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Abstract Background Low birth weight (LBW,

Abstract Background The incidence of maternal opioid use in the USA has increased substantially since 2000. As a consequence of opioid use during pregnancy, the incidence of neonatal opioid withdrawal syndrome (NOWS) has increased fivefold between 2002 and 2012. Pharmacological therapy is indicated when signs of NOWS cannot be controlled, and the objective of pharmacological therapy is to control NOWS signs. Once pharmacologic therapy has started, there is great variability in strategies to wean infants. An important rationale for studying weaning of pharmacological treatment for NOWS is that weaning represents the longest time interval of drug treatment. Stopping medications too early may not completely treat NOWS symptoms. Methods This will be a pragmatic, randomized, blinded trial of opioid weaning to determine whether more rapid weaning, compared to slow wean, will reduce the number of days of opioid treatment in infants receiving morphine or methadone as the primary treatment for NOWS. Discussion The proposed study is a pragmatic trial to determine whether a rapid-weaning intervention reduces the number of days of opioid treatment, compared to a slow-weaning intervention, and we powered the proposed study to detect a 2-day difference in the length of treatment. Hospitals will be able to use either morphine or methadone with the knowledge that we may find a positive treatment effect for both, one, or neither drugs. Trial registration NCT04214834. Registered January 2, 2020.

BackgroundThe HEALing Communities Study (HCS) included health campaigns as part of a community-engaged intervention to reduce opioid-related overdose deaths in 67 highly impacted communities across Kentucky, Massachusetts, New York, and Ohio. Five campaigns were developed with community input to provide information on opioid use disorder (OUD) and overdose prevention, reduce stigma, and build demand for evidence-based practices (EBPs). An evaluation examined the recognition of campaign messages about naloxone and whether stigma and efficacy beliefs regarding OUD treatment and naloxone changed in HCS intervention communities.MethodsData were collected through surveys offered on Facebook/Instagram to members of communities participating in the HCS intervention and wait-list control communities.ResultsParticipants in HCS intervention communities reported a reduction in stigma regarding OUD and increased efficacy beliefs regarding naloxone associated with recognition of campaign messages. However, this finding is cautiously interpreted as there was no clear evidence for recognition differences between the treatment/control conditions.ConclusionStudy findings indicate associations between campaign message recognition and positive outcomes. Results also highlight possible challenges concerning evaluations of social media campaigns using conventional evaluation techniques.Trial registrationClinicalTrials.gov NCT04111939.

Successful goal directed behavior relies on a human attention system that is flexible and able to adapt to different conditions of physiological stress. However, the effects of physical activity on multiple aspects of selective attention and whether these effects are mediated by aerobic capacity, remains unclear. The aim of the present study was to investigate the effects of a prolonged bout of physical activity on visual search performance and perceptual distraction. Two groups of participants completed a hybrid visual search flanker/response competition task in an initial baseline session and then at 17-minute intervals over a 2 hour 16 minute test period. Participants assigned to the exercise group engaged in steady-state aerobic exercise between completing blocks of the visual task, whereas participants assigned to the control group rested in between blocks. The key result was a correlation between individual differences in aerobic capacity and visual search performance, such that those individuals that were more fit performed the search task more quickly. Critically, this relationship only emerged in the exercise group after the physical activity had begun. The relationship was not present in either group at baseline and never emerged in the control group during the test period, suggesting that under these task demands, aerobic capacity may be an important determinant of visual search performance under physical stress. The results enhance current understanding about the relationship between exercise and cognition, and also inform current models of selective attention.

The load theory of visual attention proposes that efficient selective perceptual processing of task-relevant information during search is determined automatically by the perceptual demands of the display. If the perceptual demands required to process task-relevant information are not enough to consume all available capacity, then the remaining capacity automatically and exhaustively spills-over to task-irrelevant information. The spill-over of perceptual processing capacity increases the likelihood that task-irrelevant information will impair performance. In two visual search experiments, we tested the automaticity of the allocation of perceptual processing resources by measuring the extent to which the processing of task-irrelevant distracting stimuli was modulated by both perceptual load and top-down expectations using behavior, fMRI, and electrophysiology. Expectations were generated by a trial-by-trial cue that provided information about the likely load of the upcoming visual search task. When the cues were valid, behavioral interference was eliminated and the influence of load on frontoparietal and visual cortical responses was attenuated relative to when the cues were invalid. In conditions in which task-irrelevant information interfered with performance and modulated visual activity, individual differences in mean BOLD responses measured from the left intraparietal sulcus were negatively correlated with individual differences in the severity of distraction. These results are consistent with the interpretation that a top-down biasing mechanism interacts with perceptual load to support filtering of task-irrelevant information.

Previous studies have examined the influence of meditation on three functionally different components of attention: executive control, alerting, and orienting. These studies have consistently found that meditation training improves both executive attention and alerting, but there has not been a consistent and clear effect of meditation training on orienting. In addition, while previous studies have shown that the functional coupling of the alerting and executive networks increases the processing of task irrelevant stimuli, it is unknown if participating in a meditation retreat can decouple these components of attention and lead to improved performance. The current study investigated the influence of a week-long intensive meditation retreat on three components of attention by randomly assigning participants to either pre- or postretreat testing groups. A modified attention network test (ANT) was used. Executive attention was measured as the difference in response time between congruent and incongruent task irrelevant flankers (conflict effect). Reflexive and volitional orienting were measured by manipulating cue validity and stimulus onset asynchrony. The coupling of executive attention and alerting was measured by examining flanker interference as a function of the SOA of an alerting cue. The meditation retreat improved task based indices of executive attention, but not reflexive or volitional orienting. There was clear behavioral evidence of coupling between executive attention and alerting in the preretreat group, as the conflict effect peaked when an alerting cue was presented 300 ms before the target. Importantly, there was no increase in the conflict effect for the postretreat group. This is consistent with the notion that the retreat decoupled the executive and alerting networks. These results suggest that previously reported improvements in the executive and alerting networks after meditation training might be mediated by the same underlying mechanism.

Cytosine methylation is an epigenetic modification of DNA catalyzed by DNA methyltransferases. Cytosine methylation of mitochondrial DNA (mtDNA) is believed to have relative underrepresentation; however, possible tissue and cell differences in mtDNA methylation and relationships to neurodegenerative disease have not been examined. We show by immunoblotting that DNA methyltransferase 3A (Dnmt3a) isoform is present in pure mitochondria of adult mouse CNS, skeletal muscle, and testes, and adult human cerebral cortex. Dnmt1 was not detected in adult mouse CNS or skeletal muscle mitochondria but appeared bound to the outer mitochondrial membrane. Immunofluorescence confirmed the mitochondrial localization of Dnmt3a and showed 5-methylcytosine (5mC) immunoreactivity in mitochondria of neurons and skeletal muscle myofibers. DNA pyrosequencing of two loci (D-loop and 16S rRNA gene) and twelve CpG sites in mtDNA directly showed a tissue differential presence of 5mC. Because mitochondria have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS), but the disease mechanisms are uncertain, we evaluated mitochondrial Dnmt3a and 5-methylcytosine levels in human superoxide dismutase-1 (SOD1) transgenic mouse models of ALS. Mitochondrial Dnmt3a protein levels were reduced significantly in skeletal muscle and spinal cord at presymptomatic or early disease. Immunofluorescence showed that 5mC immunoreactivity was present in mitochondria of neurons and skeletal myofibers, and 5mC immunoreactivity became aggregated in motor neurons of ALS mice. DNA pyrosequencing revealed significant abnormalities in 16S rRNA gene methylation in ALS mice. Immunofluorescence showed that 5mC immunoreactivity can be sequestered into autophagosomes and that mitophagy was increased and mitochondrial content was decreased in skeletal muscle in ALS mice. This study reveals a tissue-preferential mitochondrial localization of Dnmt3a and presence of cytosine methylation in mtDNA of nervous ti

The selective processing of goal-relevant information depends on an attention system that can flexibly adapt to changing task demands and expectations. Evidence from visual search tasks indicates that the perceptual selectivity of attention increases when the bottom-up demands of the task increase and when the expectations about task demands engendered by trial history are violated. Evidence from studies of the attentional blink (AB), which measures the temporal dynamics of attention, also indicates that perceptual selectivity during the AB is increased if the bottom-up task demands required are increased. The present work tested whether expectations about task demands engendered by trial history also modulate perceptual selectivity during the AB. Two experiments tested the extent to which inter-trial switches in task demands reduced post-perceptual processing of targets presented during the AB. Experiment 1 indexed post-perceptual processing using the event-related potential (ERP) technique to isolate the context sensitive N400 ERP component evoked by words presented during the AB. Experiment 2 indexed post-perceptual processing using behavioral performance to determine the extent to which personal names survive the AB. The results of both experiments revealed that both electrophysiological (Exp. 1) and behavioral (Exp. 2) indices of post-perceptual processing were attenuated when consecutive trials differed in terms of their perceptual demands. The results are consistent with the notion that the selectivity of attention during the AB is modulated not only by within-trial task demands, but also can be flexibly determined by trial-by-trial expectations.

Transcranial direct current stimulation (tDCS) is an emerging neuromodulation therapy that has been experimentally determined to affect a wide range of behaviors and diseases ranging from motor, cognitive, and memory processes to depression and pain syndromes. The effects of tDCS may be inhibitory or excitatory, depending on the relative polarities of electrodes and their proximity to different brain structures. This distinction is believed to relate to the interaction of current flow with activation thresholds of different neural complexes. tDCS currents are typically applied via a single pair of large electrodes, with one (the active electrode) sited close to brain structures associated with targeted processes. To efficiently direct current toward the areas presumed related to these effects, we devised a method of steering current toward a selected area by reference to a 19-electrode montage applied to a high-resolution finite element model of the head. We used a nonlinear optimization procedure to maximize mean current densities inside the left inferior frontal gyrus, while simultaneously restricting overall current and median current densities within the accumbens. We found that a distributed current pattern could be found that would indeed direct current toward the inferior frontal gyrus in this way, and compared it to other candidate 2-electrode configurations. Further, we found a combination of 4 anterior-posterior electrodes could direct current densities to the accumbens. We conclude that a similar method using multiple electrodes may be a useful means of directing current toward or away from specific brain regions and also of reducing tDCS side effects.

AbstractBackground: Word retrieval during verbal fluency tasks utilizes both automatic and controlled cognitive processes. A distinction has been made between the generation of clusters and switches on verbal fluency tasks. Clusters, or the reporting of contiguous words within semantic or phonemic subcategories, are thought to reflect a relatively automatic processes In contrast, switching from one subcategory to another is thought to represent more controlled, effortful form of cognitive processing. Objective: In this single-blind experiment, we investigated whether tDCS can modify qualitative aspects of verbal fluency, such as clustering and switching, in healthy adults. Methods: Participants were randomly assigned to receive 1mA of either anodal/excitatory or cathodal/inhibitory active tDCS over the left prefrontal cortex in addition to sham stimulation. In the last segment of each 30-minute session, participants completed letter- and category-cued fluency tasks.Results: Anodal tDCS increased both overall productivity and the number and proportion of words in clusters during category-guided verbal fluency, whereas cathodal stimulation produced the opposite effect. Conclusions: tDCS can selectively alter automatic aspects of speeded lexical retrieval in a polarity-dependent fashion during a category-guided fluency task.

Bimolecular fluorescence complementation (BiFC) is based on the complementation between two nonfluorescent fragments of the yellow fluorescent protein (YFP) when they are united by interactions between proteins covalently linked to them. We have successfully applied BiFC in Neurospora crassa using two genes involved in meiotic silencing by unpaired DNA (MSUD) and observed macromolecular complex formation involving only SAD-1 proteins, only SAD-2 proteins, and mixtures of SAD-1 and SAD-2 proteins.

Transposons of the mariner family are widespread in animal genomes and have apparently infected them by horizontal transfer. Most species carry only old defective copies of particular mariner transposons that have diverged greatly from their active horizontally transferred ancestor, while a few contain young, very similar, and active copies. We report here the use of a whole-genome screen in bacteria to isolate somewhat diverged Famar1 copies from the European earwig, Forficula auricularia, that encode functional transposases. Functional and nonfunctional coding sequences of Famar1 and nonfunctional copies of Ammar1 from the European honey bee, Apis mellifera, were sequenced to examine their molecular evolution. No selection for sequence conservation was detected in any clade of a tree derived from these sequences, not even on branches leading to functional copies. This agrees with the current model for mariner transposon evolution that expects neutral evolution within particular hosts, with selection for function occurring only upon horizontal transfer to a new host. Our results further suggest that mariners are not finely tuned genetic entities and that a greater amount of sequence diversification than had previously been appreciated can occur in functional copies in a single host lineage. Finally, this method of isolating active copies can be used to isolate other novel active transposons without resorting to reconstruction of ancestral sequences.

Knowledge of intrachromosomal transpositions has until now been primarily cytological and has been limited to Drosophila and to humans, in both of which segmental shifts can be recognized by altered banding patterns. There has been little genetic information. In this study, we describe the genetic and cytogenetic properties of a transposition in Neurospora crassa. In Tp(IR-->IL)T54M94, a 20 map unit segment of linkage group I has been excised from its normal position and inserted near the centromere in the opposite arm, in inverted order. In crosses heterozygous for the transposition, about one-fifth of surviving progeny are duplications carrying the transposed segment in both positions. These result from crossing over in the interstitial region. There is no corresponding class of progeny duplicated for the interstitial segment. The duplication strains are barren in test crosses. A complementary deficiency class is represented by unpigmented, inviable ascospores. Extent of the duplication was determined by duplication-coverage tests. Orientation of the transposed segment was determined using Tp x Tp crosses heterozygous for markers inside and outside the transposed segment, and position of the insertion relative to the centromere was established using quasi-ordered half-tetrads from crosses x Spore killer. Quelling was observed in the primary transformants that were used to introduce a critical marker into the transposed segment by repeat-induced point mutation (RIP).

In approximately 3% of Neurospora crassa rearrangements, part of a chromosome arm becomes attached to the nucleolus organizer region (NOR) at one end of chromosome 2 (linkage group V). Investigations with one inversion and nine translocations of this type are reported here. They appear genetically to be nonreciprocal and terminal. When a rearrangement is heterozygous, about one-third of viable progeny are segmental aneuploids with the translocated segment present in two copies, one in normal position and one associated with the NOR. Duplications from many of the rearrangements are highly unstable, breaking down by loss of the NOR-attached segment to restore normal chromosome sequence. When most of the rearrangements are homozygous, attenuated strands can be seen extending through the unstained nucleolus at pachytene, joining the translocated distal segment to the remainder of chromosome 2. Although the rearrangements appear genetically to be nonreciprocal, molecular evidence shows that at least several of them are physically reciprocal, with a block of rDNA repeats translocated away from the NOR. Evidence that NOR-associated breakpoints are nonterminal is also provided by intercrosses between pairs of translocations that transfer different-length segments of the same donor-chromosome arm to the NOR.

Chromosome rearrangement In(IL;IR)T(IL;IIIR)SLm-1, has a pericentric inversion in linkage group I associated with a reciprocal translocation between I and III. The rearrangement was identified cytologically in pairing with normal sequence chromosomes at pachynema. Rearrangement breakpoints were mapped genetically in IL, IR and IIIR by crosses with normal sequence strains and in crosses with an inversion that partially overlaps the SLm-1 inversion. When rearrangement SLm-1 is crossed to parents with normal sequence chromosomes, one class among the progeny has a small chromosome deficiency and large duplication. The ascospores containing this deficiency/duplication die either before germination or just after, when growth commences. Germ tubes of the deficiency/duplication progeny, which start to grow then stop, resemble the aborted growth of auxotrophic mutants germinated on minimal medium. Efforts to correct the deficiency with nutritional supplements were not successful. However, the defective class can be rescued by fusing the germinating hyphae of the deficiency ascospore with a complementary auxotrophic mutant to form a heterokaryon. A deficiency/duplication nucleus that is rescued in a heterokaryon can serve as a fertilizing nucleus in crosses with a normal sequence parent. One half of their progeny have the normal chromosome sequence and one half have the chromosome deficiency syndrome and die at germination.

In translocation T (IL leads to VL) OY321 of Neurospora crassa a distal portion of the nucleolus organizer chromosome, including ribosomal DNA sequences and the nucleolus satellite, is interchanged with a long terminal segment of IL. When OY321 is crossed by Normal sequence, one-fourth of the meiotic products are segmental aneuploids that contain two copies of the long IL segment and that are deficient for the distal portion of the organizer. Each such product forms a nucleolus and is viable. The complementary aneuploid products are deficient for the IL segment and are therefore inviable. - In crosses of OY321 X OY321, each product is capable of making two nucleoli; nucleoli formed by the separated nucleolus organizer parts usually fuse, but most 8-spored asci contain some nuclei in which two separate nucleoli can be seen. One nucleolus is then terminal on its chromosome while the second is interstitial and somewhat smaller. - In crosses of OY321 X Normal, half of the meiotic products are capable of making two nucleoli. However, only about 15% of 8-spored asci have one or more nuclei containing separate nucleoli. At pachytene and later in prophase I, the single fusion nucleolus is associated with three bivalent chromosome segments. Each nucleus of every ascus contains at least one nucleolus, even in asci where some nuclei display two nucleoli. - Crosses of Aneuploid X Normal are usually semibarren, producing a reduced number of ascospores, some of which are inviable. Some aneuploid cultures become fully fertile by reverting to a quasinormal sequence lacking a satellite. In some crosses of Aneuploid X Normal, individual asci may show at prophase I either complete loss, partial loss, or pycnosis of the translocated IL segment. This observation of pycnosis suggests chromosome inactivation. - Growth from aneuploid ascospores is initially slow, but can accelerate to the wild-type rate.

In translocation OY321 of Neurospora crassa, the nucleolus organizer is divided into two segments, a proximal portion located interstitially in one interchange chromosome, and a distal portion now located terminally on another chromosome, linkage group I. In crosses of Translocation X Translocation, exceptional progeny are recovered nonselectively in which the chromosome sequence has apparently reverted to Normal. Genetic, cytological, and molecular evidence indicates that reversion is the result of meiotic crossing over between homologous displaced rDNA repeats. Marker linkages are wild type in these exceptional progeny. They differ from wild type, however, in retaining an interstitial block of rRNA genes which can be demonstrated cytologically by the presence of a second, small interstitial nucleolus and genetically by linkage of an rDNA restriction site polymorphism to the mating-type locus in linkage group I. The interstitial rDNA is more highly methylated than the terminal rDNA. The mechanism by which methylation enzymes distinguish between interstitial rDNA and terminal rDNA is unknown. Some hypotheses are considered.

In rearrangement T(VL leads to IVL)AR33 the segment of chromosome 2 bearing the nucleolus organizer is translocated to the end of chromosome 4. When AR33 is crossed by Normal sequence (N), one third of the viable progeny contain a stable nontandem duplication with two organizers per nucleus. The organizer-deficient complementary products are inviable. Chromosomes and nucleoli have been examined during meiosis and postmeiotic nuclear divisions in the ascus, comparing heterozygous AT33 X N crosses with N X N and with crosses heterozygous for other interchanges. When AR33 is heterozygous, asci are of three types having the nucleolus organizer dupliciated in 0, 1 or 2 of the meiotic products. Frequencies of the ascus types are as expected from the known positions of rearrangement break points. Nucleoli formed by two organizers frequently fuse. Deficiency nuclei that contain no nucleolus organizer may form one or more small nucleolus-like bodies.

Cytological study of meiotic chromosomes heterozygous for the T(I-->II)39311 translocation confirm genetic evidence (Perkins 1972) that a section of linkage group I including the mating type locus has been inserted into linkage group II. Pachytene chromosomes when fully paired show that a segment from chromosome 1 has been inserted into chromosome 6. When pairing fails between the translocated segment in 6 and its homologous region in chromosome 1, buckles or loops are formed at pachynema in the deletion or insertion areas of the bivalents.-Acentric fragments and anaphase bridges occur at both meiotic divisions and in the subsequent two mitotic divisions in the ascus. These provide supporting evidence that the translocated segment is inverted with respect to centromere in its new location.-Unexpectedly the acentric fragment, formed by crossing over in the inverted translocated segment, persists without degradation in a micronucleus, and it replicates and divides in synchrony with the centric chromosomes in adjacent nuclei.