant EGFR mutation testing results derived from PCR-direct sequencing and real-time PCR-based assays.
J Thorac Oncol
PUBLISHED: 09-27-2014
Show Abstract
Hide Abstract
Detection of epidermal growth factor receptor (EGFR) mutation has become the most critical molecular test in managing patients with advanced lung adenocarcinoma. Whether patients with discrepant EGFR mutation results determined by low- and high-sensitivity methods have different clinical outcomes with EGFR tyrosine kinase inhibitor (TKI) treatment needs to be further evaluated.
Related JoVE Video
High-altitude pulmonary edema can be prevented by heat shock protein 70-mediated hyperbaric oxygen preconditioning.
J Trauma Acute Care Surg
PUBLISHED: 09-25-2014
Show Abstract
Hide Abstract
The primary goal of this study was to test whether high-altitude exposure (HAE of 9.7% O2 at 0.47 absolute atmosphere [ATA] for 3 days) was capable of increasing lung edema, neutrophil, and hemorrhage scores as well as decreasing lung levels of both aquaporin 1 (AQP1) and AQP5 proteins and messenger RNA (mRNA) expression in rats, with a secondary goal to test whether a preinduction of heat shock protein 70 (HSP70) by hyperbaric oxygen preconditioning (HBO2P of 100% O2 at 2.0 ATA for 1 hour per day for 5 consecutive days) attenuated the HAE-induced increased lung injury scores and decreased lung AQP1 and AQP5 protein and mRNA expressions.
Related JoVE Video
Pyridoxamine protects against mechanical defects in cardiac ageing in rats: studies on load dependence of myocardial relaxation.
Exp. Physiol.
PUBLISHED: 09-18-2014
Show Abstract
Hide Abstract
Our team demonstrated in the past that pyridoxamine attenuated arterial stiffening by targeting the pathogenic formation of glycated collagen cross-links in aged rats. Herein, we examined whether pyridoxamine therapy can protect against mechanical defects in myocardial relaxation by improving arterial wave properties and cardiac contractile performance in senescent animals. Fifteen-month-old male Fisher 344 rats were treated daily with pyridoxamine (1 g l(-1) in drinking water) for 5 months and compared with age-matched untreated control animals (20 months old). Arterial wave properties were characterized by wave transit time (?w) and wave reflection factor (Rf). We measured the contractile status of the myocardium in an intact heart as the left ventricular (LV) end-systolic elastance (Ees). Myocardial relaxation was described according to the time constant of the LV isovolumic pressure decay (?e). Pyridoxamine therapy prevented the age-associated prolongation in LV ?e and the diminished Ees in senescent rats. The drug also attenuated the age-related augmentation in afterload imposed on the heart, as evidenced by the increased ?w and decreased Rf. We found that the LV ?e was significantly influenced by both the arterial ?w and Rf (?e = 16.3902 + 8.3123 × Rf - 0.4739 × ?w; r = 0.7048, P < 0.005). In the meantime, the LV ?e and the LV Ees showed a significant inverse linear correlation (?e = 13.9807 - 0.0068 × Ees; r = 0.6451, P < 0.0005). All these findings suggested that long-term treatment with pyridoxamine might ameliorate myocardial relaxation rate, at least partly through its ability to enhance myocardial contractile performance, increase wave transit time and decrease wave reflection factor in aged rats.
Related JoVE Video
Chronic rhinosinusitis and the risk of nasopharyngeal cancer in a Taiwanese health study.
Am J Rhinol Allergy
PUBLISHED: 09-09-2014
Show Abstract
Hide Abstract
Although epidemiological and laboratory studies report that chronic inflammatory conditions contribute to the pathogenesis of cancer, it remains controversial whether chronic rhinosinusitis (CRS) results in nasopharyngeal cancer (NPC).
Related JoVE Video
Incidence, clinical characteristics and risk factors for adverse outcome in neonates with late-onset sepsis.
Pediatr. Infect. Dis. J.
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
Late-onset sepsis (LOS) is a common complication in the neonatal intensive care unit. We aimed to describe the epidemiology, clinical characteristics and risk factors for adverse outcome in neonates with LOS.
Related JoVE Video
Quantitative analysis of intrinsic skin aging in dermal papillae by in vivo harmonic generation microscopy.
Biomed Opt Express
PUBLISHED: 09-01-2014
Show Abstract
Hide Abstract
Chronological skin aging is associated with flattening of the dermal-epidermal junction (DEJ), but to date no quantitative analysis focusing on the aging changes in the dermal papillae (DP) has been performed. The aim of the study is to determine the architectural changes and the collagen density related to chronological aging in the dermal papilla zone (DPZ) by in vivo harmonic generation microscopy (HGM) with a sub-femtoliter spatial resolution. We recruited 48 Asian subjects and obtained in vivo images on the sun-protected volar forearm. Six parameters were defined to quantify 3D morphological changes of the DPZ, which we analyzed both manually and computationally to study their correlation with age. The depth of DPZ, the average height of isolated DP, and the 3D interdigitation index decreased with age, while DP number density, DP volume, and the collagen density in DP remained constant over time. In vivo high-resolution HGM technology has uncovered chronological aging-related variations in DP, and sheds light on real-time quantitative skin fragility assessment and disease diagnostics based on collagen density and morphology.
Related JoVE Video
Adoptive transfer of EBV specific CD8+ T cell clones can transiently control EBV infection in humanized mice.
PLoS Pathog.
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Epstein Barr virus (EBV) infection expands CD8+ T cells specific for lytic antigens to high frequencies during symptomatic primary infection, and maintains these at significant numbers during persistence. Despite this, the protective function of these lytic EBV antigen-specific cytotoxic CD8+ T cells remains unclear. Here we demonstrate that lytic EBV replication does not significantly contribute to virus-induced B cell proliferation in vitro and in vivo in a mouse model with reconstituted human immune system components (huNSG mice). However, we report a trend to reduction of EBV-induced lymphoproliferation outside of lymphoid organs upon diminished lytic replication. Moreover, we could demonstrate that CD8+ T cells against the lytic EBV antigen BMLF1 can eliminate lytically replicating EBV-transformed B cells from lymphoblastoid cell lines (LCLs) and in vivo, thereby transiently controlling high viremia after adoptive transfer into EBV infected huNSG mice. These findings suggest a protective function for lytic EBV antigen-specific CD8+ T cells against EBV infection and against virus-associated tumors in extra-lymphoid organs. These specificities should be explored for EBV-specific vaccine development.
Related JoVE Video
Can FESS combined with submucosal resection (SMR)/septoplasty reduce revision rate?
Otolaryngol Head Neck Surg
PUBLISHED: 08-21-2014
Show Abstract
Hide Abstract
Our study was designed to ascertain the outcomes of functional endoscopic sinus surgery (FESS) combined with submucosal resection (SMR)/septoplasty in reducing FESS revision rates.
Related JoVE Video
Ultrafast water dynamics at the interface of the polymerase-DNA binding complex.
Biochemistry
PUBLISHED: 08-15-2014
Show Abstract
Hide Abstract
DNA polymerases slide on DNA during replication, and the interface must be mobile for various conformational changes. The role of lubricant interfacial water is not understood. In this report, we systematically characterize the water dynamics at the interface and in the active site of a tight binding polymerase (pol ?) in its binary complex and ternary state using tryptophan as a local optical probe. Using femtosecond spectroscopy, we observed that upon DNA recognition the surface hydration water is significantly confined and becomes bound water at the interface, but the dynamics are still ultrafast and occur on the picosecond time scale. These interfacial water molecules are not trapped but are mobile in the heterogeneous binding nanospace. Combining our findings with our previous observation of ultrafast water motions at the interface of a loose binding polymerase (Dpo4), we conclude that the binding interface is dynamic and the water molecules in various binding clefts, channels, and caves are mobile and even fluid with different levels of mobility for loose or tight binding polymerases. Such a dynamic interface should be general to all DNA polymerase complexes to ensure the biological function of DNA synthesis.
Related JoVE Video
Multiple complexes of long aliphatic N-acyltransferases lead to synthesis of 2,6-diacylated/2-acyl-substituted glycopeptide antibiotics, effectively killing vancomycin-resistant enterococcus.
J. Am. Chem. Soc.
PUBLISHED: 07-25-2014
Show Abstract
Hide Abstract
Teicoplanin A2-2 (Tei)/A40926 is the last-line antibiotic to treat multidrug-resistant Gram-positive bacterial infections, e.g., methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE). This class of antibiotics is powered by the N-acyltransferase (NAT) Orf11*/Dbv8 through N-acylation on glucosamine at the central residue of Tei/A40926 pseudoaglycone. The NAT enzyme possesses enormous value in untapped applications; its advanced development is hampered largely due to a lack of structural information. In this report, we present eight high-resolution X-ray crystallographic unary, binary, and ternary complexes in order to decipher the molecular basis for NAT's functionality. The enzyme undergoes a multistage conformational change upon binding of acyl-CoA, thus allowing the uploading of Tei pseudoaglycone to enable the acyl-transfer reaction to take place in the occlusion between the N- and C-halves of the protein. The acyl moiety of acyl-CoA can be bulky or lengthy, allowing a large extent of diversity in new derivatives that can be formed upon its transfer. Vancomycin/synthetic acyl-N-acetyl cysteamine was not expected to be able to serve as a surrogate for an acyl acceptor/donor, respectively. Most strikingly, NAT can catalyze formation of 2-N,6-O-diacylated or C6?C2 acyl-substituted Tei analogues through an unusual 1,4-migration mechanism under stoichiometric/solvational reaction control, wherein selected representatives showed excellent biological activities, effectively counteracting major types (VanABC) of VRE.
Related JoVE Video
Type II diabetes mellitus is associated with a reduced risk of cholangiocarcinoma in patients with biliary tract diseases.
Int. J. Cancer
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
It has not yet been reported whether Type II diabetes mellitus (DM) is associated with an increased cholangiocarcinoma (CC) risk in patients with biliary tract diseases. We identified 123,050 patients concomitantly diagnosed with biliary tract diseases and DM between 1998 and 2010. The control cohort consisted of 122,721 individuals with biliary tract diseases but not DM. Both cohorts were followed-up until the end of 2010 to estimate the risk of CC. We also compared the risk of CC between DM and non-DM cohorts without biliary tract diseases. Overall, the incidence of CC was 21% lower among the DM patients than among the control patients (1.11 vs. 1.41 per 1,000 person-years). DM cohorts exhibited significantly reduced risks for both intrahepatic and extrahepatic CC. A multivariable Cox proportional hazards regression model was used, and the adjusted hazard ratio (HR) of CC was 0.74 (95% confidence interval [CI], 0.66-0.82) for the DM cohort in comparison with the control cohort. The age-specific data indicated that compared with the control patients, the adjusted HRs for the DM patients were significantly lower among patients 50-64 (adjusted HR?=?0.67; 95% CI?=?0.55-0.82) and 65-74 years old (adjusted HR?=?0.70; 95% CI, 0.59-0.84). Furthermore, DM was associated with a lower risk of CC among patients with biliary diseases, regardless of the presence of comorbidities and the status of cholecystectomy. In the patients without biliary tract diseases, DM is associated with significantly increased risk of CC (adjusted HR?=?1.58; 95% CI, 1.37-1.82).
Related JoVE Video
Physician-patient end-of-life care discussions: Correlates and associations with end-of-life care preferences of cancer patients-a cross-sectional survey study.
Palliat Med
PUBLISHED: 06-25-2014
Show Abstract
Hide Abstract
Honoring patients' treatment preferences is a key component of high-quality end-of-life care. Connecting clinical practices to patients' preferences requires effective communication. However, few cancer patients reported discussing end-of-life-care preferences with their physicians.
Related JoVE Video
Relationships of Circadian Rhythms and Physical Activity With Objective Sleep Parameters in Lung Cancer Patients.
Cancer Nurs
PUBLISHED: 06-20-2014
Show Abstract
Hide Abstract
Lung cancer patients undergo various treatments leading to sleep problems, rest-activity circadian rhythms disruption, and reduced levels of physical activity. It is important to understand the relationships among these variables. Appropriate interventions can possibly be implemented to improve sleep quality in lung cancer patients.
Related JoVE Video
Carbapenem-resistant-only Pseudomonas aeruginosa infection in patients formerly infected by carbapenem-susceptible strains.
Int. J. Antimicrob. Agents
PUBLISHED: 06-19-2014
Show Abstract
Hide Abstract
Pseudomonas aeruginosa isolates that were initially carbapenem-susceptible and later became selective carbapenem-resistant following antimicrobial therapy were identified from individual cases during the same hospitalisation. Cross-resistance to other ?-lactams was not found and their susceptibilities remained identical in consecutive isolates. Real-time quantitative reverse transcription PCR was performed to investigate the role of OprD, an outer membrane protein regulating the entry of carbapenems, in the appearance of carbapenem-resistant-only P. aeruginosa (CROPA). Fifteen paired isolates of carbapenem-susceptible P. aeruginosa (CS-PA) and CROPA were identified. All of the cases had carbapenem exposure history within 1 month before the appearance of CROPA (mean 10 days). Reduced OprD expression was found in 93% (14/15) of the isolates, suggesting that oprD inactivation was the major contributor to selective carbapenem resistance. Of the 14 cases with CROPA due to oprD mutation, 71% (10/14) were persistent infection, as genotype analysis revealed that their paired strains were isogenic; 29% (4/14) represented re-infections as they were heterogenic, suggesting that oprD-deficient CROPA existed in the hospital and that carbapenem selective pressure promoted its spread to patients. We conclude that CROPA may occur soon after the use of carbapenems to treat CS-PA infections and that oprD mutation is the major mechanism of resistance in CROPA. Restriction of empirical use of carbapenems by antibiotic stewardship is important to halt the occurrence of CROPA.
Related JoVE Video
Therapeutic Efficacy of Neuro AiD™ (MLC 601), a Traditional Chinese Medicine, in Experimental Traumatic Brain Injury.
J Neuroimmune Pharmacol
PUBLISHED: 06-05-2014
Show Abstract
Hide Abstract
Traumatic brain injury (TBI) causes increased release of several mediators from injured and dead cells and elicits microglial activation. Activated microglia change their morphology, migrate to injury sites, and release tumor necrosis factor-alpha (TNF-?) and others. In this study we used a controlled fluid percussion injury model of TBI in the rat to determine whether early (4 h post-injury) or late (4 days post-injury) treatment with MLC 601, a Traditional Chinese Medicine, would affect microglial activation and improve recovery. MLC 601 was chosen for this study because its herbal component MLC 901 was beneficial in treating TBI in rats. Herein, rats with induced TBI were treated with MLC 601 (0.2-0.8 mg/kg) 1 h (early treatment) or 4 day post-injury (late treatment) and then injected once daily for consecutive 2 days. Acute neurological and motor deficits were assessed in all rats the day before and 4 days after early MLC 601 treatment. An immunofluorescence microscopy method was used to count the numbers of the cells colocalized with neuron- and apoptosis-specific markers, and the cells colocalized with microglia- and TNF-?-specific markers, in the contused brain regions 4 days post-injury. An immunohistochemistry method was used to evaluate both the number and the morphological transformation of microglia in the injured areas. It was found that early treatment with MLC 601 had better effects in reducing TBI-induced cerebral contusion than did the late therapy with MLC 601. Cerebral contusion caused by TBI was associated with neurological motor deficits, brain apoptosis, and activated microglia (e.g., microgliosis, amoeboid microglia, and microglial overexpression of TNF-?), which all were significantly attenuated by MLC 601 therapy. Our data suggest that MLC 601 is a promising agent for treatment of TBI in rats.
Related JoVE Video
Should EGFR mutations be tested in advanced lung squamous cell carcinomas to guide frontline treatment?
Cancer Chemother. Pharmacol.
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
There is no argument over using epidermal growth factor receptor (EGFR) mutation status to guide the frontline treatment for advanced lung adenocarcinoma (LADC); however, the role of the testing in lung squamous cell carcinoma (LSQC) remains controversial. Currently, the guidelines/consensus statements regarding EGFR mutation testing in LSQC are not consistent among different oncology societies. American Society of Clinical Oncology recommends performing EGFR mutation testing in all patients; European Society for Medical Oncology, College of American Pathologists/International Association for the Study of Lung Cancer/Association for Molecular Pathology, and National Comprehensive Cancer Network suggest for some selected group. EGFR mutation is rarely found in LSQC; however, more importantly, it is not a valid predictive biomarker for EGFR tyrosine kinase inhibitors (EGFR-TKI) in LSQC as it has been shown in LADC. Available data showed that the response rate and progression-free survival in EGFR mutant LSQC patients treated with EGFR-TKI are not better than that observed in patients treated with platinum-doublet chemotherapy in the first-line setting. Therefore, in contrast to advanced LADC, EGFR mutation testing may not be necessarily performed upfront in advanced LSQC because not only the mutation rate is low, but also the predictive value is insufficient. For LSQC patients with known sensitizing-EGFR mutations, both conventional chemotherapy and EGFR-TKI are acceptable frontline treatment options.
Related JoVE Video
Hospitalization for Inflammatory Bowel Disease is Associated with Increased Risk of Breast Cancer: A Nationwide Cohort Study of an Asian Population.
Ann. Surg. Oncol.
PUBLISHED: 05-12-2014
Show Abstract
Hide Abstract
To learn whether women with inflammatory bowel disease (IBD) exhibit a higher risk of breast cancer.
Related JoVE Video
Serum 25-Hydroxyvitamin D Levels in Relation to Lung Function and Exhaled Nitric Oxide in Children.
J. Pediatr.
PUBLISHED: 05-09-2014
Show Abstract
Hide Abstract
To investigate the relationship of vitamin D status with lung function and fraction of exhaled nitric oxide (FeNO) in a population sample of children.
Related JoVE Video
Methylation-associated gene silencing of RARB in areca carcinogens induced mouse oral squamous cell carcinoma.
Biomed Res Int
PUBLISHED: 05-07-2014
Show Abstract
Hide Abstract
Regarding oral squamous cell carcinoma (OSCC) development, chewing areca is known to be a strong risk factor in many Asian cultures. Therefore, we established an OSCC induced mouse model by 4-nitroquinoline-1-oxide (4-NQO), or arecoline, or both treatments, respectively. These are the main two components of the areca nut that could increase the occurrence of OSCC. We examined the effects with the noncommercial MCGI (mouse CpG islands) microarray for genome-wide screening the DNA methylation aberrant in induced OSCC mice. The microarray results showed 34 hypermethylated genes in 4-NQO plus arecoline induced OSCC mice tongue tissues. The examinations also used methylation-specific polymerase chain reaction (MS-PCR) and bisulfite sequencing to realize the methylation pattern in collected mouse tongue tissues and human OSCC cell lines of different grades, respectively. These results showed that retinoic acid receptor ? (RARB) was indicated in hypermethylation at the promoter region and the loss of expression during cancer development. According to the results of real-time PCR, it was shown that de novo DNA methyltransferases were involved in gene epigenetic alternations of OSCC. Collectively, our results showed that RARB hypermethylation was involved in the areca-associated oral carcinogenesis.
Related JoVE Video
Exclusive breastfeeding is associated with reduced cow's milk sensitization in early childhood.
Pediatr Allergy Immunol
PUBLISHED: 04-22-2014
Show Abstract
Hide Abstract
Although breastfed infants have consistently been reported as having fewer infections and respiratory morbidity during infancy, none have reached a definitive conclusion as to whether breastfeeding is an effective strategy to prevent allergic diseases. This study aims to investigate the relationship between exclusive breastfeeding and sequential changes of several biomarkers of allergy, such as absolute eosinophil count, total IgE level, and specific IgE level during the first 3 yrs of life.
Related JoVE Video
Arecoline induces TNF-alpha production and Zonula Occludens-1 redistribution in mouse Sertoli TM4 cells.
J. Biomed. Sci.
PUBLISHED: 04-17-2014
Show Abstract
Hide Abstract
Arecoline, a major alkaloid in Areca nut has the ability to induce oxidative stress. The effect of Areca nut, arecoline on reducing sperm quality and quantity were documented previously using several animal models. Junction disruption by down-regulation of the junction-adhesive protein via oxidative stress is an important route mediating abnormal spermatogenesis. Therefore, in this present study, we investigated the functional role of arecoline on junctional proteins.
Related JoVE Video
A novel approach to propagate flavivirus infectious cDNA clones in bacteria by introducing tandem repeat sequences upstream of virus genome.
J. Gen. Virol.
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
Despite tremendous efforts to improve the methodology for constructing flavivirus infectious cDNAs, the manipulation of flavivirus cDNAs remains a difficult task in bacteria. Here, we successfully propagated DNA-launched type 2 dengue virus (DENV2) and Japanese encephalitis virus (JEV) infectious cDNAs by introducing seven repeats of the tetracycline-response element (7×TRE) and a minimal cytomegalovirus (CMVmin) promoter upstream of the viral genome. Insertion of the 7×TRE-CMVmin sequence upstream of the DENV2 or JEV genome decreased the cryptic E. coli promoter (ECP) activity of the viral genome in bacteria, as measured using fusion constructs containing DENV2 or JEV segments and the reporter gene Renilla luciferase in an empty vector. The growth kinetics of recombinant viruses derived from DNA-launched DENV2 and JEV infectious cDNAs were similar to those of parental viruses. Similarly, RNA-launched DENV2 infectious cDNAs were generated by inserting 7×TRE-CMVmin, five repeats of the GAL4 upstream activating sequence, or five repeats of BamHI linkers upstream of the DENV2 genome. All three tandem repeat sequences decreased the ECP activity of the DENV2 genome in bacteria. Notably, 7×TRE-CMVmin stabilized RNA-launched JEV infectious cDNAs and reduced the ECP activity of the JEV genome in bacteria. The growth kinetics of recombinant viruses derived from RNA-launched DENV2 and JEV infectious cDNAs displayed patterns similar to those of the parental viruses. These results support a novel methodology for constructing flavivirus infectious cDNAs, which will facilitate research in virology, viral pathogenesis and vaccine development of flaviviruses and other RNA viruses.
Related JoVE Video
Factors associated with proceeding to surgical intervention and recurrence of primary spontaneous pneumothorax in adolescent patients.
Eur. J. Pediatr.
PUBLISHED: 04-08-2014
Show Abstract
Hide Abstract
Primary spontaneous pneumothorax (PSP) is not uncommon, and its recurrence is often a challenging clinical problem. Surgical management and predisposing factors for the recurrence of PSP, however, have not yet been well elucidated in adolescent patients. The major aim of this study was to investigate factors associated with proceeding to surgical intervention and recurrence of PSP in adolescents. Two hundred and nineteen episodes of PSP in 171 adolescent patients were retrospectively reviewed. The clinical and radiological spectrum of PSP and factors for proceeding to surgical intervention were assessed in these 171 patients. Risk factors for the recurrence of PSP were further analyzed in 128 patients with first attack of PSP. The male-to-female ratio of the 171 PSP patients was 9:1, and the mean age was 17.6?±?1.5 years. The median body mass index (BMI) percentile was 11 (range 2-31), and 45 (34 %) patients had underweight BMI. The incidence of recurrent PSP was high with a total recurrence rate of 21 %. Ipsilateral recurrence rate of PSP after video-assisted thoracoscopic surgery (VATS) was much less than that of the conservative treatment (4 vs. 18 %). A large-size pneumothorax with a persistent air leak was the most significant factor for proceeding to VATS surgery (P?=?0.001). In addition, it was a significant factor influencing the recurrence of PSP (P?=?0.014). Other factors that did not significantly affect the recurrence rate were BMI, smoking status, and the number of bullae.
Related JoVE Video
Changes in symptom severity in Taiwanese lung cancer patients after gefitinib treatment: a pilot study.
Int J Palliat Nurs
PUBLISHED: 03-29-2014
Show Abstract
Hide Abstract
The purpose of this study was to investigate symptom severity in advanced non-small cell lung cancer patients prior to gefitinib treatment and at 1-, 3- and 6-month intervals after starting treatment.
Related JoVE Video
How a low-fidelity DNA polymerase chooses non-Watson-Crick from Watson-Crick incorporation.
J. Am. Chem. Soc.
PUBLISHED: 03-21-2014
Show Abstract
Hide Abstract
A dogma for DNA polymerase catalysis is that the enzyme binds DNA first, followed by MgdNTP. This mechanism contributes to the selection of correct dNTP by Watson-Crick base pairing, but it cannot explain how low-fidelity DNA polymerases overcome Watson-Crick base pairing to catalyze non-Watson-Crick dNTP incorporation. DNA polymerase X from the deadly African swine fever virus (Pol X) is a half-sized repair polymerase that catalyzes efficient dG:dGTP incorporation in addition to correct repair. Here we report the use of solution structures of Pol X in the free, binary (Pol X:MgdGTP), and ternary (Pol X:DNA:MgdGTP with dG:dGTP non-Watson-Crick pairing) forms, along with functional analyses, to show that Pol X uses multiple unprecedented strategies to achieve the mutagenic dG:dGTP incorporation. Unlike high fidelity polymerases, Pol X can prebind purine MgdNTP tightly and undergo a specific conformational change in the absence of DNA. The prebound MgdGTP assumes an unusual syn conformation stabilized by partial ring stacking with His115. Upon binding of a gapped DNA, also with a unique mechanism involving primarily helix ?E, the prebound syn-dGTP forms a Hoogsteen base pair with the template anti-dG. Interestingly, while Pol X prebinds MgdCTP weakly, the correct dG:dCTP ternary complex is readily formed in the presence of DNA. H115A mutation disrupted MgdGTP binding and dG:dGTP ternary complex formation but not dG:dCTP ternary complex formation. The results demonstrate the first solution structural view of DNA polymerase catalysis, a unique DNA binding mode, and a novel mechanism for non-Watson-Crick incorporation by a low-fidelity DNA polymerase.
Related JoVE Video
Long-term risk of acute coronary syndrome in patients with cholangitis: a 13-year nationwide cohort study.
Eur. J. Intern. Med.
PUBLISHED: 03-19-2014
Show Abstract
Hide Abstract
Patients with cholangitis may exhibit repeated and chronic inflammation of the biliary tract despite successful medical or surgical treatments. This nationwide cohort study examined the association between cholangitis and the subsequent development of acute coronary syndrome (ACS).
Related JoVE Video
Circulating free mitochondrial DNA concentration and its association with erlotinib treatment in patients with adenocarcinoma of the lung.
Oncol Lett
PUBLISHED: 03-14-2014
Show Abstract
Hide Abstract
Changes in circulating free DNA concentrations have been correlated with chemotherapeutic effects in solid tumors. The present study was designed to determine and compare the changes in circulating free mitochondrial DNA (mtDNA) concentrations prior to and following erlotinib treatment, as well as the potential prognostic value of plasma mtDNA. Patients with adenocarcinoma of the lung who were to receive erlotinib treatment were enrolled in the present study once informed consent had been obtained. Patient plasma samples were collected immediately prior to starting erlotinib treatment, on days 15 and 29 following the initiation of erlotinib treatment and also when the patient's disease had progressed. The most common erlotinib treatment response was a partial response (PR), achieved in 26 (49.1%) of the 53 enrolled patients, followed by stable disease (SD) in 13 patients (24.5%) and progressive disease (PD) in 14 patients (26.4%). Plasma mtDNA concentrations were significantly decreased on day 15 compared with day 0 in the patients with PD (P=0.028) or in those patients without a response to erlotinib treatment (SD and PD; P=0.007). Plasma mtDNA concentrations were similar or elevated on day 15 compared with day 0 in the patients with a PR (P=0.808). The concentration of plasma mtDNA did not correlate with progression-free survival (PFS). Tumor epidermal growth factor receptor (EGFR) mutation status (activating mutations in 16 patients and wild-type in 14 patients) did not correlate with the concentration of plasma mtDNA (P=0.951). Plasma mtDNA levels did not correlate with the PFS of the patients when they received erlotinib treatment. The plasma mtDNA levels were decreased on day 15 in those patients who had disease progression following erlotinib treatment. These results demonstrate that plasma mtDNA is of weak clinical utility as a screening, diagnostic or prognostic tool in lung cancer patients.
Related JoVE Video
PP2A and Aurora differentially modify Cdc13 to promote telomerase release from telomeres at G2/M phase.
Nat Commun
PUBLISHED: 03-07-2014
Show Abstract
Hide Abstract
In yeast, the initiation of telomere replication at the late S phase involves in combined actions of kinases on Cdc13, the telomere binding protein. Cdc13 recruits telomerase to telomeres through its interaction with Est1, a component of telomerase. However, how cells terminate the function of telomerase at G2/M is still elusive. Here we show that the protein phosphatase 2A (PP2A) subunit Pph22 and the yeast Aurora kinase homologue Ipl1 coordinately inhibit telomerase at G2/M by dephosphorylating and phosphorylating the telomerase recruitment domain of Cdc13, respectively. While Pph22 removes Tel1/Mec1-mediated Cdc13 phosphorylation to reduce Cdc13-Est1 interaction, Ipl1-dependent Cdc13 phosphorylation elicits dissociation of Est1-TLC1, the template RNA component of telomerase. Failure of these regulations prevents telomerase from departing telomeres, causing perturbed telomere lengthening and prolonged M phase. Together our results demonstrate that differential and additive actions of PP2A and Aurora on Cdc13 limit telomerase action by removing active telomerase from telomeres at G2/M phase.
Related JoVE Video
First-line pemetrexed plus cisplatin followed by gefitinib maintenance therapy versus gefitinib monotherapy in East Asian patients with locally advanced or metastatic non-squamous non-small cell lung cancer: a randomised, phase 3 trial.
Eur. J. Cancer
PUBLISHED: 03-06-2014
Show Abstract
Hide Abstract
In the Iressa Pan-ASia Study (IPASS), gefitinib claimed improved progression-free survival (PFS) versus carboplatin-paclitaxel in clinically selected lung cancer patients. The primary objective of this study was to assess the PFS of pemetrexed-cisplatin (PC) followed by gefitinib maintenance versus gefitinib monotherapy in an IPASS-like population.
Related JoVE Video
Fha interaction with phosphothreonine of TssL activates type VI secretion in Agrobacterium tumefaciens.
PLoS Pathog.
PUBLISHED: 03-01-2014
Show Abstract
Hide Abstract
The type VI secretion system (T6SS) is a widespread protein secretion system found in many Gram-negative bacteria. T6SSs are highly regulated by various regulatory systems at multiple levels, including post-translational regulation via threonine (Thr) phosphorylation. The Ser/Thr protein kinase PpkA is responsible for this Thr phosphorylation regulation, and the forkhead-associated (FHA) domain-containing Fha-family protein is the sole T6SS phosphorylation substrate identified to date. Here we discovered that TssL, the T6SS inner-membrane core component, is phosphorylated and the phosphorylated TssL (p-TssL) activates type VI subassembly and secretion in a plant pathogenic bacterium, Agrobacterium tumefaciens. Combining genetic and biochemical approaches, we demonstrate that TssL is phosphorylated at Thr 14 in a PpkA-dependent manner. Further analysis revealed that the PpkA kinase activity is responsible for the Thr 14 phosphorylation, which is critical for the secretion of the T6SS hallmark protein Hcp and the putative toxin effector Atu4347. TssL phosphorylation is not required for the formation of the TssM-TssL inner-membrane complex but is critical for TssM conformational change and binding to Hcp and Atu4347. Importantly, Fha specifically interacts with phosphothreonine of TssL via its pThr-binding motif in vivo and in vitro and this interaction is crucial for TssL interaction with Hcp and Atu4347 and activation of type VI secretion. In contrast, pThr-binding ability of Fha is dispensable for TssM structural transition. In conclusion, we discover a novel Thr phosphorylation event, in which PpkA phosphorylates TssL to activate type VI secretion via its direct binding to Fha in A. tumefaciens. A model depicting an ordered TssL phosphorylation-induced T6SS assembly pathway is proposed.
Related JoVE Video
Differential diagnosis of nonmelanoma pigmented skin lesions based on harmonic generation microscopy.
J Biomed Opt
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
In vivo harmonic generation microscopy (HGM) has been applied successfully in healthy human skin and can achieve a submicron resolution, similar to histopathologic examination, even at a penetration depth up to 270 ?m. This study aims to investigate the clinical applicability of HGM imaging for differential diagnosis of nonmelanoma pigmented skin lesions. A total of 42 pigmented skin tumors, including pigmented basal cell carcinoma, melanocytic nevus, and seborrheic keratosis were evaluated by HGM ex vivo or in vivo. Based on the standard histopathologic characteristics, we established the corresponding HGM imaging criteria for each pigmented tumor. Diagnostic performance of HGM for differentiating nonmelanoma pigmented skin tumors was evaluated through the observers' direct general assessment (overall evaluation) or the presence of two imaging criteria with the highest sensitivity and specificity (major criteria evaluation). Our results show that, based on the direct general assessment, the sensitivity is 92% [95% confidence interval (CI): 67 to 97%] and the specificity is 96% (95% CI: 83 to 99%); by major criteria evaluation, 94% sensitivity (95% CI: 70 to 99%) and 100% specificity (95% CI: 87 to 100%) are achieved. Our study indicates that HGM serves as a promising histopathological examination tool for noninvasive differential diagnostics of nonmelanoma pigmented skin tumors.
Related JoVE Video
Biosynthesis of streptolidine involved two unexpected intermediates produced by a dihydroxylase and a cyclase through unusual mechanisms.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Streptothricin-F (STT-F), one of the early-discovered antibiotics, consists of three components, a ?-lysine homopolymer, an aminosugar D-gulosamine, and an unusual bicyclic streptolidine. The biosynthesis of streptolidine is a long-lasting but unresolved puzzle. Herein, a combination of genetic/biochemical/structural approaches was used to unravel this problem. The STT gene cluster was first sequenced from a Streptomyces variant BCRC 12163, wherein two gene products OrfP and OrfR were characterized in?vitro to be a dihydroxylase and a cyclase, respectively. Thirteen high-resolution crystal structures for both enzymes in different reaction intermediate states were snapshotted to help elucidate their catalytic mechanisms. OrfP catalyzes an Fe(II) -dependent double hydroxylation reaction converting L-Arg into (3R,4R)-(OH)2 -L-Arg via (3S)-OH-L-Arg, while OrfR catalyzes an unusual PLP-dependent elimination/addition reaction cyclizing (3R,4R)-(OH)2 -L-Arg to the six-membered (4R)-OH-capreomycidine. The biosynthetic mystery finally comes to light as the latter product was incorporation into STT-F by a feeding experiment.
Related JoVE Video
Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47(phox) pathway.
Toxicol. Appl. Pharmacol.
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phox activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases.
Related JoVE Video
A prospective, molecular epidemiology study of EGFR mutations in Asian patients with advanced non-small-cell lung cancer of adenocarcinoma histology (PIONEER).
J Thorac Oncol
PUBLISHED: 01-15-2014
Show Abstract
Hide Abstract
PIONEER (NCT01185314) was a prospective, multinational, epidemiological study of epidermal growth factor receptor (EGFR) mutations in patients from Asia with newly diagnosed advanced lung adenocarcinoma.
Related JoVE Video
Diabetes mellitus and increased postoperative risk of acute renal failure after hepatectomy for hepatocellular carcinoma: a nationwide population-based study.
Ann. Surg. Oncol.
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
This study aimed to determine the effects of diabetes mellitus (DM) on the risk of surgical mortality and morbidity in patients undergoing hepatectomy for hepatocellular carcinoma (HCC).
Related JoVE Video
Long-term risk of acute coronary syndrome in patients with inflammatory bowel disease: a 13-year nationwide cohort study in an Asian population.
Inflamm. Bowel Dis.
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
Whether patients with inflammatory bowel disease (IBD) exhibit a higher risk of developing acute coronary syndrome (ACS) remains debatable.
Related JoVE Video
Tight regulation of a timed nuclear import wave of EKLF by PKC? and FOE during Pro-E to Baso-E transition.
Dev. Cell
PUBLISHED: 01-13-2014
Show Abstract
Hide Abstract
Erythropoiesis is a highly regulated process during which BFU-E are differentiated into RBCs through CFU-E, Pro-E, PolyCh-E, OrthoCh-E, and reticulocyte stages. Uniquely, most erythroid-specific genes are activated during the Pro-E to Baso-E transition. We show that a wave of nuclear import of the erythroid-specific transcription factor EKLF occurs during the Pro-E to Baso-E transition. We further demonstrate that this wave results from a series of finely tuned events, including timed activation of PKC?, phosphorylation of EKLF at S68 by P-PKC?(S676), and sumoylation of EKLF at K74. The latter EKLF modifications modulate its interactions with a cytoplasmic ankyrin-repeat-protein FOE and importin?1, respectively. The role of FOE in the control of EKLF nuclear import is further supported by analysis of the subcellular distribution patterns of EKLF in FOE-knockout mice. This study reveals the regulatory mechanisms of the nuclear import of EKLF, which may also be utilized in the nuclear import of other factors.
Related JoVE Video
Risk factors and outcomes for multidrug-resistant Gram-negative bacteremia in the NICU.
Pediatrics
PUBLISHED: 01-13-2014
Show Abstract
Hide Abstract
To assess the risk factors antibiotic therapy and outcomes of multidrug-resistant (MDR) Gram-negative bacilli (GNB) bacteremia in NICU patients.
Related JoVE Video
Structure and mechanism of a nonhaem-iron SAM-dependent C-methyltransferase and its engineering to a hydratase and an O-methyltransferase.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 01-06-2014
Show Abstract
Hide Abstract
In biological systems, methylation is most commonly performed by methyltransferases (MTs) using the electrophilic methyl source S-adenosyl-L-methionine (SAM) via the S(N)2 mechanism. (2S,3S)-?-Methylphenylalanine, a nonproteinogenic amino acid, is a building unit of the glycopeptide antibiotic mannopeptimycin. The gene product of mppJ from the mannopeptimycin-biosynthetic gene cluster is the MT that methylates the benzylic C atom of phenylpyruvate (Ppy) to give ?MePpy. Although the benzylic C atom of Ppy is acidic, how its nucleophilicity is further enhanced to become an acceptor for C-methylation has not conclusively been determined. Here, a structural approach is used to address the mechanism of MppJ and to engineer it for new functions. The purified MppJ displays a turquoise colour, implying the presence of a metal ion. The crystal structures reveal MppJ to be the first ferric ion SAM-dependent MT. An additional four structures of binary and ternary complexes illustrate the molecular mechanism for the metal ion-dependent methyltransfer reaction. Overall, MppJ has a nonhaem iron centre that bind, orients and activates the ?-ketoacid substrate and has developed a sandwiched bi-water device to avoid the formation of the unwanted reactive oxo-iron(IV) species during the C-methylation reaction. This discovery further prompted the conversion of the MT into a structurally/functionally unrelated new enzyme. Through stepwise mutagenesis and manipulation of coordination chemistry, MppJ was engineered to perform both Lewis acid-assisted hydration and/or O-methyltransfer reactions to give stereospecific new compounds. This process was validated by six crystal structures. The results reported in this study will facilitate the development and design of new biocatalysts for difficult-to-synthesize biochemicals.
Related JoVE Video
Involvement of the nuclear high mobility group B1 peptides released from injured hepatocytes in murine hepatic fibrogenesis.
Biochim. Biophys. Acta
PUBLISHED: 01-05-2014
Show Abstract
Hide Abstract
This study investigated the pro-fibrogenic role of high mobility group box 1 (HMGB1) peptides in liver fibrogenesis. An animal model of carbon tetrachloride (CCl4)-induced liver fibrosis was used to examine the serum HMGB1 levels and its intrahepatic distribution. The increased serum HMGB1 levels were positively correlated with elevation of transforming growth factor-?1 (TGF-?1) and collagen deposition during fibrogenesis. The cytoplasmic distribution of HMGB1 was noted in the parenchymal hepatocytes of fibrotic livers. In vitro studies confirmed that exposure to hydrogen peroxide and CCl4 induced an intracellular mobilization and extracellular release of nuclear HMGB1 peptides in clone-9 and primary hepatocytes, respectively. An uptake of exogenous HMGB1 by hepatic stellate cells (HSCs) T6 cells indicated a possible paracrine action of hepatocytes on HSCs. Moreover, HMGB1 dose-dependently stimulated HSC proliferation, up-regulated de novo synthesis of collagen type I and ?-smooth muscle actin (?-SMA), and triggered Smad2 phosphorylation and its nuclear translocation through a TGF-?1-independent mechanism. Blockade with neutralizing antibodies and gene silencing demonstrated the involvement of the receptor for advanced glycation end-products (RAGE), but not toll-like receptor 4, in cellular uptake of HMGB1 and the HMGB1-mediated Smad2 and ERK1/2 phosphorylation as well as ?-SMA up-regulation in HSC-T6 cells. Furthermore, anti-RAGE treatment significantly ameliorated CCl4-induced liver fibrosis. In conclusion, the nuclear HMGB1 peptides released from parenchymal hepatocytes during liver injuries may directly activate HSCs through stimulating HSC proliferation and transformation, eventually leading to the fibrotic changes of livers. Blockade of HMGB1/RAGE signaling cascade may constitute a therapeutic strategy for treatment of liver fibrosis.
Related JoVE Video
Cytokine responses of TNF-?, IL-6, and IL-10 in G6PD-deficient infants.
Pediatr Hematol Oncol
PUBLISHED: 01-02-2014
Show Abstract
Hide Abstract
G6PD-deficient adults are reported to be susceptible to severe infection, and decreased cytokine responses have been postulated as the underlying mechanism. However, investigating the association of G6PD deficiency and cytokine responses during infancy is lacking. The current study aims to determine whether cytokine responses of tumor necrosis factor ()-?, interleukins (IL)-6, and IL-10 are impaired in the G6PD-deficient infants. Upon agreements with informed consents, peripheral blood mononuclear cells (PBMCs) of enrolled infants were collected twice at 1 month and 1 year of age. PBMCs were then stimulated with toll-like receptor (TLR) agonists-including PAM3csk4 for TLR1-2, poly (I:C) for TLR3, and lipopolysaccharide for TLR4-to analyze the expression of TNF-?, IL-6, and IL-10. Males (P = .004) and phototherapy during neonatal period (P = .008) were more common among G6PD-deficient infants than G6PD-normal subjects. After the stimulation of TLR agonists, there was no significant difference in the expression of TNF-?, IL-6, and IL-10 between PBMCs of G6PD-deficient and -normal infants at both 1 month and 1 year of age. In conclusion, the clinical characteristics of G6PD-deficient infants are different from those of G6PD-normal subjects. The data suggest that the innate immune responses to TLR agonists in G6PD-deficient infants are not different from those of G6PD-normal infants.
Related JoVE Video
Up-Regulation of Nerve Growth Factor in Cholestatic Livers and Its Hepatoprotective Role against Oxidative Stress.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The role of nerve growth factor (NGF) in liver injury induced by bile duct ligation (BDL) remains elusive. This study aimed to investigate the relationship between inflammation and hepatic NGF expression, to explore the possible upstream molecules up-regulating NGF, and to determine whether NGF could protect hepatocytes from oxidative liver injury. Biochemical and molecular detection showed that NGF was up-regulated in cholestatic livers and plasma, and well correlated with systemic and hepatic inflammation. Conversely, systemic immunosuppression reduced serum NGF levels and resulted in higher mortality in BDL-treated mice. Immunohistochemistry showed that the up-regulated NGF was mainly localized in parenchymal hepatocytes. In vitro mechanistic study further demonstrated that TGF-?1 up-regulated NGF expression in clone-9 and primary rat hepatocytes. Exogenous NGF supplementation and endogenous NGF overexpression effectively protected hepatocytes against TGF-?1- and oxidative stress-induced cell death in vitro, along with reduced formation of oxidative adducted proteins modified by 4-HNE and 8-OHdG. TUNEL staining confirmed the involvement of anti-apoptosis in the NGF-exhibited hepatoprotection. Moreover, NGF potently induced Akt phosphorylation and increased Bcl-2 to Bax ratios, whereas these molecular alterations by NGF were only seen in the H2O2-, but not TGF-?1-treated hepatocytes. In conclusion, NGF exhibits anti-oxidative and hepatoprotective effects and is suggested to be therapeutically applicable in treating cholestatic liver diseases.
Related JoVE Video
Low-molecular-weight heparin and unfractionated heparin decrease th-1, 2, and 17 expressions.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
We evaluated the effects of T helper cell differentiation in a mite-allergic animal model treated with inhaled heparins of different molecular weight.
Related JoVE Video
Neurological complications after neonatal bacteremia: the clinical characteristics, risk factors, and outcomes.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Neonates with bacteremia are at risk of neurologic complications. Relevant information warrants further elucidation.
Related JoVE Video
Outcomes and characteristics of patients undergoing percutaneous angioplasty followed by below-knee or above-knee amputation for peripheral artery disease.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Little is known about long-term outcomes among patients who receive percutaneous angioplasty (PTA) for peripheral artery disease (PAD) then undergo below-knee or above-knee amputations. We sought to determine clinical outcomes associated with below-knee or above-knee amputation, along with possible explanatory factors and treatment strategies.
Related JoVE Video
Sensitization to food and inhalant allergens in relation to atopic diseases in early childhood: a birth cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
A correct interpretation of sensitization to common allergens is critical in determining susceptibility to allergic diseases. The aim of this study was to investigate the patterns of sensitization to food and inhalant allergens, and their relation to the development of atopic diseases in early childhood.
Related JoVE Video
Suboptimal vitamin D status in a population-based study of Asian children: prevalence and relation to allergic diseases and atopy.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
New evidence shows high prevalence of vitamin D deficiency in many countries and some studies suggest a possible link between vitamin D status and allergic diseases. The objectives of this study were to determine the prevalence of suboptimal vitamin D status in a population sample of Asian children and to investigate the relationship of vitamin D status with allergic diseases and atopy.
Related JoVE Video
Polymicrobial bloodstream infection in neonates: microbiology, clinical characteristics, and risk factors.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Polymicrobial bloodstream infections (PBSIs) have been associated with complex underlying medical conditions and a high incidence of specific microorganisms in several settings, but the relevant data are scarce in neonates.
Related JoVE Video
Modulation of HIV-1-Induced Activation of Plasmacytoid Dendritic Cells by 6-Desfluoroquinolones.
AIDS Res. Hum. Retroviruses
PUBLISHED: 12-09-2013
Show Abstract
Hide Abstract
Abstract Chronic activation of plasmacytoid dendritic cells (pDCs) is an important contributor to the immunopathogenesis of HIV infection. The quinolone derivative chloroquine (CQ) prevents endosomal acidification, required for toll-like receptor sensing of HIV by pDCs, and is currently under clinical trial as an immunotherapeutic approach. We tested three different 6-desfluoroquinolones (6-DFQs), structurally related to CQ and endowed with antiretroviral activity, for their ability to inhibit HIV-induced pDC activation and interferon (IFN)-? production in peripheral blood mononuclear cells (PBMCs) in vitro. PBMCs from six healthy donors were cultured overnight with aldrithiol-2 (AT-2)-inactivated HIV-1MN in the presence or absence of 6-DFQs or CQ. IFN-? production was measured by ELISA; pDC and monocyte activation was analyzed by flow cytometry. Incubation with HIV labeled with the fluorescent dye DyLight-488 (DL488) was used to test virus uptake by flow cytometry. We found that the 6-DFQs effectively inhibited HIV-induced IFN-? similar to CQ, but only 6-DFQs also inhibited the upregulation of the pDC activation marker CD83. Interestingly, HIV-induced expression of the costimulatory molecule CD80 and, to a lesser extent CD86, was further enhanced on pDCs by 6-DFQs, but not CQ. Conversely, 6-DFQs and CQ had similar inhibitory effects on HIV-induced monocyte activation, consistent with the primary mechanism being associated with IFN-? signaling. Finally, 6-DFQs interfered with HIV interaction with pDCs and monocytes, but not myeloid DCs. Our data indicate that 6-DFQs may interfere with pDC-mediated and IFN-?-dependent immunopathogenesis while supporting pDC differentiation into mature antigen-presenting cells by favoring expression of costimulatory molecules.
Related JoVE Video
Use of quantitative mass spectrometric analysis to elucidate the mechanisms of phospho-priming and auto-activation of the checkpoint kinase Rad53 in vivo.
Mol. Cell Proteomics
PUBLISHED: 12-03-2013
Show Abstract
Hide Abstract
The cell cycle checkpoint kinases play central roles in genome maintenance of eukaryotes. Activation of the yeast checkpoint kinase Rad53 involves Rad9 or Mrc1 adaptor-mediated phospho-priming by Mec1 kinase, followed by auto-activating phosphorylation within its activation loop. However, mechanisms of how these adaptors regulate priming phosphorylation of specific sites and how this then leads to Rad53 activation remain poorly understood. Here we use quantitative mass spectrometry to delineate the stepwise phosphorylation events in the activation of endogenous Rad53 in response to S phase alkylation DNA damage, and show that the two Rad9 and Mrc1 adaptors, the four N-terminal Mec1-target TQ sites of Rad53 (Rad53-SCD1), and the Rad53-FHA2 coordinate intimately for optimal priming phosphorylation to support substantial Rad53 auto-activation. Rad9 or Mrc1 alone can mediate surprisingly similar Mec1-target site phosphorylation patterns of Rad53, including previously undetected tri- and tetra-phosphorylation of Rad53-SCD1. Reducing the number of TQ motifs turns the SCD1 into a proportionally poorer Mec1 target, which then requires the presence of both Mrc1 and Rad9 for sufficient priming and auto-activation. The phosphothreonine-interacting Rad53-FHA domains, particularly FHA2, regulate phospho-priming by interacting with the checkpoint mediators, but do not seem to play a major role in the phospho-SCD1-dependent auto-activation step. Finally, mutation of all four SCD1 TQ motifs greatly reduces Rad53 activation, but does not eliminate it, and residual Rad53 activity in this mutant is dependent on Rad9 but not Mrc1. Altogether, our results provide a paradigm for how phosphorylation site clusters and checkpoint mediators can be involved in the regulation of signaling relay in kinase-kinase cascades in vivo, and elucidate an SCD1-independent Rad53 auto-activation mechanism through the Rad9 pathway. The work also demonstrates the power of mass spectrometry for in-depth analyses of molecular mechanisms in cellular signaling in vivo.
Related JoVE Video
Long-term effects of stimulants on neurocognitive performance of Taiwanese children with attention-deficit/hyperactivity disorder.
BMC Psychiatry
PUBLISHED: 11-26-2013
Show Abstract
Hide Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a common behavioral and neurocognitive disorder in school-age children. Methylphenidate (MPH) is the most frequently prescribed CNS stimulant for ADHD. The aim of this study is to evaluate the changes in intelligence quotient and domains of neurocognitive function after long-term MPH treatment of Taiwanese children with ADHD.
Related JoVE Video
The E3 ubiquitin ligase SIAH2 is a prosurvival factor overexpressed in oral cancer.
Anticancer Res.
PUBLISHED: 11-14-2013
Show Abstract
Hide Abstract
This study aimed at investigating the expression and functional significance of seven in absentia homologues 2 (SIAH2), an E3 ubiquitin ligase, in oral squamous cell carcinoma (OSCC).
Related JoVE Video
Interaction between Salt-inducible Kinase 2 (SIK2) and p97/Valosin-containing Protein (VCP) Regulates Endoplasmic Reticulum (ER)-associated Protein Degradation in Mammalian Cells.
J. Biol. Chem.
PUBLISHED: 10-15-2013
Show Abstract
Hide Abstract
Salt-inducible kinase 2 (SIK2) is an important regulator of cAMP response element-binding protein-mediated gene expression in various cell types and is the only AMP-activated protein kinase family member known to interact with the p97/valosin-containing protein (VCP) ATPase. Previously, we have demonstrated that SIK2 can regulate autophagy when proteasomal function is compromised. Here we report that physical and functional interactions between SIK2 and p97/VCP underlie the regulation of endoplasmic reticulum (ER)-associated protein degradation (ERAD). SIK2 co-localizes with p97/VCP in the ER membrane and stimulates its ATPase activity through direct phosphorylation. Although the expression of wild-type recombinant SIK2 accelerated the degradation and removal of ERAD substrates, the kinase-deficient variant conversely had no effect. Furthermore, down-regulation of endogenous SIK2 or mutation of the SIK2 target site on p97/VCP led to impaired degradation of ERAD substrates and disruption of ER homeostasis. Collectively, these findings highlight a mechanism by which the interplay between SIK2 and p97/VCP contributes to the regulation of ERAD in mammalian cells.
Related JoVE Video
Development of 3D carbon nanotube interdigitated finger electrodes on polymer substrate for flexible capacitive sensor application.
Nanotechnology
PUBLISHED: 10-10-2013
Show Abstract
Hide Abstract
This study reports a novel approach to the implementation of 3D carbon nanotube (CNT) interdigitated finger electrodes on flexible polymer, and the detection of strain, bending curvature, tactile force and proximity distance are demonstrated. The merits of the presented CNT-based flexible sensor are as follows: (1) the silicon substrate is patterned to enable the formation of 3D vertically aligned CNTs on the substrate surface; (2) polymer molding on the silicon substrate with 3D CNTs is further employed to transfer the 3D CNTs to the flexible polymer substrate; (3) the CNT-polymer composite (~70 ?m in height) is employed to form interdigitated finger electrodes to increase the sensing area and initial capacitance; (4) other structures such as electrical routings, resistors and mechanical supporters are also available using the CNT-polymer composite. The preliminary fabrication results demonstrate a flexible capacitive sensor with 50 ?m high CNT interdigitated electrodes on a poly-dimethylsiloxane substrate. The tests show that the typical capacitance change is several dozens of fF and the gauge factor is in the range of 3.44-4.88 for strain and bending curvature measurement; the sensitivity of the tactile sensor is 1.11% N(-1); a proximity distance near 2 mm away from the sensor can be detected.
Related JoVE Video
Second-line pemetrexed treatment in Taiwanese patients with advanced nonsmall cell lung cancer: an open-label single-arm study.
J. Formos. Med. Assoc.
PUBLISHED: 09-21-2013
Show Abstract
Hide Abstract
Although global and Asian studies on second-line pemetrexed for the treatment of advanced nonsmall cell lung cancer have confirmed its efficacy and safety, a pivotal postcommitment study to consolidate the evidence regarding the Taiwanese population was warranted. This open-label single-arm study assessed the objective response rate to a tailored dose of single-agent pemetrexed in Taiwanese patients with advanced nonsmall cell lung cancer who had received prior chemotherapy.
Related JoVE Video
Eupafolin, a skin whitening flavonoid isolated from Phyla nodiflora, downregulated melanogenesis: Role of MAPK and Akt pathways.
J Ethnopharmacol
PUBLISHED: 09-04-2013
Show Abstract
Hide Abstract
In hyperpigmentation disorders marked by melanin overproduction in the skin, including melisma and freckles, melanogenesis is caused by tyrosinase overexpression. Natural medicinal resources, like Phyla nodiflora, a traditional Chinese herbal medicine, have been used for a long time to management of dermatological conditions, such as skin inflammation and melanogenesis. Eupafolin, a functional flavonoid isolated from Phyla nodiflora, is an herbal tea constituent and possesses anti-inflammatory and anticancer activities. However, molecular mechanisms of eupafolin-mediated antimelanogenesis remain unknown. We thus focused on its antimelanogenesis effects in B16F10 mouse melanoma cells.
Related JoVE Video
Spontaneous lytic replication and epitheliotropism define an Epstein-Barr virus strain found in carcinomas.
Cell Rep
PUBLISHED: 08-12-2013
Show Abstract
Hide Abstract
The Epstein-Barr virus (EBV) is found in a variety of tumors whose incidence greatly varies around the world. A poorly explored hypothesis is that particular EBV strains account for this phenomenon. We report that M81, a virus isolated from a Chinese patient with nasopharyngeal carcinoma (NPC), shows remarkable similarity to other NPC viruses but is divergent from all other known strains. M81 exhibited a reversed tropism relative to common strains with a reduced ability to infect B cells and a high propensity to infect epithelial cells, which is in agreement with its isolation from carcinomas. M81 spontaneously replicated in B cells in vitro and in vivo at unusually high levels, in line with the enhanced viral replication observed in NPC patients. Spontaneous replication and epitheliotropism could be partly ascribed to polymorphisms within viral proteins. We suggest considering M81 and its closely related isolates as an EBV subtype with enhanced pathogenic potential.
Related JoVE Video
A web-based audiometry database system.
J. Formos. Med. Assoc.
PUBLISHED: 07-23-2013
Show Abstract
Hide Abstract
To establish a real-time, web-based, customized audiometry database system, we worked in cooperation with the departments of medical records, information technology, and otorhinolaryngology at our hospital. This system includes an audiometry data entry system, retrieval and display system, patient information incorporation system, audiometry data transmission program, and audiometry data integration. Compared with commercial audiometry systems and traditional hand-drawn audiometry data, this web-based system saves time and money and is convenient for statistics research.
Related JoVE Video
Automatic cell segmentation and nuclear-to-cytoplasmic ratio analysis for third harmonic generated microscopy medical images.
IEEE Trans Biomed Circuits Syst
PUBLISHED: 07-16-2013
Show Abstract
Hide Abstract
Traditional biopsy procedures require invasive tissue removal from a living subject, followed by time-consuming and complicated processes, so noninvasive in vivo virtual biopsy, which possesses the ability to obtain exhaustive tissue images without removing tissues, is highly desired. Some sets of in vivo virtual biopsy images provided by healthy volunteers were processed by the proposed cell segmentation approach, which is based on the watershed-based approach and the concept of convergence index filter for automatic cell segmentation. Experimental results suggest that the proposed algorithm not only reveals high accuracy for cell segmentation but also has dramatic potential for noninvasive analysis of cell nuclear-to-cytoplasmic ratio (NC ratio), which is important in identifying or detecting early symptoms of diseases with abnormal NC ratios, such as skin cancers during clinical diagnosis via medical imaging analysis.
Related JoVE Video
Phase III study of afatinib or cisplatin plus pemetrexed in patients with metastatic lung adenocarcinoma with EGFR mutations.
J. Clin. Oncol.
PUBLISHED: 07-01-2013
Show Abstract
Hide Abstract
The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS).
Related JoVE Video
Separating spectral mixtures in hyperspectral image data using independent component analysis: validation with oral cancer tissue sections.
J Biomed Opt
PUBLISHED: 06-26-2013
Show Abstract
Hide Abstract
ABSTRACT. Recently, hyperspectral imaging (HSI) systems, which can provide 100 or more wavelengths of emission autofluorescence measures, have been used to delineate more complete spectral patterns associated with certain molecules relevant to cancerization. Such a spectral fingerprint may reliably correspond to a certain type of molecule and thus can be treated as a biomarker for the presence of that molecule. However, the outcomes of HSI systems can be a complex mixture of characteristic spectra of a variety of molecules as well as optical interferences due to reflection, scattering, and refraction. As a result, the mixed nature of raw HSI data might obscure the extraction of consistent spectral fingerprints. Here we present the extraction of the characteristic spectra associated with keratinized tissues from the HSI data of tissue sections from 30 oral cancer patients (31 tissue samples in total), excited at two different wavelength ranges (330 to 385 and 470 to 490 nm), using independent and principal component analysis (ICA and PCA) methods. The results showed that for both excitation wavelength ranges, ICA was able to resolve much more reliable spectral fingerprints associated with the keratinized tissues for all the oral cancer tissue sections with significantly higher mean correlation coefficients as compared to PCA (p<0.001).
Related JoVE Video
Molecular basis of the essential s phase function of the rad53 checkpoint kinase.
Mol. Cell. Biol.
PUBLISHED: 06-10-2013
Show Abstract
Hide Abstract
The essential yeast kinases Mec1 and Rad53, or human ATR and Chk1, are crucial for checkpoint responses to exogenous genotoxic agents, but why they are also required for DNA replication in unperturbed cells remains poorly understood. Here we report that even in the absence of DNA-damaging agents, the rad53-4AQ mutant, lacking the N-terminal Mec1 phosphorylation site cluster, is synthetic lethal with a deletion of the RAD9 DNA damage checkpoint adaptor. This phenotype is caused by an inability of rad53-4AQ to activate the downstream kinase Dun1, which then leads to reduced basal deoxynucleoside triphosphate (dNTP) levels, spontaneous replication fork stalling, and constitutive activation of and dependence on S phase DNA damage checkpoints. Surprisingly, the kinase-deficient rad53-K227A mutant does not share these phenotypes but is rendered inviable by additional phosphosite mutations that prevent its binding to Dun1. The results demonstrate that ultralow Rad53 catalytic activity is sufficient for normal replication of undamaged chromosomes as long as it is targeted toward activation of the effector kinase Dun1. Our findings indicate that the essential S phase function of Rad53 is comprised by the combination of its role in regulating basal dNTP levels and its compensatory kinase function if dNTP levels are perturbed.
Related JoVE Video
Histone demethylase RBP2 promotes lung tumorigenesis and cancer metastasis.
Cancer Res.
PUBLISHED: 05-30-2013
Show Abstract
Hide Abstract
The retinoblastoma binding protein RBP2 (KDM5A) is a histone demethylase that promotes gastric cancer cell growth and is enriched in drug-resistant lung cancer cells. In tumor-prone mice lacking the tumor suppressor gene RB or MEN1, genetic ablation of RBP2 can suppress tumor initiation, but the pathogenic breadth and mechanistic aspects of this effect relative to human tumors have not been defined. Here, we approached this question in the context of lung cancer. RBP2 was overexpressed in human lung cancer tissues where its depletion impaired cell proliferation, motility, migration, invasion, and metastasis. RBP2 oncogenicity relied on its demethylase and DNA-binding activities. RBP2 upregulated expression of cyclins D1 and E1 while suppressing the expression of cyclin-dependent kinase inhibitor p27 (CDKN1B), each contributing to RBP2-mediated cell proliferation. Expression microarray analyses revealed that RBP2 promoted expression of integrin-?1 (ITGB1), which is implicated in lung cancer metastasis. Mechanistic investigations established that RBP2 bound directly to the p27, cyclin D1, and ITGB1 promoters and that exogenous expression of cyclin D1, cyclin E1, or ITGB1 was sufficient to rescue proliferation or migration/invasion, respectively. Taken together, our results establish an oncogenic role for RBP2 in lung tumorigenesis and progression and uncover novel RBP2 targets mediating this role.
Related JoVE Video
Evidence that P12, a specific variant of P16(INK4A), plays a suppressive role in human pancreatic carcinogenesis.
Biochem. Biophys. Res. Commun.
PUBLISHED: 05-03-2013
Show Abstract
Hide Abstract
The INK4a-ARF locus plays a central role in the development of pancreatic tumors as evidenced by the fact that up to 98% of pancreatic tumor specimens harbored genetic alterations at the INK4a-ARF locus. Interestingly, in addition to the well-known P16(INK4A) (P16) and P14ARF tumor suppressors, the INK4a-ARF locus in pancreas encodes another protein, P12, whose structure, function, and contributions to pancreatic carcinogenesis remain to be elucidated. In the current study, we demonstrated that over-expression of p12 in human pancreatic cancer cells led to cell arrest at the G1 phase and such cell cycle arrest was related to down-regulation of a number of oncogenes, such as c-Jun, Fos, and SEI1. Furthermore, unlike P16, P12 did not retain any cyclin-dependent kinase 4 (CDK4)-inhibitory activity. Instead, P12 exhibited a transactivating activity not found in P16. We also examined the genetic status of p12 in a cohort of 40 pancreatic tumor specimens and found that p12 alteration was prevalent in pancreatic tumors with an incidence of 70% (28/40). These results support that P12 is a tumor suppressive protein distinct from P16, and its genetic inactivation is associated with pancreatic carcinogenesis.
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.