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1.
Phys Rev Lett ; 132(5): 052701, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364162

RESUMO

We demonstrate that the well-known 2.6 MeV gamma-ray emission line from thallium-208 could serve as a real-time indicator of astrophysical heavy element production, with both rapid (r) and intermediate (i) neutron capture processes capable of its synthesis. We consider the r process in a Galactic neutron star merger and show Tl-208 to be detectable from ∼12 hours to ∼ten days, and again ∼1-20 years postevent. Detection of Tl-208 represents the only identified prospect for a direct signal of lead production (implying gold synthesis), arguing for the importance of future MeV telescope missions which aim to detect Galactic events but may also be able to reach some nearby galaxies in the Local Group.

2.
Proc Natl Acad Sci U S A ; 117(35): 21008-21010, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817482

RESUMO

The Late Devonian was a protracted period of low speciation resulting in biodiversity decline, culminating in extinction events near the Devonian-Carboniferous boundary. Recent evidence indicates that the final extinction event may have coincided with a dramatic drop in stratospheric ozone, possibly due to a global temperature rise. Here we study an alternative possible cause for the postulated ozone drop: a nearby supernova explosion that could inflict damage by accelerating cosmic rays that can deliver ionizing radiation for up to [Formula: see text] ky. We therefore propose that the end-Devonian extinctions were triggered by supernova explosions at [Formula: see text], somewhat beyond the "kill distance" that would have precipitated a full mass extinction. Such nearby supernovae are likely due to core collapses of massive stars; these are concentrated in the thin Galactic disk where the Sun resides. Detecting either of the long-lived radioisotopes [Formula: see text] or [Formula: see text] in one or more end-Devonian extinction strata would confirm a supernova origin, point to the core-collapse explosion of a massive star, and probe supernova nucleosynthesis. Other possible tests of the supernova hypothesis are discussed.


Assuntos
Radiação Cósmica/efeitos adversos , Extinção Biológica , Fósseis/história , Biodiversidade , Meio Ambiente Extraterreno/química , História Antiga , Astros Celestes
3.
Entropy (Basel) ; 25(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36832627

RESUMO

Multiobjective clustering algorithm using particle swarm optimization has been applied successfully in some applications. However, existing algorithms are implemented on a single machine and cannot be directly parallelized on a cluster, which makes it difficult for existing algorithms to handle large-scale data. With the development of distributed parallel computing framework, data parallelism was proposed. However, the increase in parallelism will lead to the problem of unbalanced data distribution affecting the clustering effect. In this paper, we propose a parallel multiobjective PSO weighted average clustering algorithm based on apache Spark (Spark-MOPSO-Avg). First, the entire data set is divided into multiple partitions and cached in memory using the distributed parallel and memory-based computing of Apache Spark. The local fitness value of the particle is calculated in parallel according to the data in the partition. After the calculation is completed, only particle information is transmitted, and there is no need to transmit a large number of data objects between each node, reducing the communication of data in the network and thus effectively reducing the algorithm's running time. Second, a weighted average calculation of the local fitness values is performed to improve the problem of unbalanced data distribution affecting the results. Experimental results show that the Spark-MOPSO-Avg algorithm achieves lower information loss under data parallelism, losing about 1% to 9% accuracy, but can effectively reduce the algorithm time overhead. It shows good execution efficiency and parallel computing capability under the Spark distributed cluster.

4.
Surg Radiol Anat ; 42(2): 103-110, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31440808

RESUMO

PURPOSE: To reconstruct the three-dimensional safe triangle areas at L1-5 based on the computed tomography digital data, analyze the safe scopes for the puncture location and angles, and provide anatomic references for percutaneous lumbar discectomy. METHODS: Computed tomography data from patients and control group were imported from the database and anatomical reference parameters were measured in Mimics software. The rebuilt model was rotated clockwise along the M-axis to measure the inscribed circle radius of the safe triangle at different angles. Based on the outer diameter of the largest cannula, the safe angles were calculated. The distances between points on the projection of safe triangle-inscribed circle and the upper lumbar spinous process were measured. Similarly, while the safe triangle was on the left side, the model was contra-rotated to measure all the parameters. RESULTS: There was no significant difference between the patient and control group in both the least distance between the selected anatomical reference locations and the safe triangle-inscribed circle radius at L4-5. According to the series which had a largest cannula of 2.5 mm, the safe puncture angles increased with the descending disc levels. The optimal angles were 40°-45° for L1-2, 45°-50° for L2-3, 50° for L3-4, and 55° for L4-5 separately. The differences between genders in the distances of paired reference points were significant. CONCLUSIONS: Individual safe localization of the percutaneous puncture could be obtained by analyzing the three-dimensional relationship between the puncture localization and anatomical landmarks.


Assuntos
Discotomia Percutânea/efeitos adversos , Imageamento Tridimensional , Complicações Intraoperatórias/prevenção & controle , Vértebras Lombares/irrigação sanguínea , Vértebras Lombares/inervação , Adulto , Idoso , Simulação por Computador , Discotomia Percutânea/métodos , Feminino , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Complicações Intraoperatórias/etiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos , Nervos Espinhais/lesões , Tomografia Computadorizada por Raios X
5.
Brain Res Bull ; 194: 1-12, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36603794

RESUMO

Over-activated microglia and inflammatory mediators are found in patients with depression, while manipulation of the microglia function might represent a potential therapeutic strategy. Insulin-like growth factor 2 (IGF2) has been implicated in bacterial infections and autoimmune disorders, but the role of IGF2 on the active phenotype of microglia and neuroinflammation has not been well established. IGF2 influences in modulating microglia responding to neuroinflammation induced by lipopolysaccharide(LPS)challenge will be carefully examined. In the current study, we verified that systemic IGF2 treatment could produce an anti-depression effect in LPS-treated mice. Particularly, we found that systemic IGF2 treatment inhibited microglia over-activation and prevented its transformation to a pro-inflammatory phenotype, thereby protecting hippocampal neurogenesis. Since microglia reactive to neuroinflammation is a common feature of neuropsychiatric disorders, the discoveries from the present study may provide therapeutic innovation for these diseases.


Assuntos
Depressão , Fator de Crescimento Insulin-Like II , Microglia , Animais , Masculino , Camundongos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Doenças Neuroinflamatórias , Fenótipo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like II/farmacologia , Depressão/tratamento farmacológico
6.
Neurochem Int ; 162: 105463, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513311

RESUMO

NLRP3 inflammasome activation is implicated in irradiation-induced cognitive dysfunction. Alternate-day fasting (ADF) has been demonstrated to improve neuroinflammation as a non-pharmacological intervention. However, the exact mechanism and the anti-inflammatory effect in irradiation-induced cognitive dysfunction still need further in-depth study. The present study examined the effects of eight-week ADF on the cognitive functions of mice as well as inflammasome-mediated hippocampal neuronal loss following irradiation in mouse models of irradiation-induced cognitive deficits using seven-week-old male C57BL/6J mice. The behavioral results of novel place recognition and object recognition tasks revealed that ADF ameliorated cognitive functions in irradiation-induced cognitive dysfunction mice. ADF inhibited the expression of components of the NLRP3 inflammasome (NLRP3, ASC, and Cl.caspase-1), the downstream inflammatory factor (IL-1ß and IL-18), and apoptosis-related proteins (caspase-3) via western blotting. Furthermore, an increased number of neurons and activated astrocytes were observed in the hippocampus using immunohistochemistry and Sholl analysis, which was jointly confirmed by western blotting. According to our study, this is the first time we found that ADF improved cognitive dysfunction induced by irradiation, and the anti-inflammatory effect of ADF could be due to inhibition in NLRP3-mediated hippocampal neuronal loss by suppressing astrocyte activation.


Assuntos
Disfunção Cognitiva , Hipocampo , Jejum Intermitente , Lesões por Radiação , Animais , Masculino , Camundongos , Proteínas Reguladoras de Apoptose/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Hipocampo/patologia , Hipocampo/efeitos da radiação , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Doenças Neuroinflamatórias/terapia , Neurônios/patologia , Neurônios/efeitos da radiação , Radioterapia/efeitos adversos
7.
Behav Brain Res ; 439: 114223, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36427589

RESUMO

Pyroptosis, a newly discovered proinflammatory programmed cell death, is involved in the regulation of cognitive dysfunction, such as Alzheimer's disease. Exploring potential drug targets that prevent pyroptotic procedures might benefit the development of a cure for these diseases. In the present study, we explored whether the transient receptor potential vanilloid 4 (TRPV4) blocker HC067047 and knockdown of TRPV4 in the hippocampus could improve cognitive behavior through the inhibition of pyroptosis in a mouse model developed using systemic administration of lipopolysaccharide (LPS). We found that systemic administration of HC067047 or knockdown of hippocampal TRPV4 prevented the activation of canonical and noncanonical pyroptosis in the hippocampus of LPS-treated mice. Consistent with the inhibition of the hippocampal pyroptosis pathway, a knockdown of hippocampal TRPV4 lowered expression of TNF-α, IL-1ß, IL-18, and IL-6. Furthermore, we verified that the main pyroptosis cell type might be a neuron, indicated by reduced neuronal marker expression. Mechanically, we also found that knockdown of hippocampal TRPV4 might inhibit phosphorylation of CamkⅡα which results in NFκb mediated inflammasome reduction in the hippocampus of LPS-treated mice. More interestingly, mice intraperitoneally injected with HC067047 or the hippocampus injected with TRPV4 shRNA showed improved cognitive behavior, as indicated by the enhanced discrimination ratio in the NORT, NOPT, and SNPT. Collectively, we consider that HC067047 might be a small molecular drug that prevents pyroptosis, and TRPV4 could be an effective therapeutic target for preventing pyroptosis-induced cognitive dysfunction.


Assuntos
Antineoplásicos , Disfunção Cognitiva , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Piroptose , Canais de Cátion TRPV , Inflamassomos/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Antineoplásicos/farmacologia , Hipocampo/metabolismo
8.
Neuropharmacology ; 233: 109560, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37094770

RESUMO

Gonadotropin-releasing hormone (GnRH) is at the head of the neuroendocrine reproductive axis. However, the non-reproductive functions of GnRH expressed in various tissues, including hippocampus, are still not known. Here, we unveil a previously unknown effect of GnRH, which mediates depression-like behaviors through the modulation of microglia function during immune challenge. Specifically, we found that either systemic treatment with GnRH agonist or over-expression of endogenous hippocampal GnRH via viral tool abolished the depression-like behavior after LPS challenges in mice. And the anti-depressant of GnRH was dependent on the hippocampal GnRHR signaling, since antagonizing GnRHR by drug treatment or by hippocampal GnRHR knockdown could block the antidepressant-effect of GnRH agonist. Interestingly, we found that the peripheral GnRH treatment prevented the microglia activation mediated inflammation in the hippocampus of mice. In light of the research findings presented here, we propose that, at least in the hippocampus, GnRH appears to act on GnRHR to regulate higher order non-reproductive functions associated with the microglia mediated neuroinflammation. These findings also provide insights into the function and cross-talk of GnRH, a known neuropeptide hormone, in neuro-immune response.


Assuntos
Depressão , Lipopolissacarídeos , Masculino , Camundongos , Animais , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Hormônio Liberador de Gonadotropina/farmacologia , Transdução de Sinais , Antidepressivos/farmacologia
9.
Neuropharmacology ; 201: 108834, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34637786

RESUMO

Inflammation is a crucial component that contributes to the pathogenesis of major depressive disorder. It has been revealed that the nonselective cation channel transient receptor potential vanilloid 4 (TRPV4) profoundly affects a variety of physiological processes, including inflammation. However, its roles and mechanisms in LPS-induced depression are still unclear. Here, for the first time, we found that there was a significant increase in TRPV4 in the hippocampus in a depression mouse model induced by LPS. TRPV4 inhibitor HC067047 or knockdown the hippocampal TRPV4 with TRPV4 shRNA could effectively rescue the aberrant behaviors. Furthermore, TRPV4 inhibitor HC067047 reduced the activation of astrocyte and microglia, decreased expression of CaMKII-NLRP3 inflammasome and increased the expression of neurogenesis marker DCX in the hippocampus. In addition, enhanced neuroinflammation in the serum was also reversed by TRPV4 inhibitor HC067047. Thus, we consider that TRPV4 has an important role in contributing to the depression-like behavior following LPS-induced systemic inflammation.


Assuntos
Antidepressivos , Depressão , Lipopolissacarídeos , Pirróis , Canais de Cátion TRPV , Animais , Masculino , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Astrócitos/metabolismo , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Proteína Duplacortina/metabolismo , Hipocampo/metabolismo , Inflamassomos/metabolismo , Lipopolissacarídeos/efeitos adversos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Neurogênese/genética , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/fisiologia , Pirróis/química , Pirróis/farmacologia , Pirróis/uso terapêutico
10.
Neurosci Lett ; 721: 134828, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32044392

RESUMO

The circuitry associated with the visual cortex is particularly sensitive to experiences during the early stages of life, which are collectively known as critical periods. Critical period of ocular dominance plasticity is regulated by both environmental and genetic factors. Previous studies demonstrated that IGF-1 significantly influenced the regulation of visual cortex synaptic plasticity. IGF-2 can reportedly regulate synapse formation, dendritic spine maturation, and memory consolidation in rodents. Association between IGF-2 and the regulation of visual cortex synaptic plasticity remains unclear. Here, we first aimed to elucidate the normal expression patterns of IGF-2 and its laminar expression pattern during the process of visual cortex development in mice. This confirmed that IGF-2 may influence the regulation of ocular dominance plasticity in mice. We further elucidated the role of IGF-2 in the regulation of visual cortex synaptic plasticity by examining the effect of monocular deprivation (MD) on IGF-2 expression in the visual cortex. Interestingly, we observed that MD remarkably reduced IGF-2 expression in the visual cortex. Rodents reared in an enriched environment, with enhanced sensory, motor, and social experiences, were capable of effectively accelerating the development of the visual system and could restore normal visual acuity. Although the enriched environment facilitated the restoration of normal visual acuity in the MD mice, IGF-2 expression levels in the visual cortex remained unchanged. Therefore, we considered the possibility that IGF-2 may have a different role with regard to the modulation of plasticity in the visual cortex of the mice, which we aim to study in the future.


Assuntos
Fator de Crescimento Insulin-Like II/biossíntese , Privação Sensorial/fisiologia , Visão Monocular/fisiologia , Córtex Visual/crescimento & desenvolvimento , Córtex Visual/metabolismo , Animais , Expressão Gênica , Fator de Crescimento Insulin-Like II/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Environ Toxicol Chem ; 27(1): 182-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18092879

RESUMO

Atrazine, a highly toxic herbicide, is frequently detected in surface water because of its heavy application. Algae are among the aquatic organisms most susceptible to atrazine pollution in water. In the present study, the aquatic alga Chlorella vulgaris Beijerinck was chosen to assess the acute toxicity of atrazine (48-96 h) in terms of gene transcription and physiological changes. A real-time polymerase chain reaction (PCR) assay was used to quantify transcript levels of three photosystem genes in C. vulgaris. The diel patterns for regulation of the psaB (photosystem I reaction center protein subunit B), psbC (an integral membrane protein component of photosystem II), and rbcL (large subunit of ribulose-1,5-bisphosphate carboxylase oxygenase) gene transcripts were successfully quantified. Results showed that atrazine reduced the transcript abundances of three target genes and that the abundances decreased with increasing atrazine concentration. The determined smallest transcript levels of psaB, psbC, and rbcL, which occurred at the highest atrazine concentration tested (400 mug/L), were only 34.6, 34.6, and 8.1%, respectively, of the control sample value. Exposure to atrazine increased the level of malondialdehyde by 1.74-fold (the highest value) in C. vulgaris, suggesting potential oxidative damage to the alga. The activities of antioxidation enzymes (e.g., superoxide dismutase, peroxidase, and catalase) also increased markedly in the presence of atrazine, with maximum increases of 1.82-, 1.59-, and 2.31-fold, respectively. These elevated activities may help to alleviate the oxidative damage. Our results demonstrate that atrazine is highly toxic to this alga and that real-time PCR is an efficient technique for assessing the toxicity of xenobiotic compounds in algae.


Assuntos
Atrazina/efeitos adversos , Chlorella vulgaris/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Poluentes da Água/efeitos adversos , Eucariotos/efeitos dos fármacos , Herbicidas/efeitos adversos , Oxirredutases/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/genética , RNA Mensageiro/análise , Transcrição Gênica/efeitos dos fármacos
12.
Adv Clin Exp Med ; 26(8): 1275-1281, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29264887

RESUMO

BACKGROUND: Gliomas are the most common primary brain tumor in adults. Many studies have revealed associations between the rs4295627 polymorphism in the coiled-coil domain containing 26 (CCDC26) gene and the risk of glioma. However, the conclusions are still unclear because some studies have reported inconsistent results. OBJECTIVES: The aim of the present meta-analysis was to determine the relationship and quantitatively evaluate the effect of the rs4295627 polymorphism on the risk of glioma. MATERIAL AND METHODS: Data was extracted from PubMed, EMBASE and Google Scholar, with the most recent search up to December, 2015. Odds ratios (OR) and their 95% CIs were used to evaluate the effect of CCDC26 rs4295627 polymorphisms on glioma. A test of heterogeneity and an assessment of publication bias were also performed. RESULTS: A total of 11 studies (8292 cases and 12,419 controls) were selected for this meta-analysis. Significant associations were observed in all genetic analysis models (G vs T: OR = 1.26, 95% CI = 1.12-1.43; GG vs TT: OR = 1.72, 95% CI = 1.24-2.39; GT vs TT: OR = 1.33, 95% CI = 1.24-1.42; GG + GT vs TT: OR = 1.36, 95% CI = 1.20-1.53; GG vs GT + TT: OR = 1.65, 95% CI = 1.18-2.29, respectively). CONCLUSION: The results of the present study clearly show that the G allele of the rs4295627 polymorphism significantly increases the risk of glioma. Nevertheless, well-designed large-scale studies are needed to further evaluate the effect of the rs4295627 polymorphism on different types or degrees of glioma in different ethnic groups as well as to measure the combined effects on glioma risk.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Encefálicas/etiologia , Genótipo , Glioma/etiologia , Humanos , Viés de Publicação , RNA Longo não Codificante , Risco
14.
Neural Regen Res ; 10(1): 141-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25788935

RESUMO

Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of the humerus, and the length of the vessels accompanying the ulnar nerve in the superior ulnar collateral artery, the inferior ulnar collateral artery, and the posterior ulnar recurrent artery were measured. Anterior transposition of the vascularized ulnar nerve was performed to treat cubital tunnel syndrome. The most appropriate distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions was 1.8 ± 0.6 cm (1.1-2.5 cm), which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve.

15.
Neural Regen Res ; 7(1): 18-23, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25806053

RESUMO

The present study examined changes in retinal tyrosine hydroxylase (TH) expression in rats having undergone optic nerve transection and housed under a normal day/night cycle or in the dark. The aim was to investigate the effects of amacrine cells on axonal regeneration in retinal ganglion cells and on the synapses that transmit visual signals. The results revealed that retinal TH expression gradually decreased following optic nerve transection in rats housed under a normal day/night cycle, reaching a minimum at 5 days. In contrast, retinal TH expression decreased to a minimum at 1 day following optic nerve transection in dark reared rats, gradually increasing afterward and reaching a normal level at 5-7 days. The number of TH-positive synaptic particles correlated with the TH levels, indicating that dark rearing can help maintain TH expression during the synaptic degeneration stage (5-7 days after optic nerve injury) in retinal amacrine cells.

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