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Find video protocols related to scientific articles indexed in Pubmed.
Factor Structure of the Screen for Child Anxiety-Related Emotional Disorders (SCARED) in a Community Sample of Hong Kong Chinese Adolescents.
Child Psychiatry Hum Dev
PUBLISHED: 10-08-2014
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The current study tested the factor structure of the 41-item SCARED in assessing anxiety in a sample of Hong Kong adolescents. Data were collected from 5,226 youths (54.5 % boys) aged 12-18. Results showed that the scale and the five subscales had high internal consistency. However, confirmatory factor analyses showed that the original five-factor model did not fit the data collected in this sample. Instead, the results revealed a seven-factor model consisting of one second-order factor of anxiety and seven first-order factors: the four original factors of General Anxiety, Panic/Somatic Syndromes, Social Anxiety, and School Phobia and three new factors representing different aspects of Separation Anxiety. Group invariance in the Boys and Girls models was found. It is recommended that the three new factors (Fear of Loneliness, Separation Fear, Worry about Harm) be further developed by adding new items so as to enhance the content and construct validities of the SCARED when used with Hong Kong adolescents.
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Secondhand smoke exposure and maternal action to protect children from secondhand smoke: pre- and post-smokefree legislation in Hong Kong.
PLoS ONE
PUBLISHED: 08-28-2014
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Smokefree legislation may protect children from secondhand smoke (SHS) in the home from smoking parent(s). We examined the effect of the 2007 smokefree legislation on children's exposure to SHS in the home and maternal action to protect children from SHS exposure in Hong Kong.
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A retrospective review of the prognostic value of ALDH-1, Bmi-1 and Nanog stem cell markers in esophageal squamous cell carcinoma.
PLoS ONE
PUBLISHED: 08-22-2014
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Stem cell markers are upregulated in various cancers and have potential as prognostic indicators. The objective of this study was to determine the expression of three stem cell markers, aldehyde dehydrogenase 1 (ALDH-1), B cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1), and Nanog, in esophageal squamous cell carcinoma (ESCC) tissues. Immunohistochemistry was used to measure the expression of ALDH-1, Bmi-1, and Nanog in ESCC tissues from 41 patients who received pre-operative chemoradiation. We evaluated the relationship between expression of these markers, and clinicopathological features, tumor regression grade (TRG), and 5-year overall survival (OS). There were no significant associations of ALDH-1 or Bmi-1 expression with age, gender, clinical stage, and treatments (p>0.05). However, patients with Nanog-positive tumors were significantly older than those whose tumors were Nanog-negative (p?=?0.033). TRG after treatment was significantly associated with expression of ALDH-1 (p?=?0.001), Bmi-1 (p?=?0.004), and Nanog (p<0.001). Although OS was significantly better in patients with low TRGs (p?=?0.001), there were no significant correlations between ALDH-1, Bmi-1, or Nanog with OS. Expression of ALDH-1, Bmi-1, and Nanog correlated with TRG, but not OS. Further large studies are necessary to fully elucidate the prognostic value of these stem cell markers for ESCC patients.
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Reply to the letter to the editor: A rare case of breast cancer showing distinct TTF-1 nuclear expression: small cell carcinoma or not?
Histopathology
PUBLISHED: 08-11-2014
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Thank you for the opportunity to respond to the letter regarding our recently published article on TTF-1 expression in breast cancer (1). We very much appreciate Kawasaki T et al for sharing their experience and opinion on the immunoreactivity of TTF-1 in small cell carcinoma of the breast in the accompanied correspondence (2). TTF-1 expression has been reported in a few cases of small cell carcinoma of the breast (3). This article is protected by copyright. All rights reserved.
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Estimating biological elementary flux modes that decompose a flux distribution by the minimal branching property.
Bioinformatics
PUBLISHED: 08-06-2014
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Elementary flux mode (EFM) is a useful tool in constraint-based modeling of metabolic networks. The property that every flux distribution can be decomposed as a weighted sum of EFMs allows certain applications of EFMs to studying flux distributions. The existence of biologically infeasible EFMs and the non-uniqueness of the decomposition, however, undermine the applicability of such methods. Efforts have been made to find biologically feasible EFMs by incorporating information from transcriptional regulation and thermodynamics. Yet, no attempt has been made to distinguish biologically feasible EFMs by considering their graphical properties. A previous study on the transcriptional regulation of metabolic genes found that distinct branches at a branch point metabolite usually belong to distinct metabolic pathways. This suggests an intuitive property of biologically feasible EFMs, i.e. minimal branching.
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Postischemic reperfusion causes smooth muscle calcium sensitization and vasoconstriction of parenchymal arterioles.
Stroke
PUBLISHED: 06-26-2014
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Parenchymal arterioles (PAs) are high-resistance vessels in the brain that connect pial vessels to the microcirculation. We previously showed that PAs have increased vasoconstriction after ischemia and reperfusion that could increase perfusion deficit. Here, we investigated underlying mechanisms by which early postischemic reperfusion causes increased vasoconstriction of PAs.
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Constitutive activity of the androgen receptor.
Adv. Pharmacol.
PUBLISHED: 06-17-2014
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Prostate cancer (PCa) is the most frequently diagnosed cancer in the United States. The androgen receptor (AR) signaling axis is central to all stages of PCa pathophysiology and serves as the main target for endocrine-based therapy. The most advanced stage of the disease, castration-resistant prostate cancer (CRPC), is presently incurable and accounts for most PCa mortality. In this chapter, we highlight the mechanisms by which the AR signaling axis can bypass endocrine-targeted therapies and drive progression of CRPC. These mechanisms include alterations in growth factor, cytokine, and inflammatory signaling pathways, altered expression or activity of transcriptional coregulators, AR point mutations, and AR gene amplification leading to AR protein overexpression. Additionally, we will discuss the mechanisms underlying the synthesis of constitutively active AR splice variants (AR-Vs) lacking the COOH-terminal ligand-binding domain, as well as the role and regulation of AR-Vs in supporting therapeutic resistance in CRPC. Finally, we summarize the ongoing development of inhibitors targeting discrete AR functional domains as well as the status of new biomarkers for monitoring the AR signaling axis in patients.
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Increased pressure-induced tone in rat parenchymal arterioles vs. middle cerebral arteries: role of ion channels and calcium sensitivity.
J. Appl. Physiol.
PUBLISHED: 05-01-2014
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Brain parenchymal arterioles (PAs) are high-resistance vessels that branch off pial arteries and perfuse the brain parenchyma. PAs are the target of cerebral small vessel disease and have been shown to have greater pressure-induced tone at lower pressures than pial arteries. We investigated mechanisms by which brain PAs have increased myogenic tone compared with middle cerebral arteries (MCAs), focusing on differences in vascular smooth muscle (VSM) calcium and ion channel function. The amount of myogenic tone and VSM calcium was measured using Fura 2 in isolated and pressurized PAs and MCAs. Increases in intraluminal pressure caused larger increases in tone and cytosolic calcium in PAs compared with MCAs. At 50 mmHg, myogenic tone was 37 ± 5% for PAs vs. 6.5 ± 4% for MCAs (P < 0.01), and VSM calcium was 200 ± 20 nmol/l in PAs vs. 104 ± 15 nmol/l in MCAs (P < 0.01). In vessels permeabilized with Staphylococcus aureus ?-toxin, PAs were not more sensitive to calcium, suggesting calcium sensitization was not at the level of the contractile apparatus. PAs were 30-fold more sensitive to the voltage-dependent calcium channel (VDCC) inhibitor nifedipine than MCAs (EC50 for PAs was 3.5 ± 0.4 vs. 82.1 ± 2.1 nmol/l for MCAs;P < 0.01); however, electrophysiological properties of the VDCC were not different in VSM. PAs had little to no response to the calcium-activated potassium channel inhibitor iberiotoxin, whereas MCAs constricted ?15%. Thus increased myogenic tone in PAs appears related to differences in ion channel activity that promotes VSM membrane depolarization but not to a direct sensitization of the contractile apparatus to calcium.
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Structure of archaerhodopsin-2 at 1.8?Å resolution.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 04-18-2014
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Archaerhodopsin-2 (aR2), the sole protein found in the claret membrane of Halorubrum sp. Aus-2, functions as a light-driven proton pump. In this study, structural analysis of aR2 was performed using a novel three-dimensional crystal prepared by the successive fusion of claret membranes. The crystal is made up of stacked membranes, in each of which aR2 trimers are arranged on a hexagonal lattice. This lattice structure resembles that found in the purple membrane of H. salinarum, except that lipid molecules trapped within the trimeric structure are not distributed with perfect threefold symmetry. Nonetheless, diffraction data at 1.8?Å resolution provide accurate structural information about functionally important residues. It is shown that two glutamates in the proton-release channel form a paired structure that is maintained by a low-barrier hydrogen bond. Although the structure of the proton-release pathway is highly conserved among proton-pumping archaeal rhodopsins, aR2 possesses the following peculiar structural features: (i) the motional freedom of the tryptophan residue that makes contact with the C13 methyl group of retinal is restricted, affecting the formation/decay kinetics of the L state, and (ii) the N-terminal polypeptide folds into an ?-loop, which may play a role in organizing the higher-order structure.
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A novel morphologic-molecular recurrence predictive model refines traditional prognostic tools for invasive breast carcinoma.
Ann. Surg. Oncol.
PUBLISHED: 04-18-2014
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Histologic grade, TNM stage, and Nottingham Prognostic Index are traditional prognostic tools for breast cancer. "IHC-molecular" classification of breast cancer can also identify patients at different recurrence risks and provides insight into cancer therapy. However, cancers in each group are heterogeneous. A model based on the comprehensive analysis of morphologic features and molecular subtype was constructed to predict recurrence and refine these traditional prognostic tools.
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Androgen receptor expression shows distinctive significance in ER positive and negative breast cancers.
Ann. Surg. Oncol.
PUBLISHED: 03-18-2014
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Androgen receptor (AR), a nuclear steroid hormone receptor, is differentially expressed in breast cancer subgroups with distinct clinical implications.
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Ruminative and Catastrophizing Cognitive Styles Mediate the Association Between Daily Hassles and High Anxiety in Hong Kong Adolescents.
Child Psychiatry Hum Dev
PUBLISHED: 02-27-2014
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This study assessed rumination, catastrophizing and daily hassles as predictors of anxiety when controlling for depressive symptoms in a community sample of adolescents reporting high anxiety. Adolescents aged 12-18 (N = 2,802, mean age of 14.9) completed the Screen For Child Anxiety-Related Emotional Disorders. With a total score of 30 as the cutoff, a group of high anxiety adolescents was identified (a prevalence rate of 28.02 %). Path analyses results showed that amongst the high anxiety boys, catastrophizing but not rumination was a positive predictor of anxiety and it mediated the effects of daily hassles on anxiety. In the high anxiety girls, both rumination and catastrophizing predicted anxiety but only catastrophizing was the mediator between daily hassles and anxiety. It is suggested that such gender differences in cognitive responses styles should be considered in cognitive-behavioral therapeutic approaches designed to help adolescents showing high anxiety.
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A correlation study between in-brace correction, compliance to spinal orthosis and health-related quality of life of patients with Adolescent Idiopathic Scoliosis.
Scoliosis
PUBLISHED: 01-28-2014
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It has been proposed that in-brace correction is the best guideline for prediction of the results of brace treatment for patients with Adolescent Idiopathic Scoliosis (AIS). However, bracing may be a stressful experience for patients and bracing non-compliance could be psychologically related. The purpose of this study was to assess the correlation between brace compliance, in-brace correction and QoL of patients with AIS.
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The nucleosome assembly protein TSPYL2 regulates the expression of NMDA receptor subunits GluN2A and GluN2B.
Sci Rep
PUBLISHED: 01-14-2014
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TSPYL2 is an X-linked gene encoding a nucleosome assembly protein. TSPYL2 interacts with calmodulin-associated serine/threonine kinase, which is implicated in X-linked mental retardation. As nucleosome assembly and chromatin remodeling are important in transcriptional regulation and neuronal function, we addressed the importance of TSPYL2 through analyzing Tspyl2 loss-of-function mice. We detected down-regulation of N-methyl-D-aspartate receptor subunits 2A and 2B (GluN2A and GluN2B) in the mutant hippocampus. Evidence from luciferase reporter assays and chromatin immunoprecipitation supported that TSPYL2 regulated the expression of Grin2a and Grin2b, the genes encoding GluN2A and GluN2B. We also detected an interaction between TSPYL2 and CBP, indicating that TSPYL2 may activate gene expression through binding CBP. In terms of functional outcome, Tspyl2 loss-of-function impaired long-term potentiation at hippocampal Schaffer collateral-CA1 synapses. Moreover, mutant mice showed a deficit in fear learning and memory. We conclude that TSPYL2 contributes to cognitive variability through regulating the expression of Grin2a and Grin2b.
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Elimination of inter-domain interactions increases the cleavage fidelity of the restriction endonuclease DraIII.
Protein Cell
PUBLISHED: 01-05-2014
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DraIII is a type IIP restriction endonucleases (REases) that recognizes and creates a double strand break within the gapped palindromic sequence CAC?NNN?GTG of double-stranded DNA (? indicates nicking on the bottom strand; ? indicates nicking on the top strand). However, wild type DraIII shows significant star activity. In this study, it was found that the prominent star site is CAT?GTT?GTG, consisting of a star 5' half (CAT) and a canonical 3' half (GTG). DraIII nicks the 3' canonical half site at a faster rate than the 5' star half site, in contrast to the similar rate with the canonical full site. The crystal structure of the DraIII protein was solved. It indicated, as supported by mutagenesis, that DraIII possesses a ???-metal HNH active site. The structure revealed extensive intra-molecular interactions between the N-terminal domain and the C-terminal domain containing the HNH active site. Disruptions of these interactions through site-directed mutagenesis drastically increased cleavage fidelity. The understanding of fidelity mechanisms will enable generation of high fidelity REases.
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Magnesium Sulfate Treatment Reverses Seizure Susceptibility and Decreases Neuroinflammation in a Rat Model of Severe Preeclampsia.
PLoS ONE
PUBLISHED: 01-01-2014
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Eclampsia, defined as unexplained seizure in a woman with preeclampsia, is a life-threatening complication of pregnancy with unclear etiology. Magnesium sulfate (MgSO4) is the leading eclamptic seizure prophylactic, yet its mechanism of action remains unclear. Here, we hypothesized severe preeclampsia is a state of increased seizure susceptibility due to blood-brain barrier (BBB) disruption and neuroinflammation that lowers seizure threshold. Further, MgSO4 decreases seizure susceptibility by protecting the BBB and preventing neuroinflammation. To model severe preeclampsia, placental ischemia (reduced uteroplacental perfusion pressure; RUPP) was combined with a high cholesterol diet (HC) to cause maternal endothelial dysfunction. RUPP+HC rats developed symptoms associated with severe preeclampsia, including hypertension, oxidative stress, endothelial dysfunction and fetal and placental growth restriction. Seizure threshold was determined by quantifying the amount of pentylenetetrazole (PTZ; mg/kg) required to elicit seizure in RUPP+HC±MgSO4 and compared to normal pregnant controls (n?=?6/group; gestational day 20). RUPP+HC rats were more sensitive to PTZ with seizure threshold being ?65% lower vs. control (12.4±1.7 vs. 36.7±3.9 mg/kg PTZ; p<0.05) that was reversed by MgSO4 (45.7±8.7 mg/kg PTZ; p<0.05 vs. RUPP+HC). BBB permeability to sodium fluorescein, measured in-vivo (n?=?5-7/group), was increased in RUPP+HC vs. control rats, with more tracer passing into the brain (15.9±1.0 vs. 12.2±0.3 counts/gram ×1000; p<0.05) and was unaffected by MgSO4 (15.6±1.0 counts/gram ×1000; p<0.05 vs. controls). In addition, RUPP+HC rats were in a state of neuroinflammation, indicated by 35±2% of microglia being active compared to 9±2% in normal pregnancy (p<0.01; n?=?3-8/group). MgSO4 treatment reversed neuroinflammation, reducing microglial activation to 6±2% (p<0.01 vs. RUPP+HC). Overall, RUPP+HC rats were in a state of augmented seizure susceptibility potentially due to increased BBB permeability and neuroinflammation. MgSO4 treatment reversed this, increasing seizure threshold and decreasing neuroinflammation, without affecting BBB permeability. Thus, reducing neuroinflammation may be one mechanism by which MgSO4 prevents eclampsia during severe preeclampsia.
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Crystal structure of Cruxrhodopsin-3 from Haloarcula vallismortis.
PLoS ONE
PUBLISHED: 01-01-2014
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Cruxrhodopsin-3 (cR3), a retinylidene protein found in the claret membrane of Haloarcula vallismortis, functions as a light-driven proton pump. In this study, the membrane fusion method was applied to crystallize cR3 into a crystal belonging to space group P321. Diffraction data at 2.1 Å resolution show that cR3 forms a trimeric assembly with bacterioruberin bound to the crevice between neighboring subunits. Although the structure of the proton-release pathway is conserved among proton-pumping archaeal rhodopsins, cR3 possesses the following peculiar structural features: 1) The DE loop is long enough to interact with a neighboring subunit, strengthening the trimeric assembly; 2) Three positive charges are distributed at the cytoplasmic end of helix F, affecting the higher order structure of cR3; 3) The cytoplasmic vicinity of retinal is more rigid in cR3 than in bacteriorhodopsin, affecting the early reaction step in the proton-pumping cycle; 4) the cytoplasmic part of helix E is greatly bent, influencing the proton uptake process. Meanwhile, it was observed that the photobleaching of retinal, which scarcely occurred in the membrane state, became significant when the trimeric assembly of cR3 was dissociated into monomers in the presence of an excess amount of detergent. On the basis of these observations, we discuss structural factors affecting the photostabilities of ion-pumping rhodopsins.
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Use of Internet viral marketing to promote smoke-free lifestyles among Chinese adolescents.
PLoS ONE
PUBLISHED: 01-01-2014
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Youth smoking is a global public health concern. Health educators are increasingly using Internet-based technologies, but the effectiveness of Internet viral marketing in promoting health remains uncertain. This prospective pilot study assessed the efficacy of an online game-based viral marketing campaign in promoting a smoke-free attitude among Chinese adolescents.
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Acetate kinase isozymes confer robustness in acetate metabolism.
PLoS ONE
PUBLISHED: 01-01-2014
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Acetate kinase (ACK) (EC no: 2.7.2.1) interconverts acetyl-phosphate and acetate to either catabolize or synthesize acetyl-CoA dependent on the metabolic requirement. Among all ACK entries available in UniProt, we found that around 45% are multiple ACKs in some organisms including more than 300 species but surprisingly, little work has been done to clarify whether this has any significance. In an attempt to gain further insight we have studied the two ACKs (AckA1, AckA2) encoded by two neighboring genes conserved in Lactococcus lactis (L. lactis) by analyzing protein sequences, characterizing transcription structure, determining enzyme characteristics and effect on growth physiology. The results show that the two ACKs are most likely individually transcribed. AckA1 has a much higher turnover number and AckA2 has a much higher affinity for acetate in vitro. Consistently, growth experiments of mutant strains reveal that AckA1 has a higher capacity for acetate production which allows faster growth in an environment with high acetate concentration. Meanwhile, AckA2 is important for fast acetate-dependent growth at low concentration of acetate. The results demonstrate that the two ACKs have complementary physiological roles in L. lactis to maintain a robust acetate metabolism for fast growth at different extracellular acetate concentrations. The existence of ACK isozymes may reflect a common evolutionary strategy in bacteria in an environment with varying concentrations of acetate.
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Lymphocytic infiltrate is associated with favorable biomarkers profile in HER2-overexpressing breast cancers and adverse biomarker profile in ER-positive breast cancers.
Breast Cancer Res. Treat.
PUBLISHED: 10-15-2013
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The value for lymphocytic infiltration (LI) has been increasingly recognized for tumor assessment. In breast cancer, however, the overall significance of LI remains poorly defined, probably due to its heterogeneity. A large cohort of breast cancer was evaluated for the degree of LI and its association with traditional pathologic factors, biomarker expression, and cancer subtypes. The number of CD8 cytotoxic effector and FoxP3 regulatory T cell (Treg) was evaluated in those cases with high LI. High LI was associated with negative ER and PR but positive HER2 and EGFR expression (p < 0.001 for all). In ER-positive cancers, high LI was associated with poor prognostic features including higher grade, the presence of necrosis, and lymphovascular invasion (LVI) (p = 0.007 for LVI and <0.001 for the others). Conversely, LI correlated with smaller tumor size, a good prognostic feature (p = 0.046) in HER2+ ER-cancers. These observations suggested LI may show opposite prognostic values in different breast cancer subgroups. Interestingly, when the phenotype of LI in these subgroups was evaluated, a strong positive association with intratumoral accumulation of Treg was found in ER-positive cancers (p = 0.003, Rs = 0.319), while the opposite was observed in HER2+ ER-cancers (p < 0.001, Rs = -0.427). Also, in ER-positive cancers, positive associations between peri- and intra-tumoral distribution were found with both CD8 and Tregs (CD8: p < 0.001, Rs = 0.547; Treg: p = 0.001, Rs = 0.460). Nonetheless, in HER2+ ER-cancers, such strong association was found with CD8 (p < 0.001, Rs = 0.766) but not Tregs. The results may implicate a differential intratumoral migration of LI in different subtypes of breast cancer. In summary, the clinical value of LI in breast cancers could be subtype-dependent. In ER-positive cancers, high LI correlated with biologic parameters associated with poor prognosis, whereas in HER2 positive cancers, LI correlated with biologic parameters of favorable prognosis.
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Development and validation of the Chinese Health Literacy Scale for Chronic Care.
J Health Commun
PUBLISHED: 10-08-2013
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This study aims to develop and test the psychometric properties of the Chinese Health Literacy Scale for Chronic Care (CHLCC). This is a methodological study with a sample of 262 patients 65 years of age and older who had chronic illnesses. Pearsons correlation, independent sample t tests, and analyses of variance were used. The CHLCC showed a significant positive correlation with Chinese literacy levels (r = 0.80; p < .001) but was negatively correlated with age (r =-0.31; p <.001). Respondents who were male (t =4.34; p <.001) and who had reached Grade 12 or higher in school (F = 51.80; p <.001) had higher CHLCC scores than did their counterparts. Individuals with high levels of health literacy had fewer hospitalizations than did their counterparts (? =-0.31; incidence rate ratio = 0.73; p <.05). The CHLCC also displayed good internal reliability (Cronbachs? =0.91) and good test-retest reliability (intraclass correlation coefficient = 0.77; p <.01). The CHLCC is a valid and reliable measure for assessing health literacy among Chinese patients with chronic illness. The scale could be used by practitioners before implementing health promotion and education.
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Expression and clinical significance of carcinoembryonic antigen-related cell adhesion molecule 6 in breast cancers.
Breast Cancer Res. Treat.
PUBLISHED: 09-17-2013
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Carcino-embryonic antigen-related cell adhesion molecule 6 (CEACAM6), one of the members of human carcino-embryonic antigens, is a multifunctional regulatory protein involved in various cellular processes in cancers. Its role in malignant transformation and the clinical significance has been extensively studied in colonic and pancreatic cancers. However, relatively few studies have been done on breast cancers. In the current study, CEACAM6 expression in two independent cohorts of invasive breast cancers were evaluated immunohistochemically and correlated with clinico-pathological features, biomarker profiles and patient survival. In the primary cohort, CEACAM6 expression was detected in 37.1 % (312/840) of primary invasive cancers. It was positively correlated with HER2 (p < 0.001). Concordantly, HER2-OE subtype showed the highest CEACAM6 expression (62.7 %) among all molecular subtypes; whereas, other subtypes also showed substantial CEACAM6 expression (21.8-37.5 %). Interestingly, a significantly worse overall survival was found in high pN stage HER2 positive cancers with CEACAM6 positivity (log-rank = 4.452, p = 0.035) and this could be validated in an independent cohort. Additionally, HER2 signaling was found to induce SMAD3 phosphorylation and CEACAM6 expression in a cell line model. Likewise, in the primary tumors, a positive association was found between HER2 and SMAD3 phosphorylation in CEACAM6 positive cancers (p = 0.012). Overall, CEACAM6 was widely expressed in different molecular subtypes, but highest and significantly in HER2-OE breast cancer. Within this group, CEACAM6 was associated with adverse high nodal stage patient outcome. Given the wide expression of CEACAM6 in all breast cancers, its roles as prognostic marker and therapeutic target warrant further evaluation.
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cDNA cloning and mRNA expression of retinoid-X-receptor in the ovary of the shrimp Metapenaeus ensis.
Mol. Biol. Rep.
PUBLISHED: 09-14-2013
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Retinoid-X-receptor (RXR) plays an essential role in the molting process of decapod crustaceans, by forming a heterodimeric complex with the ecdysteroid receptor. However, its role during female reproduction, especially in the process of ovarian maturation, has not been characterized. To get an insight into the molecular events governing the process of ovarian maturation in shrimps, the full-length cDNA of RXR from Metapenaeus ensis was cloned by extension of truncated cDNA by using the RACE technique. The open reading frame of MeRXR encodes a 410 amino acid protein with a deduced molecular weight of 44.8 kDa, and putative pI of 6.64, which roughly matched our observation from 2DE gel. Phylogenetic analysis showed that MeRXR has high similarity to RXR of Penaeus chinensis and P. japonicus. RT-PCR revealed that MeRXR was universally expressed in all tissues investigated. The variation in MeRXR mRNA expression pattern during ovarian maturation was further analyzed by real-time PCR. In contrast to the decrease in MeRXR at protein level with ovarian maturation, MeRXR mRNA level was low in pre-vitellogenic and mid-vitellogenic ovaries, and increased significantly from mid-vitellogenic to late-vitellogenic stages. This result suggests that MeRXR transcripts in the mature ovary probably act as maternal messages for regulating early molting events during embryonic development.
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Increasing cleavage specificity and activity of restriction endonuclease KpnI.
Nucleic Acids Res.
PUBLISHED: 08-19-2013
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Restriction enzyme KpnI is a HNH superfamily endonuclease requiring divalent metal ions for DNA cleavage but not for binding. The active site of KpnI can accommodate metal ions of different atomic radii for DNA cleavage. Although Mg(2+) ion higher than 500 ?M mediates promiscuous activity, Ca(2+) suppresses the promiscuity and induces high cleavage fidelity. Here, we report that a conservative mutation of the metal-coordinating residue D148 to Glu results in the elimination of the Ca(2+)-mediated cleavage but imparting high cleavage fidelity with Mg(2+). High cleavage fidelity of the mutant D148E is achieved through better discrimination of the target site at the binding and cleavage steps. Biochemical experiments and molecular dynamics simulations suggest that the mutation inhibits Ca(2+)-mediated cleavage activity by altering the geometry of the Ca(2+)-bound HNH active site. Although the D148E mutant reduces the specific activity of the enzyme, we identified a suppressor mutation that increases the turnover rate to restore the specific activity of the high fidelity mutant to the wild-type level. Our results show that active site plasticity in coordinating different metal ions is related to KpnI promiscuous activity, and tinkering the metal ion coordination is a plausible way to reduce promiscuous activity of metalloenzymes.
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Ruthenium(II) and osmium(II) complexes bearing bipyridine and the N-heterocyclic carbene-based C^N^C pincer ligand: an experimental and density functional theory study.
Inorg Chem
PUBLISHED: 08-16-2013
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Ruthenium(II) and osmium(II) complexes [M(C^N^C)(N^N)L](n+) (L = Cl(-), n = 1; L = CH3CN, t-BuNC, n = 2) containing a neutral tridentate N-heterocyclic carbene (NHC)-based pincer ligand, either 2,6-bis(1-butylimidazol-2-ylidene)pyridine (C(1)^N^C(1)) or 2,6-bis(3-butylbenzimidazol-2-ylidene)pyridine (C(2)^N^C(2)), and a neutral 2,2-bipyridine-type aromatic diimine have been prepared. Investigations into the effects of varying M (Ru and Os), C^N^C, N^N, and L on the structural, electrochemical, absorption, and emission characteristics associated with [M(C^N^C)(N^N)L](n+) are presented. Interestingly, spectroscopic findings and time-dependent density functional theory (TD-DFT) calculations in this work support a d?(Ru(II)/Os(II)) ? ?*(N^N) metal-to-ligand charge transfer (MLCT) assignment for the lowest-energy transition in [M(C^N^C)(N^N)L](n+) and not a d?(Ru(II)/Os(II)) ? ?*(C^N^C) MLCT assignment. This is in stark contrast to [Ru(tpy)(bpy)Cl](+) and [Os(tpy)(bpy)Cl](+) (tpy = 2,2:6,2?-terpyridine, bpy = 2,2-bipyridine) for which the lowest-energy transitions are assigned as d?(Ru/Os) ? ?*(tpy) MLCT transitions. [Ru(II)(C^N^C)(N^N)L](n+) is emissive with emission maxima of around 600-700 nm observed upon photoexcitation of their d?(Ru(II)) ? ?*(N^N) MLCT bands. The electronic structures for [Ru(C^N^C)(N^N)Cl](0) have also been probed by spectroelectrochemistry, electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations, which reveal that the lowest unoccupied molecular orbitals (LUMOs) for [Ru(C^N^C)(N^N)Cl](+) are N^N-based.
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Columnar cell-like changes in the male breast.
J. Clin. Pathol.
PUBLISHED: 08-06-2013
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Columnar cell lesions are known as a link between normal breast and low grade neoplastic lesions in female, but have not been established in the male breast. This study evaluated the presence of ducts showing columnar cell-like features in the male breast.
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TTF-1 expression in breast carcinoma: an unusual but real phenomenon.
Histopathology
PUBLISHED: 08-05-2013
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To evaluate thyroid transcription factor-1 (TTF-1) expression in a large cohort of invasive breast carcinomas (IBCs) using two commercially available monoclonal antibody clones (8G7G3/1 and SPT24).
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Human placenta as an ex vivo vascular model for neurointerventional research.
J Neurointerv Surg
PUBLISHED: 07-31-2013
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Human placenta is a convenient resource for biomedical research, and has not yet been used for neurointerventional surgery research.
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Influence of different positions on hemodynamics derived from noninvasive transcutaneous Doppler ultrasound.
Physiol Rep
PUBLISHED: 07-11-2013
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A proper alignment of the ultrasound beam to the aortic or pulmonary outflow tracts is essential to acquire accurate signals. This study aimed to investigate the influence of different positions on the acquisition of Doppler signals using a noninvasive transcutaneous Doppler ultrasound. This was a prospective observational crossover study. Two operators performed hemodynamics measurements on each subject in supine, sitting, semirecumbent, passive leg raising (PLR) 20°, and PLR 60° positions using both aortic and pulmonary approaches. All Doppler flow profile images were assessed using the Fremantle and Prince of Wales Hospital criteria. Time required to obtain Doppler signals was recorded. A total of 60 subjects (50% males) aged 18-60 years old were investigated. In both sitting and semirecumbent positions, aortic stroke volume indexes (SVIs) and cardiac indexes (CIs) were significantly lower than those in the other three positions while the pulmonary CIs were comparable to that in the supine position. In the sitting position, the aortic signal qualities were lower and the time to obtain the pulmonary Doppler signals was prolonged. Instead, the signal quality and the time to obtain the Doppler signals in the semirecumbent position were similar to those in the other three positions using the pulmonary approach. PLR did not cause a significant increase in SVI regardless of the degree of leg elevation. These data show that it is feasible to perform the noninvasive transcutaneous Doppler ultrasound using the pulmonary approach in the semirecumbent position for patients unable to maintain the supine position. The aortic approach in the sitting and semirecumbent positions is not suitable as it is not sufficiently reliable.
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Treatment for cerebral small vessel disease: effect of relaxin on the function and structure of cerebral parenchymal arterioles during hypertension.
FASEB J.
PUBLISHED: 06-19-2013
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We investigated the effect of hypertension on the function and structure of cerebral parenchymal arterioles (PAs), a major target of cerebral small vessel disease (SVD), and determined whether relaxin is a treatment for SVD during hypertension. PAs were isolated from 18-wk-old female normotensive Wistar-Kyoto (WKY) rats, spontaneous hypertensive rats (SHRs), and SHRs treated with human relaxin 2 for 14 d (4 ?g/h; n=8/group) and studied using a pressurized arteriograph system. Hypertension reduced PA inner diameter (58±3 vs. 49±3 ?m at 60 mmHg in WKY rats, P<0.05), suggesting inward remodeling that was reversed by relaxin (56±4 ?m, P<0.05). Relaxin also increased PA distensibility in SHRs (34±2 vs. 10±2% in SHRs, P<0.05). Relaxin was detected in cerebrospinal fluid (110±30 pg/ml) after systemic administration, suggesting that it crosses the blood-brain barrier (BBB). Relaxin receptors (RXFP1/2) were not detected in cerebral vasculature, but relaxin increased vascular endothelial growth factor (VEGF) and matrix metalloproteinase 2 (MMP-2) expression in brain cortex. Inhibition of VEGF receptor tyrosine kinase (axitinib, 4 mg/kg/d, 14 d) had no effect on increased distensibility with relaxin, but caused outward hypertrophic remodeling of PAs from SHRs. These results suggest that relaxin crosses the BBB and activates MMP-2 in brain cortex, which may interact with PAs to increase distensibility. VEGF appears to be involved in remodeling of PAs, but not relaxin-induced increased distensibility.
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Increased SOX2 expression in less differentiated breast carcinomas and their lymph node metastases.
Histopathology
PUBLISHED: 05-20-2013
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SOX2 is a key regulatory gene in embryonic stem cells. Although it has been implicated in cancer progression, its role in breast carcinoma is poorly understood.
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P-cadherin and vimentin are useful basal markers in breast cancers.
Hum. Pathol.
PUBLISHED: 05-13-2013
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Basal-like breast cancer (BLBC) is the breast cancer subtype defined by gene profiling and generates keen clinical interest. Immunohistochemical panels using basal cytokeratins and epidermal growth factor receptor are widely adopted for its identification. Nonetheless, there are concerns about the risk for missing some true BLBCs. Both P-cadherin and vimentin have been proposed as BLBC markers, but their usefulness for BLBC classification has not been well documented. In this study, we evaluated by immunohistochemistry their expression in a large cohort of breast carcinoma. Cancers expressing vimentin or P-cadherin showed BLBC-related morphological features (high grade, presence of necrosis, and lymphocytic infiltration; P < .001 for all except P = .006 for vimentin with lymphocytic infiltration) and immunohistochemical profile (P < .001 for all markers tested except P = .007 for vimentin with human epidermal growth factor receptor 2). Concordantly, they were significantly associated with BLBC (P < .001 for both). Nonetheless, they did not appear to be good stand-alone BLBC markers. Compared with the commonly used reference panel, the specificity (95.9%) and sensitivity (43.1%) of coexpression of vimentin and P-cadherin were better than most single markers or their combinations tested. Moreover, their coexpression was significantly associated with basal features in non-BLBCs and worse disease-free survival in triple-negative breast cancers (hazard ratio, 2.232; P = .027). This raised the possibility that the vimentin and P-cadherin combination can be used to identify BLBC especially those that were missed by the commonly used basal cytokeratins and epidermal growth factor receptor panel. Together, P-cadherin and vimentin could be adjunctive to the commonly used immunohistochemical surrogates for BLBC identification.
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CX3CL1 expression is associated with poor outcome in breast cancer patients.
Breast Cancer Res. Treat.
PUBLISHED: 05-08-2013
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The significance of chemokines in cancer biology has been widely recognized in recent years. CX3CL1 is a unique subclass of chemokine with complex functions, including recruitment of anti-tumor leukocytes and promoting cancer survival, thus affecting cancer progression in both the directions. It is not clear how these different functions interact in breast cancers. This is further complicated by the heterogeneity of breast cancer, and differential association of CX3CL1 with different subgroups could be present. There is only limited knowledge of CX3CL1 expression profile, its relationship with different biological features, subtypes, and outcomes in breast cancers. In this study, CX3CL1 expression was examined in a large cohort of breast cancers by immunohistochemistry and its association with clinicopathological factors, biomarker expression, and impact on patients survival was assessed. High CX3CL1 expression was detected in 33.3 % (252/757) of primary invasive cancers. In line with its chemo-attractant function, CX3CL1 expression correlated positively with increased tumor infiltrating lymphocytes (TIL) (p = 0.005). In addition, CX3CL1 also correlated positively with adverse features in breast cancers, including lymph node involvement (p = 0.007), high Ki67 (p = 0.002), ?-B crystallin expression (p = 0.008), and luminal B (worse prognosis luminal cancers) subtype (p = 0.024). Consistently, breast cancers with high expression of CX3CL1 were found to have a poorer overall survival (?(2) = 4.797, p = 0.029). Interestingly, the adverse effect of CX3CL1 on outcome appeared to be more prominent in cancers with low TIL. These findings indicated that CX3CL1 could also have a pro-tumor role in breast cancer, despite its previously suggested role in enhancing anti-tumor immunity. The results highlighted the complicated functions of CX3CL1 in breast carcinogenesis. Further studies are needed to clarify the relative contribution of these anti- and pro-tumor functions in order to understand the true prognostic and potential therapeutic values of CX3CL1.
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Copper stabilization in beneficial use of waterworks sludge and copper-laden electroplating sludge for ceramic materials.
Waste Manag
PUBLISHED: 04-30-2013
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A promising strategy for effectively incorporating metal-containing waste materials into a variety of ceramic products was devised in this study. Elemental analysis confirmed that copper was the predominant metal component in the collected electroplating sludge, and aluminum was the predominant constituent of waterworks sludge collected in Hong Kong. The use of waterworks sludge as an aluminum-rich precursor material to facilitate copper stabilization under thermal conditions provides a promising waste-to-resource strategy. When sintering the mixture of copper sludge and the 900°C calcined waterworks sludge, the CuAl2O4 spinel phase was first detected at 650°C and became the predominant product phase at temperatures higher than 850°C. Quantification of the XRD pattern using the Rietveld refinement method revealed that the weight of the CuAl2O4 spinel phase reached over 50% at 850°C. The strong signals of the CuAl2O4 phase continued until the temperature reached 1150°C, and further sintering initiated the generation of the other copper-hosting phases (CuAlO2, Cu2O, and CuO). The copper stabilization effect was evaluated by the copper leachability of the CuAl2O4 and CuO via the prolonged leaching experiments at a pH value of 4.9. The leaching results showed that the CuAl2O4 phase was superior to the CuAlO2 and CuO phases for immobilizing hazardous copper over longer leaching periods. The findings clearly indicate that spinel formation is the most crucial metal stabilization mechanism when sintering multiphase copper sludge with aluminum-rich waterworks sludge, and suggest a promising and reliable technique for reusing both types of sludge waste for ceramic materials.
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Fibrotic focus in breast carcinomas: relationship with prognostic parameters and biomarkers.
Ann. Surg. Oncol.
PUBLISHED: 03-29-2013
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Fibrotic focus (FF) has been observed in breast cancers and is suggested to be an important prognostic marker. However, most of these observations were reported by the same group of investigators with similar sample cohort. The relationship of FF and molecular subtypes as well as its associated prognosis has not been elucidated.
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Neurobehavioral deficits of epidermal growth factor-overexpressing transgenic mice: impact on dopamine metabolism.
Neurosci. Lett.
PUBLISHED: 02-21-2013
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Epidermal growth factor (EGF) and its family member neuregulin-1 are implicated in the etiology of schizophrenia. Our recent pharmacological studies indicate that EGF injections to neonatal and adult rats both induce neurobehavioral deficits relevant to schizophrenia. We, however, did not evaluate the genetic impact of EGF transgene on neurobehavioral traits. Here we analyzed transgenic mice carrying the transgene of mouse EGF cDNA. As compared to control littermates, heterozygous EGF transgenic mice had an increase in EGF mRNA levels and showed significant decreases in prepulse inhibition and context-dependent fear learning, but there were no changes in locomotor behaviors and sound startle responses. In addition, these transgenic mice exhibited higher behavioral sensitivity to the repeated cocaine injections. There were neurochemical alterations in metabolic enzymes of dopamine (i.e., tyrosine hydroxylase, dopa decarboxylase, catechol-O-methyl transferase) and monoamine contents in various brain regions of the EGF transgenic mice, but there were no apparent neuropathological signs in the brain. The present findings rule out the indirect influence of anti-EGF antibody production on the reported behavioral deficits of EGF-injected mice. These results support the argument that aberrant hyper-signals of EGF have significant impact on mouse behavioral traits and dopamine metabolism.
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Effect of pregnancy and nitric oxide on the myogenic vasodilation of posterior cerebral arteries and the lower limit of cerebral blood flow autoregulation.
Reprod Sci
PUBLISHED: 02-18-2013
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Hemorrhage during parturition can lower blood pressure beyond the lower limit of cerebral blood flow (CBF) autoregulation that can cause ischemic brain injury. However, the impact of pregnancy on the lower limit of CBF autoregulation is unknown. We measured myogenic vasodilation, a major contributor of CBF autoregulation, in isolated posterior cerebral arteries (PCAs) from nonpregnant and late-pregnant rats (n = 10/group) while the effect of pregnancy on the lower limit of CBF autoregulation was studied in the posterior cerebral cortex during controlled hemorrhage (n = 8). Pregnancy enhanced myogenic vasodilation in PCA and shifted the lower limit of CBF autoregulation to lower pressures. Inhibition of nitric oxide synthase (NOS) prevented the enhanced myogenic vasodilation during pregnancy but did not affect the lower limit of CBF autoregulation. The shift in the autoregulatory curve to lower pressures during pregnancy is likely protective of ischemic injury during hemorrhage and appears to be independent of NOS.
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Nox2 deficiency prevents hypertension-induced vascular dysfunction and hypertrophy in cerebral arterioles.
Int J Hypertens
PUBLISHED: 02-16-2013
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Oxidative stress is involved in many hypertension-related vascular diseases in the brain, including stroke and dementia. Thus, we examined the role of genetic deficiency of NADPH oxidase subunit Nox2 in the function and structure of cerebral arterioles during hypertension. Arterial pressure was increased in right-sided cerebral arterioles with transverse aortic banding for 4 weeks in 8-week-old wild-type (WT) and Nox2-deficient (-/y) mice. Mice were given N(G)-nitro-L-arginine methyl ester (L-NAME, 10?mg/kg) or vehicle to drink. We measured the reactivity in cerebral arterioles through open cranial window in anesthetized mice and wall cross-sectional area and superoxide levels ex vivo. Aortic constriction increased systolic and pulse pressures in right-sided carotid arteries in all groups of mice. Ethidium fluorescence showed increased superoxide in right-sided cerebral arterioles in WT, but not in Nox2-/y mice. Dilation to acetylcholine, but not sodium nitroprusside, was reduced, and cross-sectional areas were increased in the right-sided arterioles in WT, but were unchanged in Nox2-/y mice. L-NAME reduced dilation to acetylcholine but did not result in hypertrophy in right-sided arterioles of Nox2-/y??mice. In conclusion, hypertension-induced superoxide production derived from Nox2-containing NADPH oxidase promotes hypertrophy and causes endothelial dysfunction in cerebral arterioles, possibly involving interaction with nitric oxide.
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Cysteine (C)-x-C receptor 4 undergoes transportin 1-dependent nuclear localization and remains functional at the nucleus of metastatic prostate cancer cells.
PLoS ONE
PUBLISHED: 01-18-2013
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The G-protein coupled receptor (GPCR), Cysteine (C)-X-C Receptor 4 (CXCR4), plays an important role in prostate cancer metastasis. CXCR4 is generally regarded as a plasma membrane receptor where it transmits signals that support transformation, progression and eventual metastasis. Due to the central role of CXCR4 in tumorigenesis, therapeutics approaches such as antagonist and monoclonal antibodies have focused on receptors that exist on the plasma membrane. An emerging concept for G-protein coupled receptors is that they may localize to and associate with the nucleus where they retain function and mediate nuclear signaling. Herein, we demonstrate that CXCR4 associated with the nucleus of malignant prostate cancer tissues. Likewise, expression of CXCR4 was detected in nuclear fractions among several prostate cancer cell lines, compared to normal prostate epithelial cells. Our studies identified a nuclear pool of CXCR4 and we defined a nuclear transport pathway for CXCR4. We reveal a putative nuclear localization sequence (NLS), RPRK, within CXCR4 that contributed to nuclear localization. Additionally, nuclear CXCR4 interacted with Transportin?1 and Transportin?1-binding to CXCR4 promoted its nuclear translocation. Importantly, G?i immunoprecipitation and calcium mobilization studies indicated that nuclear CXCR4 was functional and participated in G-protein signaling, revealing that the nuclear pool of CXCR4 retained function. Given the suggestion that functional, nuclear CXCR4 may be a mechanism underlying prostate cancer recurrence, increased metastatic ability and poorer prognosis after tumors have been treated with therapy that targets plasma membrane CXCR4, these studies addresses a novel mechanism of nuclear signaling for CXCR4, a novel mechanism of clinical targeting, and demonstrate an active nuclear pool that provides important new information to illuminate what has been primarily clinical reports of nuclear CXCR4.
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Expression of mammaglobin and gross cystic disease fluid protein-15 in breast carcinomas.
Hum. Pathol.
PUBLISHED: 01-17-2013
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Immunohistochemical analysis of gross cystic disease fluid protein-15 (GCDFP-15) and mammaglobin (MGB) is frequently used in routine practice for assessment of metastases or regional recurrences of breast origin. Breast cancer is highly heterogeneous. Expression of these 2 markers in various breast cancer subtypes has not been well studied. In addition, the usefulness of these two markers in combination in detecting breast origin has not been explored. In this study, a large cohort of breast cancers was evaluated for GCDFP-15 and MGB expression, both individually and combined. Their expression was correlated with cancer subtypes, other biomarkers and clinicopathologic parameters. A higher sensitivity for MGB (42.3%) than GCDFP-15 (31.6%) in detecting cancers of breast origin was observed. Combining both increased the sensitivity further, both for primary tumor (53.0%) and for nodal metastases (69.0%). GCDFP-15 was associated significantly with a breast cancer profile of good prognosis tumors, including lower grade (P < .001), pN (P = .029) and Ki-67 (P < .001) as well as negative basal markers expression (P = .043, .009, and .049 for c-Kit, CK5/6 and epidermal growth factor receptor, respectively) and, thus, may not be sensitive for detection of poor prognosis tumors. MGB has the highest expression in HER2-overexpressing cancers (56.6%), and may be a potentially useful marker for this subtype. Nonetheless, both markers showed low expression in the basal like (BLBC) subtype (11.9% and 21.4% for GCDFP-15 and MGB respectively), therefore, the detection of BLBC remains problematic. Negative results need to be interpreted with caution, and correlation with other clinical findings may be required to exclude the possibility of metastatic BLBC.
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The role of the methyltransferase domain of bifunctional restriction enzyme RM.BpuSI in cleavage activity.
PLoS ONE
PUBLISHED: 01-01-2013
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Restriction enzyme (REase) RM.BpuSI can be described as a Type IIS/C/G REase for its cleavage site outside of the recognition sequence (Type IIS), bifunctional polypeptide possessing both methyltransferase (MTase) and endonuclease activities (Type IIC) and endonuclease activity stimulated by S-adenosyl-L-methionine (SAM) (Type IIG). The stimulatory effect of SAM on cleavage activity presents a major paradox: a co-factor of the MTase activity that renders the substrate unsusceptible to cleavage enhances the cleavage activity. Here we show that the RM.BpuSI MTase activity modifies both cleavage substrate and product only when they are unmethylated. The MTase activity is, however, much lower than that of M1.BpuSI and is thought not to be the major MTase for host DNA protection. SAM and sinefungin (SIN) increase the Vmax of the RM.BpuSI cleavage activity with a proportional change in Km, suggesting the presence of an energetically more favorable pathway is taken. We further showed that RM.BpuSI undergoes substantial conformational changes in the presence of Ca(2+), SIN, cleavage substrate and/or product. Distinct conformers are inferred as the pre-cleavage/cleavage state (in the presence of Ca(2+), substrate or both) and MTase state (in the presence of SIN and substrate, SIN and product or product alone). Interestingly, RM.BpuSI adopts a unique conformation when only SIN is present. This SIN-bound state is inferred as a branch point for cleavage and MTase activity and an intermediate to an energetically favorable pathway for cleavage, probably through increasing the binding affinity of the substrate to the enzyme under cleavage conditions. Mutation of a SAM-binding residue resulted in altered conformational changes in the presence of substrate or Ca(2+) and eliminated cleavage activity. The present study underscores the role of the MTase domain as facilitator of efficient cleavage activity for RM.BpuSI.
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Structure determination and biochemical characterization of a putative HNH endonuclease from Geobacter metallireducens GS-15.
PLoS ONE
PUBLISHED: 01-01-2013
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The crystal structure of a putative HNH endonuclease, Gmet_0936 protein from Geobacter metallireducens GS-15, has been determined at 2.6 Å resolution using single-wavelength anomalous dispersion method. The structure contains a two-stranded anti-parallel ?-sheet that are surrounded by two helices on each face, and reveals a Zn ion bound in each monomer, coordinated by residues Cys38, Cys41, Cys73, and Cys76, which likely plays an important structural role in stabilizing the overall conformation. Structural homologs of Gmet_0936 include Hpy99I endonuclease, phage T4 endonuclease VII, and other HNH endonucleases, with these enzymes sharing 15-20% amino acid sequence identity. An overlay of Gmet_0936 and Hpy99I structures shows that most of the secondary structure elements, catalytic residues as well as the zinc binding site (zinc ribbon) are conserved. However, Gmet_0936 lacks the N-terminal domain of Hpy99I, which mediates DNA binding as well as dimerization. Purified Gmet_0936 forms dimers in solution and a dimer of the protein is observed in the crystal, but with a different mode of dimerization as compared to Hpy99I. Gmet_0936 and its N77H variant show a weak DNA binding activity in a DNA mobility shift assay and a weak Mn²?-dependent nicking activity on supercoiled plasmids in low pH buffers. The preferred substrate appears to be acid and heat-treated DNA with AP sites, suggesting Gmet_0936 may be a DNA repair enzyme.
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Inhibition of PPAR? during rat pregnancy causes intrauterine growth restriction and attenuation of uterine vasodilation.
Front Physiol
PUBLISHED: 01-01-2013
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Decreased peroxisome proliferator-activated receptor gamma (PPAR?) activity is thought to have a major role in preeclampsia through abnormal placental development. However, the role of PPAR? in adaptation of the uteroplacental vasculature that may lead to placental hypoperfusion and fetal growth restriction during pregnancy is not known. Here, pregnant Sprague-Dawley rats (n = 11/group) were treated during the second half of pregnancy with the PPAR? inhibitor GW9662 (10 mg/kg/day in food) or vehicle. Pregnancy outcome and PPAR? mRNA, vasodilation and structural remodeling were determined in maternal uterine and mesenteric arteries. PPAR? was expressed in uterine vascular tissue of both non-pregnant and pregnant rats with ~2-fold greater expression in radial vs. main uterine arteries. PPAR? mRNA levels were significantly higher in uterine compared to mesenteric arteries. GW9662 treatment during pregnancy did not affect maternal physiology (body weight, glucose, blood pressure), mesenteric artery vasodilation or structural remodeling of uterine and mesenteric vessels. Inhibition of PPAR? for the last 10 days of gestation caused decreased fetal weights on both day 20 and 21 of gestation that was associated with impaired vasodilation of radial uterine arteries in response to acetylcholine and sodium nitroprusside. These results define an essential role of PPAR? in the control of uteroplacental vasodilatory function during pregnancy, an important determinant of blood flow to the placenta and fetus. Strategies that target PPAR? activation in the uterine circulation could have important therapeutic potential in treatment of pregnancies complicated by hypertension, diabetes or preeclampsia.
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Deficiency of Nox2 prevents angiotensin II-induced inward remodeling in cerebral arterioles.
Front Physiol
PUBLISHED: 01-01-2013
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Angiotensin II is an important determinant of inward remodeling in cerebral arterioles. Many of the vascular effects of angiotensin II are mediated by reactive oxygen species (ROS) generated from homologs of NADPH oxidase with Nox2 predominating in small arteries and arterioles. Therefore, we tested the hypothesis that superoxide generated by Nox2 plays a role in angiotensin II-induced cerebral arteriolar remodeling. We examined Nox2-deficient and wild-type (WT) mice in which a pressor or a non-pressor dose of angiotensin II (1000 or 200 ng/kg/day) or saline was infused for 4 weeks via osmotic minipumps. Systolic arterial pressure was measured by a tail-cuff method. Pressure and diameter of cerebral arterioles were measured through an open cranial window in anesthetized mice. Cross-sectional area (by histology) and superoxide level (by hydroethidine staining) of cerebral arterioles were determined ex vivo. The pressor, but not the non-pressor, dose of angiotensin II significantly increased systolic arterial pressure in both WT and Nox2-deficient mice. Both doses of angiotensin II increased superoxide levels and significantly reduced external diameter in maximally dilated cerebral arterioles in WT mice. Increased superoxide and inward remodeling were prevented in Nox2-deficient mice. Moreover, only the pressor dose of AngII increased cross-sectional area of arteriolar wall in WT mice and was prevented in Nox2-deficient mice. In conclusion, superoxide derived from Nox2-containing NADPH oxidase plays an important role in angiotensin II-mediated inward remodeling in cerebral arterioles. This effect appears to be independent of pressure and different from that of hypertrophy.
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Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine: structural, spectroscopic, and theoretical studies.
Inorg Chem
PUBLISHED: 10-24-2011
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Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine (ON(^)N) and tetradentate thioether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS4), [Ru(ON(^)N)([14]aneS4)](2+) [ON(^)N = 2-(2-nitrosophenyl)pyridine (2a), 10-nitrosobenzo[h]quinoline (2b), 2-(2-nitroso-4-methylphenyl)pyridine, (2c), 2-(2-nitrosophenyl)-5-(trifluoromethyl)pyridine (2d)] and analogues with the 1,4,7-trithiacyclononane ([9]aneS3)/tert-butylisocyanide ligand set, [Ru(ON(^)N)([9]aneS3)(C?N(t)Bu)](2+) (4a and 4b), have been prepared by insertion of a nitrosonium ion (NO(+)) into the Ru-aryl bond of cyclometalated ruthenium(II) complexes. The molecular structures of the ON(^)N-ligated complexes 2a and 2b reveal that (i) the ON(^)N ligands behave as bidentate chelates via the two N atoms and the bite angles are 86.84(18)-87.83(16)° and (ii) the Ru-N(NO) and N-O distances are 1.942(5)-1.948(4) and 1.235(6)-1.244(5) Å, respectively. The Ru-N(NO) and N-O distances, together with ?(N?O), suggest that the coordinated ON(^)N ligands in this work are neutral moiety (ArNO)(0) rather than monoanionic radical (ArNO)(•-) or dianion (ArNO)(2-) species. The nitrosated complexes 2a-2d show moderately intense absorptions centered at 463-484 nm [?(max) = (5-6) × 10(3) dm(3) mol(-1) cm(-1)] and a clearly discriminable absorption shoulder around 620 nm (?(max) = (6-9) × 10(2) dm(3) mol(-1) cm(-1)), which tails up to 800 nm. These visible absorptions are assigned as a mixing of d(Ru) ? ON(^)N metal-to-ligand charge-transfer and ON(^)N intraligand transitions on the basis of time-dependent density functional theory (TD-DFT) calculations. The first reduction couples of the nitrosated complexes range from -0.53 to -0.62 V vs Cp(2)Fe(+/0), which are 1.1-1.2 V less negative than that for [Ru(bpy)([14]aneS4)](2+) (bpy = 2,2-bipyridine). Both electrochemical data and DFT calculations suggest that the lowest unoccupied molecular orbitals of the nitrosated complexes are ON(^)N-centered. Natural population analysis shows that the amount of positive charge on the Ru centers and the [Ru([14]aneS4)] moieties in 2a and 2b is larger than that in [Ru(bpy)([14]aneS4)](2+). According to the results of the structural, spectroscopic, electrochemical, and theoretical investigations, the ON(^)N ligands in this work have considerable ?-acidic character and behave as better electron acceptors than bpy.
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Phyllodes tumours of the breast - differentiating features in core needle biopsy.
Histopathology
PUBLISHED: 09-14-2011
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To investigate the usefulness of histological features in the differentiation of fibroepithelial lesions of the breast (phyllodes tumours and fibroadenomas) in core needle biopsies.
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Increased alpha-B-crystallin expression in mammary metaplastic carcinomas.
Histopathology
PUBLISHED: 09-03-2011
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?Mammary metaplastic carcinoma is a rare breast carcinoma, and may present diagnostic difficulty. Alpha-B-crystallin has been recently reported to be expressed in basal-like and metaplastic carcinomas.
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Accessing the genomic effects of naked nanoceria in murine neuronal cells.
Nanomedicine
PUBLISHED: 08-08-2011
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Cerium oxide nanoparticles (nanoceria) are engineered nanoparticles whose versatility is due to their unique redox properties. We and others have demonstrated that naked nanoceria can act as antioxidants to protect cells against oxidative damage. Although the redox properties may be beneficial, the genome-wide effects of nanoceria on gene transcription and associated biological processes remain elusive. Here we applied a functional genomic approach to examine the genome-wide effects of nanoceria on global gene transcription and cellular functions in mouse neuronal cells. Importantly, we demonstrated that nanoceria induced chemical- and size-specific changes in the murine neuronal cell transcriptome. The nanoceria contributed more than 83% of the population of uniquely altered genes and were associated with a unique spectrum of genes related to neurological disease, cell cycle control, and growth. These observations suggest that an in-depth assessment of potential health effects of naked nanoceria and other naked nanoparticles is both necessary and imminent.
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Percutaneous computed tomography-guided cryotherapy of thoracic masses in nonsurgical candidates: experience in 19 patients.
J. Formos. Med. Assoc.
PUBLISHED: 07-12-2011
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Percutaneous cryotherapy has become a minimally invasive treatment option for unresectable lung malignancies. We report the experience and outcomes with percutaneous computed tomography (CT)-guided cryotherapy of primary lung malignancies, as well as recurrence and metastases, in patients ineligible for surgery.
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Characterization and crystal structure of the type IIG restriction endonuclease RM.BpuSI.
Nucleic Acids Res.
PUBLISHED: 06-30-2011
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A type IIG restriction endonuclease, RM.BpuSI from Bacillus pumilus, has been characterized and its X-ray crystal structure determined at 2.35Å resolution. The enzyme is comprised of an array of 5-folded domains that couple the enzymes N-terminal endonuclease domain to its C-terminal target recognition and methylation activities. The REase domain contains a PD-x(15)-ExK motif, is closely superimposable against the FokI endonuclease domain, and coordinates a single metal ion. A helical bundle domain connects the endonuclease and methyltransferase (MTase) domains. The MTase domain is similar to the N6-adenine MTase M.TaqI, while the target recognition domain (TRD or specificity domain) resembles a truncated S subunit of Type I R-M system. A final structural domain, that may form additional DNA contacts, interrupts the TRD. DNA binding and cleavage must involve large movements of the endonuclease and TRD domains, that are probably tightly coordinated and coupled to target site methylation status.
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Decomposing flux distributions into elementary flux modes in genome-scale metabolic networks.
Bioinformatics
PUBLISHED: 06-17-2011
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Elementary flux mode (EFM) is a fundamental concept as well as a useful tool in metabolic pathway analysis. One important role of EFMs is that every flux distribution can be decomposed into a set of EFMs and a number of methods to study flux distributions originated from it. Yet finding such decompositions requires the complete set of EFMs, which is intractable in genome-scale metabolic networks due to combinatorial explosion.
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Ankle-brachial index as an indicator of arterial stiffness in patients without peripheral artery disease.
Angiology
PUBLISHED: 06-15-2011
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We tested the hypothesis that the Ankle-Brachial Index (ABI) in patients without peripheral arterial disease ([PAD] ABI > 1.0) is an indicator of arterial stiffness. Fifty-five patients had measurement of carotid pulse wave contour, pulse wave velocity (PWV), and ABI. Vascular stiffness as assessed by augmentation index (AIx) showed a significant (P = .002) inverse correlation with ABI. Dichotomizing ABI into groups above and below the median showed that persons with a lower ABI, >1.0 to 1.5 (n = 27) had a significantly (P < .01) higher AIx than those with a higher ABI > 1.5 (n = 28). In contrast, vascular stiffness assessed by brachial-ankle or carotid femoral PWV did not correlate with ABI. In summary, ABI is an indicator of arterial stiffness assessed by AIx. Vascular changes detected by AIx are not the same as those detected by PWV. Assessment of ABI may have utility in cardiovascular risk assessment in patients without PAD.
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TSPYL2 is important for G1 checkpoint maintenance upon DNA damage.
PLoS ONE
PUBLISHED: 06-06-2011
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Nucleosome assembly proteins play important roles in chromatin remodeling, which determines gene expression, cell proliferation and terminal differentiation. Testis specific protein, Y-encoded-like 2 (TSPYL2) is a nucleosome assembly protein expressed in neuronal precursors and mature neurons. Previous studies have shown that TSPYL2 binds cyclin B and inhibits cell proliferation in cultured cells suggesting a role in cell cycle regulation. To investigate the physiological significance of TSPYL2 in the control of cell cycle, we generated mice with targeted disruption of Tspyl2. These mutant mice appear grossly normal, have normal life span and do not exhibit increased tumor incidence. To define the role of TSPYL2 in DNA repair, checkpoint arrest and apoptosis, primary embryonic fibroblasts and thymocytes from Tspyl2 deficient mice were isolated and examined under unperturbed and stressed conditions. We show that mutant fibroblasts are impaired in G1 arrest under the situation of DNA damage induced by gamma irradiation. This is mainly attributed to the defective activation of p21 transcription despite proper p53 protein accumulation, suggesting that TSPYL2 is additionally required for p21 induction. TSPYL2 serves a biological role in maintaining the G1 checkpoint under stress condition.
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Twenty-year prevalence of diabetes mellitus and hypertension in patients receiving shock-wave lithotripsy for urolithiasis.
BJU Int.
PUBLISHED: 06-02-2011
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To compare the prevalence of hypertension and diabetes mellitus (DM) in patients treated with an unmodified HM-3 lithotripter (USWL) and a second-generation modified HM-3 lithotripter (MSWL) 20 years ago at our Centre with that in the provincial population. To determine whether the type of lithotripter was differentially associated with the development of these sequelae.
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Relaxin causes selective outward remodeling of brain parenchymal arterioles via activation of peroxisome proliferator-activated receptor-?.
FASEB J.
PUBLISHED: 05-20-2011
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Brain parenchymal arterioles (PAs), but not pial arteries, undergo hypotrophic outward remodeling during pregnancy that involves peroxisome proliferator-activated receptor-? (PPAR?) activation. Relaxin, a peptide hormone produced during pregnancy, is involved in systemic and renal artery remodeling and activates PPAR? in vitro. Thus, we hypothesized that relaxin is involved in the selective outward remodeling of PAs through a PPAR?-dependent mechanism. Nonpregnant rats were treated with relaxin (4 ?g/h, osmotic minipump), relaxin plus PPAR? inhibitor GW9662 (10 mg/kg/d), or vehicle for 10 d. Vascular function and structure were compared in isolated and pressurized middle cerebral arteries (MCAs) and PAs taken from the same animals. Relaxin treatment increased serum relaxin to the level of pregnancy (54 ng/ml) and increased passive wall thickness (hypertrophy; 70 ± 5 vs. 54 ± 4 ?m in vehicle; P<0.05) and inner diameter (outward remodeling; 10.6 ± 0.5 vs. 8.0 ± 0.6 ?m in vehicle; P<0.05) in PAs, but not in MCAs. This hypertrophic outward remodeling was prevented by GW9662 that had diameters (57 ± 3 ?m) and wall thickness (8.6 ± 1.0 ?m) similar to vehicle. GW9662 also prevented relaxin-induced changes in PPAR? target gene expression. These results suggest that relaxin produced during pregnancy may be partly responsible for selective remodeling of PAs during pregnancy through a mechanism involving PPAR?
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Biopsy sampling of breast lesions: comparison of core needle- and vacuum-assisted breast biopsies.
Breast Cancer Res. Treat.
PUBLISHED: 04-28-2011
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Needle biopsy is now the initial investigation of choice for the pre-operative diagnosis of breast lesions. This includes core needle biopsy (CNB) and vacuum-assisted biopsy (VAB) with or without radiologic assistance. The performance indices of both of these biopsy techniques were evaluated. In a large cohort of patients with breast lesions including 464 cases (285 CNB and 179 VAB), with confirmed outcomes, the diagnostic accuracy was compared using parameters including quantitation of the sampling based on the total number of cores taken, cores containing breast parenchyma, and cores with lesion; and non-epithelial changes including necrosis and calcification. CNB showed a 99% PPV, 94% NPV, 96% sensitivity, and 99% specificity, whereas VAB demonstrated a 100% PPV, 100% NPV, 100% sensitivity, and 100% specificity. The correct diagnosis in CNB was proportional to the number of cores extracted, whereas accuracy of VAB was independent of the total number of cores taken. There was a positive correlation between the presence of calcification and malignancy in CNB, but not detected under VAB. CNB and VAB were equally efficient in palpable lesions, in detecting necrosis, and calcification. Large calcification was found to be associated with malignancy in both CNB and VAB. In non-palpable lesions, VAB was more effective in the detection of calcification. The diagnostic accuracy of VAB appeared to be independent of number of cores sampled, whereas CNB required a minimum of 3-4 cores to achieve high diagnostic accuracy.
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The social context of smoking cessation in China: an exploratory interview study.
Tob Control
PUBLISHED: 04-01-2011
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China has the largest population of smokers in the world. Little previous research has explored the cultural challenges in encouraging smoking cessation in China. This study aimed to explore and generate research questions about culturally distinctive beliefs and barriers to smoking cessation.
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A type IV modification-dependent restriction enzyme SauUSI from Staphylococcus aureus subsp. aureus USA300.
Nucleic Acids Res.
PUBLISHED: 03-17-2011
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A gene encoding a putative DNA helicase from Staphylococcus aureus USA300 was cloned and expressed in Escherichia coli. The protein was purified to over 90% purity by chromatography. The purified enzyme, SauUSI, predominantly cleaves modified DNA containing 5mC and 5-hydroxymethylcytosine. Cleavage of 5mC-modified plasmids indicated that the sites S5mCNGS (S?=?C or G) are preferentially digested. The endonuclease activity requires the presence of adenosine triphosphate (ATP) or dATP whereas the non-hydrolyzable ?-S-ATP does not support activity. SauUSI activity was inhibited by ethylenediaminetetraacetic acid. It is most active in Mg(++) buffers. No companion methylase gene was found near the SauUSI restriction gene. The absence of a cognate methylase and cleavage of modified DNA indicate that SauUSI belongs to type IV restriction endonucleases, a group that includes EcoK McrBC and Mrr. SauUSI belongs to a family of highly similar homologs found in other sequenced S. aureus, S. epidermidis and S. carnosus genomes. More distant SauUSI orthologs can be found in over 150 sequenced bacterial/archaea genomes. Finally, we demonstrated the biological function of the type IV REase in restricting 5mC-modified plasmid DNA by transformation into clinical S. aureus strain SA564, and in restricting phage ? infection when the endonuclease is expressed in E. coli.
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Modified radiology-guided percutaneous gastrostomy (MRPG) for patients with complete obstruction of the upper digestive tract and who are without endoscopic or nasogastric access.
Korean J Radiol
PUBLISHED: 03-03-2011
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We wanted to report on our experience with modified radiology-guided percutaneous gastrostomy (MRPG) without endoscopic or nasogastric access for treating patients with complete obstruction of the upper digestive tract.
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Subcellular localization of SUN2 is regulated by lamin A and Rab5.
PLoS ONE
PUBLISHED: 01-05-2011
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SUN2 is an inner nuclear membrane protein with a conserved Sad1/UNC-84 homology SUN-domain at the C-terminus. Intriguingly, SUN2 has also been reported to interact with Rab5, which localizes in early endosomes. To clarify the dual subcellular localization of SUN2, we investigated its localization in lamin A/C deficient cells rescued with lamin A or lamin C isoform, and in HeLa cells transfected with Rab5 or its mutants. We found that expression of lamin A but not lamin C partly restored the nuclear envelope localization of SUN2. SUN2 was redistributed to endosomes upon overexpression of Rab5, but remained on the nuclear envelope when the SUN domain was deleted. To explore the physiological function of SUN2 in vesicle trafficking and endocytosis, we demonstrated the colocalization of endogenous SUN2 and Rab5. Moreover, overexpression of SUN2 stimulated the uptake of transferrin while suppression of SUN2 expression attenuated the process. These findings support a role of SUN2 in endocytosis.
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Cerebral vascular adaptation to pregnancy and its role in the neurological complications of eclampsia.
J. Appl. Physiol.
PUBLISHED: 11-11-2010
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The cerebral circulation has a central role in mediating the neurological complications of eclampsia, yet our understanding of how pregnancy and preeclampsia affect this circulation is severely limited. Here, we show that pregnancy causes outward remodeling of penetrating arterioles and increased capillary density in the brain due to activation of peroxisome proliferator-activated receptor-? (PPAR?), a transcription factor involved in cerebrovascular remodeling and highly activated in pregnancy. Pregnancy-induced PPAR? activation also significantly affected cerebral hemodynamics, decreasing vascular resistance and increasing cerebral blood flow by ?40% in response to acute hypertension that caused breakthrough of autoregulation. These structural and hemodynamic changes in the brain during pregnancy were associated with substantially increased blood-brain barrier permeability, an effect that could promote passage of damaging proteins into the brain and cause the neurological complications of eclampsia, including seizure.
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Smoking cessation intervention practices in Chinese physicians: do gender and smoking status matter?
Health Soc Care Community
PUBLISHED: 09-09-2010
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Healthcare settings provide a major arena for administering smoking cessation interventions. However, few studies have reported differences in the frequency of practice in healthcare professionals by gender and smoking status. This might also be influenced by a difference in smoking prevalence by gender, especially in China and other developing countries. This study examined factors associated with the frequency of cessation intervention practices by smoking status among Chinese physicians in men and women. A cross-sectional survey was conducted in 2006 in physicians with direct patient contact from nine hospitals in Guangzhou with a response rate of 60.8%. Significantly more female physicians who were non-smokers (79.7%) reported "initiation and/or advice" smoking cessation interventions than male physicians who were smokers (71.2%) and non-smokers (71.6%). Factors significantly associated with "initiation and/or advice" were prior smoking cessation training (OR = 4.2, 95% CI 1.8-9.6) and lack of knowledge to help patients to quit (OR = 0.4, 95% CI 0.2-0.9) among male physicians who smoked; and organisational support (OR = 1.7, 95% CI 1.3-2.2) and successful past experience (OR = 0.4, 95% CI 0.2-1.0) among male physicians who did not smoke. Among female physicians who did not smoke, significant factors were agreeing that quitting smoking is the most cost-effective way to prevent chronic disease and cancer (OR = 3.0, 95% CI 1.4-6.1), helping patients stop smoking is part of expected role and responsibility (OR = 2.0, 95% CI 1.0-3.7), lack of knowledge to help patients to quit (OR = 0.5, 95% CI 0.2-1.0) and organisational support (OR = 1.3, 95% CI 1.0-1.6) for non-smoking female physicians. This study is the first to show that male physicians were less likely to provide smoking cessation counselling regardless of their smoking status while non-smoking female physicians were more active in advising patients on quitting. The findings highlight the need for developing tailored smoking cessation training programmes for physicians according to their smoking status and gender in China.
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Asymmetric DNA recognition by the OkrAI endonuclease, an isoschizomer of BamHI.
Nucleic Acids Res.
PUBLISHED: 09-09-2010
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Restriction enzymes share little or no sequence homology with the exception of isoschizomers, or enzymes that recognize and cleave the same DNA sequence. We present here the structure of a BamHI isoschizomer, OkrAI, bound to the same DNA sequence (TATGGATCCATA) as that cocrystallized with BamHI. We show that OkrAI is a more minimal version of BamHI, lacking not only the N- and C-terminal helices but also an internal 3(10) helix and containing ?-strands that are shorter than those in BamHI. Despite these structural differences, OkrAI recognizes the DNA in a remarkably similar manner to BamHI, including asymmetric contacts via C-terminal arms that appear to compete for the minor groove. However, the arms are shorter than in BamHI. We observe similar DNA-binding affinities between OkrAI and BamHI but OkrAI has higher star activity (at 37°C) compared to BamHI. Together, the OkrAI and BamHI structures offer a rare opportunity to compare two restriction enzymes that work on exactly the same DNA substrate.
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Natural and engineered nicking endonucleases--from cleavage mechanism to engineering of strand-specificity.
Nucleic Acids Res.
PUBLISHED: 08-30-2010
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Restriction endonucleases (REases) are highly specific DNA scissors that have facilitated the development of modern molecular biology. Intensive studies of double strand (ds) cleavage activity of Type IIP REases, which recognize 4-8?bp palindromic sequences, have revealed a variety of mechanisms of molecular recognition and catalysis. Less well-studied are REases which cleave only one of the strands of dsDNA, creating a nick instead of a ds break. Naturally occurring nicking endonucleases (NEases) range from frequent cutters such as Nt.CviPII (^CCD; ^ denotes the cleavage site) to rare-cutting homing endonucleases (HEases) such as I-HmuI. In addition to these bona fida NEases, individual subunits of some heterodimeric Type IIS REases have recently been shown to be natural NEases. The discovery and characterization of more REases that recognize asymmetric sequences, particularly Types IIS and IIA REases, has revealed recognition and cleavage mechanisms drastically different from the canonical Type IIP mechanisms, and has allowed researchers to engineer highly strand-specific NEases. Monomeric LAGLIDADG HEases use two separate catalytic sites for cleavage. Exploitation of this characteristic has also resulted in useful nicking HEases. This review aims at providing an overview of the cleavage mechanisms of Types IIS and IIA REases and LAGLIDADG HEases, the engineering of their nicking variants, and the applications of NEases and nicking HEases.
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Complications of fluoroscopically guided percutaneous gastrostomy with large-bore balloon-retained catheter in patients with head and neck tumors.
J. Formos. Med. Assoc.
PUBLISHED: 08-17-2010
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To review the complications, mortality rate and nutritional status of patients with head and neck cancer after fluoroscopically guided percutaneous gastrostomy (FPG).
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Can the analysis of ERCC1 expression contribute to individualized therapy in nasopharyngeal carcinoma?
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 06-03-2010
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To analyze the expression of excision repair cross-complementation group 1 (ERCC1) protein in predicting the clinical outcome of nasopharyngeal carcinoma (NPC).
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Papillary lesions of the breast--accuracy of core biopsy.
Histopathology
PUBLISHED: 05-13-2010
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To assess the accuracy of diagnosing papillary breast lesions in core needle biopsy.
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Attentional bias towards negative affect stimuli and reactive aggression in male batterers.
Psychiatry Res
PUBLISHED: 03-06-2010
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Spouse abuse is listed as a V code in DSM-IV-TR and worthy of further clinical investigation, although research has focused predominantly on the victims of family violence rather than the batterers themselves. This study tests the hypotheses that (a) batterers have a neurocognitive bias favoring negative affect (aggressive) stimuli and (b) batterers are more characterized by reactive than proactive aggression. Tasks were administered to 23 male batterers and 24 controls to assess attentional bias to both negative affect stimuli (emotional Stroop) and affectively neutral stimuli (cognitive Stroop). Batterers relative to controls showed longer reaction times in naming the color of negative affect words than affectively neutral words. No such abnormality was observed for the non-affective cognitive control task. Results remained significant after controlling for comorbid depression. Batterers scored significantly higher on reactive (but not proactive) aggression. Results suggest that batterers may have a bias in allocating more attentional resources to aggressive words, potentially making them over-sensitive to negative affect stimuli in the environment. Future treatment programs addressing this neurocognitive abnormality may be more successful in reducing spouse abuse.
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Unusual target site disruption by the rare-cutting HNH restriction endonuclease PacI.
Structure
PUBLISHED: 02-21-2010
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The crystal structure of the rare-cutting HNH restriction endonuclease PacI in complex with its eight-base-pair target recognition sequence 5-TTAATTAA-3 has been determined to 1.9 A resolution. The enzyme forms an extended homodimer, with each subunit containing two zinc-bound motifs surrounding a betabetaalpha-metal catalytic site. The latter is unusual in that a tyrosine residue likely initiates strand cleavage. PacI dramatically distorts its target sequence from Watson-Crick duplex DNA base pairing, with every base separated from its original partner. Two bases on each strand are unpaired, four are engaged in noncanonical A:A and T:T base pairs, and the remaining two bases are matched with new Watson-Crick partners. This represents a highly unusual DNA binding mechanism for a restriction endonuclease, and implies that initial recognition of the target site might involve significantly different contacts from those visualized in the DNA-bound cocrystal structures.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.