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Find video protocols related to scientific articles indexed in Pubmed.
Pre-hematopoietic stem cell transplant lung function and pulmonary complications in children.
Ann Am Thorac Soc
PUBLISHED: 11-12-2014
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Rationale: Pulmonary complications are a significant cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Objectives: The relationship between pre-transplant pulmonary function tests (PFT) and development of post-transplant pulmonary complications in children was studied. Methods: This is a retrospective single institution cohort study of 410 patients who underwent pre-transplant PFT and were followed up to 10 years post-transplant. Measurements and Main Results: Pulmonary complications were observed in 174 (42%) patients. Children with pulmonary complications had significantly lower FEF25-75% (P = 0.02) derived using conventional predicted equations for age, and the Global Lung Initiative-2012 predicted equations (P = 0.01). T-cell depletion (P = 0.001), acute grade 3-4 graft-versus-host disease (GVHD; P = 0.008), and chronic GVHD (P = 0.01) increased risk for pulmonary complications. Patients who had pulmonary complications had a 2.8-fold increased risk of mortality (P < 0.0001). The cumulative incidence of death due to pulmonary complications was significantly higher in children who had low lung volumes, functional residual capacity (FRC) < 50% (P = 0.005), total lung capacity (TLC) < 50% (P = 0.0002), residual volume (RV) < 50% (P = 0.007), and T-cell depletion (P = 0.01). Lower forced expiratory volume in one second (FEV1; P = 0.0005), forced vital capacity (FVC; P = 0.0005), TLC (P < 0.0001), RV < 50% (P = 0.01), and restrictive lung disease (RLD; P = 0.01) predicted worse overall survival. Conclusions: Abnormal pre-transplant PFT significantly increased risk post-transplant. These patients may benefit from modified transplant strategies to reduce morbidity and mortality.
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Cognitive Outcome After Pediatric Stem-Cell Transplantation: Impact of Age and Total-Body Irradiation.
J. Clin. Oncol.
PUBLISHED: 11-12-2014
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To examine the influence of age and conditioning with total-body irradiation (TBI) on the trajectory of cognitive functioning after treatment with pediatric hematopoietic stem-cell transplantation (SCT).
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TOX2 regulates human natural killer cell development by controlling T-BET expression.
Blood
PUBLISHED: 10-30-2014
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Thymocyte selection-associated high mobility group box protein family member 2 (TOX2) is a transcription factor belonging to the TOX family that shares a highly conserved high mobility group DNA binding domain with the other TOX members. While TOX1 has been shown to be an essential regulator of T-cell and natural killer (NK) cell differentiation in mice, little is known about the roles of the other TOX family members in lymphocyte development, particularly in humans. In this study, we found that TOX2 was preferentially expressed in mature human NK cells and was upregulated during in vitro differentiation of NK cells from human umbilical cord blood (UCB)-derived CD34(+) cells. Gene silencing of TOX2 intrinsically hindered the transition between early developmental stages of NK cells, while overexpression of TOX2 enhanced the development of mature NK cells from UCB CD34(+) cells. We subsequently found that TOX2 was independent of ETS-1 but could directly upregulate the transcription of TBX21 (encoding T-BET). Overexpression of T-BET rescued the TOX2 knockdown phenotypes. Given the essential function of T-BET in NK cell differentiation, TOX2 therefore plays a crucial role in controlling normal NK cell development by acting upstream of TBX21 transcriptional regulation.
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Antidiabetic Effect of Schisandrae Chinensis Fructus Involves Inhibition of the Sodium Glucose Cotransporter.
Drug Dev. Res.
PUBLISHED: 10-10-2014
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Preclinical Research Schisandrae Chinensis Fructus (SCF), the fruit of Schisandra chinensis (Turcz.) Baill. (family Schisandraceae) is traditionally used as a tonic and antidiabetic agent in Asia. In this study, SCF was investigated for its effects on sodium glucose cotransporters 1 and 2 (SGLT 1 and 2) expressed in a COS-7 cell line for its specificity in inhibiting SGLT2, which is a novel mechanism to screen for potential antidiabetic agents. Using a bioassay-guided fractionation, we then tried to isolate and identify the active fraction(s)/component(s). The ethanol extract of SCF at a concentration of 1?mg/mL significantly inhibited 89% of SGLT1 and 73% of SGLT2 activities in a [(14) C]-?-methyl-d-glucopyranoside ([(14) C]-AMG) uptake assay. Fractionation of the ethanol extract yielded nine fractions, of which F8, at a concentration of 1?mg/mL, was specific in inhibiting SGLT 2 (42% inhibition, P?
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NK Cell Genotype and Phenotype at Diagnosis of Acute Lymphoblastic Leukemia Correlate with Postinduction Residual Disease.
Clin. Cancer Res.
PUBLISHED: 10-03-2014
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Not all natural killer (NK) cells are equally cytotoxic against leukemia because of differences in receptor gene content and surface expression. We correlated NK cell genotype and phenotype at diagnosis of childhood acute lymphoblastic leukemia (ALL) with minimal residual disease (MRD) after induction chemotherapy.
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Relationship between intrapartum transperineal ultrasound measurement of angle of progression and head-perineum distance with correlation to conventional clinical parameters of labor progress and time to delivery.
J. Matern. Fetal. Neonatal. Med.
PUBLISHED: 09-29-2014
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Abstract Objective: To assess whether angle of progression (AOP) and head-perineum distance (HPD) measured by intrapartum transperineal ultrasound (ITU) correlate with clinical fetal head station (station); and whether AOP versus HPD varies during uterine contraction and relaxation. In a subset of primipaorus women, whether these ITU parameters correlate with time to normal spontaneous delivery (TD). Methods: We evaluated prospectively 100 primiparous and multiparous women at term in active labor. Transabdominal and transperineal ultrasound (sagittal and transverse plane) were used to measure fetal head position and ITU parameters, respectively. Digitally palpated station and cervical dilatation were also noted. The results were compared using regression and correlation coefficients. Results: Station was moderately correlated with AOP (r?=?0.579) and HPD (r?=?-0.497). AOP was highly correlated with HPD during uterine contraction (r?=?-0.703) and relaxation (r?=?-0.647). In the subgroup of primiparous women, natural log of TD has the highest correlation with HPD and AOP during uterine contraction (r?=?0.742), making prediction of TD similar to that of using cervical dilatation. Conclusion: ITU parameters were moderately correlated with station. There was constant high correlation between AOP and HPD. Prediction of TD in primiparous women using ITU parameters was similar to that of using cervical dilatation.
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Prognostic factors in children with acute myeloid leukaemia and excellent response to remission induction therapy.
Br. J. Haematol.
PUBLISHED: 08-28-2014
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Minimal residual disease (MRD) is a strong prognostic factor in children and adolescents with acute myeloid leukaemia (AML) but nearly one-quarter of patients who achieve MRD-negative status still relapse. The adverse prognostic factors among MRD-negative patients remain unknown. We analysed the AML02 study cohort to identify demographic and genetic prognostic factors. Among the presenting features, certain 11q23 abnormalities, such as t(6;11) and t(10;11), acute megakaryoblastic leukaemia without the t(1;22), and age ?10 years were associated with inferior outcome in patients who had MRD-negative status after either remission induction I or II. By contrast, those with rearrangement of CBF genes had superior outcome. Our study identifies patient populations for whom close post-remission MRD monitoring to detect and treat emerging relapse and adjustment in treatment intensity might be indicated.
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Clinical utility of the Chinese Strengths and Weaknesses of ADHD-Symptoms and Normal-Behaviors questionnaire (SWAN) when compared with DISC-IV.
Neuropsychiatr Dis Treat
PUBLISHED: 08-21-2014
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Attention-deficit/hyperactivity disorder (ADHD) is a common and impairing child and adolescent psychiatric disorder. Early identification and prompt treatment are essential. Rating scales are commonly used by clinicians and researchers to assess ADHD children.
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Outcomes of Children With BCR-ABL1-Like Acute Lymphoblastic Leukemia Treated With Risk-Directed Therapy Based on the Levels of Minimal Residual Disease.
J. Clin. Oncol.
PUBLISHED: 07-23-2014
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BCR-ABL1-like acute lymphoblastic leukemia (ALL) is a recently identified B-cell ALL (B-ALL) subtype with poor outcome that exhibits a gene expression profile similar to BCR-ABL1-positive ALL but lacks the BCR-ABL1 fusion protein. We examined the outcome of children with BCR-ABL1-like ALL treated with risk-directed therapy based on minimal residual disease (MRD) levels during remission induction.
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Infusions of allogeneic natural killer cells as cancer therapy.
Clin. Cancer Res.
PUBLISHED: 07-03-2014
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Natural killer (NK) cells are normal white blood cells capable of killing malignant cells without prior sensitization. Allogeneic NK cell infusions are attractive for cancer therapy because of non-cross-resistant mechanisms of action and minimal overlapping toxicities with standard cancer treatments. Although NK therapy is promising, many obstacles will need to be overcome, including insufficient cell numbers, failure of homing to tumor sites, effector dysfunction, exhaustion, and tumor cell evasion. Capitalizing on the wealth of knowledge generated by recent NK cell biology studies and the advancements in biotechnology, substantial progress has been made recently in improving therapeutic efficiency and reducing side effects. A multipronged strategy is essential, including immunogenetic-based donor selection, refined NK cell bioprocessing, and novel augmentation techniques, to improve NK function and to reduce tumor resistance. Although data from clinical trials are currently limited primarily to hematologic malignancies, broader applications to a wide spectrum of adult and pediatric cancers are under way. The unique properties of human NK cells open up a new arena of novel cell-based immunotherapy against cancers that are resistant to contemporary therapies.
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Tyrosinase inhibitory activity of a glucosylated hydroxystilbene in mouse melan-a melanocytes.
J. Nat. Prod.
PUBLISHED: 06-16-2014
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2,3,5,4'-Tetrahydroxystilbene-2-O-?-D-glucopyranoside (1), isolated from Polygonum multiflorum, is a noncompetitive inhibitor of tyrosinase in cell-free kinetics; it reduced the Vmax values in a dose-dependent manner. Compound 1 inhibited PKA-induced melanogenesis, reduced the protein expression of tyrosinase and its transcription factor, the microphthalmia-associated transcription factor, and lowered the complex formation between tyrosinase and tyrosinase-related protein 1 (TRP-1). Immunofluorescence microscopy revealed no association of tyrosinase with the endoplasmic reticulum or lysosomes, implying the absence of a direct effect of 1 on the maturation process of the enzyme. The antimelanogenic activity of 1 is likely mediated through a noncompetitive inhibition on tyrosinase, down-regulation of the expression of melanogenic proteins, and reduction of tyrosinase/TRP-1 complex formation.
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Identification of microRNA-135b in stool as a potential noninvasive biomarker for colorectal cancer and adenoma.
Clin. Cancer Res.
PUBLISHED: 04-01-2014
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Detecting microRNA (miRNA) in stool is a novel approach for colorectal cancer (CRC) screening. This study aimed to identify stool-based miRNA as noninvasive biomarkers for detection of CRC and adenoma.
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Long-term oncologic outcomes of laparoscopic versus open surgery for rectal cancer: a pooled analysis of 3 randomized controlled trials.
Ann. Surg.
PUBLISHED: 03-29-2014
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To compare long-term oncologic outcomes between laparoscopic and open surgery for rectal cancer and to identify independent predictors of survival.
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Combination of MRI hippocampal volumetry and arterial spin labeling MR perfusion at 3-Tesla improves the efficacy in discriminating Alzheimer's disease from cognitively normal elderly adults.
J. Alzheimers Dis.
PUBLISHED: 03-28-2014
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Structural magnetic resonance imaging has been employed for evaluation of medial temporal atrophy in patients with Alzheimer's disease (AD). Arterial spin labeling (ASL) technique could detect cerebral perfusion abnormalities in AD.
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Protective effects of testosterone on presynaptic terminals against oligomeric ?-amyloid peptide in primary culture of hippocampal neurons.
Biomed Res Int
PUBLISHED: 03-15-2014
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Increasing lines of evidence support that testosterone may have neuroprotective effects. While observational studies reported an association between higher bioavailable testosterone or brain testosterone levels and reduced risk of Alzheimer's disease (AD), there is limited understanding of the underlying neuroprotective mechanisms. Previous studies demonstrated that testosterone could alleviate neurotoxicity induced by ?-amyloid (A?), but these findings mainly focused on neuronal apoptosis. Since synaptic dysfunction and degeneration are early events during the pathogenesis of AD, we aim to investigate the effects of testosterone on oligomeric A?-induced synaptic changes. Our data suggested that exposure of primary cultured hippocampal neurons to oligomeric A? could reduce the length of neurites and decrease the expression of presynaptic proteins including synaptophysin, synaptotagmin, and synapsin-1. A? also disrupted synaptic vesicle recycling and protein folding machinery. Testosterone preserved the integrity of neurites and the expression of presynaptic proteins. It also attenuated A?-induced impairment of synaptic exocytosis. By using letrozole as an aromatase antagonist, we further demonstrated that the effects of testosterone on exocytosis were unlikely to be mediated through the estrogen receptor pathway. Furthermore, we showed that testosterone could attenuate A?-induced reduction of HSP70, which suggests a novel mechanism that links testosterone and its protective function on A?-induced synaptic damage. Taken together, our data provide further evidence on the beneficial effects of testosterone, which may be useful for future drug development for AD.
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Phase I study of the safety and pharmacokinetics of plerixafor in children undergoing a second allogeneic hematopoietic stem cell transplantation for relapsed or refractory leukemia.
Biol. Blood Marrow Transplant.
PUBLISHED: 03-07-2014
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The safety, pharmacokinetics, and biological effect of plerixafor in children as part of a conditioning regimen for chemo-sensitization in allogeneic hematopoietic stem cell transplantation (HSCT) have not been studied. This is a phase I study of plerixafor designed to evaluate its tolerability at dose of .24 mg/kg given intravenously on day -4 (level 1); day -4 and day -3 (level 2); or day -4, day -3, and day -2 (level 3) in combination with fludarabine, thiotepa, melphalan, and rabbit antithymocytic globulin for a second allogeneic HSCT in children with refractory or relapsed leukemia. Immunophenotype analysis was performed on blood and bone marrow before and after plerixafor administration. Twelve patients were enrolled. Plerixafor at all 3 levels was well tolerated without dose-limiting toxicity. Transient gastrointestinal side effects of National Cancer Institute-grade 1 or 2 in severity were the most common adverse events. The area under the concentration-time curve increased proportionally to the dose level. Plerixafor clearance was higher in males and increased linearly with body weight and glomerular filtration rate. The clearance decreased and the elimination half-life increased significantly from dose level 1 to 3 (P < .001). Biologically, the proportion of CXCR4(+) blasts and lymphocytes both in the bone marrow and peripheral blood increased after plerixafor administration.
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Treatment of hepatoblastoma with high-dose chemotherapy and stem cell rescue: the pediatric blood and marrow transplant consortium experience and review of the literature.
J. Pediatr. Hematol. Oncol.
PUBLISHED: 03-01-2014
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Children with high-risk or relapsed hepatoblastoma continue to represent treatment challenges. Multiple case reports have documented the use of high-dose chemotherapy with stem cell rescue (HDC) for this population; however, the efficacy and appropriate use of HDC remains unclear.
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Immunogenicity and safety of intradermal trivalent influenza vaccination in nursing home older adults: a randomized controlled trial.
J Am Med Dir Assoc
PUBLISHED: 02-24-2014
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To compare the immunogenicity and safety between full-dose (15 ?g) intramuscular (i.m.) and full-dose (15 ?g) intradermal (i.d.) immunization of the trivalent influenza vaccine in nursing home older adults.
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Definition of cure in childhood acute myeloid leukemia.
Cancer
PUBLISHED: 02-19-2014
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A better understanding of when cure can be declared in childhood acute myeloid leukemia (AML) would reduce anxiety and improve quality of life of AML survivors. The authors determined the likelihood that patients with AML would maintain long-term remission after the completion of therapy.
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Amyloid beta 1-42 and tau in the cerebrospinal fluid of renal failure patients for the diagnosis of Alzheimer's disease.
J. Nephrol.
PUBLISHED: 01-29-2014
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Cerebrospinal fluid (CSF) A?42, total tau and phosphorylated tau (p-tau) are well-defined diagnostic markers for Alzheimer's disease (AD). There has been no previous report of the use of these markers in the diagnosis of AD in patients with chronic kidney disease (CKD). We would like to report our preliminary findings on these biomarkers in three patients with renal failure. One patient with a clinical diagnosis of AD showed elevated CSF tau, p-tau 181, and decreased A?42 levels, within a similar range as in local Chinese AD patients without renal impairment. The other two delirious patients, who did not have a clinical diagnosis of AD, showed normal CSF biomarkers. We found that the diagnosis of AD with CSF biomarkers appears to be useful in renal failure patients. But our results need to be confirmed in a larger study, comparing these CSF biomarkers in AD vs. non-AD patients with concomitant CKD.
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Validity of the Cantonese Chinese Montreal Cognitive Assessment in Southern Chinese.
Geriatr Gerontol Int
PUBLISHED: 01-25-2014
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The objective of the present study was to investigate the reliability and the validity of the Cantonese Chinese Montreal Cognitive Assessment (MoCA) as a brief screening tool of amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) in Southern Chinese older adults.
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Association between body mass index and cause-specific mortality as well as hospitalization in frail Chinese older adults.
Geriatr Gerontol Int
PUBLISHED: 01-15-2014
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A U-shaped relationship between body mass index (BMI) and all-cause mortality has been reported, but there are few studies examining the association between BMI and cause-specific mortality and hospitalization. We carried out a longitudinal study to examine these associations in Chinese older adults with multiple comorbidities, which could provide a reference for the recommended BMI in this population.
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The relevance of short-range fibers to cognitive efficiency and brain activation in aging and dementia.
PLoS ONE
PUBLISHED: 01-01-2014
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The integrity of structural connectivity in a functional brain network supports the efficiency of neural processing within relevant brain regions. This study aimed to quantitatively investigate the short- and long-range fibers, and their differential roles in the lower cognitive efficiency in aging and dementia. Three groups of healthy young, healthy older adults and patients with Alzheimer's disease (AD) participated in this combined functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) study on prospective memory (PM). Short- and long-range fiber tracts within the PM task engaged brain networks were generated. The correlation between the fMRI signal change, PM performance and the DTI characters were calculated. FMRI results showed that the PM-specific frontal activations in three groups were distributed hierarchically along the rostrocaudal axis in the frontal lobe. In an overall PM condition generally activated brain network among the three groups, tractography was used to generate the short-range fibers, and they were found impaired in both healthy older adults and AD patients. However, the long-range fiber tracts were only impaired in AD. Additionally, the mean diffusivity (MD) of short-range but not long-range fibers was positively correlated with fMRI signal change and negatively correlated with the efficiency of PM performance. This study suggests that the disintegrity of short-range fibers may contribute more to the lower cognitive efficiency and higher compensatory brain activation in healthy older adults and more in AD patients.
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Vascular risk factors and mild cognitive impairment in the elderly population in Southwest China.
Am J Alzheimers Dis Other Demen
PUBLISHED: 01-01-2014
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Increasing evidence has demonstrated that vascular risk factors (VRFs) contribute to cognitive impairment in the elderly population. Prevention and administration of VRFs can be a vital strategy for delaying cognitive impairment. This study aimed to determine the impact of VRFs on cognitive function of the aged people from Chongqing, Southwest China.
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Modulation of NKG2D ligand expression and metastasis in tumors by spironolactone via RXR? activation.
J. Exp. Med.
PUBLISHED: 11-04-2013
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Tumor metastasis and lack of NKG2D ligand (NKG2DL) expression are associated with poor prognosis in patients with colon cancer. Here, we found that spironolactone (SPIR), an FDA-approved diuretic drug with a long-term safety profile, can up-regulate NKG2DL expression in multiple colon cancer cell lines by activating the ATM-Chk2-mediated checkpoint pathway, which in turn enhances tumor elimination by natural killer cells. SPIR can also up-regulate the expression of metastasis-suppressor genes TIMP2 and TIMP3, thereby reducing tumor cell invasiveness. Although SPIR is an aldosterone antagonist, its antitumor effects are independent of the mineralocorticoid receptor pathway. By screening the human nuclear hormone receptor siRNA library, we identified retinoid X receptor ? (RXR?) instead as being indispensable for the antitumor functions of SPIR. Collectively, our results strongly support the use of SPIR or other RXR? agonists with minimal side effects for colon cancer prevention and therapy.
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Corneal shapes of Chinese emmetropes and myopic astigmats aged 10 to 45 years.
Optom Vis Sci
PUBLISHED: 10-01-2013
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Myopia and astigmatism are highly prevalent in the Hong Kong Chinese. This study aimed to determine the effects of age and myopic astigmatism (MA) on the corneal shape factors in the Hong Kong Chinese.
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Prospective detection of respiratory pathogens in symptomatic children with cancer.
Pediatr. Infect. Dis. J.
PUBLISHED: 09-21-2013
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: The data on human rhinovirus, coronavirus, bocavirus, metapneumovirus, Chlamydophila pneumoniae, Mycoplasma pneumoniae and Bordetella pertussis infections in children with cancer is limited.
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Effect of donor KIR2DL1 allelic polymorphism on the outcome of pediatric allogeneic hematopoietic stem-cell transplantation.
J. Clin. Oncol.
PUBLISHED: 09-16-2013
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Killer-cell immunoglobulin-like receptors (KIRs) that regulate natural-killer cells are highly polymorphic. Some KIR2DL1 alleles encode receptors that have stronger signaling function than others. We tested the hypothesis that the clinical outcomes of allogeneic hematopoietic stem-cell transplantation (HSCT) could be affected by donor KIR2DL1 polymorphism.
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Effectiveness of Influenza Vaccination in Institutionalized Older Adults: A Systematic Review.
J Am Med Dir Assoc
PUBLISHED: 09-02-2013
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Influenza infection is common among institutionalized older adults. Many nonrandomized observational studies on influenza vaccination suggested that it could reduce influenza-related hospitalizations and mortality in institutionalized older adults. Criticism regarding the effectiveness of influenza vaccine estimated by nonrandomized observational studies include the frailty selection bias and use of nonspecific outcome, such as all-cause mortality.
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A diet rich in high-glucoraphanin broccoli interacts with genotype to reduce discordance in plasma metabolite profiles by modulating mitochondrial function.
Am. J. Clin. Nutr.
PUBLISHED: 08-22-2013
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Observational and experimental studies suggest that diets rich in cruciferous vegetables and glucosinolates may reduce the risk of cancer and cardiovascular disease (CVD).
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Synthesis and structural characterization of base-stabilized oligomeric heterovinylidenes.
Inorg Chem
PUBLISHED: 08-08-2013
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Metalation of the (iminophosphoranyl)phosphine PPh2CH2(PPh2?NSiMe3) (1) with an equimolar amount of n-BuLi afforded the monolithium salt [Li{CH(PPh2)(PPh2?NSiMe3)}(THF)2] (2). The reaction of 2 with GeCl2·1,4-dioxane has led to the formation of a germavinylene moiety, which trimerized to form a new heterocyclic cage compound, [{(PPh2?NSiMe3)(PPh2)C?Ge:}{(PPh2?NSiMe3)(PPh2)C}2Ge?Ge:] (3). A similar reaction of the lithium methanide complex 2 with SnCl2 afforded the stannavinylidene moiety, which underwent a "head-to-tail" cycloaddition to form a stable 1,3-distannacyclobutane, 4. A trapping reaction of 4 with diiron nonacarbonyl gave the novel iron stannavinylidene complex 5. The solid-state structure analysis of 5 reveals that it contains two stannavinylidene moieties bonded in a Sn-P "head-to-tail" fashion, with one of the tin(II) centers coordinating to a Fe(CO)4 moiety. The X-ray structures of 2-5 have been determined by X-ray crystallography. In addition, the dynamic behavior of 5 has been studied by means of variable-temperature (31)P and (119)Sn NMR spectroscopy.
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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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Multiplex and genome-wide analyses reveal distinctive properties of KIR+ and CD56+ T cells in human blood.
J. Immunol.
PUBLISHED: 07-15-2013
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Killer cell Ig-like receptors (KIRs) on NK cells have been linked to a wide spectrum of health conditions such as chronic infections, autoimmune diseases, pregnancy complications, cancers, and transplant failures. A small subset of effector memory T cells also expresses KIRs. In this study, we use modern analytic tools including genome-wide and multiplex molecular, phenotypic, and functional assays to characterize the KIR(+) T cells in human blood. We find that KIR(+) T cells primarily reside in the CD56(+) T population that is distinctively DNAM-1(high) with a genome-wide quiescent transcriptome, short telomere, and limited TCR excision circles. During CMV reactivation in bone marrow transplant recipients, KIR(+)CD56(+) T cells rapidly expanded in real-time but not KIR(+)CD56(-) T cells or KIR(+) NK cells. In CMV(+) asymptomatic donors, as much as 50% of CD56(+) T cells are KIR(+), and most are distinguishably KIR2DL2/3(+)NKG2C(+)CD57(+). Functionally, the KIR(+)CD56(+) T cell subset lyses cancer cells and CMVpp65-pulsed target cells in a dual KIR-dependent and TCR-dependent manner. Analysis of metabolic transcriptome confirms the immunological memory status of KIR(+)CD56(+) T cells in contrast to KIR(-)CD56(+) T cells that are more active in energy metabolism and effector differentiation. KIR(-)CD56(+) T cells have >25-fold higher level of expression of RORC than the KIR(+) counterpart and are a previously unknown producer of IL-13 rather than IL-17 in multiplex cytokine arrays. Our data provide fundamental insights into KIR(+) T cells biologically and clinically.
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Label-free detection of endocrine disrupting chemicals by integrating a competitive binding assay with a piezoelectric ceramic resonator.
Biosens Bioelectron
PUBLISHED: 07-11-2013
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A piezoelectric biosensor for detection of endocrine disrupting chemicals (EDCs) was developed by incorporating chemical/biochemical recognition elements on the ceramic resonator surface for competitive binding assays. A facile electrodeposition was employed to modify the sensor surface with Au nanoparticles, which increased the surface area and enhanced the binding capacity of the immobilized probes. Thiol-labeled long chain hydrocarbon with bisphenol A (BPA) as head group was synthesized and self-assembled on the Au nanoparticle surface as the sensing probes, which showed a linear response upon the binding of estrogen receptor (ER-?) ranging from 1 to 30nM. Detection of estrone, 17?-estradiol and BPA was achieved by integrating a competitive binding assay with the piezoelectric sensor. In this detection scheme, different concentrations of EDCs were incubated with 30nM of ER-?, and the un-bounded ER-? in the solution was captured by the probes immobilized on the ceramic resonator, which resulted in the frequency changes for different EDCs. The biosensor assay exhibited a linear response to EDCs with a low detection limit of 2.4-2.9nM (S/N=3), and required only a small volume of sample (1.5µl) with the assay time of 2h. The performance of the biosensor assay was also evaluated for rapid and facile determination of EDCs of environmental relevant concentrations in drinking water and seawater, and the recovery rate was in the range between 94.7% and 109.8%.
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Validation study of Charlson Comorbidity Index in predicting mortality in Chinese older adults.
Geriatr Gerontol Int
PUBLISHED: 06-30-2013
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The Charlson Comorbidity Index (CCI) is commonly studied for predicting mortality, but there is no validation study of it in Chinese older adults. The objective of the present study was to validate the use of CCI in Chinese older adults for predicting mortality.
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A dinuclear ruthenium catalyst with a confined cavity: selectivity in the addition of aliphatic carboxylic acids to phenylacetylene.
Chem. Commun. (Camb.)
PUBLISHED: 05-15-2013
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A dinuclear ruthenium catalyst with a rigid anthracene spacer shows excellent regio- and stereo-selectivity in the atom-economic addition of aliphatic carboxylic acids to phenylacetylene, producing exclusively anti-Markovnikov enol-esters with high E/Z ratios of the isomers.
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Metabolic changes in the anterior and posterior cingulate cortices of the normal aging brain: proton magnetic resonance spectroscopy study at 3 T.
Age (Dordr)
PUBLISHED: 05-14-2013
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Magnetic resonance spectroscopy (MRS) can explore aging at a molecular level. In this study, we investigated the relationships between regional concentrations of metabolites (such as choline, creatine, myo-inositol, and N-acetyl-aspartate) and normal aging in 30 cognitively normal subjects (15 women and 15 men, age range 22-82, mean?=?49.9?±?18.3 years) using quantitative proton magnetic resonance spectroscopy. All MR scans were performed using a 3 T scanner. Point resolved spectroscopy was used as the volume selection method for the region-of-interest and the excitation method for water suppression. Single voxel spectroscopy with short echo time of 39 ms and repetition time of 2,000 ms was employed. Single voxels were placed in the limbic regions, i.e., anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and left and right hippocampi. Cerebrospinal fluid normalization and T1 and T2 correction factors were implemented in the calculation of absolute metabolite concentrations. A standardized T1W 3D volumetric fast field echo and axial T2-weighted fast spin-echo images were also acquired. Our results showed significant positive correlation of choline (r?=?0.545, p?=?0.002), creatine (r?=?0.571, p?=?0.001), and N-acetyl-aspartate (r?=?0.674, p?
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Estimating daily and diurnal variations of illicit drug use in Hong Kong: A pilot study of using wastewater analysis in an Asian metropolitan city.
Forensic Sci. Int.
PUBLISHED: 05-06-2013
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The measurement of illicit drug metabolites in raw wastewater is increasingly being adopted as an approach to objectively monitor population-level drug use, and is an effective complement to traditional epidemiological methods. As such, it has been widely applied in western countries. In this study, we utilised this approach to assess drug use patterns over nine days during April 2011 in Hong Kong. Raw wastewater samples were collected from the largest wastewater treatment plant serving a community of approximately 3.5 million people and analysed for excreted drug residues including cocaine, ketamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and key metabolites using liquid chromatography coupled with tandem mass spectrometry. The overall drug use pattern determined by wastewater analysis was consistent with that have seen amongst people coming into contact with services in relation to substance use; among our target drugs, ketamine (estimated consumption: 1400-1600mg/day/1000 people) was the predominant drug followed by methamphetamine (180-200mg/day/1000 people), cocaine (160-180mg/day/1000 people) and MDMA (not detected). The levels of these drugs were relatively steady throughout the monitoring period. Analysing samples at higher temporal resolution provided data on diurnal variations of drug residue loads. Elevated ratios of cocaine to benzoylecgonine were identified unexpectedly in three samples during the evening and night, providing evidence for potential dumping events of cocaine. This study provides the first application of wastewater analysis to quantitatively evaluate daily drug use in an Asian metropolitan community. Our data reinforces the benefit of wastewater monitoring to health and law enforcement authorities for strategic planning and evaluation of drug intervention strategies.
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Pharmaceuticals in tap water: human health risk assessment and proposed monitoring framework in China.
Environ. Health Perspect.
PUBLISHED: 05-01-2013
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Pharmaceuticals are known to contaminate tap water worldwide, but the relevant human health risks have not been assessed in China.
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Community end-of-life care among Chinese older adults living in nursing homes.
Geriatr Gerontol Int
PUBLISHED: 04-04-2013
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AIM: The aim of the present study was to investigate the preference and willingness-to-pay (WTP) of older Chinese adults for community end-of-life care in a nursing home rather than a hospital. METHODS: A total of 1540 older Chinese adults from 140 nursing homes were interviewed. Four hypothetical questions were asked to explore their preferences for end-of-life care. Using a discrete choice approach, specific questions explored acceptable trade-offs between three attributes: availability of doctors onsite, attitude of the care staff and additional cost of care per month. RESULTS: Approximately 35% of respondents preferred end-of-life care in the nursing home, whereas 23% of them would consider it in a better nursing home. A good attitude of staff was the most important attribute of the care site. Respondents were willing to pay an extra cost of US$5 (HK$39) per month for more coverage of doctors time, and US$49 (HK$379) for a better attitude of staff in the nursing home. The marginal WTP for both more coverage of doctors time and better attitude of staff amounted to US$54 (HK$418). Respondents on government subsidy valued the cost attribute more highly, as expected, validating the hypothesis that those respondents would be less willing to pay an additional cost for end-of-life care. CONCLUSIONS: Older Chinese adults living in nursing homes are willing to pay an additional fee for community end-of-life care services in nursing homes. Both the availability of the doctor and attitudes of nursing home staff are important, with the most important attribute being the staff attitudes. Geriatr Gerontol Int 2013; ??: ??-??.
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Synthesis of hetero-binuclear complexes from bisgermavinylidene.
Inorg Chem
PUBLISHED: 03-25-2013
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Bisgermavinylidene [(Me3SiN?PPh2)2C?Ge?Ge?C(PPh2?NSiMe3)2] (1) has been used as a source of unstable germavinylidene for the synthesis of a series of heterobinuclear complexes. The reaction of 1 with stoichiometric amounts of transition metal chlorides MCl2 (M = Mn, Fe) yielded [(Me3SiN?PPh2)2(GeCl)CMn(?-Cl)]2 (2) and [(Me3SiN?PPh2)2(GeCl)CFeCl] (3), respectively. Treatment of 1 with Me3SiN3 gave the [2 + 3] cycloaddition product [(Me3SiN?PPh2)2CGeN(SiMe3)N?N] (4). While similar reaction of 1 with ((n)Bu)3SnN3 ((n)Bu = n-butyl) and water-borane adduct H2O ? B(C6F5)3 afforded the 1,2-addition products [(Me3SiN?PPh2){((n)Bu)3Sn}CPPh2NSiMe3GeN3] (5) and [HC(PPh2?NSiMe3)2Ge(OH)B(C6F5)3] (6), respectively. The results suggested that the germanium-carbon bond in germavinylidene is capable of forming addition reaction products. The X-ray structures of 2-6 have been determined.
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Delayed recovery from ertapenem induced encephalopathy: case-report and a possible mechanism.
Int J Clin Pharm
PUBLISHED: 03-16-2013
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The objective of this case report is to report a patient with moderate renal impairment who developed ertapenem-induced encephalopathy with delayed recovery of up to 2 weeks despite receiving and appropriately adjusted dosage of ertapenem. The patient was managed conservatively with full recovery. Carbapenem related neurotoxicity most commonly manifests as seizure with an estimated incidence of 3 %. There are increasing reports of encephalopathy being related to ertapenem and most commonly subsides within days and extended recovery of up to 2 weeks have only been reported in patients with end-stage renal failure.
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Laparoscopic-assisted versus open total mesorectal excision with anal sphincter preservation for mid and low rectal cancer: a prospective, randomized trial.
Surg Endosc
PUBLISHED: 03-02-2013
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This single-center, prospective, randomized trial was designed to compare the short-term clinical outcome between laparoscopic-assisted versus open total mesorectal excision (TME) with anal sphincter preservation (ASP) in patients with mid and low rectal cancer. Long-term morbidity and survival data also were recorded and compared between the two groups.
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Prospective evaluation for respiratory pathogens in children with sickle cell disease and acute respiratory illness.
Pediatr Blood Cancer
PUBLISHED: 02-28-2013
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Human rhinovirus (HRV), human coronavirus (hCoV), human bocavirus (hBoV), and human metapneumovirus (hMPV) infections in children with sickle cell disease have not been well studied.
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Outcomes of allogeneic hematopoietic cell transplantation in patients with dyskeratosis congenita.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-28-2013
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We describe outcomes after allogeneic transplantation in 34 patients with dyskeratosis congenita who underwent transplantation between 1981 and 2009. The median age at transplantation was 13 years (range, 2 to 35). Approximately 50% of transplantations were from related donors. Bone marrow was the predominant source of stem cells (24 of 34). The day-28 probability of neutrophil recovery was 73% and the day-100 platelet recovery was 72%. The day-100 probability of grade II to IV acute GVHD and the 3-year probability of chronic graft-versus-host disease were 24% and 37%, respectively. The 10-year probability of survival was 30%; 14 patients were alive at last follow-up. Ten deaths occurred within 4 months from transplantation because of graft failure (n = 6) or other transplantation-related complications; 9 of these patients had undergone transplantation from mismatched related or from unrelated donors. Another 10 deaths occurred after 4 months; 6 of them occurred more than 5 years after transplantation, and 4 of these were attributed to pulmonary failure. Transplantation regimen intensity and transplantations from mismatched related or unrelated donors were associated with early mortality. Transplantation of grafts from HLA-matched siblings with cyclophosphamide-containing nonradiation regimens was associated with early low toxicity. Late mortality was attributed mainly to pulmonary complications and likely related to the underlying disease.
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Efficacy of trivalent seasonal influenza vaccination in reducing mortality and hospitalization in chinese nursing home older adults.
J Am Med Dir Assoc
PUBLISHED: 02-27-2013
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To examine the clinical efficacy of the trivalent seasonal influenza vaccination among Chinese older adults residing in a nursing home.
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Quality of life after laparoscopic vs open sphincter-preserving resection for rectal cancer.
World J. Gastroenterol.
PUBLISHED: 02-25-2013
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To compare quality of life (QoL) outcomes in Chinese patients after curative laparoscopic vs open surgery for rectal cancer.
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Ex vivo activation of CD56(+) immune cells that eradicate neuroblastoma.
Cancer Res.
PUBLISHED: 02-25-2013
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Despite the use of intensive contemporary multimodal therapy, the overall survival of patients with high-risk neuroblastoma is still less than 50%. Therefore, immunotherapy without cross-resistance and overlapping toxicity has been proposed. In this study, we report the development of a novel strategy to specifically activate and expand human CD56(+) (NCAM1) natural killer (NK) immune cells from normal donors and patients with neuroblastoma. Enriched CD56(+) cells from peripheral blood were mixed with CD56(-) fraction at 1:1 ratio and cultured in the presence of OKT3, interleukin (IL)-2, and -15 for five days and then without OKT3 for 16 more days. The final products contained more than 90% CD56(+) cells and could kill neuroblastoma cells effectively that were originally highly resistant to nonprocessed NK cells. Mechanistically, cytolysis of neuroblastoma was mediated through natural cytotoxicity receptor (NCR), DNAX accessory molecule-1 (DNAM-1; CD226), perforin, and granzyme B. Successful clinical scale-up in a good manufacturing practices (GMP)-compliant bioreactor yielded effector cells that in a neuroblastoma xenograft model slowed tumor growth and extended survival without GVHD. Investigation of CD56(+) cells from patients with neuroblastoma revealed a similar postactivation phenotype and lytic activity. Our findings establish a novel and clinically expedient strategy to generate allogeneic or autologous CD56(+) cells that are highly cytotoxic against neuroblastoma with minimal risk of GVHD.
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Long-term outcome and evaluation of organ function in pediatric patients undergoing haploidentical and matched related hematopoietic cell transplantation for sickle cell disease.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-10-2013
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HLA-matched related donor (MRD) hematopoietic stem cell transplantation (HSCT) is a well-established therapy for patients with sickle cell disease (SCD); however, experience using alternative donors, including haploidentical donors, in HSCT for SCD is limited. We report the long-term outcomes of 22 pediatric patients who underwent related donor HSCT for SCD at St. Jude Childrens Research Hospital, either a myeloablative sibling MRD HSCT (n = 14) or reduced-intensity parental haploidentical donor HSCT (n = 8). The median patient age was 11.0 ± 3.9 years in the MRD graft recipients and 9.0 ± 5.0 years in the haploidentical donor graft recipients. The median follow-up was 9.0 ± 2.3 years, with an overall survival (OS) of 93% and a recurrence/graft failure rate of 0%, for the MRD cohort and 7.4 ± 2.4 years, with an OS of 75%, disease-free survival of 38%, and disease recurrence of 38%, for the haploidentical donor cohort. We report the long-term hematologic response and organ function in patients undergoing MRD or haploidentical donor HSCT for severe SCD. Our data demonstrate long-term hematologic improvements after HSCT with sustained engraftment, and confirm that HSCT offers long-term protection from common complications of SCD, including stroke, pulmonary hypertension, acute chest, and nephropathy, regardless of donor source.
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Use of second-line therapies for management of massive primary postpartum hemorrhage.
Int J Gynaecol Obstet
PUBLISHED: 02-04-2013
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To determine rates of use and success of second-line therapies for massive primary postpartum hemorrhage (PPH).
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Acupuncture transcutaneous electrical nerve stimulation reduces discomfort associated with barostat-induced rectal distension: a randomized-controlled study.
World J. Gastroenterol.
PUBLISHED: 02-02-2013
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To explore the effectiveness of acupuncture transcutaneous electrical nerve stimulation (Acu-TENS), a non-invasive modality in reduction of rectal discomfort during barostat-induced rectal distension.
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Detection of cancer biomarkers by piezoelectric biosensor using PZT ceramic resonator as the transducer.
Biosens Bioelectron
PUBLISHED: 01-28-2013
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A novel piezoelectric biosensor using lead titanate zirconate (PZT) ceramic resonator as transducer was developed for label-free, cost-effective, and direct detection of cancer biomarkers. We designed a dual sensing scheme where two ceramic resonators were connected in parallel, in which one resonator was used as the sensing unit and the other as the control unit, in order to minimize environment influences including temperature fluctuation and to achieve the required frequency stability for biosensing applications. Detection of selected cancer biomarkers, such as prostate specific antigen (PSA) and ?-fetoprotein (AFP) was carried out to evaluate the performance of the biosensor. The device showed high sensitivity (0.25 ng/ml) and fast detection (within 30 min) with small amount of sample (1 ?l), which is compatible to that required by clinical measurements. The results also showed that the ceramic resonator-based piezoelectric biosensor platform could be utilized with different chemical interfaces, and the miniaturized size of the ceramic resonators makes it suitable for fabricating sensor arrays for multiplex detection.
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Photodynamic therapy induced cell death of hormone insensitive prostate cancer PC-3 cells with autophagic characteristics.
Photodiagnosis Photodyn Ther
PUBLISHED: 01-13-2013
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The introduction of photodynamic therapy (PDT) to the treatment of advanced prostate cancer can accomplish the eradication of local neoplasm and distant metastases with minimized damage to the adjacent structures. The evidence of PDT efficacy for androgen-refractory prostate cancer will be especially meaningful for the patients resistant to hormone therapy.
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The Ecm11-Gmc2 complex promotes synaptonemal complex formation through assembly of transverse filaments in budding yeast.
PLoS Genet.
PUBLISHED: 01-10-2013
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During meiosis, homologous chromosomes pair at close proximity to form the synaptonemal complex (SC). This association is mediated by transverse filament proteins that hold the axes of homologous chromosomes together along their entire length. Transverse filament proteins are highly aggregative and can form an aberrant aggregate called the polycomplex that is unassociated with chromosomes. Here, we show that the Ecm11-Gmc2 complex is a novel SC component, functioning to facilitate assembly of the yeast transverse filament protein, Zip1. Ecm11 and Gmc2 initially localize to the synapsis initiation sites, then throughout the synapsed regions of paired homologous chromosomes. The absence of either Ecm11 or Gmc2 substantially compromises the chromosomal assembly of Zip1 as well as polycomplex formation, indicating that the complex is required for extensive Zip1 polymerization. We also show that Ecm11 is SUMOylated in a Gmc2-dependent manner. Remarkably, in the unSUMOylatable ecm11 mutant, assembly of chromosomal Zip1 remained compromised while polycomplex formation became frequent. We propose that the Ecm11-Gmc2 complex facilitates the assembly of Zip1 and that SUMOylation of Ecm11 is critical for ensuring chromosomal assembly of Zip1, thus suppressing polycomplex formation.
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Clinical significance of minimal residual disease in patients with acute leukaemia undergoing haematopoietic stem cell transplantation.
Br. J. Haematol.
PUBLISHED: 01-04-2013
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In patients with acute leukaemia, the relative risk of relapse influences the choice between chemotherapy and haematopoietic stem cell transplantation (HSCT). The demonstration that minimal residual disease (MRD) is the strongest overall prognostic indicator and can identify patients who are unlikely to be cured by standard chemotherapy has added a powerful new factor to consider when making this decision. There is substantial data indicating that the likelihood of relapse after transplant is directly correlated with levels of MRD before transplant. This knowledge can be used to adjust the timing of HSCT, and guide the selection of donor, conditioning regimen, and post-HSCT strategies to maximize the graft-versus-leukaemia effect. Because MRD emerging post-transplant carries a dire prognosis, its detection can trigger withdrawal of immunosuppression, additional cellular and molecular therapies, or preparations for a second HSCT. Although it is not yet clear whether any of these actions will significantly improve outcome, it is likely that they will be most effective for patients with a relatively low tumour burden, who can be identified only through MRD testing. In this article, we review the clinical significance of MRD in the context of autologous and allogeneic HSCT.
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Direct and indirect control of the initiation of meiotic recombination by DNA damage checkpoint mechanisms in budding yeast.
PLoS ONE
PUBLISHED: 01-01-2013
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Meiotic recombination plays an essential role in the proper segregation of chromosomes at meiosis I in many sexually reproducing organisms. Meiotic recombination is initiated by the scheduled formation of genome-wide DNA double-strand breaks (DSBs). The timing of DSB formation is strictly controlled because unscheduled DSB formation is detrimental to genome integrity. Here, we investigated the role of DNA damage checkpoint mechanisms in the control of meiotic DSB formation using budding yeast. By using recombination defective mutants in which meiotic DSBs are not repaired, the effect of DNA damage checkpoint mutations on DSB formation was evaluated. The Tel1 (ATM) pathway mainly responds to unresected DSB ends, thus the sae2 mutant background in which DSB ends remain intact was employed. On the other hand, the Mec1 (ATR) pathway is primarily used when DSB ends are resected, thus the rad51 dmc1 double mutant background was employed in which highly resected DSBs accumulate. In order to separate the effect caused by unscheduled cell cycle progression, which is often associated with DNA damage checkpoint defects, we also employed the ndt80 mutation which permanently arrests the meiotic cell cycle at prophase I. In the absence of Tel1, DSB formation was reduced in larger chromosomes (IV, VII, II and XI) whereas no significant reduction was found in smaller chromosomes (III and VI). On the other hand, the absence of Rad17 (a critical component of the ATR pathway) lead to an increase in DSB formation (chromosomes VII and II were tested). We propose that, within prophase I, the Tel1 pathway facilitates DSB formation, especially in bigger chromosomes, while the Mec1 pathway negatively regulates DSB formation. We also identified prophase I exit, which is under the control of the DNA damage checkpoint machinery, to be a critical event associated with down-regulating meiotic DSB formation.
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Novel attributes of Hed1 affect dynamics and activity of the Rad51 presynaptic filament during meiotic recombination.
J. Biol. Chem.
PUBLISHED: 11-24-2011
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During meiosis, recombination events that occur between homologous chromosomes help prepare the chromosome pairs for proper disjunction in meiosis I. The concurrent action of the Rad51 and Dmc1 recombinases is necessary for an interhomolog bias. Notably, the activity of Rad51 is tightly controlled, so as to minimize the use of the sister chromatid as recombination partner. We demonstrated recently that Hed1, a meiosis-specific protein in Saccharomyces cerevisiae, restricts the access of the recombinase accessory factor Rad54 to presynaptic filaments of Rad51. We now show that Hed1 undergoes self-association in a Rad51-dependent manner and binds ssDNA. We also find a strong stabilizing effect of Hed1 on the Rad51 presynaptic filament. Biochemical and genetic analyses of mutants indicate that these Hed1 attributes are germane for its recombination regulatory and Rad51 presynaptic filament stabilization functions. Our results shed light on the mechanism of action of Hed1 in meiotic recombination control.
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Single nucleotide polymorphisms upstream from the ?-carotene 15,15-monoxygenase gene influence provitamin A conversion efficiency in female volunteers.
J. Nutr.
PUBLISHED: 11-23-2011
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?-Carotene, the most abundant provitamin A carotenoid in the diet, is converted to retinal by ?-carotene 15,15-monoxygenase (BCMO1). However, ?-carotene absorption and conversion into retinal is extremely variable among individuals, with proportions of low responders to dietary ?-carotene as high as 45%. Recently, 2 common nonsynonymous single nucleotide polymorphisms (SNPs) within the BCMO1 coding region (R267S; rs12934922 and A379V; rs7501331) revealed reduced catalytic activity, confirming that genetic variations contribute to the low responder phenotype. Because 4 SNPs 5 upstream from the BCMO1 gene were recently shown to affect circulating carotenoid concentrations, the current study aimed to investigate the effects of these SNPs on ?-carotene conversion efficiency. Three of the 4 polymorphisms (rs6420424, rs11645428, and rs6564851) reduced the catalytic activity of BCMO1 in female volunteers by 59, 51, and 48%, respectively. The TG-rich lipoprotein fraction retinyl palmitate:?-carotene ratio was negatively correlated with the G allele of rs11645428 (r = -0.44; P = 0.018), whereas it was positively correlated with the G allele of rs6420424 (r = 0.53; P = 0.004) and the T allele of rs6564851 (r = 0.41; P = 0.028). Furthermore, large inter-ethnic variations in frequency of affected alleles were detected, with frequencies varying from 43 to 84% (rs6420424), 52 to 100% (rs11645428), and 19 to 67% (rs6564851). In summary, a range of SNPs can influence the effectiveness of using plant-based provitamin A carotenoids to increase vitamin A status in at-risk population groups and this effect may vary depending on ethnic origin.
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Second malignant neoplasms in childhood cancer survivors in a tertiary paediatric oncology centre in Hong Kong, China.
Chin. Med. J.
PUBLISHED: 11-16-2011
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Childhood cancer survivors were at risk of development of second malignant neoplasms. The aim of this study is to evaluate the incidence, risk factors and outcome of second malignant neoplasms in childhood cancer survivors in a tertiary paediatric oncology centre in Hong Kong, China.
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Longitudinal analysis of antibody response to immunization in paediatric survivors after allogeneic haematopoietic stem cell transplantation.
Br. J. Haematol.
PUBLISHED: 10-24-2011
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The long-term antibody responses to re-immunization in recipients of allogeneic haematopoietic stem cell transplantation (allo-HSCT) have not been well studied. We prospectively and longitudinally evaluated the antibody responses to eight vaccine antigens (diphtheria, tetanus, pertussis, measles, mumps, rubella, hepatitis B, and poliovirus) and assessed the factors associated with negative titres in 210 allo-HSCT recipients at St. Jude Childrens Research Hospital. Antibody responses lasting for more than 5 years after immunization were observed in most patients for tetanus (95.7%), rubella (92.3%), poliovirus (97.9%), and, in diphtheria-tetanus-acellular pertussis (DTaP) recipients, diphtheria (100%). However, responses to pertussis (25.0%), measles (66.7%), mumps (61.5%), hepatitis B (72.9%), and diphtheria in tetanus-diphtheria (Td) recipients (48.6%) were less favourable, with either only transient antibody responses or persistently negative titres. Factors associated with vaccine failure were older age at immunization; lower CD3, CD4 or CD19 counts; higher IgM concentrations; positive recipient cytomegalovirus serology; negative titres before immunization; acute or chronic graft-versus-host disease; and radiation during preconditioning. These response patterns and clinical factors can be used to formulate re-immunization and monitoring strategies. Patients at risk for vaccine failure should have long-term follow-up; those with loss of antibody response or no seroconversion should receive booster immunizations.
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Synthesis and structural characterization of a tin analogue of allene.
Inorg Chem
PUBLISHED: 10-14-2011
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The reaction of [MgC(PPh(2)?S)(2)(THF)](2) (1; THF = tetrahydrofuran) with 1 equiv of SnCl(4) in THF afforded a novel tin analogue of allene [Sn{C(PPh(2)?S)(2)}(2)] (2). The structure of compound 2 has been characterized by X-ray crystallography and NMR spectroscopy.
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Quality assurance of nuchal translucency for prenatal fetal Down syndrome screening.
J. Matern. Fetal. Neonatal. Med.
PUBLISHED: 10-04-2011
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To assess the quality of nuchal translucency, (NT) measurements were performed at four public institutions performing routine first trimester combined prenatal screening for Down syndrome.
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Intrapartum translabial ultrasound demonstration of face presentation during first stage of labor.
J. Obstet. Gynaecol. Res.
PUBLISHED: 09-28-2011
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We report an unusual case in which sonographic diagnosis of face presentation was made by translabial ultrasound examination during the first stage of labor. In a multigravida, induction of labor was performed at 39 weeks gestation for suspected small-for-gestational age. The diagnosis of face presentation was confirmed by the use of intrapartum translabial ultrasound examination. In face presentation, the orbits and nasal bridge are shown in the center of the presenting part at the mid-sagittal plane. Emergency cesarean delivery was performed for labor dystocia. Here we discuss the merits and limitations of transabdominal, transvaginal and translabial ultrasound examinations in assisting clinical diagnosis of non-vertex malpresentation. We propose the use of intrapartum translabial scan in documentation, counseling and education in case of unusual non-vertex malpresentation.
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Comparing administration of nutrition support with prescribed dose.
J Pediatr Oncol Nurs
PUBLISHED: 09-28-2011
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The aim of this study was to evaluate whether pediatric bone marrow transplant (BMT) patients receive the prescribed dose of nutrition support (NS). Data were obtained from electronic and paper charts at St. Jude Childrens Research Hospital. The amount of NS received was compared with the amount prescribed. Data were collected on 32 patients for 63 hospital stays in which NS was administered. The mean percentage of nutrition prescription met and percentage of total estimated energy met were 69% and 72%, respectively. Allogeneic BMT patients received significantly more of their nutrition prescription (92%) than autologous BMT patients did (54%, P < .01). Malnourished patients were significantly more likely to receive the full dose of NS than patients who were considered nourished or obese (P < .05). This study showed that patients who were most in need of NS were more likely to receive the full dose.
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Detection of miR-92a and miR-21 in stool samples as potential screening biomarkers for colorectal cancer and polyps.
Gut
PUBLISHED: 09-19-2011
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The detection of molecular markers in stool samples is a potential strategy for colorectal cancer (CRC) screening. This study evaluated the feasibility of detecting miR-21 and miR-92a in stool samples of patients with CRC or polyps.
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Continuous use of antipsychotics and its association with mortality and hospitalization in institutionalized Chinese older adults: an 18-month prospective cohort study.
Int Psychogeriatr
PUBLISHED: 09-09-2011
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Previous meta-analyses have suggested that antipsychotics are associated with increased mortality in dementia patients with behavioral and psychological symptoms (BPSD). Subsequent observational studies, however, have produced conflicting results. In view of this controversy and the lack of any suitable pharmacological alternative for BPSD, this study aimed to investigate the relationship between continuous use of antipsychotics and mortality as well as hospitalizations in Chinese older adults with BPSD residing in nursing homes.
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Emergency laparoscopic-assisted right hemicolectomy: can we achieve outcomes similar to elective operation?
J Laparoendosc Adv Surg Tech A
PUBLISHED: 08-22-2011
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The aim of this study was to compare short-term clinical outcomes of elective and emergency laparoscopic-assisted right hemicolectomy. Between January 2005 and December 2009, 181 patients had laparoscopic-assisted right hemicolectomy performed at our institute (148 elective and 33 emergency cases). The demographic data, operative details, and short-term outcomes were collected. There were 104 men and 77 women. The median age was 69 years (range, 22-88 years). The demographic data of the 2 groups were similar except the patients were younger in the emergency surgery group (60 vs. 69 years; P=.02). The operating time of the emergency group was significantly longer then the elective group (165 vs. 150 minutes; P<.001) but the intraoperative blood loss was similar. The postoperative complication and recovery were similar between the 2 groups. In selected clinical settings, emergency laparoscopic-assisted right hemicolectomy can be safely performed without worsening the clinical outcomes.
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Use of NK cell activity in cure by transplant.
Br. J. Haematol.
PUBLISHED: 08-04-2011
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Analogous to T cells, Natural Killer (NK) cells may facilitate engraftment, combat infection, and control cancer in bone marrow or haematopoietic stem cell transplantation (HSCT); however, NK cells do not cause graft-versus-host disease. Killer immunoglobulin-like receptors (KIRs) regulate NK cell function, and recent data suggest that KIR is as important as its ligand (human leucocyte antigen; HLA) in HSCT for both malignant and non-malignant conditions. Because there is substantial variability in KIR gene content, allelic polymorphism, and cell-surface expression among people, careful selection of donors based on HLA and KIR is essential to optimize HSCT outcomes. Furthermore, NK cells may be used for adoptive immunotherapy after HSCT in place of conventional donor lymphocyte infusion, as part of pre-transplant cytoreductive therapy, or as an independent therapeutic agent in high-risk leukaemia in place of sibling donor HSCT.
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Molecular Assembly and Biosynthesis of Acetylcholinesterase in Brain and Muscle: the Roles of t-peptide, FHB Domain, and N-linked Glycosylation.
Front Mol Neurosci
PUBLISHED: 07-30-2011
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Acetylcholinesterase (AChE) is responsible for the hydrolysis of the neurotransmitter, acetylcholine, in the nervous system. The functional localization and oligomerization of AChE T variant are depending primarily on the association of their anchoring partners, either collagen tail (ColQ) or proline-rich membrane anchor (PRiMA). Complexes with ColQ represent the asymmetric forms (A(12)) in muscle, while complexes with PRiMA represent tetrameric globular forms (G(4)) mainly found in brain and muscle. Apart from these traditional molecular forms, a ColQ-linked asymmetric form and a PRiMA-linked globular form of hybrid cholinesterases (ChEs), having both AChE and BChE catalytic subunits, were revealed in chicken brain and muscle. The similarity of various molecular forms of AChE and BChE raises interesting question regarding to their possible relationship in enzyme assembly and localization. The focus of this review is to provide current findings about the biosynthesis of different forms of ChEs together with their anchoring proteins.
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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.