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Find video protocols related to scientific articles indexed in Pubmed.
Role of DNA sequence in chromatin remodeling and the formation of nucleosome-free regions.
Genes Dev.
PUBLISHED: 11-19-2014
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AT-rich DNA is concentrated in the nucleosome-free regions (NFRs) associated with transcription start sites of most genes. We tested the hypothesis that AT-rich DNA engenders NFR formation by virtue of its rigidity and consequent exclusion of nucleosomes. We found that the AT-rich sequences present in many NFRs have little effect on the stability of nucleosomes. Rather, these sequences facilitate the removal of nucleosomes by the RSC chromatin remodeling complex. RSC activity is stimulated by AT-rich sequences in nucleosomes and inhibited by competition with AT-rich DNA. RSC may remove NFR nucleosomes without effect on adjacent ORF nucleosomes. Our findings suggest that many NFRs are formed and maintained by an active mechanism involving the ATP-dependent removal of nucleosomes rather than a passive mechanism due to the intrinsic instability of nucleosomes on AT-rich DNA sequences.
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The Medical Education Pathway: Description and Early Outcomes of a Student-as-Teacher Program.
Acad Med
PUBLISHED: 10-30-2014
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Although senior medical students at the University of Rochester School of Medicine and Dentistry (URSMD) have a long history of teaching junior peers, no formal educational training existed for students until 2007. The Medical Education Pathway (MEP) at the URSMD is a longitudinal student-as-teacher program that addresses both the local precedent of medical student teaching and the ongoing need to prepare students for teaching in residency and beyond.
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Why or why not? A qualitative analysis of low-income parents' reasons for accepting or rejecting simulated research enrollment for their children.
Soc Work Public Health
PUBLISHED: 10-29-2014
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A simulation of enrollment in a high- or low-risk research study was conducted with low-income, mostly minority parents. Simulation participants were provided scenarios based on actual low-risk research involving premature babies or actual high-risk research involving devices designed as bridges to heart transplants when all other therapies had failed. Their understanding of the procedures, risks, and benefits was based only the information gained from consent materials for the high- or low-risk protocol. After reviewing the consent information, participants were asked to state their own decision as to whether to enroll their simulated child in the described study. The low-income sample of parents who participated in this simulation were overwhelmingly positive about enrolling a child in the two studies; 66% of those considering the high-risk study and 91% in the low-risk study indicated they would enroll a child. Parents in both conditions cited the value of learning ways to improve the health care of others as a primary reason for agreeing; they also valued knowledge for its own sake. Reasons for refusal varied according to the risk level. Many were unwilling to accept the risks involved in the high-risk study; parents considering the low-risk study of premature infants were concerned about possible discomforts for the infant. More of them also cited the length of the study and the need for repetitious follow-up visits. Information gained from the stated rationales gives insights into ways that researchers can enhance consent materials and the recruitment process.
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Nicotine Concentrations in Electronic Cigarette Refill and Do-It-Yourself Fluids.
Nicotine Tob. Res.
PUBLISHED: 05-28-2014
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We evaluate the accuracy of nicotine concentration labeling on electronic cigarette refill products.
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A retrospective study of end-stage renal disease in captive polar bears (Ursus maritimus).
J. Zoo Wildl. Med.
PUBLISHED: 04-10-2014
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This retrospective study summarizes 11 cases of end-stage renal disease (ESRD) in captive polar bears (Ursus maritimus) from eight zoologic institutions across the United States and Canada. Ten bears were female, one was male, and the mean age at the time of death was 24 yr old. The most common clinical signs were lethargy, inappetence, and polyuria-polydipsia. Biochemical findings included azotemia, anemia, hyperphosphatemia, and isosthenuria. Histologic examination commonly showed glomerulonephropathies and interstitial fibrosis. Based on submissions to a private diagnostic institution over a 16-yr period, ESRD was the most commonly diagnosed cause of death or euthanasia in captive polar bears in the United States, with an estimated prevalence of over 20%. Further research is needed to discern the etiology of this apparently common disease of captive polar bears.
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Development of EGFR-targeted nanoemulsion for imaging and novel platinum therapy of ovarian cancer.
Pharm. Res.
PUBLISHED: 02-24-2014
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Platinum-based chemotherapy is the treatment of choice for malignant epithelial ovarian cancers, but generalized toxicity and platinum resistance limits its use. Theranostic nanoemulsion with a novel platinum prodrug, myrisplatin, and the pro-apoptotic agent, C6-ceramide, were designed to overcome these limitations.
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Prospective molecular profiling of canine cancers provides a clinically relevant comparative model for evaluating personalized medicine (PMed) trials.
PLoS ONE
PUBLISHED: 01-01-2014
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Molecularly-guided trials (i.e. PMed) now seek to aid clinical decision-making by matching cancer targets with therapeutic options. Progress has been hampered by the lack of cancer models that account for individual-to-individual heterogeneity within and across cancer types. Naturally occurring cancers in pet animals are heterogeneous and thus provide an opportunity to answer questions about these PMed strategies and optimize translation to human patients. In order to realize this opportunity, it is now necessary to demonstrate the feasibility of conducting molecularly-guided analysis of tumors from dogs with naturally occurring cancer in a clinically relevant setting.
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Increasing nurse competence in peripheral intravenous therapy.
J Infus Nurs
PUBLISHED: 11-09-2013
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Infiltration and phlebitis are common complications associated with peripherally inserted vascular (PIV) therapy. This performance improvement plan included a pretest, a competency-based training module, and a posttest to determine whether nursing knowledge of infiltration and phlebitis improved. The postintervention data revealed a 50% reduction in infiltration and phlebitis. Annual education requirements combined with competency skills for assessing PIV catheter sites will provide nursing staff with the knowledge and tools to change current practice.
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Brominated flame retardants in breast milk and behavioural and cognitive development at 36 months.
Paediatr Perinat Epidemiol
PUBLISHED: 08-19-2013
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Polybrominated diphenyl ethers (PBDEs) are persistent flame retardants found in the environment, in household dust, and in humans. Breast feeding is a prominent route of exposure in infancy. PBDEs adversely affect neurodevelopment in animals. Here, we estimate associations between PBDEs in breast milk and behaviour and cognitive skills in children at 36 months of age.
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Sporadic naturally occurring melanoma in dogs as a preclinical model for human melanoma.
Pigment Cell Melanoma Res
PUBLISHED: 08-13-2013
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Melanoma represents a significant malignancy in humans and dogs. Different from genetically engineered models, sporadic canine melanocytic neoplasms share several characteristics with human disease that could make dogs a more relevant preclinical model. Canine melanomas rarely arise in sun-exposed sites. Most occur in the oral cavity, with a subset having intra-epithelial malignant melanocytes mimicking the in situ component of human mucosal melanoma. The spectrum of canine melanocytic neoplasia includes benign lesions with some analogy to nevi, as well as invasive primary melanoma, and widespread metastasis. Growing evidence of distinct subtypes in humans, differing in somatic and predisposing germ-line genetic alterations, cell of origin, epidemiology, relationship to ultraviolet radiation and progression from benign to malignant tumors, may also exist in dogs. Canine and human mucosal melanomas appear to harbor BRAF, NRAS, and c-kit mutations uncommonly, compared with human cutaneous melanomas, although both species share AKT and MAPK signaling activation. We conclude that there is significant overlap in the clinical and histopathological features of canine and human mucosal melanomas. This represents opportunity to explore canine oral cavity melanoma as a preclinical model.
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A transient increase in lipid peroxidation primes preadipocytes for delayed mitochondrial inner membrane permeabilization and ATP depletion during prolonged exposure to fatty acids.
Free Radic. Biol. Med.
PUBLISHED: 08-08-2013
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Preadipocytes are periodically subjected to fatty acid (FA) concentrations that are potentially cytotoxic. We tested the hypothesis that prolonged exposure of preadipocytes of human origin to a physiologically relevant mix of FAs leads to mitochondrial inner membrane (MIM) permeabilization and ultimately to mitochondrial crisis. We found that exposure of preadipocytes to FAs led to progressive cyclosporin A-sensitive MIM permeabilization, which in turn caused a reduction in MIM potential, oxygen consumption, and ATP synthetic capacity and, ultimately, death. Additionally, we showed that FAs induce a transient increase in intramitochondrial reactive oxygen species (ROS) and lipid peroxide production, lasting roughly 30 and 120min for the ROS and lipid peroxides, respectively. MIM permeabilization and its deleterious consequences including mitochondrial crisis and cell death were prevented by treating the cells with the mitochondrial FA uptake inhibitor etomoxir, the mitochondrion-selective superoxide and lipid peroxide antioxidants MitoTempo and MitoQ, or the lipid peroxide and reactive carbonyl scavenger l-carnosine. FAs also promoted a delayed oxidative stress phase. However, the beneficial effects of etomoxir, MitoTempo, and l-carnosine were lost by delaying the treatment by 2h, suggesting that the initial phase was sufficient to prime the cells for the delayed MIM permeabilization and mitochondrial crisis. It also suggested that the second ROS production phase is a consequence of this loss in mitochondrial health. Altogether, our data suggest that approaches designed to diminish intramitochondrial ROS or lipid peroxide accumulation, as well as MIM permeabilization, are valid mechanism-based therapeutic avenues to prevent the loss in preadipocyte metabolic fitness associated with prolonged exposure to elevated FA levels.
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Evaluation of Rhodiola rosea supplementation on skeletal muscle damage and inflammation in runners following a competitive marathon.
Brain Behav. Immun.
PUBLISHED: 07-05-2013
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Adaptogens modulate intracellular signaling and increase expression of heat shock protein 72 (HSP72). Rhodiola rosea (RR) is a medicinal plant with demonstrated adaptogenic properties. The purpose of this study was to measure the influence of RR supplementation on exercise-induced muscle damage, delayed onset of muscle soreness (DOMS), plasma cytokines, and extracellular HSP72 (eHSP72) in experienced runners completing a marathon. Experienced marathon runners were randomized to RR (n=24, 6 female, 18 male) or placebo (n=24, 7 female, 17 male) groups and under double-blinded conditions ingested 600mg/day RR extract or placebo for 30days prior to, the day of, and seven days post-marathon. Blood samples were collected, and vertical jump and DOMS assessed the day before, 15min post- and 1.5h post-marathon. DOMS was also assessed for seven days post-marathon. Marathon race performance did not differ between RR and placebo groups (3.87±0.12h and 3.93±0.12h, respectively, p=0.722). Vertical jump decreased post-marathon (time effect, p<0.001) with no difference between groups (interaction effect, p=0.673). Post-marathon DOMS increased significantly (p<0.001) but the pattern of change did not differ between groups (p=0.700). Myoglobin (Mb), creatine phosphokinase (CPK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), interleukin (IL)-6, IL-8, IL-10, monocyte chemotactic protein-1 (MCP-1), granulocyte-colony-stimulating factor (G-CSF), C-reactive protein (CRP), and eHSP72 all increased post-marathon (all p<0.001), with no group differences over time (all p>0.300). In conclusion, RR supplementation (600mg/day) for 30days before running a marathon did not attenuate the post-marathon decrease in muscle function, or increases in muscle damage, DOMS, eHSP72, or plasma cytokines in experienced runners.
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Increasing social interaction using prelinguistic milieu teaching with nonverbal school-age children with autism.
Am J Speech Lang Pathol
PUBLISHED: 06-28-2013
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Children with autism display marked deficits in initiating and maintaining social interaction. Intervention using play routines can create a framework for developing and maintaining social interaction between these children and their communication partners.
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Studies in experimental autoimmune encephalomyelitis do not support developmental bisphenol a exposure as an environmental factor in increasing multiple sclerosis risk.
Toxicol. Sci.
PUBLISHED: 06-23-2013
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Multiple sclerosis (MS), a demyelinating immune-mediated central nervous system disease characterized by increasing female penetrance, is the leading cause of disability in young adults in the developed world. Epidemiological data strongly implicate an environmental factor, acting at the population level during gestation, in the increasing incidence of female MS observed over the last 50 years, yet the identity of this factor remains unknown. Gestational exposure to bisphenol A (BPA), an endocrine disruptor used in the manufacture of polycarbonate plastics since the 1950s, has been reported to alter a variety of physiological processes in adulthood. BPA has estrogenic activity, and we hypothesized that increased gestational exposure to environmental BPA may therefore contribute to the increasing female MS risk. To test this hypothesis, we utilized two different mouse models of MS, experimental autoimmune encephalomyelitis (EAE) in C57BL/6J mice (chronic progressive) and in SJL/J mice (relapsing-remitting). Dams were exposed to physiologically relevant levels of BPA in drinking water starting 2 weeks prior to mating and continuing until weaning of offspring. EAE was induced in adult offspring. No significant changes in EAE incidence, progression, or severity were observed with BPA exposure, despite changes in cytokine production by autoreactive T cells. However, endocrine disruption was evidenced by changes in testes development, and transcriptomic profiling revealed that BPA exposure altered the expression of several genes important for testes development, including Pdgfa, which was downregulated. Overall, our results do not support gestational BPA exposure as a significant contributor to the increasing female MS risk.
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Perinatally administered bisphenol a as a potential mammary gland carcinogen in rats.
Environ. Health Perspect.
PUBLISHED: 03-01-2013
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Environmental exposure to bisphenol A (BPA) affects mammary gland development in rodents and primates. Prenatal exposure to environmentally relevant doses of BPA increased the number of intraductal hyperplasias and ductal carcinomas in situ by 50 days of age in Wistar-Furth rats.
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Gene expression in uterine leiomyoma from tumors likely to be growing (from black women over 35) and tumors likely to be non-growing (from white women over 35).
PLoS ONE
PUBLISHED: 01-01-2013
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The study of uterine leiomyomata (fibroids) provides a unique opportunity to investigate the physiological and molecular determinants of hormone dependent tumor growth and spontaneous tumor regression. We conducted a longitudinal clinical study of premenopausal women with leiomyoma that showed significantly different growth rates between white and black women depending on their age. Growth rates for leiomyoma were on average much higher from older black women than for older white women, and we now report gene expression pattern differences in tumors from these two groups of study participants. Total RNA from 52 leiomyoma and 8 myometrial samples were analyzed using Affymetrix Gene Chip expression arrays. Gene expression data was first compared between all leiomyoma and normal myometrium and then between leiomyoma from older black women (age 35 or older) and from older white women. Genes that were found significant in pairwise comparisons were further analyzed for canonical pathways, networks and biological functions using the Ingenuity Pathway Analysis (IPA) software. Whereas our comparison of leiomyoma to myometrium produced a very large list of genes highly similar to numerous previous studies, distinct sets of genes and signaling pathways were identified in comparisons of older black and white women whose tumors were likely to be growing and non-growing, respectively. Key among these were genes associated with regulation of apoptosis. To our knowledge, this is the first study to compare two groups of tumors that are likely to have different growth rates in order to reveal molecular signals likely to be influential in tumor growth.
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Mouse relapse model of Clostridium difficile infection.
Infect. Immun.
PUBLISHED: 05-16-2011
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Clostridium difficile is the causative agent of primary and recurrent antibiotic-associated diarrhea and colitis in hospitalized patients. The disease is caused mainly by two exotoxins, TcdA and TcdB, produced by the bacteria. Recurrent C. difficile infection (CDI) constitutes one of the most significant clinical issues of this disease, occurs in more than 20% of patients after the first episode, and may be increasing in frequency. However, there is no well-established animal model of CDI relapse currently available for studying disease pathogenesis, prevention, and therapy. Here we report the establishment of a conventional mouse model of recurrence/relapse CDI. We found that the primary episode of CDI induced little or no protective antibody response against C. difficile toxins and mice continued shedding C. difficile spores. Antibiotic treatment of surviving mice induced a second episode of diarrhea, while a simultaneous reexposure of animals to C. difficile bacteria or spores elicited a full spectrum of CDI similar to that of the primary infection. Moreover, mice treated with immunosuppressive agents were prone to more severe and fulminant recurrent disease. Finally, utilizing this model, we demonstrated that vancomycin only delayed disease recurrence, whereas neutralizing polysera against both TcdA and TcdB completely protected mice against CDI relapse. In conclusion, we have established a mouse relapse CDI model that allows for future investigations of the role of the host immune response in the diseases pathogenesis and permits critical testing of new therapeutics targeting recurrent disease.
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Selective removal of promoter nucleosomes by the RSC chromatin-remodeling complex.
Nat. Struct. Mol. Biol.
PUBLISHED: 04-22-2011
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Purified chromatin rings, excised from the PHO5 locus of Saccharomyces cerevisiae in transcriptionally repressed and activated states, were remodeled with RSC and ATP. Nucleosomes were translocated, and those originating on the promoter of repressed rings were removed, whereas those originating on the open reading frame (ORF) were retained. Treatment of the repressed rings with histone deacetylase diminished the removal of promoter nucleosomes. These findings point to a principle of promoter chromatin remodeling for transcription, namely that promoter specificity resides primarily in the nucleosomes rather than in the remodeling complex that acts upon them.
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Infants perceived as "fussy" are more likely to receive complementary foods before 4 months.
Pediatrics
PUBLISHED: 01-10-2011
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Our purpose was to assess early infant-feeding patterns in a cohort of low-income black mothers and to examine associations between maternal perception of infant temperament and complementary feeding (CF) before 4 months.
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Maternal role attainment with medically fragile infants: Part 2. relationship to the quality of parenting.
Res Nurs Health
PUBLISHED: 11-17-2010
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We examined which components of maternal role attainment (identity, presence, competence) influenced quality of parenting for 72 medically fragile infants, controlling for maternal education and infant illness severity. Maternal competence was related to responsiveness. Maternal presence and technology dependence were inversely related to participation. Greater competence and maternal education were associated with better normal caregiving. Presence was negatively related although competence was positively related to illness-related caregiving. Mothers with lower competence and more technology dependent children perceived their children as more vulnerable and child cues as more difficult to read. Maternal role attainment influenced parenting quality for these infants more than did child illness severity; thus interventions are needed to help mothers develop their maternal role during hospitalization and after discharge. © 2010 Wiley Periodicals, Inc. Res Nurs Health 34:35-48, 2011.
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Analytical performance evaluation of ADVIA Chemistry Carbamazepine_2 assay: minimal cross-reactivity with carbamazepine 10, 11-epoxide and none with hydroxyzine or cetirizine.
J. Clin. Lab. Anal.
PUBLISHED: 07-14-2010
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Carbamazepine is an anticonvulsant requiring routine therapeutic drug monitoring. Recently, Siemens Healthcare Diagnostic Division released a new carbamazepine assay: ADVIA Chemistry Carbamazepine_2 (Carbamazepine_2) for application on ADVIA analyzers. We evaluated the analytical performance of this assay as well as its potential cross-reactivities with carbamazepine 10, 11-epoxide, hydroxyzine, and cetirizine. The within-run and between-run precisions of the Carbamzepine-2 assay were <6% and limit of detection was 0.5 microg/ml using ADVIA 1800 analyzer. The assay was linear up to a carbamazepine concentration of 20.0 microg/ml. The new method compared well with a widely used carbamazepine EMIT 2000 assay on the Hitachi 917 analyzer. Using 75 patients specimens (where carbamazepine concentrations varied from 0.5 to 21.7 microg/ml) and carbamazepine EMIT 2000 as the reference method (x-axis), we observed the following regression equation: y=1.04 x+0.32 (r=0.99). The new carbazepine_2 method was not affected by a hemoglobin concentration of 1,000 mg/dl, conjugated or unconjugated bilirubin concentration of 60 mg/dl, and triglyceride concentration of 1,000 mg/dl. In addition, this assay showed no cross-reactivity with hydroxyzine or cetirizine and demonstrated minimal cross-reactivity with carbamazepine 10, 11-epoxide. We conclude that the ADVIA Chemistry carbamazepine_2 assay has adequate precision and accuracy for routine therapeutic drug monitoring of carbamazepine in clinical laboratories.
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Testing a Swedish version of the Consumer Emergency Care Satisfaction Scale in an emergency department and 2 observation wards.
J Nurs Care Qual
PUBLISHED: 06-03-2010
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The aim was to investigate the construct validity and internal consistency of the Swedish version of the Consumer Emergency Care Satisfaction Scale. The sample comprised 157 persons from an emergency department and an observation ward. The results showed satisfactory reliability, and an explorative factor analysis revealed 3 factors: Caring, Teaching, and Clinical Competence. The Swedish version of the scale seems reliable and may be a useful tool for measuring satisfaction in different acute care settings.
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Short-term change in growth of uterine leiomyoma: tumor growth spurts.
Fertil. Steril.
PUBLISHED: 03-22-2010
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To describe the short-term changes in growth of uterine leiomyomas (fibroids).
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Infant overweight is associated with delayed motor development.
J. Pediatr.
PUBLISHED: 03-15-2010
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To examine how infant overweight and high subcutaneous fat relate to infant motor development.
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Accuracy of consonant-vowel syllables in young cochlear implant recipients and hearing children in the single-word period.
J. Speech Lang. Hear. Res.
PUBLISHED: 02-13-2010
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Attaining speech accuracy requires that children perceive and attach meanings to vocal output on the basis of production system capacities. Because auditory perception underlies speech accuracy, profiles for children with hearing loss (HL) differ from those of children with normal hearing (NH).
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Mechanism of chromatin remodeling.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-08-2010
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Results from biochemical and structural studies of the RSC chromatin-remodeling complex prompt a proposal for the remodeling mechanism: RSC binding to the nucleosome releases the DNA from the histone surface and initiates DNA translocation (through one or a small number of DNA base pairs); ATP binding completes translocation, and ATP hydrolysis resets the system. Binding energy thus plays a central role in the remodeling process. RSC may disrupt histone-DNA contacts by affecting histone octamer conformation and through extensive interaction with the DNA. Bulging of the DNA from the octamer surface is possible, and twisting is unavoidable, but neither is the basis of remodeling.
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Transcriptional biomarkers of steroidogenesis and trophoblast differentiation in the placenta in relation to prenatal phthalate exposure.
Environ. Health Perspect.
PUBLISHED: 02-04-2010
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Phthalates can alter steroidogenesis and peroxisome proliferator-activated receptor gamma (PPARgamma)mediated transcription in rodent tissues. The placenta offers a rich source of biomarkers to study these relationships in humans.
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Correlation of the time course of development and decay of tolerance to morphine with alterations in sodium pump protein isoform abundance.
Biochem. Pharmacol.
PUBLISHED: 09-01-2009
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Since the heterologous tolerance that develops after chronic morphine administration has been proposed to be an adaptive process, it follows that the time course of the change in the cellular components should coincide with the time course of the altered responsiveness. This study correlated the time course over which heterologous tolerance develops with changes in the abundance of selected proteins in the guinea-pig longitudinal muscle/myenteric plexus (LM/MP) preparation. Tissues were obtained at various times following a single surgical implantation procedure and heterologous tolerance confirmed by a significant reduction in the sensitivity of the LM/MP to inhibition of neurogenic twitches by morphine, DAMGO, and 2-CADO. Tolerance developed with a delayed onset (significant 2-5-fold reduction in sensitivity by day 4 after pellet implantation) that reached a maximum by 7 days (4-8-fold reduction in responsiveness) that was maintained through 14 days with normal sensitivity spontaneously returning by 21 days post-implantation. Dot blot analysis was used to examine the abundance of the alpha(1) and alpha(3) subunit isoforms of the Na(+)/K(+) ATPase and beta-actin over the same time course. The results showed significant decreases in abundance of the alpha(3) subunit at 4, 7, and 10 days following pellet implantation but no change in beta-actin or the alpha(1) subunit at any time period. These data support the idea that heterologous tolerance following chronic morphine exposure results from a cellular adaptive change that may involve a change in the abundance of the alpha(3) subunit isoform of the Na(+)/K(+) ATPase.
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Producing American English vowels during vocal tract growth: a perceptual categorization study of synthesized vowels.
J. Speech Lang. Hear. Res.
PUBLISHED: 08-20-2009
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To consider interactions of vocal tract change with growth and perceived output patterns across development, the influence of nonuniform vocal tract growth on the ability to reach acoustic-perceptual targets for English vowels was studied.
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Infant temperament contributes to early infant growth: A prospective cohort of African American infants.
Int J Behav Nutr Phys Act
PUBLISHED: 08-05-2009
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Prospective studies linking infant temperament, or behavioral style, to infant body composition are lacking. In this longitudinal study (3 to 18 months), we seek to examine the associations between two dimensions of infant temperament (distress to limitations and activity level) and two anthropometric indicators (weight-for-length z-scores (WLZ) and skin fold (SF) measures) in a population at high risk of overweight.
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Segmental distribution patterns of English infant- and adult-directed speech.
J Child Lang
PUBLISHED: 07-02-2009
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This study compared segmental distribution patterns for consonants and vowels in English infant-directed speech (IDS) and adult-directed speech (ADS). A previous study of Korean indicated that segmental patterns of IDS differed from ADS patterns (Lee, Davis & MacNeilage, 2008). The aim of the current study was to determine whether such differences in Korean are universal or language-specific. Results indicate that consonant distribution patterns of English IDS were significantly different from English ADS. Speakers who used IDS produced fewer fricatives, affricates, nasals and liquids, but more stops and glides, than speakers who used ADS. In terms of vowels, IDS speakers produced more high-back vowels /u / and /open oI/ diphthongs than ADS speakers. These results indicate both general trends and language-specific segmental distribution patterns in IDS. When compared to previous findings on ADS and IDS in Korean, these results for English give support to a more general assertion that segmental distribution patterns in IDS seem to be mediated by linguistic and cultural factors across languages.
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Universal production patterns and ambient language influences in babbling: a cross-linguistic study of Korean- and English-learning infants.
J Child Lang
PUBLISHED: 07-02-2009
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The phonetic characteristics of canonical babbling produced by Korean- and English-learning infants were compared with consonant and vowel frequencies observed in infant-directed speech produced by Korean- and English-speaking mothers. For infant output, babbling samples from six Korean-learning infants were compared with an existing English babbling database (Davis & MacNeilage, 1995). For ambient language comparisons, consonants and vowels in ten Korean and ten English infant-directed speech (IDS) samples were analyzed. The two infant groups demonstrated similar consonant patterns, but showed different vowel patterns from one another. For both languages, infant vowel patterns were related to those of ambient language IDS. Ambient language patterns were manifested in infant vowel output, perhaps because vowels are more perceptually and motorically available in the input and output capacities of babbling infants.
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Alterations to functional analysis methodology to clarify the functions of low rate, high intensity problem behavior.
Behav Anal Pract
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Current research provides few suggestions for modifications to functional analysis procedures to accommodate low rate, high intensity problem behavior. This study examined the results of the extended duration functional analysis procedures of Kahng, Abt, and Schonbachler (2001) with six children admitted to an inpatient hospital for the treatment of severe problem behavior. Results of initial functional analyses (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) were inconclusive for all children because of low levels of responding. The altered functional analyses, which changed multiple variables including the duration of the functional analysis (i.e., 6 or 7 hrs), yielded clear behavioral functions for all six participants. These results add additional support for the utility of an altered analysis of low rate, high intensity problem behavior when standard functional analyses do not yield differentiated results.
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Phosphatidylcholine supplementation in pregnant women consuming moderate-choline diets does not enhance infant cognitive function: a randomized, double-blind, placebo-controlled trial.
Am. J. Clin. Nutr.
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Choline is essential for fetal brain development, and it is not known whether a typical American diet contains enough choline to ensure optimal brain development.
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Associations between white matter microstructure and infants working memory.
Neuroimage
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Working memory emerges in infancy and plays a privileged role in subsequent adaptive cognitive development. The neural networks important for the development of working memory during infancy remain unknown. We used diffusion tensor imaging (DTI) and deterministic fiber tracking to characterize the microstructure of white matter fiber bundles hypothesized to support working memory in 12-month-old infants (n=73). Here we show robust associations between infants visuospatial working memory performance and microstructural characteristics of widespread white matter. Significant associations were found for white matter tracts that connect brain regions known to support working memory in older children and adults (genu, anterior and superior thalamic radiations, anterior cingulum, arcuate fasciculus, and the temporal-parietal segment). Better working memory scores were associated with higher FA and lower RD values in these selected white matter tracts. These tract-specific brain-behavior relationships accounted for a significant amount of individual variation above and beyond infants gestational age and developmental level, as measured with the Mullen Scales of Early Learning. Working memory was not associated with global measures of brain volume, as expected, and few associations were found between working memory and control white matter tracts. To our knowledge, this study is among the first demonstrations of brain-behavior associations in infants using quantitative tractography. The ability to characterize subtle individual differences in infant brain development associated with complex cognitive functions holds promise for improving our understanding of normative development, biomarkers of risk, experience-dependent learning and neuro-cognitive periods of developmental plasticity.
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Comparison of electronic cigarette refill fluid cytotoxicity using embryonic and adult models.
Reprod. Toxicol.
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Electronic cigarettes (EC) and refill fluids are distributed with little information on their pre- and postnatal health effects. This study compares the cytotoxicity of EC refill fluids using embryonic and adult cells and examines the chemical characteristics of refill fluids using HPLC. Refill solutions were tested on human embryonic stem cells (hESC), mouse neural stem cells (mNSC), and human pulmonary fibroblasts (hPF) using the MTT assay, and NOAELs and IC(50)s were determined from dose-response curves. Spectral analysis was performed when products of the same flavor had different MTT outcomes. hESC and mNSC were generally more sensitive to refill solutions than hPF. All products from one company were cytotoxic to hESC and mNSC, but non-cytotoxic to hPF. Cytotoxicity was not due to nicotine, but was correlated with the number and concentration of chemicals used to flavor fluids. Additional studies are needed to fully assess the prenatal effect of refill fluids.
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Lactational exposure to polybrominated diphenyl ethers and its relation to social and emotional development among toddlers.
Environ. Health Perspect.
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Polybrominated diphenyl ethers (PBDEs) have been widely used as flame retardants and are ubiquitous environmental contaminants. PBDEs have been linked to adverse neurodevelopment in animals and humans.
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Manipulating motivating operations to facilitate the emergence of mands for a child with autism.
Anal Verbal Behav
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Research on the functional independence of verbal operants (Skinner, 1957) has demonstrated inconsistent findings. One explanation may be that these studies have not manipulated the motivating operation (MO) to facilitate the emergence of mands (Hall & Sundberg, 1987; Lamarre & Holland, 1985). In the current study, 1 participant, diagnosed with autism, was taught to tact high-preference and low-preference leisure items, and emergence of mands was tested under varying MO conditions. Results showed the emergence of mands following periods of arranged deprivation, and greater maintenance for a highly preferred relative to a less preferred stimulus. However, mands only emerged when presession tact trials were conducted. These results suggest that in a state of deprivation, transfer of stimulus control from discriminative to motivational conditions may occur without direct training.
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The influence of phonetic complexity on stuttered speech.
Clin Linguist Phon
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The primary purpose of this study was to re-examine the influence of phonetic complexity on stuttering in young children through the use of the Word Complexity Measure (WCM). Parent-child conversations were transcribed for 14 children who stutter (mean age = 3 years, 7 months; SD = 11.20 months). Lexical and linguistic factors were accounted for during the analysis. Results indicate that phonetic complexity, as measured by WCM, did not exhibit a significant influence on the likelihood of stuttering. Findings support previous data that suggest stuttering in preschool-age children does not appear significantly related to phonetic complexity of the production.
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Prenatal isolated mild ventriculomegaly is associated with persistent ventricle enlargement at ages 1 and 2.
Early Hum. Dev.
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Enlargement of the lateral ventricles is thought to originate from abnormal prenatal brain development and is associated with neurodevelopmental disorders. Fetal isolated mild ventriculomegaly (MVM) is associated with the enlargement of lateral ventricle volumes in the neonatal period and developmental delays in early childhood. However, little is known about postnatal brain development in these children.
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EGF receptor (ERBB1) abundance in adipose tissue is reduced in insulin-resistant and type 2 diabetic women.
J. Clin. Endocrinol. Metab.
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Indications of adipose tissue dysfunction correlate with systemic insulin resistance and type 2 diabetes. It has been suggested that a defect in adipose tissue turnover may be involved in the development of these disorders. Whether this dysfunction causes or exacerbates systemic insulin resistance is not fully understood. OBJECTIVES, PARTICIPANTS, AND MEASURES: We tested whether the expression of members of the mitogenic ErbB family was reduced in adipose tissue of insulin-resistant individuals and whether ErbB1 and ErbB2 were involved in adipogenesis. Thirty-two women covering a wide range of body mass index values and insulin sensitivity participated in the cross-sectional portion of this study. We also studied preadipocytes isolated from 12 insulin-sensitive individuals to evaluate the impact of ErbB1 or ErbB2 inhibition on adipogenesis in vitro. For this purpose, we measured phospho-ErbB1 and phospho-ErbB2 levels using ELISA and the expression of peroxisome proliferator-activated receptor ? (PPAR?) and PPAR?-regulated genes by real-time PCR.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.