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Disruption of sleep and circadian rhythms are a comorbid feature of many pathologies, and can negatively influence many health conditions, including neurodegenerative disease, metabolic illness, cancer, and various neurological disorders. Genetic association studies linking sleep and circadian disturbances with disease susceptibility have mainly focused on changes in gene expression due to mutations, such as single-nucleotide polymorphisms. The interaction between sleep and/or circadian rhythms with the use of Alternative Polyadenylation (APA) has been largely undescribed, particularly in the context of other disorders. APA is a process that generates various transcript isoforms of the same gene affecting its mRNA translation, stability, localization, and subsequent function. Here we identified unique APAs expressed in rat brain over time-of-day, immediately following sleep deprivation, and the subsequent recovery period. From these data, we performed a secondary analysis of these sleep- or time-of-day associated PASs with recently described APA-linked human brain disorder susceptibility genes., Competing Interests: Competing Interests J.G. is the founder of Blood Brain Biotechnology, LLC and a member of its scientific advisory board. Jon Davis is a principal scientist at Integrated Physiology Research, Novo Nordisk. All other authors declare no competing interests.

Sleep and circadian rhythms are observed broadly throughout animal phyla and influence neural plasticity and cognitive function. However, the few phylogenetically conserved cellular and molecular pathways that are implicated in these processes are largely focused on neuronal cells. Research on these topics has traditionally segregated sleep homeostatic behavior from circadian rest-activity rhythms. Here we posit an alternative perspective, whereby mechanisms underlying the integration of sleep and circadian rhythms that affect behavioral state, plasticity, and cognition reside within glial cells. The brain-type fatty acid binding protein, FABP7, is part of a larger family of lipid chaperone proteins that regulate the subcellular trafficking of fatty acids for a wide range of cellular functions, including gene expression, growth, survival, inflammation, and metabolism. FABP7 is enriched in glial cells of the central nervous system and has been shown to be a clock-controlled gene implicated in sleep/wake regulation and cognitive processing. FABP7 is known to affect gene transcription, cellular outgrowth, and its subcellular localization in the fine perisynaptic astrocytic processes (PAPs) varies based on time-of-day. Future studies determining the effects of FABP7 on behavioral state- and circadian-dependent plasticity and cognitive processes, in addition to functional consequences on cellular and molecular mechanisms related to neural-glial interactions, lipid storage, and blood brain barrier integrity will be important for our knowledge of basic sleep function. Given the comorbidity of sleep disturbance with neurological disorders, these studies will also be important for our understanding of the etiology and pathophysiology of how these diseases affect or are affected by sleep., Competing Interests: JG was founder of Blood Brain Biotechnology, LLC. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gerstner, Flores, Lefton, Rogers and Davis.)

Fatty acid binding proteins (FABPs) are a family of intracellular lipid chaperone proteins known to play critical roles in the regulation of fatty acid uptake and transport as well as gene expression. Brain-type fatty acid binding protein (FABP7) is enriched in astrocytes and has been implicated in sleep/wake regulation and neurodegenerative diseases; however, the precise mechanisms underlying the role of FABP7 in these biological processes remain unclear. FABP7 binds to both arachidonic acid (AA) and docosahexaenoic acid (DHA), resulting in discrete physiological responses. Here, we propose a dichotomous role for FABP7 in which ligand type determines the subcellular translocation of fatty acids, either promoting wakefulness aligned with Alzheimer's pathogenesis or promoting sleep with concomitant activation of anti-inflammatory pathways and neuroprotection. We hypothesize that FABP7-mediated translocation of AA to the endoplasmic reticulum of astrocytes increases astrogliosis, impedes glutamatergic uptake, and enhances wakefulness and inflammatory pathways via COX-2 dependent generation of pro-inflammatory prostaglandins. Conversely, we propose that FABP7-mediated translocation of DHA to the nucleus stabilizes astrocyte-neuron lactate shuttle dynamics, preserves glutamatergic uptake, and promotes sleep by activating anti-inflammatory pathways through the peroxisome proliferator-activated receptor-γ transcriptional cascade. Importantly, this model generates several testable hypotheses applicable to other neurodegenerative diseases, including amyotrophic lateral sclerosis and Parkinson's disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Needham, Torpey, Flores, Davis, Vanderheyden and Gerstner.)

Humans with post-traumatic stress disorder (PTSD) exhibit sleep disturbances that include insomnia, nightmares, and enhanced daytime sleepiness. Sleep disturbances are considered a hallmark feature of PTSD; however, little is known about the cellular and molecular mechanisms regulating trauma-induced sleep disorders. Using a rodent model of PTSD called "Single Prolonged Stress" (SPS) we examined the requirement of the brain-type fatty acid binding protein Fabp7, an astrocyte expressed lipid-signaling molecule, in mediating trauma-induced sleep disturbances. We measured baseline sleep/wake parameters and then exposed Fabp7 knock-out (KO) and wild-type (WT) C57BL/6N genetic background control animals to SPS. Sleep and wake measurements were obtained immediately following the initial trauma exposure of SPS, and again 7 days later. We found that active-phase (dark period) wakefulness was similar in KO and WT at baseline and immediately following SPS; however, it was significantly increased after 7 days. These effects were opposite in the inactive-phase (light period), where KOs exhibited increased wake in baseline and following SPS, but returned to WT levels after 7 days. To examine the effects of Fabp7 on unconditioned anxiety following trauma, we exposed KO and WT mice to the light-dark box test before and after SPS. Prior to SPS, KO and WT mice spent similar amounts of time in the lit compartment. Following SPS, KO mice spent significantly more time in the lit compartment compared to WT mice. These results demonstrate that mutations in an astrocyte-expressed gene ( Fabp7 ) influence changes in stress-dependent sleep disturbances and associated anxiety behavior., Competing Interests: Conflicts of Interest: The authors declare no conflict of interest.

The cellular consequences of sleep loss are poorly characterized. In the pyramidal neurons of mouse frontal cortex, we found that mitochondria and secondary lysosomes occupy a larger proportion of the cytoplasm after chronic sleep restriction compared to sleep, consistent with increased cellular burden due to extended wake. For each morphological parameter, the within-animal variance was high, suggesting that the effects of sleep and sleep loss vary greatly among neurons. However, the analysis was based on 4-5 mice/group and a single section/cell. Here, we applied serial block-face scanning electron microscopy to identify signatures of sleep and sleep loss in the Drosophila brain. Stacks of images were acquired and used to obtain full 3D reconstructions of the cytoplasm and nucleus of 263 Kenyon cells from adult flies collected after a night of sleep (S) or after 11 h (SD11) or 35 h (SD35) of sleep deprivation (9 flies/group). Relative to S flies, SD35 flies showed increased density of dark clusters of chromatin and Golgi apparata and a trend increase in the percent of cell volume occupied by mitochondria, consistent with increased need for energy and protein supply during extended wake. Logistic regression models could assign each neuron to the correct experimental group with good accuracy, but in each cell, nuclear and cytoplasmic changes were poorly correlated, and within-fly variance was substantial in all experimental groups. Together, these results support the presence of ultrastructural signatures of sleep and sleep loss but underscore the complexity of their effects at the single-cell level., (© Sleep Research Society 2021. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Parkinson's Disease (PD) is the most common movement disorder, and the strongest genetic risk factor for PD is mutations in the glucocerebrosidase gene ( GBA ). Mutations in GBA also lead to the development of Gaucher Disease (GD), the most common type of lysosomal storage disorder. Current therapeutic approaches fail to address neurological GD symptoms. Therefore, identifying therapeutic strategies that improve the phenotypic traits associated with GD/PD in animal models may provide an opportunity for treating neurological manifestations of GD/PD. Thiazolidinediones (TZDs, also called glitazones) are a class of compounds targeted for the treatment of type 2 diabetes, and have also shown promise for the treatment of neurodegenerative disease, including PD. Here, we tested the efficacy of glitazone administration during development in a fly GD model with deletions in the GBA homolog, dGBA1b (GBA1 ΔTT/ΔTT ). We observed an optimal dose of pioglitazone (PGZ) at a concentration of 1 μM that reduced sleep deficits, locomotor impairments, climbing defects, and restoration of normal protein levels of Ref(2)P, a marker of autophagic flux, in GBA1 ΔTT/ΔTT mutant flies, compared to GBA1 +/+ control flies. These data suggest that PGZ may represent a potential compound with which to treat GD/PD by improving function of lysosomal-autophagy pathways, a cellular process that removes misfolded or aggregated proteins.

The astrocyte brain-type fatty-acid binding protein (Fabp7) circadian gene expression is synchronized in the same temporal phase throughout mammalian brain. Cellular and molecular mechanisms that contribute to this coordinated expression are not completely understood, but likely involve the nuclear receptor Rev-erbα (NR1D1), a transcriptional repressor. We performed ChIP-seq on ventral tegmental area (VTA) and identified gene targets of Rev-erbα, including Fabp7 . We confirmed that Rev-erbα binds to the Fabp7 promoter in multiple brain areas, including hippocampus, hypothalamus, and VTA, and showed that Fabp7 gene expression is upregulated in Rev-erbα knock-out mice. Compared to Fabp7 mRNA levels, Fabp3 and Fabp5 mRNA were unaffected by Rev-erbα depletion in hippocampus, suggesting that these effects are specific to Fabp7 . To determine whether these effects of Rev-erbα depletion occur broadly throughout the brain, we also evaluated Fabp mRNA expression levels in multiple brain areas, including cerebellum, cortex, hypothalamus, striatum, and VTA in Rev-erbα knock-out mice. While small but significant changes in Fabp5 mRNA expression exist in some of these areas, the magnitude of these effects are minimal to that of Fabp7 mRNA expression, which was over 6-fold across all brain regions. These studies suggest that Rev-erbα is a transcriptional repressor of Fabp7 gene expression throughout mammalian brain.

Ageing typically leads to various memory deficits which results in older adults' tendency to remember more general information and rely on gist memory. The current study examined if younger and older adults could remember which of two comparable grocery items (e.g., two similar but different jams) was paired with a lower price (the "better buy"). Participants studied lists of grocery items and their prices, in which the two items in each category were presented consecutively (Experiment 1), or separated by intervening items (Experiment 2). At test, participants were asked to identify the "better buy" and recall the price of both items. There were negligible age-related differences for the "better buy" in Experiment 1, but age-related differences were present in Experiment 2 when there were greater memory demands involved in comparing the two items. Together, these findings suggest that when price information of two items can be evaluated and compared within a short period of time, older adults can form stable gist-based memory for prices, but that this is impaired with longer delays. We relate the findings to age-related changes in the use of gist and verbatim memory when remembering prices, as well as the associative deficit account of cognitive ageing.

Older adults often experience associative memory impairments but can sometimes remember important information. The current experiments investigate potential age-related similarities and differences associate memory for gains and losses. Younger and older participants were presented with faces and associated dollar amounts, which indicated how much money the person "owed" the participant, and were later given a cued recall test for the dollar amount. Experiment 1 examined face-dollar amount pairs while Experiment 2 included negative dollar amounts to examine both gains and losses. While younger adults recalled more information relative to older adults, both groups were more accurate in recalling the correct value associated with high-value faces compared to lower-value faces and remembered gist-information about the values. However, negative values (losses) did not have a strong impact on recall among older adults versus younger adults, illustrating important associative memory differences between younger and older adults.

Objectives: To describe the new drugs marketed in Brazil during the period 2000-2004, compare the description to the country's burden of disease, and suggest initiatives capable of addressing the situation from the perspective of a developing country., Methods: Records of new drugs were surveyed in an official drug registration database. The new drugs were categorized by Anatomical Therapeutic Chemical classification, indication, and innovation, and compared with the needs of the country's burden of disease. Data on the morbidity and mortality rates of selected diseases (diabetes, Hansen's disease, hypertension, tuberculosis) were retrieved from official documents and the literature., Results: During the period investigated, 109 new drugs were launched. Most were general anti-infectives for systemic use (19), followed by antineoplastic and immunomodulating agents (16). The number of new drugs launched in 2004 was roughly one-third that of 2000. Of 65 new drugs, only one-third can be classified as innovative. Most new drugs were intended to treat noninfectious diseases that typically affect developed countries, diseases that constitute only a fraction of the country's challenges., Conclusions: A mismatch occurs between public health needs and the new drugs launched on the Brazilian market. Not only did the number of new drugs decrease in the study period, but only a few were actually new in therapeutic terms. Developing countries must acquire expertise in research and development to strengthen their capacity to innovate and produce the drugs they need.

Double-strand DNA breaks can be repaired by any of several alternative mechanisms that differ greatly in the nature of the final repaired products. We used a reporter construct, designated "Repair reporter 3" (Rr3), to measure the relative usage of these pathways in Drosophila germ cells. The method works by creating a double-strand break at a specific location such that expression of the red fluorescent protein, DsRed, in the next generation can be used to infer the frequency at which each pathway was used. A key feature of this approach is that most data come from phenotypic scoring, thus allowing large sample sizes and considerable precision in measurements. Specifically, we measured the proportion of breaks repaired by (1) conversion repair, (2) nonhomologous end joining (NHEJ), or (3) single-strand annealing (SSA). For conversion repair, the frequency of mitotic crossing over in the germ line indicates the relative prevalence of repair by double Holliday junction (DHJ) formation vs. the synthesis-dependent strand annealing (SDSA) pathway. We used this method to show that breaks occurring early in germ-line development were much more frequently repaired via single-strand annealing and much less likely to be repaired by end joining compared with identical breaks occurring later in development. Conversion repair was relatively rare when breaks were made either very early or very late in development, but was much more frequent in between. Significantly, the changes in relative usage occurred in a compensatory fashion, such that an increase in one pathway was accompanied by decreases in others. This negative correlation is interpreted to mean that the pathways for double-strand break repair compete with each other to handle a given breakage event.

The bacterial transposon Tn7 encodes five trans-acting transposition genes, tnsA, B, C, D, and E. Tn7 requires four of these genes, tnsA, B, C, and D, for a novel transposition pathway: high-efficiency site-specific transposition to a chromosomal attachment site, attTn7. Plasmids that individually allow inducible overexpression of proteins from the first initiation codon of four of these genes were constructed. Escherichia coli strains carrying these plasmids were used to overexpress the TnsA, B, C, and D proteins. The abundance and the apparent relative molecular mass of these proteins were examined and the latter was compared to those predicted from wild-type Tn7. The functionality of these proteins, encoded by an overexpression construct, was demonstrated by the fact that they could efficiently trans-complement a defective mini-Tn7 carrying only the cis-essential Tn7 termini in an in vivo assay for transposition to attTn7.

The authors present 11,074 patients with head trauma managed in the Xoco and Juarez Hospitals from Mexico City, from 1980 through 1990. They report a frequency of cerebrospinal fluid fistulas in 1.3% of head trauma: 55% were anterior fossa fistulas and 39% middle fossa fistulas. The most common symptoms and the treatment are presented.

The large (14 kb; kb = 10(3) bases) bacterial transposon, Tn7 (encoding resistance to trimethoprim and streptomycin/spectinomycin), has unusual properties. Like other elements, Tn7 transposes with low efficiency and low target-site specificity, but Tn7 also transposes, with high frequency in a unique orientation, to a preferred "attachment" site, called attTn7, in the Escherichia coli chromosome and similarly into plasmids containing attTn7. We developed a novel bacteriophage M13-based assay system to measure the transposition frequency of Tn7 to M13mp phage vectors containing attTn7 on a cloned 1 kb fragment of chromosomal DNA. Phage harvested from a Tn7 donor strain were used to infect recipient bacteria with selection for trimethoprim resistance. Transposition frequency, expressed as the number of trimethoprim-resistant colonies per plaque-forming unit, was found to be approximately 10(-4) to M13mp::attTn7, in contrast to 10(-10) to M13mp recombinants with approximately 1 kb insertions of other, "generic brand", DNA. By deletion analysis of M13mp::attTn7, we show that attTn7 is contained within a 64 base-pair region; sequences adjacent to the actual insertion site and encoding the carboxy terminus of the glmS gene are required. This assay also provided evidence for transposition immunity conferred by the right end of Tn7.