Proteolysis by the ubiquitin-proteasome pathway appears to have a complex role in synaptic plasticity, but its various functions remain to be elucidated. Using late phase long-term potentiation ...(L-LTP) in the hippocampus of the mouse as a model for long-term synaptic plasticity, we previously showed that inhibition of the proteasome enhances induction but blocks maintenance of L-LTP. In this study, we investigated the possible mechanisms by which proteasome inhibition has opposite effects on L-LTP induction and maintenance. Our results show that inhibiting phosphatidyl inositol-3 kinase or blocking the interaction between eukaryotic initiation factors 4E (eIF4E) and 4G (eIF4G) reduces the enhancement of L-LTP induction brought about by proteasome inhibition suggesting interplay between proteolysis and the signaling pathway mediated by mammalian target of rapamycin (mTOR). Also, proteasome inhibition leads to accumulation of translational activators in the mTOR pathway such as eIF4E and eukaryotic elongation factor 1A (eEF1A) early during L-LTP causing increased induction. Furthermore, inhibition of the proteasome causes a buildup of translational repressors, such as polyadenylate-binding protein interacting protein 2 (Paip2) and eukaryotic initiation factor 4E-binding protein 2 (4E-BP2), during late stages of L-LTP contributing to the blockade of L-LTP maintenance. Thus, the proteasome plays a critical role in regulating protein synthesis during L-LTP by tightly controlling translation. Our results provide novel mechanistic insights into the interplay between protein degradation and protein synthesis in long-term synaptic plasticity.
Multispectral fluorescence imaging coupled with linear unmixing is a form of image data collection and analysis that allows for measuring multiple molecular signals in a single biological sample. ...Multiple fluorescent dyes, each measuring a unique molecule, are simultaneously measured and subsequently "unmixed" to provide a read-out for each molecular signal. This strategy allows for measuring highly multiplexed signals in a single data capture session, such as multiple proteins or RNAs in tissue slices or cultured cells, but can often result in mixed signals and bleed-through problems across dyes. Existing spectral unmixing algorithms are not optimized for challenging biological specimens such as post-mortem human brain tissue, and often require manual intervention to extract spectral signatures. We therefore developed an intuitive, automated, and flexible package called SUFI: spectral unmixing of fluorescent images.
This package unmixes multispectral fluorescence images by automating the extraction of spectral signatures using vertex component analysis, and then performs one of three unmixing algorithms derived from remote sensing. We evaluate these remote sensing algorithms' performances on four unique biological datasets and compare the results to unmixing results obtained using ZEN Black software (Zeiss). We lastly integrate our unmixing pipeline into the computational tool dotdotdot, which is used to quantify individual RNA transcripts at single cell resolution in intact tissues and perform differential expression analysis, and thereby provide an end-to-end solution for multispectral fluorescence image analysis and quantification.
In summary, we provide a robust, automated pipeline to assist biologists with improved spectral unmixing of multispectral fluorescence images.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The proteasome is a structural complex of many proteins that degrades substrates marked by covalent linkage to ubiquitin. Many years of research has shown a role for ubiquitin-proteasome-mediated ...proteolysis in synaptic plasticity and memory mainly in degrading synaptic, cytoplasmic and nuclear proteins. Recent work indicates that the proteasome has wider proteolytic and non-proteolytic roles in processes such as histone modifications that affect synaptic plasticity and memory. In this review, we assess the evidence gathered from neuronal as well as non-neuronal cell types regarding the function of the proteasome in positive or negative regulation of posttranslational modifications of histones, such as acetylation, methylation and ubiquitination. We discuss the critical roles of the proteasome in clearing excess histone proteins in various cellular contexts and the possible non-proteolytic functions in regulating transcription of target genes. In addition, we summarize the current literature on diverse chromatin-remodeling machineries, such as histone acetyltransferases, deacetylates, methyltransferases and demethylases, as targets for proteasomal degradation across experimental models. Lastly, we provide a perspective on how proteasomal regulation of histone modifications may modulate synaptic plasticity in the nervous system.
In this study, we compared particulate matter (PM) measurements (including PM
10
, PM
2.5
, heavy metals, and black carbon) between the 2014 rainy season (August–October) and dry season (March–May) ...in different urban areas within Ho Chi Minh City, Vietnam. PM
10
and PM
2.5
concentrations varied widely among the sampling sites during each season, with relative PM concentrations increasing in the following order: city zoo < rural area < residential area < roadside < city road. Higher PM
10
and PM
2.5
concentrations observed on roads and at roadsides were strongly correlated with vehicle activity. Heavy metals were found to be important atmospheric PM components ranged from 131.77 ± 42.13 to 233.13 ± 79.88 µg m
−3
. Changes in black carbon concentration in Ho Chi Minh City may have been related to changes in meteorological conditions and may in turn influence ambient air quality. These results provide useful reference information for urban development planning and environmental policy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human ...populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters.
Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii, Rickettsia parkeri, Rickettsia bellii, Rickettsia rhipicephali and Rickettsia amblyommatis. Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A. sculptum, A. brasiliense and A. aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp.
A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum, 910/1,584 (57.4%) as Amblyomma brasiliense, 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum. All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A. sculptum. No tested tick was positive by standard PCR to SFG Rickettsia spp.
The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Inland salt marshes are rare habitats in the Great Lakes region of North America, formed on salt deposits from the Silurian period. These patchy habitats are abiotically stressful for the freshwater ...invertebrates that live there, and provide an opportunity to study the relationship between stress and diversity. We used morphological and COI metabarcoding data to assess changes in diversity and composition across both space (a transect from the salt seep to an adjacent freshwater area) and time (three sampling seasons). Richness was significantly lower at the seep site with both datatypes, while metabarcoding data additionally showed reduced richness at the freshwater transect end, consistent with a pattern where intermediate levels of stress show higher diversity. We found complementary, rather than redundant, patterns of community composition using the two datatypes: not all taxa were equally sequenced with the metabarcoding protocol. We identified taxa that are abundant at the salt seep of the marsh, including biting midges (Culicoides) and ostracods (Heterocypris). We conclude that (as found in other studies) molecular and morphological work should be used in tandem to identify the biodiversity in this rare habitat. Additionally, salinity may be a driver of community membership in this system, though further ecological research is needed to rule out alternate hypotheses.
Inland salt marshes are rare habitats in the Great Lakes region of North America, formed on salt deposits from the Silurian period. We used morphological and COI metabarcoding data to assess changes in diversity and composition across both space (a transect from the salt seep to an adjacent freshwater area) and time (three sampling seasons). Community composition was different with different datatypes. Diversity and richness were lowest at the salt seep regardless of datatype.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Static load test program was performed on a single pile and two 16-pile groups with equal and different pile lengths. The soil profile consists of sand fill to 0.5 m depth placed on a thick deposit ...of soft, normally consolidated and compressible clay. The closed end steel pipe piles in 60 mm diameter were installed from 1.5 m through 2.1 m depth within soft clay deposit. The center-to-center distance of piles in group is about 3 times of pile diameter. The strain gages were installed at one level above and two through four levels below ground surface. Tests were carried out about 7 days after driving by method of a series of load increments placed every 5-min until plunging failure occurred. The load at plunging failure for the single pile, the equal-length pile group and the different-length pile group were about 3, 40 and 48 kN, respectively. The movements at start of failure were about 12, 18, and 17 mm, respectively. The analysis of strain gage measurements indicates that the load distribution on piles in the different-length pile group has become significantly uniform.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The expression of genetic material governs brain development, differentiation, and function, and targeted manipulation of gene expression is required to understand contributions of gene function to ...health and disease states. Although recent improvements in CRISPR/dCas9 interference (CRISPRi) technology have enabled targeted transcriptional repression at selected genomic sites, integrating these techniques for use in non-dividing neuronal systems remains challenging. Previously, we optimized a dual lentivirus expression system to express CRISPR-based activation machinery in post-mitotic neurons. Here we used a similar strategy to adapt an improved dCas9-KRAB-MeCP2 repression system for robust transcriptional inhibition in neurons. We find that lentiviral delivery of a dCas9-KRAB-MeCP2 construct driven by the neuron-selective human synapsin promoter enabled transgene expression in primary rat neurons. Next, we demonstrate transcriptional repression using CRISPR sgRNAs targeting diverse gene promoters, and show superiority of this system in neurons compared to existing RNA interference methods for robust transcript specific manipulation at the complex Brain-derived neurotrophic factor (
Bdnf
) gene. Our findings advance this improved CRISPRi technology for use in neuronal systems for the first time, potentially enabling improved ability to manipulate gene expression states in the nervous system.
The main source of knowledge on adverse drug events (ADE) are physicians' reports in controlled clinical trials. In contrast, little is known about the parents' perception of ADE of anticonvulsants ...their children receive.
After approval by the local ethics committee, we performed a survey in a neuropediatric outpatient clinic of a university hospital. Based on a structured questionnaire, we interviewed parents of children with current anticonvulsant treatment regarding (i) their fears about potential ADE, (ii) experienced ADE according to parents, and (iii) implications of ADE on the child's life.
Parents of 150 patients took part in the interview. (i) 95 (63.3%) parents expressed fears concerning ADE, mostly liver injury/liver failure (33 22%). (ii) 129 (86%) parents reported experienced ADE, mostly sedation (65 43.3%) and abnormal behavior (54 36%). (iii) Parents reported substantial implications of ADE on the child's daily life for 84 (56%) children, and 63 (42%) parents expressed a negative impact on the child's development.
We recognized a great discrepancy between those ADE that were feared and those that were experienced. Parents feared life-threatening ADE and experienced less severe ADE that nevertheless have a negative impact on the child's daily life.
•63% parents feared adverse drug events of their children's anticonvulsants.•Adverse drug events mostly feared concern liver and kidney function.•86% parents reported experienced adverse drug events caused by anticonvulsants.•Adverse drug events mostly experienced were sedation and abnormal behavior.•56% reported substantial implications of adverse drug events on the child's life.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Background
Prenatal/postnatal exposure to insecticides has been linked to developmental disorders in adulthood. Chlorpyrifos (CPF) is a widely used organophosphorus acetylcholinesterase ...(AChE)‐inhibiting insecticide. The present study established whether prenatal and postnatal exposure to CPF is associated with intestinal motor dysfunction in adult rats.
Methods
Three groups of pregnant rats were exposed to either CPF (1 or 5 mg/kg/day; the CPF1 and CPF5 groups) or vehicle (the control group) by gavage from gestational day 1 until weaning. At weaning, the pups were separated from their dams and individually gavaged (with the same dose) until postnatal day 60. We then measured in vivo intestinal transit and the in vitro contractile responses of ileal smooth muscle strips to electrical field stimulation. Expression of inducible nitric oxide synthase (iNOS) in the ileum was determined using qRT‐PCR and immunoblots. Morphometry and AChE assays were also performed.
Key Results
At adulthood, the mean body mass was lower in the CPF1 and CPF5 groups than in controls. CPF5 exposure was associated with weaker in vitro contraction of ileal muscle strips, which was reversed by adding the NOS inhibitor (L‐NAME). There was no significant intergroup difference in the mean in vivo transit time. Exposure to CPF was associated with greater iNOS expression, lower AChE activity and reduced circular and longitudinal smooth muscle thickness.
Conclusions & Inferences
Prenatal and postnatal exposure to CPF in the rat is associated with weaker contraction of ileal longitudinal smooth muscle via a nitrergic mechanism with increased iNOS expression.
The present study showed that the exposure to chlorpyrifos (CPF), a widely used insecticide, from the first day of gestation to early adulthood, in a rat model, is associated with low EFS‐induced ileal contraction, elevated iNOS expression, partial inhibition of AChE activity, and low ileal muscle thickness.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
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