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1.
Am J Hum Genet ; 106(5): 717-725, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32330417

RESUMO

We identified three unrelated individuals with de novo missense variants in CDK19, encoding a cyclin-dependent kinase protein family member that predominantly regulates gene transcription. These individuals presented with hypotonia, global developmental delay, epileptic encephalopathy, and dysmorphic features. CDK19 is conserved between vertebrate and invertebrate model organisms, but currently abnormalities in CDK19 are not known to be associated with a human disorder. Loss of Cdk8, the fly homolog of CDK19, causes larval lethality, which is suppressed by expression of human CDK19 reference cDNA. In contrast, the CDK19 p.Tyr32His and p.Thr196Ala variants identified in the affected individuals fail to rescue the loss of Cdk8 and behave as null alleles. Additionally, neuronal RNAi-mediated knockdown of Cdk8 in flies results in semi-lethality. The few eclosing flies exhibit severe seizures and a reduced lifespan. Both phenotypes are fully suppressed by moderate expression of the CDK19 reference cDNA but not by expression of the two variants. Finally, loss of Cdk8 causes an obvious loss of boutons and synapses at larval neuromuscular junctions (NMJs). Together, our findings demonstrate that human CDK19 fully replaces the function of Cdk8 in the fly, the human disease-associated CDK19 variants behave as strong loss-of-function variants, and deleterious CDK19 variants underlie a syndromic neurodevelopmental disorder.


Assuntos
Encefalopatias/genética , Quinases Ciclina-Dependentes/genética , Epilepsia Generalizada/genética , Deficiência Intelectual/genética , Mutação de Sentido Incorreto/genética , Adulto , Sequência de Aminoácidos , Animais , Pré-Escolar , Quinase 8 Dependente de Ciclina/deficiência , Quinase 8 Dependente de Ciclina/genética , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Junção Neuromuscular , Doenças Raras/genética , Convulsões/genética , Síndrome , Adulto Jovem
2.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37974046

RESUMO

AIMS: The objectives of this study were to evaluate the effect of combination treatment with cold plasma (CP), vacuum packaging (VP), and hot water (HW) on the inactivation of foodborne pathogens on buckwheat seeds, and determined the germination rates of seeds and the quality of sprouts following combination treatment. METHODS AND RESULTS: Buckwheat seeds inoculated with Salmonella Typhimurium and Listeria monocytogenes were treated with CP, HW, CP + HW, VP + HW, or CP + VP + HW. The germination rates of the HW-, CP + HW-, VP + HW-, and CP + VP + HW-treated seeds and the antioxidant activities and rutin contents of the CP + HW- and CP + VP + HW-treated sprouts were determined. HW, CP + HW, and CP + VP + HW were found to reduce the levels of the two pathogens to below the detection limit (1.0 log CFU g-1) at 70°C. However, HW and CP + HW significantly reduced the germination rate of buckwheat seeds. CP + VP + HW did not affect the germination rate of seeds nor the antioxidant activities and rutin content of buckwheat sprouts. CONCLUSIONS: These results indicate that CP + VP + HW can be used as a novel control method to reduce foodborne pathogens in seeds without causing quality deterioration.


Assuntos
Fagopyrum , Listeria monocytogenes , Salmonella typhimurium , Vácuo , Antioxidantes , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Água , Sementes , Rutina/farmacologia , Germinação
3.
Int J Mol Sci ; 24(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37895006

RESUMO

Previously, we demonstrated that mitochondrial transplantation has beneficial effects in a polymicrobial sepsis model. However, the mechanism has not been fully investigated. Mitochondria have their own genes, and genomic changes in sepsis are an important issue in terms of pathophysiology, biomarkers, and therapeutic targets. To investigate the changes in transcriptomic features after mitochondrial transplantation in a polymicrobial sepsis model, we used a rat model of fecal slurry polymicrobial sepsis. Total RNA from splenocytes of sham-operated (SHAM, n = 10), sepsis-induced (SEPSIS, n = 7), and sepsis receiving mitochondrial transplantation (SEPSIS + MT, n = 8) samples was extracted and we conducted a comparative transcriptome-wide analysis between three groups. We also confirmed these results with qPCR. In terms of percentage of mitochondrial mapped reads, the SEPSIS + MT group had a significantly higher mapping ratio than the others. RT1-M2 and Cbln2 were identified as highly expressed in SEPSIS + MT compared with SEPSIS. Using SHAM expression levels as another control variable, we further identified six genes (Fxyd4, Apex2l1, Kctd4, 7SK, SNORD94, and SNORA53) that were highly expressed after sepsis induction and observed that their expression levels were attenuated by mitochondrial transplantation. Changes in transcriptomic features were identified after mitochondrial transplantation in sepsis. This might provide a hint for exploring the mechanism of mitochondrial transplantation in sepsis.


Assuntos
Sepse , Transcriptoma , Ratos , Animais , Mitocôndrias/genética , Mitocôndrias/metabolismo , Perfilação da Expressão Gênica , Sepse/genética , Sepse/metabolismo
4.
Int J Mol Sci ; 24(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37373260

RESUMO

Previously, we have shown that mitochondrial transplantation in the sepsis model has immune modulatory effects. The mitochondrial function could have different characteristics dependent on cell types. Here, we investigated whether the effects of mitochondrial transplantation on the sepsis model could be different depending on the cell type, from which mitochondria were isolated. We isolated mitochondria from L6 muscle cells, clone 9 liver cells and mesenchymal stem cells (MSC). We tested the effects of mitochondrial transplantation using in vitro and in vivo sepsis models. We used the LPS stimulation of THP-1 cell, a monocyte cell line, as an in vitro model. First, we observed changes in mitochondrial function in the mitochondria-transplanted cells. Second, we compared the anti-inflammatory effects of mitochondrial transplantation. Third, we investigated the immune-enhancing effects using the endotoxin tolerance model. In the in vivo polymicrobial fecal slurry sepsis model, we examined the survival and biochemical effects of each type of mitochondrial transplantation. In the in vitro LPS model, mitochondrial transplantation with each cell type improved mitochondrial function, as measured by oxygen consumption. Among the three cell types, L6-mitochondrial transplantation significantly enhanced mitochondrial function. Mitochondrial transplantation with each cell type reduced hyper-inflammation in the acute phase of in vitro LPS model. It also enhanced immune function during the late immune suppression phase, as shown by endotoxin tolerance. These functions were not significantly different between the three cell types of origin for mitochondrial transplantation. However, only L6-mitochondrial transplantation significantly improved survival compared to the control in the polymicrobial intraabdominal sepsis model. The effects of mitochondria transplantation on both in vitro and in vivo sepsis models differed depending on the cell types of origin for mitochondria. L6-mitochondrial transplantation might be more beneficial in the sepsis model.


Assuntos
Lipopolissacarídeos , Sepse , Humanos , Lipopolissacarídeos/metabolismo , Mitocôndrias/metabolismo , Sepse/metabolismo , Inflamação/metabolismo , Monócitos/metabolismo
5.
Am J Hum Genet ; 105(6): 1237-1253, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31785787

RESUMO

We report an early-onset autosomal-recessive neurological disease with cerebellar atrophy and lysosomal dysfunction. We identified bi-allelic loss-of-function (LoF) variants in Oxidative Resistance 1 (OXR1) in five individuals from three families; these individuals presented with a history of severe global developmental delay, current intellectual disability, language delay, cerebellar atrophy, and seizures. While OXR1 is known to play a role in oxidative stress resistance, its molecular functions are not well established. OXR1 contains three conserved domains: LysM, GRAM, and TLDc. The gene encodes at least six transcripts, including some that only consist of the C-terminal TLDc domain. We utilized Drosophila to assess the phenotypes associated with loss of mustard (mtd), the fly homolog of OXR1. Strong LoF mutants exhibit late pupal lethality or pupal eclosion defects. Interestingly, although mtd encodes 26 transcripts, severe LoF and null mutations can be rescued by a single short human OXR1 cDNA that only contains the TLDc domain. Similar rescue is observed with the TLDc domain of NCOA7, another human homolog of mtd. Loss of mtd in neurons leads to massive cell loss, early death, and an accumulation of aberrant lysosomal structures, similar to what we observe in fibroblasts of affected individuals. Our data indicate that mtd and OXR1 are required for proper lysosomal function; this is consistent with observations that NCOA7 is required for lysosomal acidification.


Assuntos
Atrofia/patologia , Doenças Cerebelares/patologia , Lisossomos/patologia , Proteínas Mitocondriais/metabolismo , Doenças do Sistema Nervoso/patologia , Estresse Oxidativo , Adolescente , Adulto , Animais , Atrofia/genética , Atrofia/metabolismo , Doenças Cerebelares/genética , Doenças Cerebelares/metabolismo , Criança , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Lisossomos/metabolismo , Masculino , Proteínas Mitocondriais/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Linhagem , Fenótipo , Adulto Jovem
6.
Int J Mol Sci ; 23(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35743025

RESUMO

Immune suppression is known to occur during sepsis. Endotoxin tolerance is considered a mechanism of immune suppression in sepsis. However, the timing and serial changes in endotoxin tolerance have not been fully investigated. In this study, we investigated serial changes in endotoxin tolerance in a polymicrobial sepsis model. Herein, we used a rat model of fecal slurry polymicrobial sepsis. After induction of sepsis, endotoxin tolerance of peripheral blood mononuclear cells (PBMCs) and splenocytes was measured at various time points (6 h, 12 h, 24 h, 48 h, 72 h, 5 days, and 7 days), through the measurement of TNF-α production after stimulation with lipopolysaccharide (LPS) in an ex vivo model. At each time point, we checked for plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 levels. Moreover, we analyzed reactive oxygen species (ROS) as measured by 2',7'-dichlorodihydrofluorescein, plasma lactate, serum alanine aminotransferase (ALT), and creatinine levels. Nuclear factor (NF)-κB, IL-1 receptor-associated kinase (IRAK)-M, and cleaved caspase 3 levels were measured in the spleen. Endotoxin tolerance, measured by TNF-α production stimulated through LPS in PBMCs and splenocytes, was induced early in the sepsis model, starting from 6 h after sepsis. It reached a nadir at 24 to 48 h after sepsis, and then started to recover. Endotoxin tolerance was more prominent in the severe sepsis model. Plasma cytokines peaked at time points ranging from 6 to 12 h after sepsis. ROS levels peaked at 12 h and then decreased. Lactate, ALT, and serum creatinine levels increased up to 24 to 48 h, and then decreased. Phosphorylated p65 and IRAK-M levels of spleen increased up to 12 to 24 h and then decreased. Apoptosis was prominent 48 h after sepsis, and then recovered. In the rat model of polymicrobial sepsis, endotoxin tolerance occurred earlier and started to recover from 24 to 48 h after sepsis.


Assuntos
Lipopolissacarídeos , Sepse , Animais , Tolerância à Endotoxina , Interleucina-6 , Lactatos , Leucócitos Mononucleares , Lipopolissacarídeos/farmacologia , NF-kappa B , Ratos , Espécies Reativas de Oxigênio , Sepse/patologia , Fator de Necrose Tumoral alfa
7.
Korean J Physiol Pharmacol ; 26(3): 195-205, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35477547

RESUMO

Determining blood loss [100% - RBV (%)] is challenging in the management of haemorrhagic shock. We derived an equation estimating RBV (%) via serial haematocrits (Hct1, Hct2) by fixing infused crystalloid fluid volume (N) as [0.015 × body weight (g)]. Then, we validated it in vivo. Mathematically, the following estimation equation was derived: RBV (%) = 24k / [(Hct1 / Hct2) - 1]. For validation, nonongoing haemorrhagic shock was induced in Sprague-Dawley rats by withdrawing 20.0%-60.0% of their total blood volume (TBV) in 5.0% intervals (n = 9). Hct1 was checked after 10 min and normal saline N cc was infused over 10 min. Hct2 was checked five minutes later. We applied a linear equation to explain RBV (%) with 1 / [(Hct1 / Hct2) - 1]. Seven rats losing 30.0%-60.0% of their TBV suffered shock persistently. For them, RBV (%) was updated as 5.67 / [(Hct1 / Hct2) - 1] + 32.8 (95% confidence interval [CI] of the slope: 3.14-8.21, p = 0.002, R2 = 0.87). On a Bland-Altman plot, the difference between the estimated and actual RBV was 0.00 ± 4.03%; the 95% CIs of the limits of agreements were included within the pre-determined criterion of validation (< 20%). For rats suffering from persistent, non-ongoing haemorrhagic shock, we derived and validated a simple equation estimating RBV (%). This enables the calculation of blood loss via information on serial haematocrits under a fixed N. Clinical validation is required before utilisation for emergency care of haemorrhagic shock.

8.
Crit Care ; 25(1): 20, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413559

RESUMO

BACKGROUND: Sepsis has a high mortality rate, but no specific drug has been proven effective, prompting the development of new drugs. Immunologically, sepsis can involve hyperinflammation, immune paralysis, or both, which might pose challenges during drug development. Recently, mitochondrial transplantation has emerged as a treatment modality for various diseases involving mitochondrial dysfunction, but it has never been tested for sepsis. METHODS: We isolated mitochondria from L6 muscle cells and umbilical cord mesenchymal stem cells and tested the quality of the isolated mitochondria. We conducted both in vivo and in vitro sepsis studies. We investigated the effects of intravenous mitochondrial transplantation on cecal slurry model in rats in terms of survival rate, bacterial clearance rate, and the immune response. Furthermore, we observed the effects of mitochondrial transplantation on the immune reaction regarding both hyperinflammation and immune paralysis. To do this, we studied early- and late-phase cytokine production in spleens from cecal slurry model in rats. We also used a lipopolysaccharide (LPS)-stimulated human PBMC monocyte model to confirm the immunological effects of mitochondrial transplantation. Apoptosis and the intrinsic apoptotic pathway were investigated in septic spleens. RESULTS: Mitochondrial transplantation improved survival and bacterial clearance. It also mitigated mitochondrial dysfunction and apoptosis in septic spleens and attenuated both hyperinflammation and immune paralysis in the spleens of cecal slurry model in rats. This effect was confirmed with an LPS-stimulated human PBMC study. CONCLUSIONS: In rat polymicrobial cecal slurry model, the outcome is improved by mitochondrial transplantation, which might have an immunomodulatory effect.


Assuntos
Ceco/fisiopatologia , Mitocôndrias/imunologia , Mitocôndrias/fisiologia , Imunologia de Transplantes/imunologia , Animais , Western Blotting/métodos , Ceco/imunologia , Modelos Animais de Doenças , Ratos , Sepse/fisiopatologia , Sepse/terapia
9.
Int J Mol Sci ; 21(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731602

RESUMO

Stress granules are membraneless organelles composed of numerous components including ribonucleoproteins. The stress granules are characterized by a dynamic complex assembly in response to various environmental stressors, which has been implicated in the coordinated regulation of diverse biological pathways, to exert a protective role against stress-induced cell death. Here, we show that stress granule formation is induced by morusin, a novel phytochemical displaying antitumor capacity through barely known mechanisms. Morusin-mediated induction of stress granules requires activation of protein kinase R (PKR) and subsequent eIF2α phosphorylation. Notably, genetic inactivation of stress granule formation mediated by G3BP1 knockout sensitized cancer cells to morusin treatment. This protective function against morusin-mediated cell death can be attributed at least in part to the sequestration of receptors for activated C kinase-1 (RACK1) within the stress granules, which reduces caspase-3 activation. Collectively, our study provides biochemical evidence for the role of stress granules in suppressing the antitumor capacity of morusin, proposing that morusin treatment, together with pharmacological inhibition of stress granules, could be an efficient strategy for targeting cancer.


Assuntos
Apoptose/efeitos dos fármacos , Grânulos Citoplasmáticos/metabolismo , Flavonoides/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Receptores de Quinase C Ativada/metabolismo , eIF-2 Quinase/metabolismo , Grânulos Citoplasmáticos/patologia , Células HCT116 , Células HeLa , Humanos , Células PC-3
10.
J Nanosci Nanotechnol ; 19(4): 2298-2301, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486986

RESUMO

We optimize various gate head structures to improve breakdown voltage characteristics of AlGaN/GaN high-electron mobility transistors by a two-dimensional device simulator based on a T-shaped gate-connected field-plate. Field-plates (FPs) alleviate electric field spikes near the gate and drain-side overlapping edges, which eventually disperse electron avalanche and charge trapping effects. Hence, the more uniform electric field distribution provides improved breakdown voltage of the device. Multiple configurations, such as extension of the FP towards the source or drain, and symmetric extension, were investigated and compared. The best results were acquired when the FP was extended towards the drain, with an optimum length of 2 µm, which produced maximum breakdown voltage of 224 V and maximum transconductance of 132.5 mS/mm. Also, the optimum Si3N4 passivation layer thickness based on a T-shaped gate-connected FP structure was 50 nm.

11.
J Nanosci Nanotechnol ; 18(3): 2041-2044, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448708

RESUMO

In this study, we present the microwave-assisted growth (MAG) of ZnO nanorods (ZNRs) using a preheating hydrothermal method under tailored preheating and postheating growth conditions. The perimeters such as solution concentration, preheating time, and postheating time, were changed to optimize ZNR growth and the growth was carried out in a domestic 850 watt microwave oven. Preheated solution was utilized as an accelerator to increase the aspect ratio of the ZNRs and reduce the fabrication time. Because of a long fabrication time and limited length in the conventional MAG method, preheating condition was used for efficient growth of nanorods through homogeneous nucleation in the solution and then heterogeneous nucleation of the formed ZNRs on seeded substrate during postheating process. The nanostructures were characterized with scanning electron microscopy to look at the morphology and dimensions. Dimensions of ZNRs kept on increasing as the molar concentration went higher. Preheating time highly affected the morphology, dimensions, and aspect ratio of ZNRs and postheating time not only ensured the stability of ZNRs with substrate due to heterogeneous nucleation process but also influenced the morphology of ZNRs.

12.
PLoS One ; 19(2): e0297846, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38412189

RESUMO

Johnston's organ, the Drosophila auditory organ, is anatomically very different from the mammalian organ of Corti. However, recent evidence indicates significant cellular and molecular similarities exist between vertebrate and invertebrate hearing, suggesting that Drosophila may be a useful platform to determine the function of the many mammalian deafness genes whose underlying biological mechanisms are poorly characterized. Our goal was a comprehensive screen of all known orthologues of mammalian deafness genes in the fruit fly to better understand conservation of hearing mechanisms between the insect and the fly and ultimately gain insight into human hereditary deafness. We used bioinformatic comparisons to screen previously reported human and mouse deafness genes and found that 156 of them have orthologues in Drosophila melanogaster. We used fluorescent imaging of T2A-GAL4 gene trap and GFP or YFP fluorescent protein trap lines for 54 of the Drosophila genes and found 38 to be expressed in different cell types in Johnston's organ. We phenotypically characterized the function of strong loss-of-function mutants in three genes expressed in Johnston's organ (Cad99C, Msp-300, and Koi) using a courtship assay and electrophysiological recordings of sound-evoked potentials. Cad99C and Koi were found to have significant courtship defects. However, when we tested these genes for electrophysiological defects in hearing response, we did not see a significant difference suggesting the courtship defects were not caused by hearing deficiencies. Furthermore, we used a UAS/RNAi approach to test the function of seven genes and found two additional genes, CG5921 and Myo10a, that gave a statistically significant delay in courtship but not in sound-evoked potentials. Our results suggest that many mammalian deafness genes have Drosophila homologues expressed in the Johnston's organ, but that their requirement for hearing may not necessarily be the same as in mammals.


Assuntos
Surdez , Drosophila , Animais , Humanos , Camundongos , Drosophila/genética , Drosophila melanogaster/genética , Audição/genética , Vertebrados , Mamíferos
13.
J Pers Med ; 14(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38929866

RESUMO

Hyperinflammation occurs in sepsis, especially in the early phase, and it could have both positive and negative effects on sepsis. Previously, we showed that a new concept of NF-κB inhibitor, exosome-based super-repressor IκBα (Exo-srIκB) delivery, has a beneficial effect on sepsis. Here, we further investigate the therapeutic effects of Exo-srIκB at different severities and phases of sepsis using an animal polymicrobial intra-abdominal infection model. We used a rat model of fecal slurry polymicrobial sepsis. First, we determined the survival effects of Exo-srIκB on sepsis according to the severity. We used two different severities of the animal sepsis model. The severe model had a mortality rate of over 50%. The mild/moderate model had a less than 30% mortality rate. Second, we administered the Exo-srIκB at various time points (1 h, 6 h, and 24 h after fecal slurry administration) to determine the therapeutic effect of Exo-srIκB at different phases of sepsis. Lastly, we determined the effects of the Exo-srIκB on cytokine production, arterial blood gas, electrolyte, and lactate. The survival gain was statistically significant in the severe sepsis model when Exo-srIκB was administered 6 h after sepsis. Interleukin 6 and interleukin-10 were significantly decreased in the kidney when administered with Exo-srIκB. The laboratory data showed that lactate, glucose, and potassium levels were significantly lowered in the NF-κB inhibitor group. In conclusion, Exo-srIκB exhibited a beneficial therapeutic effect when administered 6 h post fecal slurry administration in a severe sepsis model.

14.
Nat Commun ; 15(1): 3326, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637532

RESUMO

Cdk8 in Drosophila is the orthologue of vertebrate CDK8 and CDK19. These proteins have been shown to modulate transcriptional control by RNA polymerase II. We found that neuronal loss of Cdk8 severely reduces fly lifespan and causes bang sensitivity. Remarkably, these defects can be rescued by expression of human CDK19, found in the cytoplasm of neurons, suggesting a non-nuclear function of CDK19/Cdk8. Here we show that Cdk8 plays a critical role in the cytoplasm, with its loss causing elongated mitochondria in both muscles and neurons. We find that endogenous GFP-tagged Cdk8 can be found in both the cytoplasm and nucleus. We show that Cdk8 promotes the phosphorylation of Drp1 at S616, a protein required for mitochondrial fission. Interestingly, Pink1, a mitochondrial kinase implicated in Parkinson's disease, also phosphorylates Drp1 at the same residue. Indeed, overexpression of Cdk8 significantly suppresses the phenotypes observed in flies with low levels of Pink1, including elevated levels of ROS, mitochondrial dysmorphology, and behavioral defects. In summary, we propose that Pink1 and Cdk8 perform similar functions to promote Drp1-mediated fission.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Humanos , Fosforilação , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Dinâmica Mitocondrial/genética , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Quinase 8 Dependente de Ciclina/genética , Quinase 8 Dependente de Ciclina/metabolismo
15.
bioRxiv ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38559164

RESUMO

Peripheral tissues become disrupted in Alzheimer's Disease (AD). However, a comprehensive understanding of how the expression of AD-associated toxic proteins, Aß42 and Tau, in neurons impacts the periphery is lacking. Using Drosophila, a prime model organism for studying aging and neurodegeneration, we generated the Alzheimer's Disease Fly Cell Atlas (AD-FCA): whole-organism single-nucleus transcriptomes of 219 cell types from adult flies neuronally expressing human Aß42 or Tau. In-depth analyses and functional data reveal impacts on peripheral sensory neurons by Aß42 and on various non-neuronal peripheral tissues by Tau, including the gut, fat body, and reproductive system. This novel AD atlas provides valuable insights into potential biomarkers and the intricate interplay between the nervous system and peripheral tissues in response to AD-associated proteins.

16.
Adv Sci (Weinh) ; 10(12): e2206355, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36814343

RESUMO

In searching for unique and unexplored 2D materials, the authors try to investigate for the very first time the use of delaminated V-MXene coupled with precious metal ruthenium (Ru) through atomic layer deposition (ALD) for various contact and noncontact mode of real-time temperature sensing applications at the human-machine interface. The novel delaminated V-MXene (DM-V2 CTx ) engineered ruthenium-ALD (Ru-ALD) temperature sensor demonstrates a competitive sensing performance of 1.11% °C-1 as of only V-MXene of 0.42% °C-1 . A nearly threefold increase in sensing and reversibility performance linked to the highly ordered few-layered V-MXene and selective, well-controlled Ru atomic doping by ALD for the successful formation of Ru@DM-V2 CTX heterostructure. The advanced heterostructure formation, the mechanism, and the role of Ru have been comprehensively investigated by ultra-high-resolution transmission/scanning transmission electron microscopies coupled with next-generation spherical aberration correction technology and fast, accurate elemental mapping quantifications, also by ultraviolet photoelectron spectroscopy. To the knowledge, this work is the first to use the novel, optimally processed V-MXene over conventionally used Ti-MXene and its surface-internal structure engineering by Ru-ALD process-based temperature-sensing devices function and operational demonstrations. The current work could potentially motivate the development of multifunctional, future, next-generation, safe, personal healthcare electronic devices by the industrially scalable ALD technique.


Assuntos
Rutênio , Humanos , Eletrônica , Engenharia , Sensação Térmica
17.
J Neural Eng ; 20(4)2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37459853

RESUMO

Objective. Brain-computer interfaces can restore various forms of communication in paralyzed patients who have lost their ability to articulate intelligible speech. This study aimed to demonstrate the feasibility of closed-loop synthesis of artificial speech sounds from human cortical surface recordings during silent speech production.Approach. Ten participants with intractable epilepsy were temporarily implanted with intracranial electrode arrays over cortical surfaces. A decoding model that predicted audible outputs directly from patient-specific neural feature inputs was trained during overt word reading and immediately tested with overt, mimed and imagined word reading. Predicted outputs were later assessed objectively against corresponding voice recordings and subjectively through human perceptual judgments.Main results. Artificial speech sounds were successfully synthesized during overt and mimed utterances by two participants with some coverage of the precentral gyrus. About a third of these sounds were correctly identified by naïve listeners in two-alternative forced-choice tasks. A similar outcome could not be achieved during imagined utterances by any of the participants. However, neural feature contribution analyses suggested the presence of exploitable activation patterns during imagined speech in the postcentral gyrus and the superior temporal gyrus. In future work, a more comprehensive coverage of cortical surfaces, including posterior parts of the middle frontal gyrus and the inferior frontal gyrus, could improve synthesis performance during imagined speech.Significance.As the field of speech neuroprostheses is rapidly moving toward clinical trials, this study addressed important considerations about task instructions and brain coverage when conducting research on silent speech with non-target participants.


Assuntos
Fonética , Fala , Humanos , Fala/fisiologia , Encéfalo , Lobo Frontal , Córtex Pré-Frontal , Mapeamento Encefálico/métodos
18.
Cell Metab ; 35(5): 855-874.e5, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37084732

RESUMO

VLCFAs (very-long-chain fatty acids) are the most abundant fatty acids in myelin. Hence, during demyelination or aging, glia are exposed to higher levels of VLCFA than normal. We report that glia convert these VLCFA into sphingosine-1-phosphate (S1P) via a glial-specific S1P pathway. Excess S1P causes neuroinflammation, NF-κB activation, and macrophage infiltration into the CNS. Suppressing the function of S1P in fly glia or neurons, or administration of Fingolimod, an S1P receptor antagonist, strongly attenuates the phenotypes caused by excess VLCFAs. In contrast, elevating the VLCFA levels in glia and immune cells exacerbates these phenotypes. Elevated VLCFA and S1P are also toxic in vertebrates based on a mouse model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). Indeed, reducing VLCFA with bezafibrate ameliorates the phenotypes. Moreover, simultaneous use of bezafibrate and fingolimod synergizes to improve EAE, suggesting that lowering VLCFA and S1P is a treatment avenue for MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Animais , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Imunossupressores/farmacologia , Doenças Neuroinflamatórias , Bezafibrato , Propilenoglicóis/farmacologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/metabolismo , Neuroglia/metabolismo , Ácidos Graxos
19.
Science ; 380(6650): eadg0934, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37319212

RESUMO

Aging is characterized by a decline in tissue function, but the underlying changes at cellular resolution across the organism remain unclear. Here, we present the Aging Fly Cell Atlas, a single-nucleus transcriptomic map of the whole aging Drosophila. We characterized 163 distinct cell types and performed an in-depth analysis of changes in tissue cell composition, gene expression, and cell identities. We further developed aging clock models to predict fly age and show that ribosomal gene expression is a conserved predictive factor for age. Combining all aging features, we find distinctive cell type-specific aging patterns. This atlas provides a valuable resource for studying fundamental principles of aging in complex organisms.


Assuntos
Envelhecimento , Senescência Celular , Drosophila melanogaster , Animais , Envelhecimento/genética , Perfilação da Expressão Gênica , Transcriptoma , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Atlas como Assunto
20.
Materials (Basel) ; 15(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35160654

RESUMO

Gallium-based liquid metal (GaLM) alloys have been extensively used in applications ranging from electronics to drug delivery systems. To broaden the understanding and applications of GaLMs, this paper discusses the interfacial behavior of eutectic gallium-indium liquid metal (EGaIn) droplets in various solvents. No significant difference in contact angles of EGaIn is observed regardless of the solvent types. However, the presence or absence of a conical tip on EGaIn droplets after dispensing could indirectly support that the interfacial energy of EGaIn is relatively low in non-polar solvents. Furthermore, in the impact experiments, the EGaIn droplet bounces off in the polar solvents of water and dimethyl sulfoxide (DMSO), whereas it spreads and adheres to the substrate in the non-polar solvents of hexane and benzene. Based on the dimensionless We number, it can be stated that the different impact behavior depending on the solvent types is closely related to the interfacial energy of EGaIn in each solvent. Finally, the contact angles and shapes of EGaIn droplets in aqueous buffer solutions with different pH values (4, 7, and 10) are compared. In the pH 10 buffer solution, the EGaIn droplet forms a spherical shape without the conical tip, representing the high surface energy. This is associated with the dissolution of the "interfacial energy-reducing" surface layer on EGaIn, which is supported by the enhanced concentration of gallium ion released from EGaIn in the buffer solution.

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