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1.
Nature ; 619(7969): 394-402, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37344600

RESUMO

In eukaryotes, small RNA guides, such as small interfering RNAs and microRNAs, direct AGO-clade Argonaute proteins to regulate gene expression and defend the genome against external threats. Only animals make a second clade of Argonaute proteins: PIWI proteins. PIWI proteins use PIWI-interacting RNAs (piRNAs) to repress complementary transposon transcripts1,2. In theory, transposons could evade silencing through target site mutations that reduce piRNA complementarity. Here we report that, unlike AGO proteins, PIWI proteins efficiently cleave transcripts that are only partially paired to their piRNA guides. Examination of target binding and cleavage by mouse and sponge PIWI proteins revealed that PIWI slicing tolerates mismatches to any target nucleotide, including those flanking the scissile phosphate. Even canonical seed pairing is dispensable for PIWI binding or cleavage, unlike plant and animal AGOs, which require uninterrupted target pairing from the seed to the nucleotides past the scissile bond3,4. PIWI proteins are therefore better equipped than AGO proteins to target newly acquired or rapidly diverging endogenous transposons without recourse to new small RNA guides. Conversely, the minimum requirements for PIWI slicing are sufficient to avoid inadvertent silencing of host RNAs. Our results demonstrate the biological advantage of PIWI over AGO proteins in defending the genome against transposons and suggest an explanation for why the piRNA pathway was retained in animal evolution.


Assuntos
Proteínas Argonautas , Elementos de DNA Transponíveis , Inativação Gênica , RNA de Interação com Piwi , Animais , Camundongos , Proteínas Argonautas/classificação , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Elementos de DNA Transponíveis/genética , RNA de Interação com Piwi/genética , RNA de Interação com Piwi/metabolismo , Evolução Molecular , Fosfatos/metabolismo , Especificidade por Substrato
2.
Mol Cell ; 81(2): 223-225, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33482091

RESUMO

Han et al. (2020) and Shi et al. (2020) report that the E3 ubiquitin ligase ZSWIM8 senses when an RNA and an Argonaute protein-bound microRNA are extensively base paired and directs Argonaute destruction by the proteasome. The result is degradation of the microRNA.


Assuntos
MicroRNAs , Ubiquitina , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , MicroRNAs/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
4.
Reproduction ; 165(3): R91-R102, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538648

RESUMO

In brief: Mouse PIWI-interacting RNAs (piRNAs) are indispensable for spermatogenesis, but whether these small RNAs serve any function beyond gametogenesis is rarely explored. This review summarizes recent findings that demonstrated a requirement for piRNAs in sperm maturation and discusses a potential intergenerational role for paternal piRNAs. Abstract: Unique to animals, PIWI-interacting RNAs (piRNAs) defend organisms against threats to germline integrity evoked by transposons, retroviruses, and inappropriate expression of protein-coding genes. Characterization of mouse piRNAs and studies of more than a dozen piRNA pathway protein mutants detailed in the past 15 years have firmly established an essential role for piRNAs in male fertility. Despite their vital function in spermatogenesis, mammalian piRNAs were thought to be dispensable beyond gamete formation because all piRNA pathway protein mouse mutants are invariably sterile and do not produce sperm. In contrast to the specialized purpose of piRNAs in gamete formation, tRNA-derived fragments and microRNAs have been the focus of research in RNA-mediated paternal contribution, providing additional examples of the versatility of non-coding RNAs. In recent years, the direct elimination of mouse piRNAs using CRISPR/Cas revealed their extended function in post-testicular sperm maturation. An intergenerational contribution from paternal piRNAs has also been proposed. Together with insights into piRNAs in oocytes and early embryos in mice and other mammals, these newly proposed functions of mammalian piRNAs invite further investigations of piRNA dynamics during sperm maturation and fertilization as well as their roles in reproduction beyond gametogenesis.


Assuntos
RNA de Interação com Piwi , Sêmen , Masculino , Animais , Camundongos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Espermatogênese/genética , Mamíferos/genética
5.
Proc Natl Acad Sci U S A ; 117(49): 31267-31277, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229585

RESUMO

Mushroom-forming fungi in the order Agaricales represent an independent origin of bioluminescence in the tree of life; yet the diversity, evolutionary history, and timing of the origin of fungal luciferases remain elusive. We sequenced the genomes and transcriptomes of five bonnet mushroom species (Mycena spp.), a diverse lineage comprising the majority of bioluminescent fungi. Two species with haploid genome assemblies ∼150 Mb are among the largest in Agaricales, and we found that a variety of repeats between Mycena species were differentially mediated by DNA methylation. We show that bioluminescence evolved in the last common ancestor of mycenoid and the marasmioid clade of Agaricales and was maintained through at least 160 million years of evolution. Analyses of synteny across genomes of bioluminescent species resolved how the luciferase cluster was derived by duplication and translocation, frequently rearranged and lost in most Mycena species, but conserved in the Armillaria lineage. Luciferase cluster members were coexpressed across developmental stages, with the highest expression in fruiting body caps and stipes, suggesting fruiting-related adaptive functions. Our results contribute to understanding a de novo origin of bioluminescence and the corresponding gene cluster in a diverse group of enigmatic fungal species.


Assuntos
Agaricales/genética , Evolução Molecular , Carpóforos/genética , Luminescência , Agaricales/química , Sequência de Bases , Carpóforos/química , Genoma Fúngico/genética , Luciferases/genética , Filogenia
6.
Clin Otolaryngol ; 47(1): 107-114, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34547825

RESUMO

OBJECTIVE: To evaluate the correlation of neonatal parameters with late-onset sensorineural hearing loss (SNHL) and vestibular dysfunction in individuals with congenital cytomegalovirus (cCMV) infection using the National Health Insurance Research Database (NHIRD) in Taiwan. DESIGN: Retrospective cohort study. SETTING: The whole Taiwanese population. PARTICIPANTS: Patients with related diagnostic codes and examinations in their records were regarded as having cCMV infection. Each subject in that group was matched to 10 control individuals with noncongenital CMV infection on the basis of several neonatal parameters, including low gestational age, low birth weight, low Apgar score, maternal history of CMV infection and prolonged cCMV infection. A total of 5893 and 58 930 participants were enrolled in the study and control groups, respectively. MAIN OUTCOME MEASURES: The main outcomes were the development of SNHL and the development of vestibular dysfunction within one year after birth as reflected by diagnostic codes and specific examinations. Cox proportional hazard regression was used to calculate the adjusted hazard ratio (HR) and 95% confidence interval (CI) of each primary outcome between the two groups. RESULTS: Overall, 109 and 397 episodes of SNHL developed in the study group and the control group, respectively, and the study group demonstrated a significantly higher incidence of SNHL (adjusted HR: 2.56; 95% CI: 2.07-3.18). In addition, similar incidence rates of vestibular dysfunction were found in the study group and the control group, with 7 and 90 events, respectively (adjusted HR: 0.77; 95% CI: 0.36-1.67). In subgroup analyses, a higher incidence of SNHL was correlated with lower gestational age (GA) (adjusted HR: 2.09; 95% CI: 1.29-3.39), lower birth weight (BW) (adjusted HR: 2.05; 95% CI: 1.28-3.30) and prolonged cCMV infection (adjusted HR: 3.92; 95% CI: 1.95-7.88). CONCLUSIONS: Low GA, low BW and a long disease course are significantly correlated with late-onset SNHL in cCMV infection.


Assuntos
Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/complicações , Perda Auditiva Neurossensorial/virologia , Doenças Vestibulares/virologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Estudos Retrospectivos , Fatores de Risco
7.
Mol Cell ; 52(1): 113-23, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24055343

RESUMO

Because microRNAs (miRNAs) influence the expression of many genes in cells, discovering how the miRNA pathway is regulated is an important area of investigation. We found that the Drosophila miRNA-induced silencing complex (miRISC) exists in multiple forms. A constitutive form, called G-miRISC, is comprised of Ago1, miRNA, and GW182. Two distinct miRISC complexes that lack GW182 are regulated by mitogenic signaling. Exposure of cells to serum, lipids, or the tumor promoter PMA suppressed formation of these complexes. P-miRISC is comprised of Ago1, miRNA, and Loqs-PB, and it associates with mRNAs assembled into polysomes. The other regulated Ago1 complex associates with membranous organelles and is likely an intermediate in miRISC recycling. The formation of these complexes is correlated with a 5- to 10-fold stronger repression of target gene expression inside cells. Taken together, these results indicate that mitogenic signaling regulates the miRNA effector machinery to attenuate its repressive activities.


Assuntos
MicroRNAs/metabolismo , Complexo de Inativação Induzido por RNA/metabolismo , Transdução de Sinais , Animais , Proteínas Argonautas/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Regulação da Expressão Gênica , Inativação Gênica , Insulina/metabolismo , Metabolismo dos Lipídeos , MicroRNAs/genética , Mitógenos/farmacologia , Polirribossomos/metabolismo , Interferência de RNA , Proteínas de Ligação a RNA/metabolismo , Complexo de Inativação Induzido por RNA/genética , Soro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Transfecção
8.
BMC Genomics ; 19(1): 531, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30001700

RESUMO

BACKGROUND: RNA-seq and small RNA-seq are powerful, quantitative tools to study gene regulation and function. Common high-throughput sequencing methods rely on polymerase chain reaction (PCR) to expand the starting material, but not every molecule amplifies equally, causing some to be overrepresented. Unique molecular identifiers (UMIs) can be used to distinguish undesirable PCR duplicates derived from a single molecule and identical but biologically meaningful reads from different molecules. RESULTS: We have incorporated UMIs into RNA-seq and small RNA-seq protocols and developed tools to analyze the resulting data. Our UMIs contain stretches of random nucleotides whose lengths sufficiently capture diverse molecule species in both RNA-seq and small RNA-seq libraries generated from mouse testis. Our approach yields high-quality data while allowing unique tagging of all molecules in high-depth libraries. CONCLUSIONS: Using simulated and real datasets, we demonstrate that our methods increase the reproducibility of RNA-seq and small RNA-seq data. Notably, we find that the amount of starting material and sequencing depth, but not the number of PCR cycles, determine PCR duplicate frequency. Finally, we show that computational removal of PCR duplicates based only on their mapping coordinates introduces substantial bias into data analysis.


Assuntos
RNA/isolamento & purificação , Análise de Sequência de RNA/métodos , Animais , Biblioteca Gênica , Masculino , Camundongos , Reação em Cadeia da Polimerase , RNA/química , RNA/metabolismo , Reprodutibilidade dos Testes , Testículo/metabolismo
9.
Neuroendocrinology ; 107(2): 147-157, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29920496

RESUMO

BACKGROUND: The notion that exposure to chronic stress predisposes individuals to developing type 2 diabetes (T2D) has gained much attention in recent decades. Long-term stress induces neuroadaptation in the amygdala and increases corticosterone levels. Corticosterone, the major stress hormone in rodents, induces insulin resistance and obesity in mice. However, little is known about whether the stress-induced amygdalar neuroadaptation could promote the risk of T2D. METHODS: We used an 11-week high-fat diet (HFD) feeding paradigm to induce insulin dysfunction in mice, followed by implementation of a 10-day social defeat (SD) stress protocol. RESULTS: Mice receiving SD at the beginning of the HFD feeding aggravated HFD-induced insulin resistance and white adipose tissue expansion. HFD mice had higher levels of plasma corticosterone, which was not affected by the SD. The SD stress upregulated the expression of TrkB and synaptotagmin-4 in the amygdala of HFD mice. Bilateral lesions of the central amygdalae before SD stress inhibited the stress-induced aggravating effect without affecting the HFD-induced elevation of plasma corticosterone. CONCLUSIONS: Stress aggravates HFD-induced insulin resistance and neuroadaptation in the amygdala. The HFD-induced insulin resistance is amygdala-dependent. Understanding the role of stress-induced amygdalar adaptation in the development of T2D could inform therapies aimed at reducing chronic stressors to decrease the risk for T2D.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Resistência à Insulina/fisiologia , Plasticidade Neuronal/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
PeerJ ; 12: e16908, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344294

RESUMO

Despite reporting very few mpox cases in early 2023, mainland China observed a surge of over 500 cases during the summer. Amid ambiguous prevention strategies and stigma surrounding mpox transmission, the epidemic silently escalated. This study aims to quantify the scale of the mpox epidemic and assess the transmission dynamics of the virus by estimating the effective reproduction number (Re) during its early phase. Publicly available data were aggregated to obtain daily mpox case counts in mainland China, and the Re value was estimated using an exponential growth model. The mean Re value was found to be 1.57 (95% credible interval [1.38-1.78]), suggesting a case doubling time of approximately 2 weeks. This estimate was compared with Re values from 16 other countries' national outbreaks in 2022 that had cumulative case count exceeding 700 symptomatic cases by the end of that year. The Re estimates for these outbreaks ranged from 1.13 for Portugal to 2.31 for Colombia. The pooled mean Re was 1.49 (95% credible interval [1.32-1.67]), which aligns closely with the Re for mainland China. These findings underscore the need for immediate and effective control measures including targeted vaccination campaigns to mitigate the further spread and impact of the epidemic.


Assuntos
COVID-19 , Epidemias , Mpox , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , China/epidemiologia
11.
Curr Biol ; 34(12): 2739-2747.e3, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38815578

RESUMO

Somatosensation is essential for animals to perceive the external world through touch, allowing them to detect physical contact, temperature, pain, and body position. Studies on rodent vibrissae have highlighted the organization and processing in mammalian somatosensory pathways.1,2 Comparative research across vertebrates is vital for understanding evolutionary influences and ecological specialization on somatosensory systems. Birds, with their diverse morphologies, sensory abilities, and behaviors, serve as ideal models for investigating the evolution of somatosensation. Prior studies have uncovered tactile-responsive areas within the avian telencephalon, particularly in pigeons,3,4,5,6 parrots,7 and finches,8 but variations in somatosensory maps and responses across avian species are not fully understood. This study aims to explore somatotopic organization and neural coding in the telencephalon of Anna's hummingbirds (Calypte anna) and zebra finches (Taeniopygia guttata) by using in vivo extracellular electrophysiology to record activity in response to controlled tactile stimuli on various body regions. These findings reveal unique representations of body regions across distinct forebrain somatosensory nuclei, indicating significant differences in the extent of areas dedicated to certain body surfaces, which may correlate with their behavioral importance.


Assuntos
Tentilhões , Prosencéfalo , Animais , Tentilhões/fisiologia , Prosencéfalo/fisiologia , Tato/fisiologia , Aves/fisiologia , Masculino , Percepção do Tato/fisiologia , Feminino
12.
J Comp Neurol ; 532(2): e25556, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37938923

RESUMO

Birds have a comprehensive network of sensorimotor projections extending from the forebrain and midbrain to the cerebellum via the pontine nuclei, but the organization of these circuits in the pons is not thoroughly described. Inputs to the pontine nuclei include two retinorecipient areas, nucleus lentiformis mesencephali (LM) and nucleus of the basal optic root (nBOR), which are important structures for analyzing optic flow. Other crucial regions for visuomotor control include the retinorecipient ventral lateral geniculate nucleus (GLv), and optic tectum (TeO). These visual areas, together with the somatosensory area of the anterior (rostral) Wulst, which is homologous to the primary somatosensory cortex in mammals, project to the medial and lateral pontine nuclei (PM, PL). In this study, we used injections of fluorescent tracers to study the organization of these visual and somatosensory inputs to the pontine nuclei in zebra finches. We found a topographic organization of inputs to PM and PL. The PM has a lateral subdivision that predominantly receives projections from the ipsilateral anterior Wulst. The medial PM receives bands of inputs from the ipsilateral GLv and the nucleus laminaris precommisulis, located medial to LM. We also found that the lateral PL receives a strong ipsilateral projection from TeO, while the medial PL and region between the PM and PL receive less prominent projections from nBOR, bilaterally. We discuss these results in the context of the organization of pontine inputs to the cerebellum and possible functional implications of diverse somato-motor and visuomotor inputs and parcellation in the pontine nuclei.


Assuntos
Tentilhões , Vias Visuais , Animais , Colículos Superiores , Ponte , Cerebelo , Mamíferos
13.
Optom Vis Sci ; 90(10): 1048-56, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23912969

RESUMO

PURPOSE: Dry eye is the most common complication after LASIK procedure and is associated with corneal denervation. We conducted the study to compare dry eye parameters and corneal sensitivity (CS) after laser in situ keratomileusis (LASIK) with a femtosecond laser (FS) or microkeratome (MK). METHODS: In this prospective, nonrandomized, comparative study, 87 consecutive patients with myopia were assigned to receive either LASIK surgery with an FS (n = 44) or MK-assisted LASIK surgery (n = 43). The groups were age and sex matched. Corneal sensitivity, Schirmer testing, tear breakup time (TBUT), conjunctival and corneal stainings, and a subjective questionnaire (Ocular Surface Disease Index [OSDI]) were evaluated preoperatively, at 1 week, and at 1, 3, and 6 months postoperatively. RESULTS: Preoperative spherical equivalent and sphere, calculated ablation depth, and suction time differed significantly between the two groups (p < 0.01, all comparisons). Postoperatively, CS decreased in both groups and gradually recovered. Schirmer test values were not significantly different throughout the postoperative time points between the groups. Laser in situ keratomileusis-induced corneal epitheliopathy was also increased after operation in both groups. However, there was no significant difference between the groups in corneal and conjunctival staining scores. The OSDI scores were increased postoperatively in both groups. After adjustment for the calculated ablation depth, TBUT was the only parameter that was statistically higher in the FS group than in the MK group (p = 0.03). CONCLUSIONS: Both FS- and MK-assisted LASIK reduced CS and TBUT and increased corneal staining and OSDI scores. However, TBUT was significantly higher in the FS group than in the MK group after operation.


Assuntos
Córnea/fisiopatologia , Síndromes do Olho Seco/etiologia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Complicações Pós-Operatórias , Adulto , Síndromes do Olho Seco/fisiopatologia , Feminino , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/instrumentação , Masculino , Miopia/complicações , Miopia/fisiopatologia , Estudos Prospectivos , Sensação/fisiologia , Retalhos Cirúrgicos , Inquéritos e Questionários , Lágrimas/química
14.
J Agric Food Chem ; 71(1): 382-397, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36562602

RESUMO

Hyperuricemic nephropathy (HN) is caused by urate crystals that get deposited in the kidney and contribute to renal fibrosis. Uric acid (UA) has been proven to directly cause renal mesangial cell oxidative stress and fibrosis in the pathogenesis of HN. Some antioxidants can be used as chemopreventive agents of HN. Hibiscus sabdariffa leaf extracts (HLE), rich in polyphenol, have been shown to possess hypoglycemic, antioxidant, hypolipidemic, antiatherosclerotic, and anticancer effects. The aim of the study is to examine the inhibitory effect of HLE and its main component ellagic acid (EA) on renal fibrosis. In vitro, mouse renal glomerular mesangial SV40MES13 cells pretreated with UA were demonstrated to trigger obvious morphological changes and viability loss, as well as affect matrix metalloproteinases (MMPs) activities. Noncytotoxic doses of HLE and EA abolished the UA-induced cell injury and MMP-2/9 secretion. In addition, HLE and EA exhibited antioxidant and anti-inflammatory effects on the UA-treated cells with a reduction in transforming growth factor-beta (TGF-ß) production. Next, the UA-activated pro-fibrotic factors, extracellular matrix (ECM) deposition, and epithelial-mesenchymal-transition (EMT) were inhibited by HLE or EA. Mechanistic assays indicated that antifibrotic effects of HLE might be mediated via TGF-ß/Smad signaling, as confirmed by the transfection of Smad7 siRNA. In vivo, HLE and EA supplementations significantly alleviated HN development, which may result from inhibiting adenine-induced TGF-ß production accompanying oxidative stress and inflammation, as well as fibrogenesis. Our data imply that EA-enriched HLE regulates the TGF-ß/Smad signaling, which in turn led to reduced renal mesangial cell injury and fibrosis in HN and provided a new mechanism for its nephroprotective activity.


Assuntos
Hibiscus , Hiperuricemia , Nefropatias , Animais , Camundongos , Antioxidantes/uso terapêutico , Ácido Elágico/farmacologia , Fibrose , Hibiscus/química , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Nefropatias/tratamento farmacológico , Nefropatias/genética , Nefropatias/prevenção & controle , Fator de Crescimento Transformador beta , Ácido Úrico , Folhas de Planta/química
15.
J Comp Neurol ; 531(6): 640-662, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36648211

RESUMO

In birds, the nucleus of the basal optic root (nBOR) and the nucleus lentiformis mesencephali (LM) are brainstem nuclei involved in the analysis of optic flow. A major projection site of both nBOR and LM is the medial column of the inferior olive (IO), which provides climbing fibers to the vestibulocerebellum. This pathway has been well documented in pigeons, but not other birds. Recent works have highlighted that zebra finches show specializations with respect to optic flow processing, which may be reflected in the organization of optic flow pathways to the IO. In this study, we characterized the organization of these pathways in zebra finches. We found that the medial column consists of at least eight subnuclei (i-viii) visible in Nissl-stained tissue. Using anterograde traces we found that the projections from LM and nBOR to the IO were bilateral, but heavier to the ipsilateral side, and showed a complementary pattern: LM projected to subnucleus i, whereas nBOR projected to subnuclei ii and v. Using retrograde tracers, we found that these subnuclei (i, ii and v) projected to the vestibulocerebellum (folia IXcd and X), whereas the other subnuclei projected to IXab and the lateral margin of VII and VIII. The nBOR also projected ipsilaterally to the caudo-medial dorsal lamella of the IO, which the retrograde experiments showed as projecting to the medial margin of VII and VIII. We compare these results with previous studies in other avian species.


Assuntos
Tentilhões , Fluxo Óptico , Animais , Vias Visuais , Columbidae , Cerebelo , Núcleo Olivar
16.
Front Psychol ; 13: 864416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693500

RESUMO

Visual programming language is a crucial part of learning programming. On this basis, it is essential to use visual programming to lower the learning threshold for students to learn about artificial intelligence (AI) to meet current demands in higher education. Therefore, a 3-h AI course with an RGB-to-HSL learning task was implemented; the results of which were used to analyze university students from two different disciplines. Valid data were collected for 65 students (55 men, 10 women) in the Science (Sci)-student group and 39 students (20 men, 19 women) in the Humanities (Hum)-student group. Independent sample t-tests were conducted to analyze the difference between cognitive styles and computational thinking. No significant differences in either cognitive style or computational thinking ability were found after the AI course, indicating that taking visual AI courses lowers the learning threshold for students and makes it possible for them to take more difficult AI courses, which in turn effectively helping them acquire AI knowledge, which is crucial for cultivating talent in the field of AI.

17.
Elife ; 112022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36476387

RESUMO

Axon degeneration contributes to the disruption of neuronal circuit function in diseased and injured nervous systems. Severed axons degenerate following the activation of an evolutionarily conserved signaling pathway, which culminates in the activation of SARM1 in mammals to execute the pathological depletion of the metabolite NAD+. SARM1 NADase activity is activated by the NAD+ precursor nicotinamide mononucleotide (NMN). In mammals, keeping NMN levels low potently preserves axons after injury. However, it remains unclear whether NMN is also a key mediator of axon degeneration and dSarm activation in flies. Here, we demonstrate that lowering NMN levels in Drosophila through the expression of a newly generated prokaryotic NMN-Deamidase (NMN-D) preserves severed axons for months and keeps them circuit-integrated for weeks. NMN-D alters the NAD+ metabolic flux by lowering NMN, while NAD+ remains unchanged in vivo. Increased NMN synthesis by the expression of mouse nicotinamide phosphoribosyltransferase (mNAMPT) leads to faster axon degeneration after injury. We also show that NMN-induced activation of dSarm mediates axon degeneration in vivo. Finally, NMN-D delays neurodegeneration caused by loss of the sole NMN-consuming and NAD+-synthesizing enzyme dNmnat. Our results reveal a critical role for NMN in neurodegeneration in the fly, which extends beyond axonal injury. The potent neuroprotection by reducing NMN levels is similar to the interference with other essential mediators of axon degeneration in Drosophila.


Assuntos
Drosophila , Mononucleotídeo de Nicotinamida , Animais , Camundongos , Drosophila/metabolismo , Mononucleotídeo de Nicotinamida/metabolismo , NAD/metabolismo , Axônios/fisiologia , Neurônios/fisiologia , Mamíferos/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Domínio Armadillo/genética , Proteínas do Domínio Armadillo/metabolismo
18.
Plant Pathol J ; 37(6): 596-606, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34897251

RESUMO

Soil-borne diseases are the major problems in mono cropping. A mixture (designated LTM-m) composed of agricultural wastes and a beneficial microorganism Streptomyces saraceticus SS31 was used as soil amendments to evaluate its efficacy for managing Rhizoctonia solani and root knot nematode (Meloidogyne incognita). In vitro antagonistic assays revealed that SS31 spore suspensions and culture broths effectively suppressed the growth of R. solani, reduced nematode egg hatching, and increased juvenile mortality. Assays using two Petri dishes revealed that LTM-m produced volatile compounds to inhibit the growth of R. solani and cause mortality to the root knot nematode eggs and juveniles. Pot and greenhouse tests showed that application of 0.08% LTM-m could achieve a great reduction of both diseases and significantly increase plant fresh weight. Greenhouse trials revealed that application of LTM-m could change soil properties, including soil pH value, electric conductivity, and soil organic matter. Our results indicate that application of LTM-m bio-organic amendments could effectively manage soil-borne pathogens.

19.
Auris Nasus Larynx ; 48(5): 834-840, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33468353

RESUMO

OBJECTIVES: Posterior benign paroxysmal positional vertigo (p-BPPV) is the most common type of BPPV, and canalith-repositioning procedure (CRP) is frequently applied for treatment. Supine to prolonged lateral position (SPLP), a simple home-based maneuver, can be performed for treatment of p-BPPV. The purpose of this study was to investigate whether combination of CRP and SPLP could be more effective in symptom alleviation compared with CRP alone and reduce times of repeated CRP for patients with p-BBPV. METHODS: A retrospective chart review enrolled 96 patients diagnosed with primary p-BPPV. Of these patients, 64 patients were included in the CRP group and 32 patients, in the CRP+SPLP group. The outcome was determined according to days required to reach negative result in Dix-Hallpike test, duration of vertigo and dizziness following the first repositioning procedure, and times of CRP performed to reach resolution of p-BPPV. RESULTS: Of patients in the CRP and CRP+SPLP groups, 38% and 16% received CRP at least twice to reach resolution, respectively (P = 0.034). Patients in the CRP group and CRP+SPLP group spent an average of 9.8 ± 6.1 days and 7.9 ± 3.4 days, respectively reaching a negative result in Dix-Hallpike test (P = 0.050). In terms of duration for relieving vertigo and dizziness, the CRP+SPLP group achieved symptom relief with shorter duration (P = 0.036 and P = 0.025, respectively). CONCLUSION: Compared with CRP alone, combination of CRP and SPLP improved the therapeutic effectiveness and shortened the duration of suffering from vertigo and dizziness in patients with p-BPPV.


Assuntos
Vertigem Posicional Paroxística Benigna/terapia , Posicionamento do Paciente/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Membrana dos Otólitos
20.
J Pers Med ; 11(5)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925911

RESUMO

The long noncoding RNA, Growth arrest-specific 5 (GAS5) plays a crucial role in the development of oral cancer. However, potential genetic variants in GAS5 that affect the susceptibility and progression of oral cancer have rarely been explored. In this study, two loci of GAS5 single nucleotide polymorphisms (SNPs) (rs145204276 and rs55829688) were genotyped by using the TaqMan allelic discrimination in 1125 oral cancer patients and 1195 non-oral-cancer individuals. After statistical analyses, the distribution of both the GAS5 SNP rs145204276 and GAS5 SNP rs55829688 frequencies were similar between the study and control groups. However, the patients with GAS5 SNP rs145204276 variants (Ins/Del or Del/Del) showed a higher tendency of moderate to poor cell differentiation of oral cancer (OR: 1.454, 95% CI: 1.041-2.031, p = 0.028). Moreover, the GAS5 SNP rs145204276 variants (Ins/Del or Del/Del) in the non-alcohol-drinking population were associated with significantly advanced tumor stage (OR: 1.500, 95% CI: 1.081-2.081, p = 0.015) and larger tumor size (OR: 1.494, 95% CI: 1.076-2.074, p = 0.016). Furthermore, individuals with the GAS5 SNP rs145204276 variant were associated with a higher expression of GAS5 in the GTEx database (p = 0.002), and the higher GAS5 level was associated with poor cell differentiation, advanced tumor stage and larger tumor size in head and neck squamous cell carcinoma from the TCGA database (all p < 0.05). In conclusion, the GAS5 SNP rs145204276 variant is related to poor-differentiation cell status in oral cancer. Besides, the presence of the GAS5 SNP rs145204276 variant is associated with a worse tumor stage and tumor size in oral cancer patients without alcohol drinking.

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