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Find video protocols related to scientific articles indexed in Pubmed.
Identification and characterisation of novel inhibitors on extrinsic tenase complex from Bungarus fasciatus (banded krait) venom.
Thromb. Haemost.
PUBLISHED: 12-31-2014
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Snake venoms are excellent sources of pharmacologically active proteins and peptides, and hence are potential sources of leads for drug developments. It has been previously established that krait (Bungarus genus) venoms contain mainly neurotoxins. A screening for anticoagulants showed that Bungarus fasciatus venom exhibits potent anticoagulant effect in standard clotting assays. Through sequential fractionation of the venom by size exclusion and high performance liquid chromatographies, coupled with functional screening for anticoagulant activities, we have isolated and purified two anticoagulant proteins, termed BF-AC1 (Bungarus fasciatusanticoagulant 1) and BF-AC2. They have potent inhibitory activities (IC50 of 10 nM) on the extrinsic tenase complex. Structurally, these proteins each has two subunits covalently held together by disulfide bond(s). The N-terminal sequences of the individual subunits of BF-AC1 and BF-AC2 showed that the larger subunit is homologous to phospholipase A2, while the smaller subunit is homologous to Kunitz type serine proteinase inhibitor. Functionally, in addition to their anticoagulant activity, these proteins showed presynaptic neurotoxic effects in both in vivo and ex vivo experiments. Thus, BF-AC1 and BF-AC2 are structurally and functionally similar to ?-bungarotoxins, a class of neurotoxins. The enzymatic activity of phospholipase A2 subunit plays a significant role in the anticoagulant activities. This is the first report on the anticoagulant activity of?-bungarotoxins and these results expand on the existing catalogue of haemostatically active snake venom proteins.
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Colorectal cancer incidence and mortality in china, 2010.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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The National Central Cancer Registry of China (NCCR) affiliated to the Bureau of Disease Control, National Health and Family Planning Commission of China is responsible for cancer surveillance in the entire country. Cancer registration data from each local registry located in each province are collected by NCCR annually to be analyzed and published to provide useful information for policy makers and cancer researchers.
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Turn-on Phosphorescent Chemodosimeter for Hg(2+) Based on a Cyclometalated Ir(III) Complex and Its Application in Time-Resolved Luminescence Assays and Live Cell Imaging.
Inorg Chem
PUBLISHED: 10-21-2014
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A novel "turn-on" phosphorescent chemodosimeter based on a cyclometalated Ir(III) complex has been designed and synthesized, which displays high selectivity and sensitivity toward Hg(2+) in aqueous media with a broad pH range of 4-10. Furthermore, by time-resolved photoluminescence techniques, some interferences from the short-lived background fluorescence can be eliminated effectively and the signal-to-noise ratio of the emission detection can be improved distinctly by using the chemodosimeter. Finally, the chemodosimeter can be used to monitor Hg(2+) effectively in living cells by confocal luminescence imaging.
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[The effect of oversized occluder on endothelialization after percutaneous closure of experimental atrial septal defect in dogs].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 10-21-2014
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To observe the effect of oversized occluder on endothelialization post percutaneous closure of experimental atrial septal defect (ASD) in dogs.
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[Dissolution testing combined with computer simulation technology to evaluate the bioequivalence of domestic amoxicillin capsule].
Yao Xue Xue Bao
PUBLISHED: 10-18-2014
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Re-evaluation of bioequivalence of generic drugs is one of the key research focus currently. As a means to ensure consistency of the therapeutic effectiveness of drug products, clinical bioequivalence has been widely accepted as a gold standard test. In vitro dissolution testing based on the theory of the BCS is the best alternative to in vivo bioequivalence study. In this article, the conventional dissolution method and flow-through cell method were used to investigate the dissolution profiles of domestic amoxicillin capsules in different dissolution media, and the absorption behavior of the drugs with different release rates (t85% = 15-180 min) in the gastrointestinal tract was predicted by Gastro Plus. The flow-through cell method was thought better to reflect the release characteristics in vivo, and amoxicillin capsules with regard to the release rates up to 45 min (t85% = 45 min) were having a satisfied bioequivalence with the oral solution according to the C(max) and AUC. Although two different dissolution profiles of domestic amoxicillin capsules were found by flow-through cell methods, prediction results revealed that domestic capsules were probably bioequivalent to each other.
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Dietary factors and risk of pancreatic cancer: a multi-centre case-control study in china.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-09-2014
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Pancreatic cancer is the sixth leading cause of cancer death with an increasing trend in China. Dietary intake is believed to play an important role in pancreatic cancer carcinogenesis. The aim of this paper was to evaluate associations between some dietary factors and risk of pancreatic cancer in a multi-centre case-control study conducted in China.
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Predictors and long-term outcome of seizures in human immuno-deficiency virus (HIV)-negative cryptococcal meningitis.
BMC Neurol
PUBLISHED: 10-06-2014
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Seizures are one of the most important neurologic complications of human immuno-deficiency virus (HIV)-negative cryptococcal meningitis. A better understanding of the risk associated factors can help predict those who will require treatment.
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Use of a simply modified drainage catheter for peritoneal dialysis treatment of acute renal failure associated with cardiac surgery in infants.
Medicine (Baltimore)
PUBLISHED: 09-26-2014
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Acute renal failure (ARF) is a common complication in infants who undergo cardiac surgery in the intensive care unit. We report on a modified drainage catheter used in peritoneal dialysis (PD) for the treatment of ARF associated with cardiac surgery in infants. Thirty-nine infants with congenital heart disease undergoing cardiac surgery who developed ARF at our center between January 2009 and January 2012 were assessed. A modified drainage catheter for PD was used in these infants. Their demographic, clinical, and surgical data were analyzed. Thirty infants with ARF were cured by PD, and the other 9 died in the first 48 hours because of the severity of the acute cardiac dysfunction. All these infants were dependent upon mechanical ventilation during the postoperative period and used vasoactive drugs. In the survival group, the interval between the procedure and initiation of PD was 13.6?±?6.5 (range, 6-30) hours. PD duration was 3.9?±?0.9 (3-6) days. Minor complications were encountered in some patients (asymptomatic hypokalemia, hyperglycemia, and thrombocytopenia). These complications were readily treated by drugs or resolved spontaneously. Hemodynamics, cardiac function, and renal function improved significantly during PD. These data suggest that PD using a modified drainage catheter for ARF after cardiac surgery in infants is safe, feasible, inexpensive, and yields good results.
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Dexmedetomidine attenuates hypoxemia during palliative reconstruction of the right ventricular outflow tract in pediatric patients.
Medicine (Baltimore)
PUBLISHED: 09-19-2014
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The objective of this study was to investigate whether the ? agonist dexmedetomidine has the ability to attenuate hypoxemia in pediatric patients undergoing palliative pulmonary artery reconstruction.From January 2009 to January 2013, a total of 25 pediatric patients with Tetralogy of Fallot, pulmonary atresia (ventricular septal defect), or persistent truncus arteriosus (I) were enrolled in our study. Due to hypoplastic pulmonary arteries, all patients received palliative pulmonary artery reconstruction. During the perioperative period, they were allocated to receive either dexmedetomidine (bolus dose of 0.3??g/kg followed by an infusion of 0.2-0.3??g/kg/h, n?=?15) or control drug (n?=?10) intravenously. Any desaturation was recorded. Heart rate, mean arterial pressure, pulse oximetry, and arterial blood gas parameters were measured during the perioperative period.There were no significant differences between the groups in hemodynamic variables. The arterial oxygen saturation and arterial blood gas parameters increased in the dexmedetomidine groups (P?
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The Potential of Indole and a Synthetic Derivative for PolyQ Aggregation Reduction by Enhancement of the Chaperone and Autophagy Systems.
ACS Chem Neurosci
PUBLISHED: 09-19-2014
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In polyglutamine (polyQ)-mediated disorders, the expansion of translated CAG repeats in the disease genes result in long polyQ tracts in their respective proteins, leading to intracellular accumulation of aggregated polyQ proteins, production of reactive oxygen species, and cell death. The molecular chaperones act in preventing protein misfolding and aggregation, thus inhibiting a wide range of harmful downstream events. In the circumstance of accumulation of aggregated polyQ proteins, the autophagic pathway is induced to degrade the misfolded or aggregated proteins. In this study, we used Flp-In 293/SH-SY5Y cells with inducible SCA3 ATXN3/Q75-GFP expression to test the effect of indole and synthetic derivatives for neuroprotection. We found that ATXN3/Q75 aggregation can be significantly prohibited in Flp-In 293 cells by indole and derivative NC001-8. Meanwhile, indole and NC001-8 up-regulated chaperones and autophagy in the same cell models. Both of them further promote neurite outgrowth in neuronal differentiated SH-SY5Y ATXN3/Q75-GFP cells. Our results demonstrate how indole and derivative NC001-8 are likely to work in reduction of polyQ-aggregation and provide insight into the possible effectual mechanism of indole compounds in polyQ spinocerebellar ataxia (SCA) patients. These findings may have therapeutic applications in a broad range of clinical situations.
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Indicators of perceived useful dementia care assistive technology: Caregivers' perspectives.
Geriatr Gerontol Int
PUBLISHED: 08-19-2014
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The study aims to investigate the caregivers' context-specific perceived usefulness of available assistive technology (AT) devices and the professionals' perspectives on the usefulness indicators of AT devices for home-dwelling individuals with mild-to-moderate dementia.
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A highly active beta-glucanase from a new strain of rumen fungus Orpinomyces sp.Y102 exhibits cellobiohydrolase and cellotriohydrolase activities.
Bioresour. Technol.
PUBLISHED: 08-08-2014
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A new strain of rumen fungus was isolated from Bos taurus, identified and designated Orpinomyces sp.Y102. A clone, celC7, isolated from the cDNA library of Orpinomyces sp.Y102, was predicted to encode a protein containing a signal peptide (Residues 1-17), an N-terminal dockerin-containing domain, and a C-terminal cellobiohydrolase catalytic domain of glycoside hydrolase family 6. CelC7 was insoluble when expressed in Escherichia coli. Deletion of 17 or 105 residues from the N-terminus significantly improved its solubility. The resulting enzymes, CelC7(-17) and CelC7(-105), were highly active to ?-glucan substrates and were stable between pH 5.0 and 11.0. CelC7(-105) worked as an exocellulase releasing cellobiose and cellotriose from acid-swollen Avicel and cellooligosaccharides, and displayed a Vmax of 6321.64?mole/min/mg and a Km of 2.18mg/ml to barley ?-glucan. Further, the crude extract of CelC7(-105) facilitated ethanol fermentation from cellulose. Thus, CelC7(-105) is a good candidate for industrial applications such as biofuel production.
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Nasopharyngeal carcinoma incidence and mortality in China in 2010.
Chin J Cancer
PUBLISHED: 08-07-2014
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Nasopharyngeal carcinoma (NPC) is common in South China. Although regional epidemiological data on NPC in China is available, national epidemiological data have been unavailable up to now. The goal of this study was to analyze the NPC incidence and mortality data in some domestic cancer registries, estimate these rates in China in 2010, and provide scientific information that can be harnessed for NPC control and prevention. To accomplish this goal, NPC incidence and mortality data for 2010 were collected from 145 Chinese cancer registries from which data were included in the 2013 National Cancer Registry Annual Report. Such indices as its incident and death numbers, crude rates, age-standardized rates and truncated rates were calculated and analyzed. The incidence and mortality in China and constituent areas were estimated according to the national population in 2010. An estimated 41,503 new cases and 20,058 deaths were attributed to NPC in China in 2010, accounting for 1.34% of all new cancer cases and 1.03% of all cancer-related deaths that year in China. Crude incidence and mortality were 3.16/100,000 and 1.53/100,000, respectively. World age-standardized incidence and mortality were 2.44/100,000 and 1.18/100,000, respectively. Incidence and mortality were higher among males than among females and slightly higher in urban areas than in rural areas. Among seven Chinese administrative regions, NPC incidence and mortality were obviously higher in South China than in other regions and lowest in North China. The male and female age-specific incidence and mortality both rose quickly from age 25-29 years, but peaked at different ages and varied by location. These results demonstrated that NPC incidence and mortality in China especially in South China were at high levels in the world, and suggested that control and prevention efforts should be enhanced.
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[Effect of mechanical tension on expressions of RhoA/Rho associated protein kinases in rat tendon stem cells in vitro].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 07-31-2014
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To investigate the effect of different mechanical tensions on the expressions of RhoA/Rho associated protein kinases (ROCK) in rat tendon stem cells (TSCs).
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Physical pretreatments of wastewater algae to reduce ash content and improve thermal decomposition characteristics.
Bioresour. Technol.
PUBLISHED: 07-28-2014
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Previous study showed high ash content in wastewater algae (WA) has a negative effect on bio-crude oil formation in hydrothermal liquefaction (HTL). This study explored the effect of different pretreatments on ash reduction and the thermal decomposition of WA. Single-stage (e.g. centrifugation) and two-stage pretreatments (e.g. centrifugation followed by ultrasonication, C+U) were used. The apparent activation energy of the thermal decomposition (E(a)) of pretreated algae was determined. HTL was conducted to study how different pretreatments may impact on bio-crude oil formation. Compared to untreated samples, the ash content of algae with centrifugation was reduced from 28.6% to 18.6%. With C+U pretreatments, E(a) was decreased from 50.2 kJ/mol to 35.9 kJ/mol and the bio-crude oil yield was increased from 30% to 55%. These results demonstrate that pretreatments of C+U can improve the thermal decomposition behavior of WA and enhance the bio-crude oil conversion efficiency.
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Uniaxial repetitive mechanical overloading induces influx of extracellular calcium and cytoskeleton disruption in human tenocytes.
Cell Tissue Res.
PUBLISHED: 07-11-2014
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Tendon calcification is common in the Achilles tendon, and injuries affect not only athletes, but also the general population. However, the underlying cellular mechanisms are not yet fully understood. In this study, we isolated healthy human tenocytes and subjected them to uniaxial mechanical stretching (at 1.0 Hz) for various stretch times (4 h, 8 h, 12 h) or magnitudes (0 %, 4 %, 8 %, 12 %). The extracellular calcium chelator EGTA, calcium channel inhibitor MnCl2, nifedipine, or various doses of exogenous calcium were administered to these cells with or without mechanical overloading. The intracellular calcium concentration was determined by using a Fluo-3/AM fluorescence probe, and the cytoskeleton was revealed by F-actin Phalloidin staining. The intracellular calcium concentration increased in a magnitude- and time-dependent manner following stretching. These increases were suppressed by EGTA, MnCl2, or nifedipine. Additionally, cytoskeleton F-actin was disrupted significantly by stretching in a time-dependent manner. When extracellular calcium was applied, the intracellular calcium concentration increased, and F-actin was disrupted dramatically under mechanical stretching compared with non-stretched cells. Thus, repetitive mechanical overloading induces the accumulation of abnormally high concentrations of intracellular calcium resulting from extracellular calcium influx mediated, at least in part, by membrane calcium channels and finally causes cytoskeleton disorganization and tenocyte dysfunction. These findings provide novel experimental evidence for the pathology of tendon calcification and indicate that the blockade of calcium influx is a potential target for the prevention and treatment of calcific tendinopathy.
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Incidence and mortality of liver cancer in China, 2010.
Chin J Cancer
PUBLISHED: 07-11-2014
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Liver cancer is a common malignant tumor in China and a major health concern. We aimed to estimate the liver cancer incidence and mortality in China in 2010 using liver cancer data from some Chinese cancer registries and provide reference for liver cancer prevention and treatment. We collected and evaluated the incidence and mortality data of liver cancer in 2010 from 145 cancer registries, which were included in the 2013 Chinese Cancer Registry Annual Report, calculated crude, standardized, and truncated incidences and mortalities, and estimated new liver cancer cases and deaths from liver cancer throughout China and in different regions in 2010 from Chinese practical population. The estimates of new liver cancer cases and deaths were 358,840 and 312,432, respectively, in China in 2010. The crude incidence, age-standardized rate by Chinese standard population (ASR China), and age-standardized rate by world standard population (ASR world) were 27.29/100,000, 21.35/100,000, and 20.87/100,000, respectively; the crude, ASR China, and ASR world mortalities were 23.76/100,000, 18.43/100,000, and 18.04/100,000, respectively. The incidence and mortality were the highest in western regions, higher in rural areas than in urban areas, and higher in males than in females. The age-specific incidence and mortality of liver cancer showed a rapid increase from age 30 and peaked at age 80-84 or 85+. Our results indicated that the 2010 incidence and mortality of liver cancer in China, especially in undeveloped rural areas and western regions, were among high levels worldwide. The strategy for liver cancer prevention and treatment should be strengthened.
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The incidences and mortalities of major cancers in China, 2010.
Chin J Cancer
PUBLISHED: 07-11-2014
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To estimate the cancer incidences and mortalities in China in 2010, the National Central Cancer Registry (NCCR) of China evaluated data for the year of 2010 from 145 qualified cancer registries covering 158,403,248 people (92,433,739 in urban areas and 65,969,509 in rural areas). The estimates of new cancer cases and cancer deaths were 3,093,039 and 1,956,622 in 2010, respectively. The percentage of morphologically verified cases were 67.11%; 2.99% of incident cases were identified through death certification only, with the mortality to incidence ratio of 0.61. The crude incidence was 235.23/100,000 (268.65/100,000 in males and 200.21/100,000 in females). The age-standardized rates by Chinese standard population (ASR China) and by world standard population (ASR world) were 184.58/100,000 and 181.49/100,000, respectively, with a cumulative incidence (0-74 years old) of 21.11%. The crude cancer mortality was 148.81/100,000 (186.37/100,000 in males and 109.42/100,000 in females). The ASR China and ASR world were 113.92/100,000 and 112.86/100,000, respectively, with a cumulative mortality of 12.78%. Lung, breast, gastric, liver, esophageal, colorectal, and cervical cancers were the most common cancers. Lung, liver, gastric, esophageal, colorectal, breast, and pancreatic cancers were the leading causes of cancer deaths. The coverage of cancer registration has rapidly increased in China in recent years and may reflect more accurate cancer burdens among populations living in different areas. Given the increasing cancer burden in the past decades, China should strengthen its cancer prevention and control.
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Molecular kinetics. Ras activation by SOS: allosteric regulation by altered fluctuation dynamics.
Science
PUBLISHED: 07-05-2014
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Activation of the small guanosine triphosphatase H-Ras by the exchange factor Son of Sevenless (SOS) is an important hub for signal transduction. Multiple layers of regulation, through protein and membrane interactions, govern activity of SOS. We characterized the specific activity of individual SOS molecules catalyzing nucleotide exchange in H-Ras. Single-molecule kinetic traces revealed that SOS samples a broad distribution of turnover rates through stochastic fluctuations between distinct, long-lived (more than 100 seconds), functional states. The expected allosteric activation of SOS by Ras-guanosine triphosphate (GTP) was conspicuously absent in the mean rate. However, fluctuations into highly active states were modulated by Ras-GTP. This reveals a mechanism in which functional output may be determined by the dynamical spectrum of rates sampled by a small number of enzymes, rather than the ensemble average.
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A clinical study of thoracoscopy-assisted mitral valve replacement concomitant with tricuspid valvuloplasty, with domestically manufactured pipeline products for cardiopulmonary bypass.
J Cardiothorac Surg
PUBLISHED: 06-21-2014
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To discuss the feasibility and experience of treating valvular heart diseases with thoracoscopy-assisted mitral valve replacement concomitant with tricuspid valvuloplasty, with domestically manufactured pipeline products for cardiopulmonary bypass.
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Growth Hormone Deficiency in a Dopa-Responsive Dystonia Patient With a Novel Mutation of Guanosine Triphosphate Cyclohydrolase 1 Gene.
J. Child Neurol.
PUBLISHED: 06-19-2014
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Dopa-responsive dystonia is a rare hereditary movement disorder caused by mutations in the guanosine triphosphate cyclohydrolase 1 (GCH1) gene. This disease typically manifests in dystonia, with marked diurnal fluctuation and a dramatic response to levodopa. However, growth retardation in dopa-responsive dystonia has rarely been reported, and the etiology of short stature is not clarified. Here, we report a 14-year-old patient with extremities dystonia and short stature. Treatment with levodopa relieved his symptoms and resulted in a height increase. We also investigated the mutation in GCH1 and the etiology of short stature in this case. Sequence analysis of GCH1 revealed a novel mutation (c.695G>T). Laboratory examinations and imaging confirmed the diagnosis of growth hormone deficiency. We conclude that our case reveals a rare feature for dopa-responsive dystonia and suggests a possible pathogenic link between growth hormone deficiency and dopa-responsive dystonia. We recommend levodopa as the first choice for treating dopa-responsive dystonia in children with growth hormone deficiency.
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Validation of the Pangao PG-800B5 for clinical use and self-measurement according to the European Society of Hypertension International Protocol revision 2010.
Blood Press Monit
PUBLISHED: 06-13-2014
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This study aimed to validate the Pangao PG-800B5 upper arm blood pressure monitor according to the European Society of Hypertension International Protocol revision 2010.
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Breast cancer in China.
Lancet Oncol.
PUBLISHED: 05-30-2014
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The health burden of cancer is increasing in China, with more than 1·6 million people being diagnosed and 1·2 million people dying of the disease each year. As in most other countries, breast cancer is now the most common cancer in Chinese women; cases in China account for 12·2% of all newly diagnosed breast cancers and 9·6% of all deaths from breast cancer worldwide. China's proportional contribution to global rates is increasing rapidly because of the population's rising socioeconomic status and unique reproductive patterns. In this Review we present an overview of present control measures for breast cancer across China, and emphasise epidemiological and socioeconomic diversities and disparities in access to care for various subpopulations. We describe demographic differences between China and high-income countries, and also within geographical and socioeconomic regions of China. These disparities between China and high-income countries include younger age at onset of breast cancer; the unique one-child policy; lower rates of provision and uptake for screening for breast cancer; delays in diagnosis that result in more advanced stage of disease at presentation; inadequate resources; and a lack of awareness about breast cancer in the Chinese population. Finally, we recommend key measures that could contribute to improved health outcomes for patients with breast cancer in China.
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Engineering a light-regulated GABAA receptor for optical control of neural inhibition.
ACS Chem. Biol.
PUBLISHED: 05-22-2014
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Optogenetics has become an emerging technique for neuroscience investigations owing to the great spatiotemporal precision and the target selectivity it provides. Here we extend the optogenetic strategy to GABAA receptors (GABAARs), the major mediators of inhibitory neurotransmission in the brain. We generated a light-regulated GABAA receptor (LiGABAR) by conjugating a photoswitchable tethered ligand (PTL) onto a mutant receptor containing the cysteine-substituted ?1-subunit. The installed PTL can be advanced to or retracted from the GABA-binding pocket with 500 and 380 nm light, respectively, resulting in photoswitchable receptor antagonism. In hippocampal neurons, this LiGABAR enabled a robust photoregulation of inhibitory postsynaptic currents. Moreover, it allowed reversible photocontrol over neuron excitation in response to presynaptic stimulation. LiGABAR thus provides a powerful means for functional and mechanistic investigations of GABAAR-mediated neural inhibition.
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Targeted deletion of ER chaperone GRP94 in the liver results in injury, repopulation of GRP94-positive hepatocytes, and spontaneous hepatocellular carcinoma development in aged mice.
Neoplasia
PUBLISHED: 05-20-2014
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Hepatocellular carcinoma (HCC) often results from chronic liver injury and severe fibrosis or cirrhosis, but the underlying molecular pathogenesis is unclear. We previously reported that deletion of glucose regulated protein 94 (GRP94), a major endoplasmic reticulum chaperone, in the bone marrow and liver leads to progenitor/stem cell expansion. Since liver progenitor cell (LPC) proliferation can contribute to liver tumor formation, here we examined the effect of GRP94 deficiency on spontaneous liver tumorigenesis. Utilizing liver-specific Grp94 knockout mice driven by Albumin-Cre (cGrp94(f/f)), we discovered that while wild-type livers are tumor free up to 24 months, cGrp94(f/f) livers showed abnormal small nodules at 15 months and developed HCC and ductular reactions (DRs) by 21 months of age, associating with increased liver injury, apoptosis and fibrosis. cGrp94(f/f) livers were progressively repopulated by GRP94-positive hepatocytes. At 15 months, we observed expansion of LPCs and mild DRs, as well as increase in cell proliferation. In examining the underlying mechanisms for HCC development in cGrp94(f/f) livers, we detected increase in TGF-?1, activation of SMAD2/3, ERK, and JNK, and cyclin D1 upregulation at the premalignant stage. While epithelial-mesenchymal transition (EMT) was not evident, E-cadherin expression was elevated. Correlating with the recurrence of GRP94 positive-hepatocytes, the HCC was found to be GRP94-positive, whereas the expanded LPCs and DRs remained GRP94-negative. Collectively, this study uncovers that GRP94 deficiency in the liver led to injury, LPC expansion, increased proliferation, activation of oncogenic signaling, progressive repopulation of GRP94-positive hepatocytes and HCC development in aged mice.
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A prospective study of midfoot osteotomy combined with adjacent joint sparing internal fixation in treatment of rigid pes cavus deformity.
J Orthop Surg Res
PUBLISHED: 05-19-2014
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Midfoot osteotomy has been previously confirmed to be a good method to correct pes cavus. How to fix the osteotomy and which point to choose for the procedure has been a focus for most surgeons. The aim of this study was to analyse the outcomes of a series of patients who had been treated for pes cavus deformity using midfoot osteotomy combined with adjacent joint sparing internal fixation.
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Downregulation of SUN2, a novel tumor suppressor, mediates miR-221/222-induced malignancy in central nervous system embryonal tumors.
Carcinogenesis
PUBLISHED: 05-15-2014
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Embryonal tumors of the central nervous system represent a highly malignant tumor group of medulloblastoma (MB), atypical teratoid/rhabdoid tumor (AT/RT) and primitive neuroectodermal tumor that frequently afflict children. AT/RT is often misdiagnosed as MB/primitive neuroectodermal tumor but with higher recurrence and lower survival rates. Pathogenesis of AT/RT is largely unknown. In this study, we report both the miRNome and transcriptome traits in AT/RT and MB by using small RNA sequencing and gene expression microarray analyses. Our findings demonstrate that the miR-221/222-encoded micro RNAs are abundantly expressed in AT/RT but not in MB, which contribute substantially to the malignancy of embryonal tumors. miR-221/222 targeted SUN2, a newly discovered tumor suppressor, directly to increase cell proliferation and tumor malignancy in vitro and in vivo. Immunohistochemistry against SUN2 in a tissue microarray of 33 AT/RT and 154 MB tumor specimens also detected less SUN2 protein in AT/RT. Collectively, this study uncovers a novel tumor suppressor, SUN2, plays a critical role in miR-221/222-mediated AT/RT malignancy as well as supports miR-221/222 and SUN2 represent new promising targets for more active therapies in AT/RT. In addition, our miRNome and transcriptome data also provide a roadmap for further embryonal tumor research.
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Neovascular glaucoma after central retinal vein occlusion in pre-existing glaucoma.
BMC Ophthalmol
PUBLISHED: 05-06-2014
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To determine the outcome of central retinal vein occlusion (CRVO) in pre-existing glaucoma and the predisposing factors of developing neovascular glaucoma (NVG).
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[Trend analysis of cervical cancer incidence and mortality rates in Chinese women during 1989-2008].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 05-06-2014
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To evaluate the trend of cervical cancer incidence and mortality rates during 1989-2008 in Chinese women,so as to inform the development of relevant policies and strategies in China.
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Total arch repair for acute type a aortic dissection with open placement of a modified triple-branched stent graft and the arch open technique.
J Cardiothorac Surg
PUBLISHED: 04-16-2014
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BackgroundIn total arch repair with open placement of a triple-branched stent graft for acute type A aortic dissection, the diameters of the native arch vessels and the distances between 2 neighboring arch vessels did not always match the available sizes of the triple-branched stent grafts, and insertion of the triple-branched stent graft through the distal ascending aortic incision was not easy in some cases. To reduce those two problems, we modified the triple-branched stent graft and developed the arch open technique.Methods and resultsTotal arch repair with open placement of a modified triple-branched stent graft and the arch open technique was performed in 25 consecutive patients with acute type A aortic dissection. There was 1 surgical death. Most survivors had an uneventful postoperative course. All implanted stents were in a good position and wide expansion, there was no space or blood flow surrounding the stent graft. Complete thrombus obliteration of the false lumen was found around the modified triple-branched stent graft in all survivors and at the diaphragmatic level in 20 of 24 patients.ConclusionsThe modified triple-branched stent graft could provide a good match with the different diameters of the native arch vessels and the various distances between 2 neighboring arch vessels, and it¿s placement could become much easier by the arch open technique. Consequently, placement of a modified triple-branched stent graft could be easily used in most patients with acute type A aortic dissection for effective total arch repair.
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Verification of wild-type EGFR status in non-small cell lung carcinomas using a mutant-enriched PCR on selected cases.
J Mol Diagn
PUBLISHED: 04-10-2014
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EGFR genotyping is required for targeted therapy of lung adenocarcinoma. Because a false-negative result might prevent a patient from receiving appropriate targeted therapies, it is desirable to recheck equivocal results of EGFR genotyping. A cohort of 346 lung cancers was tested with a commercial kit for EGFR mutations; nine of the cases had upward real-time amplification curves at late cycles. They were also investigated using mutant-enriched PCR with peptide nucleic acid-locked nucleic acid (PNA-sequencing). Six of the nine equivocal cases harbored EGFR mutations. These cases likely had a small amount of mutant DNA near the detection limit of the commercial kit. Twenty nonequivocal, wild-type cases were reconfirmed using PNA-sequencing. We noticed a College of American Pathologists proficiency test material that showed a suspicious upward curve and eventually proved to have an H773_V774insPH in exon 20, for which a specific primer was not designed in the commercial kit. Further study using cloned DNA fragments showed that the upward curve most likely resulted from cross-reaction between similar, but nonidentical, sequences. It is desirable to keep the number of false-negative results as low as possible, but rechecking all wild-type cases is impractical. The late upward curves we observed helped identify suspicious cases for rechecking. A second method, such as PNA-sequencing, is recommended to verify wild-type cases.
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Regulation of Rac1 translocation and activation by membrane domains and their boundaries.
J. Cell. Sci.
PUBLISHED: 04-02-2014
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The activation of Rac1 and related Rho GTPases involves dissociation from Rho GDP-dissociation inhibitor proteins and translocation to membranes, where they bind effectors. Previous studies have suggested that the binding of Rac1 to membranes requires, and colocalizes with, cholesterol-rich liquid-ordered (lo) membrane domains (lipid rafts). Here, we have developed a fluorescence resonance energy transfer (FRET) assay that robustly detects Rac1 membrane targeting in living cells. Surprisingly, FRET with acceptor constructs that were targeted to either raft or non-raft areas indicated that Rac1 was present in both regions. Functional studies showed that Rac1 localization to non-raft regions decreased GTP loading as a result of inactivation by GTPase-activating proteins. In vitro, Rac1 translocation to supported lipid bilayers also required lo domains, yet Rac1 was concentrated in the liquid-disordered (ld) phase. Single-molecule analysis demonstrated that translocation occurred preferentially at lo-ld boundaries. These results, therefore, suggest that Rac1 translocates to the membrane at domain boundaries, then diffuses into raft and non-raft domains, which controls interactions. These findings resolve discrepancies in our understanding of Rac biology and identify novel mechanisms by which lipid rafts modulate Rho GTPase signaling.
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Safety and Efficacy of Rasagiline in Addition to Levodopa for the Treatment of Idiopathic Parkinson's Disease: A Meta-Analysis of Randomised Controlled Trials.
Eur. Neurol.
PUBLISHED: 03-31-2014
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Background: To assess the safety and efficacy of rasagiline for the treatment of Parkinson's disease (PD) among individuals currently receiving levodopa. Methods: A systematic literature search was conducted to identify randomised controlled trials (RCT) comparing rasagiline with placebo/no treatment in individuals with PD currently receiving levodopa. Outcome measures included improvement in motor functions; symptomatic improvement; improvement in quality of life; adverse effects. Random-effect meta-analytical techniques were conducted for the outcome measure and subgroup analyses. Results: Three RCTs were included (n = 1002). The results showed significantly greater improvements in daily 'on' time without dyskinesia in levodopa-treated participants with idiopathic PD receiving 1 mg/day rasagiline compared to placebo (n = 712, 2 RCTs, MD 0.80, CI 0.45 to 1.15; p < 0.00001), and significantly greater improvements in Unified Parkinson's Disease Rating Scale motor performance scores during 'on' time in participants receiving 0.5-1 mg/day rasagiline (0.5 mg/day: n = 282, MD -2.91, CI -4.59 to -1.23; p = 0.0007; 1 mg/day: n = 712, 2 RCTs, MD -2.91, CI -4.02 to -1.80; p < 0.00001). There were no significant differences in adverse effects. Conclusion: 0.5 to 1 mg/day rasagiline in addition to levodopa is a safe and well-tolerated combination therapy for individuals with Parkinson's disease. © 2014 S. Karger AG, Basel.
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Immunohistochemical localization of DPP10 in rat brain supports the existence of Kv4/KChIP/DPPL ternary complex in neurons.
J. Comp. Neurol.
PUBLISHED: 03-31-2014
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Subthreshold A-type K(+) currents (ISA s) have been recorded from the cell bodies of hippocampal and neocortical interneurons as well as neocortical pyramidal neurons. Kv4 channels are responsible for the somatodendritic ISA s. It has been proposed that neuronal Kv4 channels are ternary complexes including pore-forming Kv4 subunits, K(+) channel-interacting proteins (KChIPs), and dipeptidyl peptidase-like proteins (DPPLs). However, colocalization evidence was still lacking. The distribution of DPP10 mRNA in rodent brain has been reported but its protein localization remains unknown. In this study, we generated a DPP10 antibody to label DPP10 protein in adult rat brain by immunohistochemistry. Absent from glia, DPP10 proteins appear mainly in the cell bodies of DPP10(+) neurons, not only at the plasma membrane but also in the cytoplasm. At least 6.4% of inhibitory interneurons in the hippocampus coexpressed Kv4.3, KChIP1 and DPP10, with the highest density in the CA1 strata alveus/oriens/pyramidale and the dentate hilus. Colocalization of Kv4.3/KChIP1/DPP10 was also detected in at least 6.9% of inhibitory interneurons scattering throughout the neocortex. Both hippocampal and neocortical Kv4.3/KChIP1/DPP10(+) inhibitory interneurons expressed parvalbumin or somatostain, but not calbindin or calretinin. Furthermore, we found colocalization of Kv4.2/Kv4.3/KChIP3/DPP10 in neocortical layer 5 pyramidal neurons and olfactory bulb mitral cells. Together, although DPP10 is also expressed in some brain neurons lacking Kv4 (such as parvalbumin- and somatostatin-positive Golgi cells in the cerebellum), colocalization of DPP10 with Kv4 and KChIP at the plasma membrane of ISA -expressing neuron somata supports the existence of Kv4/KChIP/DPPL ternary complex in vivo. J. Comp. Neurol., 2014. © 2014 Wiley Periodicals, Inc.
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Expressions of p16 and p27 in urothelial carcinoma and their prognostic value.
Kaohsiung J. Med. Sci.
PUBLISHED: 03-16-2014
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Expressions of human p16 and p27 were tested for correlations with clinicopathologic features of urothelial carcinoma (UC). Tissue microarrays (TMA) constructed from paraffin-embedded specimens from 78 patients with UC were analyzed by immunohistochemical staining. In 49 of the 78 tumors (63%), high p16 expression was associated with absence of tumor invasiveness and low-grade carcinoma (p = 0.003 and p = 0.046, respectively). The p27 expression was high in 33 of the 78 tumors (42%) and showed a significant negative association with invasiveness, carcinoma grade, and tumor size (p = 0.016, p = 0.046, and p = 0.014, respectively). Kaplan-Meier analysis indicated that patients with high p27 levels had longer than average overall survival (p = 0.021). This study demonstrates that p16 and p27 are prognostic indicators of tumor stage and grade in UC and that they provide clinicians with the ancillary information needed for selecting suitable therapeutic strategies.
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Epidemiological patterns of cancer incidence in southern China: based on 6 population-based cancer registries.
Asian Pac. J. Cancer Prev.
PUBLISHED: 03-11-2014
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The epidemiological patterns of cancer incidence have been investigated widely in western countries. Nevertheless, information is quite limited in Jiangxi province, southern China.
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Aqueous extract of Glycyrrhiza inflata inhibits aggregation by upregulating PPARGC1A and NFE2L2-ARE pathways in cell models of spinocerebellar ataxia 3.
Free Radic. Biol. Med.
PUBLISHED: 03-05-2014
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Spinocerebellar ataxia (SCA) types 1, 2, 3, 6, 7, and 17 and dentatorubropallidoluysian atrophy, as well as Huntington disease, are a group of neurodegenerative disorders caused by a CAG triplet-repeat expansion encoding a long polyglutamine (polyQ) tract in the respective mutant proteins. The cytoplasmic and nuclear aggregate formation, a pathological hallmark of polyQ diseases, is probably the initial process triggering the subsequent pathological events. Compromised oxidative stress defense capacity and mitochondrial dysfunction have emerged as contributing factors to the pathogenesis of polyQ diseases. The roots of licorice (Glycyrrhiza species) have long been used as an herbal medicine. In this study, we demonstrate the aggregate-inhibitory effect of Glycyrrhiza inflata herb extract and its constituents licochalcone A and ammonium glycyrrhizinate (AMGZ) in both 293 and SH-SY5Y ATXN3/Q75 cells, SCA3 cell models. The reporter assay showed that G. inflata herb extract, licochalcone A, and AMGZ could enhance the promoter activity of peroxisome proliferator-activated receptor ?, coactivator 1? (PPARGC1A), a known regulator of mitochondrial biogenesis and antioxidative response genes. G. inflata extract, licochalcone A, and AMGZ upregulated PPARGC1A expression and its downstream target genes, SOD2 and CYCS, in the 293 ATXN3/Q75 cell model. The expression of nuclear factor erythroid 2-related factor 2 (NFE2L2), the principal transcription factor that binds to antioxidant-responsive elements (AREs) to promote ARE-dependent gene expression when the cells respond to oxidative stress, and its downstream genes, HMOX1, NQO1, GCLC, and GSTP1, was also increased by G. inflata herb extract, licochalcone A, and AMGZ. Knockdown of PPARGC1A increased aggregates in ATXN3/Q75 cells and also attenuated the aggregate-inhibiting effect of the tested compounds. G. inflata extract and its constituents significantly elevated GSH/GSSG ratio and reduced reactive oxidative species in ATXN3/Q75 cells. The study results suggest that the tested agents activate PPARGC1A activity and NFE2L2-ARE signaling to increase mitochondrial biogenesis, decrease oxidative stress, and reduce aggregate formation in SCA3 cellular models.
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Time trends of ovarian cancer incidence in China.
Asian Pac. J. Cancer Prev.
PUBLISHED: 02-18-2014
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The aim of this study was to examine the trend of ovary cancer incidence from 1999 to 2010 in China and predict the burden up to 2020. Crude incidence, age specific incidence and age-adjusted incidence rates were calculated. Joinpoint regression was performed to obtain estimated annual percentages and Bayesian age-period- cohort modeling was used to predict the incidence rate until the year 2020. In China, the crude rate of ovary cancer was 7.91/100,000 and the age-adjusted rate was 5.35/100,000 overall during period 1999-2010. The rates in urban regions were higher than in rural regions. A significant rising trend during 1999-2006 was followed by a drop during 2006-2010 in age-adjusted rates for urban females. In contrast, constant rise was observed in rural women. The decrease in ovary cancer of urban areas tended to be restricted to women aged 50 years and younger. In contrast, increases of ovary cancer in rural areas appeared in virtually all age groups. Although the age-adjusted incidence rate for ovary cancer was predicted to be reduced after year 2011, the crude rate was likely to be relative stable up to 2020. The burden of ovary cancer in China will continue to be relative stable due to the aging population.
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Variant R244H in Na+/Mg2+ exchanger SLC41A1 in Taiwanese Parkinson's disease is associated with loss of Mg2+ efflux function.
Parkinsonism Relat. Disord.
PUBLISHED: 02-11-2014
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Sequence variants in SLC41A1 have been reported to be associated with Parkinson's disease (PD). This study investigates whether the genetic variants in SLC41A1 contribute to Taiwanese PD.
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Differential hypermethylation of death-associated protein kinase promoter in central neurocytoma and oligodendroglioma.
Biomed Res Int
PUBLISHED: 02-10-2014
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Central neurocytoma and oligodendroglioma are rare tumors of the central nervous system. However, diagnosis between these two types of tumors is challenging due to their many cytological and histological similarities. Death-associated protein kinase (DAPK) is a calcium/calmodulin-regulated serine/threonine protein kinase involved in many apoptosis pathways, and repressed expression of DAPK by promoter hypermethylation has been found in a variety of human cancers. The purpose of this study was to assess DAPK protein expression and promoter hypermethylation in central neurocytoma and oligodendroglioma.
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H-Ras forms dimers on membrane surfaces via a protein-protein interface.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-10-2014
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The lipid-anchored small GTPase Ras is an important signaling node in mammalian cells. A number of observations suggest that Ras is laterally organized within the cell membrane, and this may play a regulatory role in its activation. Lipid anchors composed of palmitoyl and farnesyl moieties in H-, N-, and K-Ras are widely suspected to be responsible for guiding protein organization in membranes. Here, we report that H-Ras forms a dimer on membrane surfaces through a protein-protein binding interface. A Y64A point mutation in the switch II region, known to prevent Son of sevenless and PI3K effector interactions, abolishes dimer formation. This suggests that the switch II region, near the nucleotide binding cleft, is either part of, or allosterically coupled to, the dimer interface. By tethering H-Ras to bilayers via a membrane-miscible lipid tail, we show that dimer formation is mediated by protein interactions and does not require lipid anchor clustering. We quantitatively characterize H-Ras dimerization in supported membranes using a combination of fluorescence correlation spectroscopy, photon counting histogram analysis, time-resolved fluorescence anisotropy, single-molecule tracking, and step photobleaching analysis. The 2D dimerization Kd is measured to be ?1 × 10(3) molecules/µm(2), and no higher-order oligomers were observed. Dimerization only occurs on the membrane surface; H-Ras is strictly monomeric at comparable densities in solution. Analysis of a number of H-Ras constructs, including key changes to the lipidation pattern of the hypervariable region, suggest that dimerization is a general property of native H-Ras on membrane surfaces.
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Age-related reduction in calbindin?D28K expression in the Sprague-Dawley rat lens.
Mol Med Rep
PUBLISHED: 01-20-2014
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Calcium levels in the lens rise with increasing age and increased intracellular calcium accumulation is known to be a risk factor for cataract formation. Calbindin?D28K (CALB1) is an intracellular calcium buffer. It is not clear whether CALB1 levels change in response to the Ca2+ accumulation in the lens that occurs with age. The present study investigated the distribution of CALB1 in the lenses of Sprague?Dawley (SD) rats and whether this changed with age. Lenses were isolated from SD rats at 1, 6, 12 and 18 months of age. CALB1 distribution was examined using immunohistochemistry. Lens epithelial cells were counted in median sagittal plane slices from the hematoxylin and eosin?stained lens and quantified using western blot analysis. Calb1 gene expression was examined using reverse transcription?quantitative polymerase chain reaction. CALB1 was distributed in the epithelial and fiber cells of the lens. CALB1 levels declined significantly with increasing age, whilst there was no significant accompanying decrease in the number of lens cells. A similar reduction was noted in CALB1 mRNA levels. To the best of our knowledge, this is the first study to demonstrate that CALB1 expression and CALB1 protein levels in SD rat lens decrease with age. This reduction does not reflect a reduction in lens cell numbers but a genuine reduction in gene expression within these cells. Thus, CALB1 may be important in changes occurring in the lens in older age, in particular in the development of cataracts.
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Aqueous extract of Gardenia jasminoides targeting oxidative stress to reduce polyQ aggregation in cell models of spinocerebellar ataxia 3.
Neuropharmacology
PUBLISHED: 01-18-2014
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Spinocerebellar ataxias (SCAs), caused by expanded CAG repeats encoding a long polyglutamine (polyQ) tract in the respective proteins, are characterized by the accumulation of intranuclear and cytoplasmic misfolded polyQ aggregation that leads to cell death. Suppression of aggregate formation can inhibit a wide range of downstream pathogenic events and is expected to be a therapeutic strategy for SCAs. Here we show the anti-aggregation potential of Gardenia jasminoides (G. jasminoides) and its components/metabolite geniposide, crocin, and genipin, in ATXN3/Q75-GFP 293 cells, a putative SCA3 cell model. We found the aggregation can be significantly prohibited by G. jasminoides, genipin, geniposide and crocin. Meanwhile, G. jasminoides, genipin, geniposide, and crocin up-regulated anti-oxidative markers NFE2L2, NQO1, GCLC and GSTP1, and reduced the production of reactive oxidative species (ROS) in the same cell models. All of them further inhibited the aggregation in neurally differentiated SH-SY5Y ATXN3/Q75-GFP cells. Our results demonstrate that G. jasminoides, genipin, geniposide and crocin work on polyQ-aggregation reduction by suppressing ROS. These findings indicate the therapeutic applications of G. jasminoides in treating SCAs. Furthermore, oxidative stress inhibition could be a good target for drug development of anti-polyQ aggregation.
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Paroxysmal kinesigenic dyskinesia and myotonia congenita in the same family: coexistence of a PRRT2 mutation and two CLCN1 mutations.
Neurosci Bull
PUBLISHED: 01-16-2014
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Paroxysmal kinesigenic dyskinesia (PKD) and myotonia congenita (MC) are independent disorders that share some clinical features. We aimed to investigate the sequences of PRRT2 and CLCN1 in a proband diagnosed with PKD and suspected MC. Clinical evaluation and auxiliary examinations were performed. Direct sequencing of the entire coding regions of the PRRT2 and CLCN1 genes was conducted. Haplotype analysis confirmed the relationships among the family members. The proband suffered choreoathetosis attacks triggered by sudden movements, and lower-limb weakness and stiffness that worsened in cold weather. Carbamazepine monotherapy completely controlled his choreoathetosis and significantly relieved his limb weakness and stiffness. His father, when young, had similar limb stiffness, while his mother and brother were asymptomatic. Genetic analysis revealed that the proband and his father harbored a PRRT2 c.649dupC mutation, and CLCN1 c.1723C>T and c.2492A>G mutations. His brother carried only the two CLCN1 mutations. None of these mutations were identified in his mother and 150 unrelated controls. This is the first report showing the coexistence of PRRT2 and CLCN1 mutations. Our results also indicate that both the PRRT2 and CLCN1 genes need to be screened if we fail to identify PRRT2 mutations in PKD patients or CLCN1 mutations in MC patients.
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Poly(Ethylene glycol) as a scaffold for high-affinity open-channel blockers of the mouse nicotinic acetylcholine receptor.
PLoS ONE
PUBLISHED: 01-01-2014
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High-affinity blockers for an ion channel often have complex molecular structures that are synthetically challenging and/or laborious. Here we show that high-affinity blockers for the mouse nicotinic acetylcholine receptor (AChR) can be prepared from a structurally simple material, poly(ethylene glycol) (PEG). The PEG-based blockers (PQ1-5), comprised of a flexible octa(ethylene glycol) scaffold and two terminal quaternary ammonium groups, exert low- to sub-micromolar affinities for the open AChR pore (measured via single-channel analysis of AChRs expressed in human embryonic kidney cells). PQ1-5 are comparable in pore-binding affinity to the strongest AChR open-channel blockers previously reported, which have complex molecular structures. These results suggest a general approach for designing potent open-channel blockers from a structurally flexible polymer. This design strategy involves simple synthetic procedures and does not require detailed information about the structure of an ion-channel pore.
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Indole and synthetic derivative activate chaperone expression to reduce polyQ aggregation in SCA17 neuronal cell and slice culture models.
Drug Des Devel Ther
PUBLISHED: 01-01-2014
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In spinocerebellar ataxia type 17 (SCA17), the expansion of a translated CAG repeat in the TATA box binding protein (TBP) gene results in a long polyglutamine (polyQ) tract in the TBP protein, leading to intracellular accumulation of aggregated TBP and cell death. The molecular chaperones act in preventing protein aggregation to ameliorate downstream harmful events. In this study, we used Tet-On SH-SY5Y cells with inducible SCA17 TBP/Q79-green fluorescent protein (GFP) expression to test indole and synthetic derivative NC001-8 for neuroprotection. We found that indole and NC001-8 up-regulated chaperone expression to reduce polyQ aggregation in neuronal differentiated TBP/Q79 cells. The effects on promoting neurite outgrowth and on reduction of aggregation on Purkinje cells were also confirmed with cerebellar primary and slice cultures of SCA17 transgenic mice. Our results demonstrate how indole and derivative NC001-8 reduce polyQ aggregation to support their therapeutic potentials in SCA17 treatment.
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Discrepant expression of cytokines in inflammation- and age-related cataract patients.
PLoS ONE
PUBLISHED: 01-01-2014
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Inflammatory cataracts secondary to Behcet's disease (BD) or Vogt-Koyanagi-Harada disease (VKH) are thought to result from a pathological dysregulation of cytokines that is different from that of age-related (AR) cataracts. However, little is known about the function of cytokines in the development of inflammatory cataracts. The purpose of this study was to identify possible differences in cytokine expression in inflammation- and age-related cataract patients.
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Congenital cataract: prevalence and surgery age at Zhongshan Ophthalmic Center (ZOC).
PLoS ONE
PUBLISHED: 01-01-2014
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Congenital cataract (CC) is the primary cause of treatable childhood blindness. Population-based assessments of prevalence and surgery age of CC, which are critical for improving management strategies, have been unavailable in China until now. We conducted a hospital-based, cross-sectional study of the hospital charts of CC patients younger than 18 years old from January 2005 to December 2010 at Zhongshan Ophthalmic Center (ZOC) in Guangzhou, China. Residence, gender, age at surgery, hospitalization time, and the presence of other ocular abnormalities were extracted and statistically analyzed in different subgroups. The search identified 1314 patients diagnosed with CC from a total of 136154 hospitalizations, which accounted for 2.39% of all the cataract in-patients and 1.06% of the total in-patients over the six-year study period. Of the identified CC patients, 9.2% had ? 2 hospitalizations due to the necessity of additional surgeries, with a total ratio of boys to girls of 1.75 ? 1. Based on a subgroup analysis according to age, patients 2-6 years old constituted the highest proportion (29.22%) of all hospitalized CC patients, and those 13-18 years old constituted the lowest proportion (13.47%) of the total number. The average age at surgery was 27.62 ± 23.36 months, but CC patients ? 6 years old (especially ? 6 months old) became increasingly prevalent throughout the 6-year study period. A total of 276 cases (20.93%) of CC were associated with one or more other ocular abnormalities, the highest incidence rates were observed for exotropia (6.24%), nystagmus (6.16%), and refractive error (3.65%). In conclusion, CC patients accounted for 2.39% of all cataract in-patients in a review of 6 years of hospitalization charts from ZOC. The age at the time of surgery decreased over the 6-year study period, which probably reflects the continuing improvement of public awareness of children's eye care in China.
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[Population-attributable risk estimates for breast cancer in Chinese females].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 12-30-2013
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To estimate the contribution of known identified risk factors to breast cancer incidence and mortality in China, and provide evidence to support the prevention and control of breast cancer for Chinese females.
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[Incidence and mortality of oralcavity and pharyngeal cancer in China, 2009].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 12-06-2013
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To analyze the incidence and mortality of oral cavity and pharyngeal cancer in cancer-registration areas of China in 2009.
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Melanin bleaching with dilute hydrogen peroxide: a simple and rapid method.
Appl. Immunohistochem. Mol. Morphol.
PUBLISHED: 09-27-2013
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Melanins are naturally occurring pigments in both normal and pathologic tissues. Two common bleaching processes are potassium permanganate followed by oxalic acid treatment and dilute hydrogen peroxide (H2O2) process. The potassium permanganate/oxalic acid method is faster and more easily incorporated in conventional daily immunostaining protocols, whereas the dilute H2O2 method requires 24 hours. This study aimed to reduce melanin bleaching time by using a 10% H2O2 dilution. First, reaction time was reduced to 30 minutes by raising the temperature to 65°C. Second, containers with high thermal conductivity were used to improve bleaching effectiveness. Experimental comparisons of melanin treatments with H2O2 contained in an iron jar, a glass coplin jar, and a plastic steel jar obtained bleaching time of 20, 30, and 40 minutes, respectively. These modifications of the conventional bleaching method significantly improve the speed and efficiency of the procedure and are recommended when performing immunohistochemical studies.
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Variations of IGHMBP2 Gene Was Not the Major Cause of Han Chinese Patients With Non-5q-Spinal Muscular Atrophies.
J. Child Neurol.
PUBLISHED: 09-09-2013
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Spinal muscular atrophy with respiratory distress type 1 (SMARD1), a notably common form of non-5q-spinal muscular atrophy, can be confused with infantile spinal muscular atrophy and is characterized by the early onset of diaphragmatic palsy and predominantly distal muscle weakness. The defective gene, immunoglobulin mu-binding protein 2 (IGHMBP2), is located on chromosome 11q13-q21. In this study, we screened the IGHMBP2 gene in 53 unrelated Han Chinese non-5q-spinal muscular atrophy patients and 100 healthy controls. Two novel mutations (c.711+1G>C and c.1817G>A) and 5 nucleotide polymorphisms (c.57T>C, c.1554C>T, c.1914G>A, c.2080C>T, and c.2270G>C) were identified. However, only 1 patient harbored the compound heterozygous mutations (c.711+1G>C, c.1817G>A). Furthermore, the homozygous c.2636C>A (p.T879 K) variation, which has been included as a mutation in the Human Gene Mutation Database, was found both in patients and healthy individuals. In conclusion, the IGHMBP2 gene was not found to be a major causative gene linked to Han Chinese non-5q-spinal muscular atrophy patients.
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[Wetland landscape pattern change based on GIS and RS: a review].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 08-01-2013
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Wetland is an ecological landscape with most biodiversity in nature, which has unique ecological structure and function, and contains abundant natural resources to provide material guarantee for humans living and development. Wetland landscape pattern is the comprehensive result of various ecological processes, and has become a hot issue in wetland ecological study. At present, the combination of geographic information system (GIS) and remote sensing (RS) technologies is an important way to study the wetland landscape pattern change. This paper reviewed the research progress in the wetland landscape change based on GIS and RS from the aspects of the research methods of wetland landscape pattern, index of wetland landscape pattern, and driving forces of wetland landscape pattern evolution, and discussed the applications of the combination of GIS and RS in monitoring the wetland landscape pattern change, the index selection of wetland landscape pattern, and the driving mechanisms of the combined action of human and nature. Some deficiencies in the current studies were put forward, and the directions of the future-studies were prospected.
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Total arch repair with open triple-branched stent graft placement for acute type A aortic dissection: Experience with 122 patients.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 07-30-2013
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To summarize the clinical experiences and midterm follow-up results of total arch repair with open triple-branched stent graft placement for acute type A aortic dissection.
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[Clinical research of anterior chamber inflammation after phacoemulsification surgery in patients with complicated cataract secondary to uveitis].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 07-23-2013
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To investigate anterior chamber inflammation after phacoemulsification with intraocular lens (IOL) implantation in patients with Vogt-Koyanagi-Harada (VKH) syndrome or Behçets disease (BD).
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Nasopharyngeal carcinoma incidence and mortality in China in 2009.
Chin J Cancer
PUBLISHED: 07-18-2013
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Nasopharyngeal carcinoma (NPC) is rare globally but common in China and exhibits a distinct ethnic and geographic distribution. In 2009, the National Central Cancer Registry in China provided real-time surveillance information on NPC. Individual NPC cases were retrieved from the national database based on the ICD-10 topography code C11. The crude incidence and mortality of NPC were calculated by sex and location (urban/rural). Chinas population in 1982 and Segis world population structures were used to determine age-standardized rates. In regions covered by the cancer registries in 2009, the crude incidence of NPC was 3.61/100,000 (5.08/100,000 in males and 2.10/100,000 in females; 4.19/100,000 in urban areas and 2.42/100,000 in rural areas). Age-standardized incidences by Chinese population (ASIC) and Segis world population (ASIW) were 2.05/100,000 and 2.54/100,000, respectively. The crude mortality of NPC was 1.99/100,000 (2.82/100,000 in males and 1.14/100,000 in females; 2.30/100,000 in urban areas and 1.37/100,000 in rural areas). The age-standardized mortalities by Chinese population (ASMC) and world population (ASMW) were 1.04/100,000 and 1.35/100,000, respectively. The incidence and mortality of NPC were higher in males than in females and higher in urban areas than in rural areas. Both age-specific incidence and mortality were relatively low in persons younger than 30 years old, but these rates dramatically increased. Incidence peaked in the 60-64 age group and mortality peaked in the over 85 age group. Primary and secondary prevention, such as lifestyle changes and early detection, should be carried out in males and females older than 30 years of age.
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Quick staining technique for myeloperoxidase using potassium iodide and oxidized pyronine B.
Acta Histochem.
PUBLISHED: 06-25-2013
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Myeloperoxidase (MPO) staining has been important for the cytomorphological diagnosis and classification of leukemia. A novel staining method for MPO and its clinical application are presented in the report. Pyronine B (PyB), serving as a chromogenic reagent, was pre-oxidized to obtain stable oxidized Pyronine B solution. The MPO working solution for oxidized pyronine B method consisted of phosphate buffer solution, potassium iodide (KI) solution, and oxidized Pyronine B solution. The positive products of the oxidized Pyronine B method of MPO staining were vibrant red particles located in cytoplasm and the nucleus was stained bluish green. Bone marrow smears from 229 patients with acute leukemia or with grossly normal bone marrow were stained by both oxidized Pyronine B method and the conventional Washburn benzidine staining and a comparison revealed no significant difference in the positive detection rate between the two techniques. The new method eliminates the influence of the varying amount of H2O2 on MPO staining. With this method, the reagents were more stable and the staining procedure was simple and time-saving. This MPO staining technique is a better alternative than the conventional benzidine-based methods.
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[Incidence and mortality of oral and pharyngeal cancers in China, 2003 to 2007].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 06-12-2013
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To analyze the incidence and mortality of oral and pharyngeal cancers from 32 cancer registration centers, 2003 to 2007.
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[Trend and prediction on the incidence of pancreatic cancer in China].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 06-12-2013
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To analyze and predict the incidence trends and burden of pancreatic cancer from 2008 to 2015.
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Identification of differentially expressed genes in American cockroach ovaries and testes by suppression subtractive hybridization and the prediction of its miRNAs.
Mol. Genet. Genomics
PUBLISHED: 04-17-2013
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Studies on the cockroach have contributed to our understanding of several important developmental processes, especially those that can be easily studied in the embryo. However, our knowledge on late events such as gonad differentiation in the cockroach is still limited. The major aim of the present study was to identify sex-specific genes between adult female and male Periplaneta americana. Two cDNA libraries were constructed using the suppression subtractive hybridization method; a total of 433 and 599 unique sequences were obtained from the forward library and the reverse library, respectively, by cluster assembly, and sequence alignment of 1,032 expressed sequence tags. The analysis of the differentially expressed gene functions allowed these genes to be categorized into three groups: biological process, molecular function, and cellular component. The differentially expressed genes were suggested to be related to the development of the gonads of P. americana. Twelve differentially expressed genes were randomly selected and verified using relative quantitative real-time polymerase chain reaction (qRT-PCR). Meanwhile, by adopting a range of filtering criteria, we predicted two potential microRNA sequences for P. americana, pam-miR100-3p and pam-miR7. To confirm the expression of potential microRNAs (miRNAs) in American cockroach, a qRT-PCR approach was also employed. The data presented here offer the insights into the molecular foundation of sex differences in American cockroach, and the first report for the miRNAs in this species. In addition, the results can be used as a reference for unraveling candidate genes associated with the sex and reproduction of cockroaches.
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Oral administration of Lactobacillus reuteri GMNL-263 improves insulin resistance and ameliorates hepatic steatosis in high fructose-fed rats.
Nutr Metab (Lond)
PUBLISHED: 04-14-2013
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Type 2 diabetes mellitus (DM), characterized by peripheral insulin resistance, is the most common form of diabetes. Probiotics are live micro-organisms that, when administered in adequate amounts, confer delaying effect on DM development. In this study, the effects Lactobacillus reuteri GMNL-263 (Lr263), a new probiotic strain developed by our laboratory, on insulin resistance and the development of hepatic steatosis in high-fructose fed rats were explored. Furthermore, the relevant regulatory pathways involved were also investigated.
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Effects of intramolecular hydrogen bonding on the excited state dynamics of phenol chromophores.
Phys Chem Chem Phys
PUBLISHED: 04-06-2013
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The theoretical prediction and experimental confirmation of the 1??* excited state of phenol which is repulsive along the O-H bond has a large impact on the interpretation of phenol and tyrosine photochemistry. In this work, we demonstrate that this excited state changes significantly if the OH functional group is involved in the formation of an intramolecular hydrogen bond in the ground state. We investigate the excited state dynamics of 2-, 3-, and 4-hydroxyacetophenone (HAP) separately in a molecular beam at 193 nm using multimass ion imaging techniques. H atom elimination from the repulsive excited state and Norrish type I reactions are the major dissociation channels of 3-HAP and 4-HAP which do not have intramolecular hydrogen bonding. However, the H atom elimination channel is completely quenched for 2-HAP which shows intramolecular hydrogen bonding. In addition, the ground state and the excited state potential energy surfaces (PESs) of HAP, 2-hydroxybenzoyl fluoride, 2-hydroxybenzoyl chloride, and 2-hydroxybenzamide are investigated using ab initio calculations. The results also show that the excited state potential along the O-H bond distance of the hydroxyl group changes significantly for molecules with intramolecular hydrogen bonding. The changes include: (a) the repulsive potential energy surface becomes an attractive potential near the ground state equilibrium geometry, (b) the conical intersection between the first and the second excited states along the O-H bond moves to a much higher energy level, and (c) the conical intersection between the repulsive excited state and the ground state along the O-H bond distance disappears. The results suggest that the interpretation of the photochemistry for molecules with a phenol chromophore must take these effects into consideration.
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Molecular analysis of the dystrophin gene in 407 Chinese patients with Duchenne/Becker muscular dystrophy by the combination of multiplex ligation-dependent probe amplification and Sanger sequencing.
Clin. Chim. Acta
PUBLISHED: 04-05-2013
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Progressive muscular dystrophy is a leading neuromuscular disorder without any effective treatments and a common genetic cause of mortality among teenagers. A challenge exists in the screening of subtle mutations in 79 exons and little is known about the genotype-phenotype correlation.
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Artocarpin attenuates ultraviolet B-induced skin damage in hairless mice by antioxidant and anti-inflammatory effect.
Food Chem. Toxicol.
PUBLISHED: 04-01-2013
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Artocarpin, a prenylated flavonoid isolated from an agricultural plant Artocarpus communis, has been documented to possess anti-inflammation and anticancer activities. As oxidative stress and inflammation promote the development of ultraviolet B (UVB) irradiation-induced photodamage, the aim of the present study was to evaluate the photoprotective effect of artocarpin on UVB-induced skin damage in hairless mice. Artocarpin at a topical dose of 0.05% and 0.1% showed a significant photoprotective effect by decreasing histopathological changes, such as desquamation, epidermal thicken and sunburn cell formation, but 0.1% of artocarpin administration did not show better effect. Regarding the antioxidant activities, artocarpin exhibited a significant effect (P<0.05) by decreasing levels of reactive species oxygen and lipid peroxidation. In addition, artocarpin can significant decrease the level of tumor necrosis factor-? and interleukin-1? for downregulating the inflammation protein, including the synthesis of cytosolic phospholipase A2 and cyclooxygenase-2 (P<0.05). In conclusion, these data suggest that artocarpin can prevent skin damage from UVB irradiation-induced photodamage in hairless mice and this is likely mediated through its antioxidant and anti-inflammation mechanisms. Therefore, we suggested that artocarpin could be a useful photoprotective agent in medicine and/or cosmetics.
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Reduced WWOX protein expression in human astrocytoma.
Neuropathology
PUBLISHED: 03-26-2013
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The WW domain-containing oxidoreductase (WWOX) functions as a tumor suppressor by interacting with various proteins in numerous important signaling pathways. WWOX silencing via homozygous deletion of its locus and/or promoter hypermethylation has been observed in various human cancers. However, the relationship between WWOX and tumors in the central nervous system has not been fully explored. In this study, the expression levels of WWOX protein in astrocytomas from 38 patients with different tumor grades were retrospectively analyzed by immunohistochemical staining. The results showed that 19 (50.0%) samples had highly reduced WWOX protein expression when compared with normal controls, while 14 (36.8%) and five (13.2%) cases exhibited moderate and mild decreases in WWOX expression, respectively. Reduction of the expression of WWOX protein correlated with patient age, supra-tentorial localization of the tumor and severity of the symptoms. Furthermore, loss of WWOX expression inversely correlated with survival time. No significant correlation was observed between the loss of WWOX expression and the gender of patients or the difference in pre-operative and post-operative karnofsky performance status scores. Surprisingly, there was no significant correlation between the loss of WWOX protein expression and overall tumor grades. Nevertheless, it was found that 63.6% (7/11) of the grade II astrocytomas had highly reduced WWOX expression and 36.4% (4/11) showed moderately reduced WWOX expression, while none of the samples exhibited mild reductions. Similar results were also found in grade III astrocytomas. The results from this small-size sample pilot study suggest that the loss of WWOX expression may be an early event in the pathogenesis of human astrocytoma.
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Valve-sparing root replacement with root reduction plasty and patch neointima placement.
Ann. Thorac. Surg.
PUBLISHED: 03-26-2013
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We describe an alternative valve-sparing aortic root replacement technique for patients with root aneurysms accompanied by aortic valve insufficiency. Aortic root reduction plasty was accomplished by plication and exclusion of parts of the sinus walls. Subsequently, 3 teardrop-shaped patches compatible with the sizes and shapes of the corresponding plicated sinuses were sutured inside the sinuses as neointima, and in situ coronary buttons were connected to the small holes created in the corresponding patches. A Dacron tube graft was then anastomosed to the reconstructed aortic root with incorporation of the distal margin of the implanted patches. Our initial application showed that this combined root reduction plasty and patch neointima placement is a feasible valve-sparing aortic root replacement technique. This combined technique easily restores the aortic root geometry and effectively prevents bleeding.
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Effect of Thermal Annealing on the Surface Properties of Electrospun Polymer Fibers.
Macromol Rapid Commun
PUBLISHED: 03-25-2013
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Electrospun polymer fibers are gaining importance because of their unique properties and applications in areas such as drug delivery, catalysis, or tissue engineering. Most studies to control the morphology and properties of electrospun polymer fibers focus on changing the electrospinning conditions. The effects of post-treatment processes on the morphology and properties of electrospun polymer fibers, however, are little studied. Here, the effect of thermal annealing on the surface properties of electrospun polymer fibers is investigated. Poly(methyl methacrylate) and polystyrene fibers are fist prepared by electrospinning, followed by thermal annealing processes. Upon thermal annealing, the surface roughness of the electrospun polymer fibers decreases. The driving force of the smoothing process is the minimization of the interfacial energy between polymer fibers and air. The water contact angles of the annealed polymer fibers also decrease with the annealing time.
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Liver cancer incidence and mortality in China, 2009.
Chin J Cancer
PUBLISHED: 03-15-2013
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Liver cancer is a common cancer and a leading cause of cancer deaths in China. To aid the government in establishing a control plan for this disease, we provided real-time surveillance information by analyzing liver cancer incidence and mortality in China in 2009 reported by the National Central Cancer Registry. Liver cancer incidence and cases of death were retrieved from the national database using the ICD-10 topography code "C22". Crude incidence and mortality were calculated and stratified by sex, age, and location (urban/rural). Chinas population in 1982 and Segi (world) population structures were used for age-standardized rates. In cancer registration areas in 2009, the crude incidence of liver cancer was 28.71/100,000, making it the fourth most common cancer in China, third most common in males, and fifth most common in females. The crude mortality of liver cancer was 26.04/100,000, making it the second leading cause of cancer death in China and urban areas and the third leading cause in rural areas. Incidence and mortality were higher in males than in females and were higher in rural areas than in urban areas. The age-specific incidence and mortality were relatively low among age groups under 30 years but dramatically increased and peaked in the 80-84 years old group. These findings confirm that liver cancer is a common and fatal cancer in China. Primary and secondary prevention such as health education, hepatitis B virus vaccination, and early detection should be carried out both in males and females, in urban and rural areas.
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Theoretical analysis on the kinetic isotope effects of bimolecular nucleophilic substitution (S(N)2) reactions and their temperature dependence.
Molecules
PUBLISHED: 03-13-2013
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Factors affecting the kinetic isotope effects (KIEs) of the gas-phase S(N)2 reactions and their temperature dependence have been analyzed using the ion-molecule collision theory and the transition state theory (TST). The quantum-mechanical tunneling effects were also considered using the canonical variational theory with small curvature tunneling (CVT/SCT). We have benchmarked a few ab initio and density functional theory (DFT) methods for their performance in predicting the deuterium KIEs against eleven experimental values. The results showed that the MP2/aug-cc-pVDZ method gave the most accurate prediction overall. The slight inverse deuterium KIEs usually observed for the gas-phase S(N)2 reactions at room temperature were due to the balance of the normal rotational contribution and the significant inverse vibrational contribution. Since the vibrational contribution is a sensitive function of temperature while the rotation contribution is temperature independent, the KIEs are thus also temperature dependent. For S(N)2 reactions with appreciable barrier heights, the tunneling effects were predicted to contribute significantly both to the rate constants and to the carbon-13, and carbon-14 KIEs, which suggested important carbon atom tunneling at and below room temperature.
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