ABSTRACT
To determine the error rate of transcription in human cells, we analyzed the transcriptome of H1 human embryonic stem cells with a circle-sequencing approach that allows for high-fidelity sequencing of the transcriptome. These experiments identified approximately 100,000 errors distributed over every major RNA species in human cells. Our results indicate that different RNA species display different error rates, suggesting that human cells prioritize the fidelity of some RNAs over others. Cross-referencing the errors that we detected with various genetic and epigenetic features of the human genome revealed that the in vivo error rate in human cells changes along the length of a transcript and is further modified by genetic context, repetitive elements, epigenetic markers, and the speed of transcription. Our experiments further suggest that BRCA1, a DNA repair protein implicated in breast cancer, has a previously unknown role in the suppression of transcription errors. Finally, we analyzed the distribution of transcription errors in multiple tissues of a new mouse model and found that they occur preferentially in neurons, compared to other cell types. These observations lend additional weight to the idea that transcription errors play a key role in the progression of various neurological disorders, including Alzheimer's disease.
Subject(s)
RNA , Transcription, Genetic , Animals , Mice , Humans , RNA/genetics , Transcriptome , Proteins/genetics , Repetitive Sequences, Nucleic AcidABSTRACT
Zinc oxide is an environmentally friendly and readily synthesized semiconductor with many industrial applications. ZnO powders were prepared by alkali precipitation using different [Zn(acetate)2(amine)x] compounds to alter the particle size and aspect ratio. Slow precipitations from 95 °C solutions produced micron-scale particles with morphologies of hexagonal plates, rods, and needles, depending on the precursor used. Powders prepared at 65 °C with rapid precipitation yielded particles with minimal morphology differences, but particle size was dependent on the precursor used. The smallest particles were produced using precursors that yielded crystals with low aspect ratios during high-temperature synthesis. Particles produced during rapid synthesis had sizes ranging from 21-45 nm. The materials were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, BET, and diffuse reflectance. The materials prepared using precursors with less-volatile amines were found to retain more organic material than ZnO produced using precursors with more volatile amines. The amount of organic material associated with the nanoparticles influenced the photocatalytic activity of the ZnO, with powders containing less organic material producing faster rate constants for the decolorizing of malachite green solutions under ultraviolet illumination, independent of particle size. [Zn(acetate)2(hydrazine)2] produced ZnO with the fastest rate constant and was recycled five times for dye degradation studies that revealed minimal to no reduction in catalytic efficiency.
ABSTRACT
Veratrum californicum is a rich source of steroidal alkaloids, many of which have proven to be antagonists of the Hedgehog (Hh) signaling pathway that becomes aberrant in over twenty types of cancer. These alkaloids first became known in the 1950's due to their teratogenic properties, which resulted in newborn and fetal lambs developing cyclopia as a result of pregnant ewes consuming Veratrum californicum. It was discovered that the alkaloids in V. californicum were concentrated in the root and rhizome of the plant with much lower amounts of the most active alkaloid, cyclopamine, present in the aerial plant, especially in the late growth season. Inspired by the limitations in analytical instrumentation and methods available to researchers at the time of the original investigation, we have used state-of-the-art instrumentation and modern analytical methods to quantitate four steroidal alkaloids based on study parameters including plant part, harvest location, and growth stage. The results of the current inquiry detail differences in alkaloid composition based on the study parameters, provide a detailed assessment for alkaloids that have been characterized previously (cyclopamine, veratramine, muldamine and isorubijervine), and identify at least six alkaloids that have not been previously characterized. This study provides insight into optimal harvest time, plant growth stage, harvest location, and plant part required to isolate, yet to be characterized, alkaloids of interest for exploration as Hh pathway antagonists with desirable medicinal properties.
Subject(s)
Alkaloids/chemistry , Steroids/chemistry , Veratrum/chemistry , Alkaloids/isolation & purification , Hedgehog Proteins/antagonists & inhibitors , Idaho , Molecular Structure , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Plant Components, Aerial/chemistry , Rhizome/chemistry , Seasons , Steroids/isolation & purification , Veratrum AlkaloidsABSTRACT
STUDY DESIGN: Mapping review. INTRODUCTION: Although published literature and evidence to support medical practice is becoming more abundant, it is not known how well available evidence supports the full spectrum of hand therapy practice. PURPOSE OF THE STUDY: The aim of this mapping review was to identify strengths and/or gaps in the available literature as compared with the hand therapy scope of practice to guide future research. METHODS: A systematic search and screening was conducted to identify evidence published from 2006 to 2015. Descriptive data from 191 studies were extracted, and the diagnoses, interventions, and outcomes used in the literature were compared with the hand therapy scope of practice. RESULTS: Osteoarthritis, tendon surgeries, and carpal tunnel syndrome were most frequently studied. Exercise, education, and orthotic interventions were most common, each used in more than 100 studies; only 12 studies used activity-based interventions. Primary outcome measures included range of motion, pain/symptoms, strength, and functional status. DISCUSSION: Abundant high-quality research exists for a portion of the hand therapy scope of practice; however, there is a paucity of evidence for numerous diagnoses and interventions. CONCLUSIONS: More evidence is needed for complex diagnoses and activity-based interventions as well as behavioral and quality-of-care outcomes. LEVEL OF EVIDENCE: Not applicable.
Subject(s)
Musculoskeletal Diseases/therapy , Occupational Therapy , Physical Therapy Modalities , Equipment Design , Humans , Orthotic Devices , Patient Education as Topic , Patient Reported Outcome Measures , Scope of PracticeABSTRACT
Multiple pathogenic factors have been suggested to play a role in the development of Alzheimer's disease (AD). The multifactorial nature of AD also suggests the potential use of compounds with polypharmacology as effective disease-modifying agents. Recently, we have developed a bivalent strategy to include cell membrane anchorage into the molecular design. Our results demonstrated that the bivalent compounds exhibited multifunctional properties and potent neuroprotection in a cellular AD model. Herein, we report the mechanistic exploration of one of the representative bivalent compounds, 17MN, in MC65 cells. Our results established that MC65 cells die through a necroptotic mechanism upon the removal of tetracycline (TC). Furthermore, we have shown that mitochondrial membrane potential and cytosolic Ca2+ levels are increased upon removal of TC. Our bivalent compound 17MN can reverse such changes and protect MC65 cells from TC removal induced cytotoxicity. The results also suggest that 17MN may function between the Aß species and RIPK1 in producing its neuroprotection. Colocalization studies employing a fluorescent analog of 17MN and confocal microscopy demonstrated the interactions of 17MN with both mitochondria and endoplasmic reticulum, thus suggesting that 17MN exerts its neuroprotection via a multiple-site mechanism in MC65 cells. Collectively, these results strongly support our original design rationale of bivalent compounds and encourage further optimization of this bivalent strategy to develop more potent analogs as novel disease-modifying agents for AD.
Subject(s)
Alzheimer Disease/drug therapy , Cholesterol/analogs & derivatives , Curcumin/analogs & derivatives , Neuroprotective Agents/pharmacology , Alzheimer Disease/pathology , Alzheimer Disease/physiopathology , Amyloid beta-Peptides/metabolism , Animals , Apoptosis/drug effects , Apoptosis/physiology , Brain/drug effects , Brain/pathology , Brain/physiopathology , Calcium/metabolism , Caspase 3/metabolism , Cell Line, Tumor , Cholesterol/chemistry , Cholesterol/pharmacology , Curcumin/chemistry , Curcumin/pharmacology , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/pathology , Endoplasmic Reticulum/physiology , Humans , Male , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/physiology , Mice, Inbred C57BL , Molecular Structure , Neuroprotective Agents/chemistry , Peptide Fragments/metabolism , Receptor-Interacting Protein Serine-Threonine Kinases/metabolismABSTRACT
PURPOSE: To determine if primary open-angle glaucoma (POAG) patients can be differentiated from controls based on metabolic characteristics. METHODS: We used ultra-high resolution mass spectrometry with C18 liquid chromatography for metabolomic analysis on frozen plasma samples from 72 POAG patients and 72 controls. Metabolome-wide Spearman correlation was performed to select differentially expressed metabolites (DEM) correlated with POAG. We corrected P values for multiple testing using Benjamini and Hochberg false discovery rate (FDR). Hierarchical cluster analysis (HCA) was used to depict the relationship between participants and DEM. Differentially expressed metabolites were matched to the METLIN metabolomics database; both DEM and metabolites significantly correlating with DEM were analyzed using MetaboAnalyst to identify metabolic pathways altered in POAG. RESULTS: Of the 2440 m/z (mass/charge) features recovered after filtering, 41 differed between POAG cases and controls at FDR = 0.05. Hierarchical cluster analysis revealed these DEM to associate into eight clusters; three of these clusters contained the majority of the DEM and included palmitoylcarnitine, hydroxyergocalciferol, and high-resolution METLIN matches to sphingolipids, other vitamin D-related metabolites, and terpenes. MetaboAnalyst also indicated likely alteration in steroid biosynthesis pathways. CONCLUSIONS: Global ultrahigh resolution metabolomics emphasized the importance of altered lipid metabolism in POAG. The results suggest specific metabolic processes, such as those involving palmitoylcarnitine, sphingolipids, vitamin D-related compounds, and steroid precursors, may contribute to POAG status and merit more detailed study with targeted methods.
Subject(s)
Eye Proteins/metabolism , Glaucoma, Open-Angle/metabolism , Metabolome/physiology , Metabolomics/methods , Aged , Female , Humans , Male , Mass Spectrometry , Middle AgedABSTRACT
PURPOSE: To determine if specific mitochondrial haplogroups associate with nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR). METHODS: Deidentified medical records for Caucasian patients with diabetic retinopathy (DR; 153 NPDR and 138 PDR) were obtained from BioVU, Vanderbilt University's electronic, deidentified DNA databank. An independent cohort of Caucasian patients with DR (44 NPDR and 57 PDR) from the Vanderbilt Eye Institute (VEI) was used for validation. We tested for an association between mitochondrial haplogroups and PDR among patients with DR. RESULTS: In the BioVU cohort, PDR frequency among Caucasian DR patients differed significantly by mitochondrial haplogroup (P = 0.027). Replication in the VEI cohort confirmed this association (P = 0.0064). In the combined cohort, patients from the common haplogroup H were more likely to have PDR (odds ratio [OR] = 2.0 [95% confidence interval (CI) = 1.3-3.0], P = 0.0012), while patients from haplogroup Uk were less likely to have PDR (OR = 0.5 [95% CI = 0.3-0.8], P = 0.0049). In logistic regression analyses, the addition of diabetes duration, hemoglobin A1c (HgbA1c) levels, and hypertension had no effect on the associations of haplogroups H and Uk with PDR. CONCLUSIONS: In this study, DR patients from mitochondrial haplogroup H were more likely to have PDR, while DR patients from haplogroup Uk were less likely to have PDR. The association was independent of the major clinical variables affecting PDR. The mitochondrial haplogroups were as strong a risk factor for PDR as were elevated HgbA1c levels.
Subject(s)
Diabetic Retinopathy/genetics , Haplotypes , Mitochondria/genetics , Adult , Aged , Case-Control Studies , Cohort Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 2/complications , Diabetic Retinopathy/blood , Female , Genotype , Glycated Hemoglobin/analysis , Humans , Male , Middle Aged , Odds RatioABSTRACT
OBJECTIVE: The present preliminary trials tested whether undergraduate peer leaders can effectively deliver a dissonance-based eating disorder prevention program, which could facilitate broad dissemination of this efficacious intervention. METHOD: In Study 1, female undergraduates (N=171) were randomized to peer-led groups, clinician-led groups, or an educational brochure control condition. In Study 2, which improved a design limitation of Study 1 by using completely parallel outcome measures across conditions, female undergraduates (N=148) were randomized to either immediate peer-led groups or a waitlist control condition. RESULTS: In Study 1, participants in peer- and clinician-led groups showed significantly greater pre-post reductions in risk factors and eating disorder symptoms than controls (M d=.64 and .98 respectively), though clinician- versus peer-led groups had higher attendance and competence ratings, and produced stronger effects at posttest (M d=.32) and at 1-year follow-up (M d=.26). In Study 2, participants in peer-led groups showed greater pre-post reductions in all outcomes than waitlist controls (M d=.75). CONCLUSIONS: Results provide novel evidence that dissonance-based eating disorder prevention groups led by undergraduate peers are feasible and produce greater reductions in eating disorder risk factors and symptoms than minimal-intervention control conditions, but indicate that effects are smaller for peer- versus clinician-led groups.
Subject(s)
Cognitive Dissonance , Feeding and Eating Disorders/prevention & control , Self-Help Groups , Social Support , Adolescent , Adult , Female , Follow-Up Studies , Humans , Peer Group , Pilot Projects , Risk Factors , Students/psychology , Surveys and Questionnaires , Treatment Outcome , Young AdultABSTRACT
Targeted delivery of materials to individual cells remains a challenge in nanoscience and nanomedicine. Near infrared (NIR) laser injection may be a promising alternative to manual injection (where the micropipet diameter limits targeting to small cells) or other laser techniques (such as picosecond green and UV lasers, which can be damaging to cells). However, the efficiency with which NIR pulses can deliver nanoparticles and any adverse effects on living cells needs thorough testing. Toward this end, we have determined the efficacy and toxicity of delivering quantum dots (QDs) into cells of Xenopus laevis embryos by NIR laser injection. Because this model system provides not only living cells but also a developing organism, we were able to assess relatively long-term effects of NIR pulses on embryonic development (through the tadpole stage). We developed parameters for NIR pulses that did not affect embryonic viability or morphology and delivered QDs as effectively as manual injection. Higher intensities of NIR pulses caused permanent damage to the targeted cells, and thus NIR pulses may also prove useful for ablation of specific cells within tissues.
Subject(s)
Embryo, Nonmammalian/metabolism , Lasers , Nanoparticles/administration & dosage , Nanoparticles/adverse effects , Animals , Embryo, Nonmammalian/drug effects , Quantum Dots , Spectroscopy, Near-Infrared , Xenopus laevisABSTRACT
OBJECTIVE: To evaluate the effects of a brief group cognitive-behavioral (CB) depression prevention program for high-risk adolescents with elevated depressive symptoms at 1- and 2-year follow-up. METHOD: In this indicated prevention trial, 341 at-risk youths were randomized to a group CB intervention, group supportive expressive intervention, CB bibliotherapy, or educational brochure control condition. RESULTS: Significantly greater reductions in depressive symptoms were shown by group CB participants relative to brochure control participants by 1-year follow-up and bibliotherapy participants by 1- and 2-year follow-up but not relative to supportive expressive participants. Supportive expressive participants showed greater symptom reduction than CB bibliotherapy participants did at 2-year follow-up. Risk for onset of major or minor depression over the 2-year follow-up was significantly lower for group CB participants (14%; odds ratio = 2.2) and CB bibliotherapy participants (3%; odds ratio = 8.1) than for brochure controls (23%). CONCLUSIONS: Results indicate that this group CB intervention reduces initial symptoms and risk for future depressive episodes, although both supportive expressive therapy and CB bibliotherapy also produce intervention effects that persist long term. Indeed, CB bibliotherapy emerged as the least expensive method of reducing risk for future episodes of depression.
Subject(s)
Bibliotherapy/methods , Cognitive Behavioral Therapy/methods , Depressive Disorder/prevention & control , Psychotherapy, Brief/methods , Adolescent , Analysis of Variance , Depressive Disorder/psychology , Depressive Disorder/therapy , Female , Follow-Up Studies , Humans , Male , Odds Ratio , Risk Factors , Severity of Illness Index , Treatment Outcome , Young AdultABSTRACT
The authors examined the reciprocal relations between rumination and symptoms of depression, bulimia, and substance abuse with longitudinal data from 496 female adolescents. Rumination predicted future increases in bulimic and substance abuse symptoms, as well as onset of major depression, binge eating, and substance abuse. Depressive and bulimic, but not substance abuse, symptoms predicted increases in rumination. Rumination did not predict increases in externalizing symptoms, providing evidence for the specificity of effects of rumination, although externalizing symptoms predicted future increases in rumination. Results suggest rumination may contribute to the etiology of depressive, bulimic, and substance abuse pathology and that the former two disturbances may foster increased rumination. Results imply that it might be beneficial for prevention programs to target this cognitive vulnerability.
Subject(s)
Affect , Bulimia Nervosa/epidemiology , Depression/epidemiology , Personality , Substance-Related Disorders/epidemiology , Adolescent , Female , Humans , Mass Screening , Prevalence , Surveys and QuestionnairesABSTRACT
In this trial, adolescent girls with body dissatisfaction (N = 481, M age = 17 years) were randomized to an eating disorder prevention program involving dissonance-inducing activities that reduce thin-ideal internalization, a prevention program promoting healthy weight management, an expressive writing control condition, or an assessment-only control condition. Dissonance participants showed significantly greater reductions in eating disorder risk factors and bulimic symptoms than healthy weight, expressive writing, and assessment-only participants, and healthy weight participants showed significantly greater reductions in risk factors and symptoms than expressive writing and assessment-only participants from pretest to posttest. Although these effects faded over 6-month and 12-month follow-ups, dissonance and healthy weight participants showed significantly lower binge eating and obesity onset and reduced service utilization through 12-month follow-up, suggesting that both interventions have public health potential.
Subject(s)
Cognitive Dissonance , Feeding and Eating Disorders/prevention & control , Health Status , Adolescent , Feeding and Eating Disorders/psychology , Female , Health Services/statistics & numerical data , Humans , Social Behavior , Treatment OutcomeABSTRACT
This study tested the hypothesis that perceived parenting would show reciprocal relations with adolescents' problem behavior using longitudinal data from 496 adolescent girls. Results provided support for the assertion that female problem behavior has an adverse effect on parenting; elevated externalizing symptoms and substance abuse symptoms predicted future decreases in perceived parental support and control. There was less support for the assertion that parenting deficits foster adolescent problem behaviors; initially low parental control predicted future increases in substance abuse, but not externalizing symptoms, and low parental support did not predict future increases in externalizing or substance abuse symptoms. Results suggest that problem behavior is a more consistent predictor of parenting than parenting is of problem behavior, at least for girls during middle adolescence.
ABSTRACT
Critically ill patients routinely receive H(2) antagonists for stress ulcer prophylaxis while at risk for gastrointestinal bleeding. In these patients it is often difficult to assess accurately the cause of adverse effects such as thrombocytopenia. We evaluate the literature to better define thrombocytopenia related to H(2) antagonist administration and discuss mechanism, potential as a risk factor and case reports describing the severity and duration of thrombocytopenia.