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Current studies have presented conflicting findings regarding the associations between light at night (LAN) exposure and the risk of overweight/obesity, hypertension, and diabetes. Our study systematically summarized the evidence of the association between LAN exposure and the risk of overweight/obesity, hypertension, and diabetes. We searched five databases (PubMed, Web of Science, Embase, Scopus, and Cochrane) for observational studies published up to 1 August 2023. The pooled odds ratio (ORs) and 95% confidence intervals (CIs) were estimated by random-effects models for the association. Eighteen studies were included in the meta-analysis. Compared with the group with the lowest level of LAN, the group with the highest level of LAN is associated with an increased risk of overweight/obesity (pooled OR = 1.19, 95%CI: 1.13-1.26), hypertension (pooled OR: 1.86, 95% CI:1.28-2.72), and diabetes (pooled OR = 1.21, 95%CI: 1.07-1.31). Our meta-analysis demonstrated LAN exposure is associated with increased risk of overweight/obesity, hypertension, and diabetes.
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Recently, microalgae had received extensive attention for carbon capture and utilization. But its overall efficiency still could not reach a satisfactory degree. Artificial photosynthesis showed better efficiency in the conversion of carbon dioxide. However, artificial photosynthesis could generally only produce C1-C3 organic matters at present. Some studies showed that heterotrophic microalgae can efficiently synthesize high value organic matters by using simple organic matter such as acetate. Therefore, the combination of artificial photosynthesis with heterotrophic microalgae culture showed great potential for efficient carbon capture and high-value organic matter production. This article systematically analyzed the characteristics and challenges of carbon dioxide conversion by microalgae and artificial photosynthesis. On this basis, the coupling mode and development trend of artificial photosynthesis combined with microalgae culture were discussed. In summary, the combination of artificial photosynthesis and microalgae culture has great potential in the field of carbon capture and utilization, and deserves further study.
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Dióxido de Carbono , Microalgas , Fotossíntese , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Biotecnologia/métodos , Carbono/metabolismoRESUMO
OBJECTIVES: To explore research hotspots and theme trends in artificial intelligence in nurse education using bibliometric analysis. DESIGN: Bibliometric analysis. DATA SOURCES: Literature from the Web of Science Core Collection from the time of construction to October 31, 2023 was searched. REVIEW METHODS: Analyses of countries, authors, institutions, journals, and keywords were conducted using Bibliometrix (based on R language), CiteSpace, the online analysis platform (bibliometric), Vosviewer, and Pajek. RESULTS: A total of 135 articles with a straight upward trend over the last three years were retrieved. By fitting the curve R2 = 0.6022 (R2 > 0.4), we predicted that the number of annual articles is projected to grow in the coming years. The United States (n = 38), the National University of Singapore (n = 16), Professor Jun Ota (n = 8), and Nurse Education Today (n = 14) are the countries, institutions, authors, and journals that contributed to the most publications, respectively. Collaborative network analysis revealed that 32 institutional and 64 author collaborative teams were established. We identified ten high-frequency keywords and nine clusters. We categorized the research hotspots of artificial intelligence in nurse education into three areas: (1) Artificial intelligence-enhanced simulation robots, (2) machine learning and data mining, and (3) large language models based on natural language processing and deep learning. By analyzing the temporal and spatial evolution of keywords and burst detection, we found that future research trends may include (1) expanding and deepening the application of AI technology, (2) assessment of behavioral intent and educational outcomes, and (3) moral and ethical considerations. CONCLUSIONS: Future research should be conducted on technology applications, behavioral intent, ethical policy, international cooperation, interdisciplinary cooperation, and sustainability to promote the continued development and innovation of AI in nurse education.
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BACKGROUND: This study aims to explore the association between a healthy lifestyle and abnormal ambulatory blood pressure (ABP) in Chinese youths. METHODS: A school-based sample of 1,296 college students was investigated. A lifestyle score was calculated by synthesizing 5 lifestyle factors, including smoking, alcohol consumption, diet, physical activity, and sleeping. The total score ranged from 0 to 5, with a higher score indicating a healthier lifestyle. This score was then divided into 3 categories representing low adherence to a healthy lifestyle (0-2), medium adherence (3), and high adherence (4-5). Abnormal 24-hour blood pressure (BP) was defined as systolic BP (SBP)â ≥â 130 mm Hg and/or diastolic BP (DBP)â ≥â 80 mm Hg. Abnormal daytime BP was determined as daytime SBPâ ≥â 135 mm Hg and/or DBPâ ≥â 85 mm Hg, while abnormal nighttime BP was characterized as nighttime SBPâ ≥â 120 mm Hg and/or DBPâ ≥â 70 mm Hg. We assessed the associations using the binomial regression model. RESULTS: Mean age was 18.81 years, and 74.5% were women. The prevalence of abnormal 24-hour BP, daytime BP, and nighttime BP are 4.2%, 3.7%, and 9.0%, respectively. We found that participants with a high level of adherence to a healthy lifestyle had a significantly lower prevalence of abnormal 24-hour BP [prevalence ratios (PR)â =â 0.15, 95% CI: 0.05, 0.48] and abnormal daytime BP (PRâ =â 0.16, 95%CI: 0.05, 0.52), when compared to those with a low level of adherence and after adjusting for the potential covariates. CONCLUSIONS: A healthier lifestyle is associated with a better ambulatory BP profile among youths.
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Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Ritmo Circadiano , Estilo de Vida Saudável , Hipertensão , Humanos , Feminino , Masculino , Adolescente , Estudos Transversais , China/epidemiologia , Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Hipertensão/epidemiologia , Hipertensão/diagnóstico , Adulto Jovem , Exercício Físico , Prevalência , Fatores de Risco , Consumo de Bebidas Alcoólicas/epidemiologia , Fumar/epidemiologia , Sono , Comportamento de Redução do Risco , Fatores de Tempo , População do Leste AsiáticoRESUMO
Chironomids are one of the most abundant aquatic insects and are widely distributed in various biological communities. However, the lack of high-quality genomes has hindered our ability to study the evolution and ecology of this group. Here, we used Nanopore long reads and Hi-C data to produce two chromosome-level genomes from mixed genomic data. The genomes of Smittia aterrima (SateA) and Smittia pratorum (SateB) were assembled into three chromosomes, with sizes of 78.45 Mb and 71.56 Mb, scaffold N50 lengths of 25.73 and 23.53 Mb, and BUSCO completeness of 98.5% and 97.8% (n = 1,367), 5.68 Mb (7.24%) and 1.94 Mb (2.72%) of repetitive elements, and predicted 12,330 (97.70% BUSCO completeness) and 11,250 (97.40%) protein-coding genes, respectively. These high-quality genomes will serve as valuable resources for comprehending the evolution and environmental adaptation of chironomids.
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Chironomidae , Genoma de Inseto , Animais , Chironomidae/genética , Genômica , Anotação de Sequência Molecular , Filogenia , Sequências Repetitivas de Ácido Nucleico , Cromossomos de InsetosRESUMO
BACKGROUND: The relationship between chronotype and anxiety, depression, and insomnia was inconsistent. We aimed to assess the association between chronotype and mental health and the potential moderating effect of age and socioeconomic status (SES). METHODS: A multi-stage sampling cross-sectional study with 12,544 adults was conducted. Chronotype, anxiety, depression, and insomnia were investigated by 5-item Morning and Evening, 7-item Generalized Anxiety Disorder, 9-item Patient Health, and the 7-item Insomnia Severity Index Questionnaires. Logistic regression was conducted. RESULTS: The predominant chronotype was morning chronotype (69.2 %), followed by 27.6 % intermediate and 3.2 % evening chronotype. The prevalence of anxiety, depression, and insomnia was 0.7 %, 1.9 %, and 9.6 %, respectively. Compared with intermediate chronotype, morning chronotype participants had a lower risk of anxiety (OR = 0.28,95%CI:0.18-0.44), depression (OR = 0.54,95%CI:0.41-0.72) and insomnia (OR = 0.67,95%CI:0.58-0.77), while evening chronotype participants had a higher risk of depression (OR = 1.98,95%CI:1.06-3.71) but not anxiety or insomnia. Interactions between chronotype with age and SES on insomnia (Pinteraction < 0.05) were found. A more profound association between morning chronotype and insomnia was observed in <65 years participants (OR = 0.59,95%CI:0.50-0.71) and those with monthly household income ≥10,000yuan (OR = 0.21,95%CI:0.12-0.35), compared with their counterparts. LIMITATIONS: The cross-sectional design limited causal conclusions. Only adults were included; the findings could not be generalized to children. CONCLUSIONS: The morning chronotype might be protective for anxiety, depression, and insomnia, while the evening chronotype might be a risk factor for depression. Future studies are needed to assess the efficacy of chronotype-focused intervention for mental health. Insomnia prevention efforts should pay more attention to the elderly and those with lower incomes.
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Distúrbios do Início e da Manutenção do Sono , Adulto , Criança , Humanos , Idoso , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Cronotipo , Ansiedade/epidemiologia , Transtornos de Ansiedade , China/epidemiologia , Inquéritos e Questionários , Sono , Ritmo CircadianoRESUMO
The synthesis of chiral α-azaheteroaryl oxiranes via enantioselective catalysis is a formidable challenge due to the required complex stereoselectivity and diverse N-heterocyclic structures. These compounds play a crucial role in developing bioactive molecules, where precise chirality significantly influences biological activity. Here we show that using chiral phosphoric acid as a catalyst, our method efficiently addresses these challenges. This technique not only achieves high enantio- and diastereoselectivity but also demonstrates superior chemo- and stereocontrol during the epoxidation of alkenyl aza-heteroarenes. Our approach leverages a synergistic blend of electrostatic and hydrogen-bonding interactions, enabling the effective activation of both substrates and hydrogen peroxide. The resulting chiral oxiranes exhibit enhanced diversity and functionality, aiding the construction of complex chiral azaaryl compounds with contiguous stereocenters. Kinetic and density functional theory studies elucidate the mechanism, highlighting chiral phosphoric acid's pivotal role in this intricate enantioselective process.
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Motor imagery (MI) is a high-level cognitive process that has been widely applied to clinical rehabilitation and brain-computer interfaces (BCIs). However, the decoding of MI tasks still faces challenges, and the neural mechanisms underlying its application are unclear, which seriously hinders the development of MI-based clinical applications and BCIs. Here, we combined EEG source reconstruction and Bayesian nonnegative matrix factorization (NMF) methods to construct large-scale cortical networks of left-hand and right-hand MI tasks. Compared to right-hand MI, the results showed that the significantly increased functional network connectivities (FNCs) mainly located among the visual network (VN), sensorimotor network (SMN), right temporal network, right central executive network, and right parietal network in the left-hand MI at the ß (13-30Hz) and all (8-30Hz) frequency bands. For the network properties analysis, we found that the clustering coefficient, global efficiency, and local efficiency were significantly increased and characteristic path length was significantly decreased in left-hand MI compared to right-hand MI at the ß and all frequency bands. These network pattern differences indicated that the left-hand MI may need more modulation of multiple large-scale networks (i.e., VN and SMN) mainly located in the right hemisphere. Finally, based on the spatial pattern network of FNC and network properties, we propose a classification model. The proposed model achieves a top classification accuracy of 78.2% in cross-subject two-class MI-BCI tasks. Overall, our findings provide new insights into the neural mechanisms of MI and a potential network biomarker to identify MI-BCI tasks.
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Algoritmos , Teorema de Bayes , Interfaces Cérebro-Computador , Eletroencefalografia , Imaginação , Rede Nervosa , Humanos , Masculino , Imaginação/fisiologia , Eletroencefalografia/métodos , Adulto Jovem , Adulto , Feminino , Rede Nervosa/fisiologia , Mãos/fisiologia , Córtex Cerebral/fisiologia , Lateralidade Funcional/fisiologia , Movimento/fisiologiaRESUMO
Limb-girdle muscular dystrophies are a group of extremely heterogenous neuromuscular disorders that manifest with gradual and progressive weakness of both proximal and distal muscles. Autosomal dominant limb-girdle muscular dystrophy (LGMDD4) or calpainopathy is a very rare form of myopathy characterized by weakness and atrophy of both proximal and distal muscles with a variable age of onset. LGMDD4 is caused by germline heterozygous mutations of the calpain 3 (CAPN3) gene. Patients with LGMDD4 often show extreme phenotypic heterogeneity; however, most patients present with gait difficulties, increased levels of serum creatine kinase, myalgia and back pain. In the present study, a 16-year-old male patient, clinically diagnosed with LGMDD4, was investigated. The proband had been suffering from weakness and atrophy of both of their proximal and distal muscles, and had difficulty walking and standing independently. The serum creatine kinase levels (4,754 IU/l; normal, 35-232 IU/l) of the patient were markedly elevated. The younger sister and mother of the proband were also clinically diagnosed with LGMDD4, while the father was phenotypically normal. Whole exome sequencing identified a heterozygous novel splice-site (c.2440-1G>A) mutation in intron 23 of the CAPN3 gene in the proband. Sanger sequencing confirmed that this mutation was also present in both the younger sister and mother of the proband, but the father was not a carrier of this mutation. This splice-site (c.2440-1G>A) mutation causes aberrant splicing of CAPN3 mRNA, leading to the skipping of the last exon (exon 24) of CAPN3 mRNA and resulting in the removal of eight amino acids from the C-terminal of domain IV of the CAPN3 protein. Hence, this splice site mutation causes the formation of a truncated CAPN3 protein (p.Trp814*) of 813 amino acids instead of the wild-type CAPN3 protein that consists of 821 amino acids. This mutation causes partial loss of domain IV (PEF domain) in the CAPN3 protein, which is involved in calcium binding and homodimerization; therefore, this is a loss-of-function mutation. Relative expression of the mutated CAPN3 mRNA was reduced in comparison with the wild-type CAPN3 mRNA in the proband, and their younger sister and mother. This mutation was also not present in 100 normal healthy control individuals of the same ethnicity. The present study reported the first case of CAPN3 gene-associated LGMDD4 in the Chinese population.
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Acute Myocardial Infarction (AMI) after Percutaneous Coronary Intervention (PCI) often requires stent implantation leading to cardiovascular injury and cytokine release. Stent implantation induces cytokines production including TNFα, Hs-CRP, IL-1ß, IL2 receptor, IL6, IL8, and IL10, but their co-release is not extensively established. In 311 PCI patients with Drug-Eluting Stent (DES) implantation, we statistically evaluate the correlation of these cytokines release in various clinical conditions, stent numbers, and medications. We observed that TNFα is moderately correlated with IL-1ß (r2 = 0.59, p = 0.001) in diabetic PCI patients. Similarly, in NSTEMI (Non-ST Segment Elevation) patients, TNFα is strongly correlated with both IL-1ß (r2 = 0.97, p = 0.001) and IL8 (r2 = 0.82, p = 0.001). In CAD (Coronary Artery Disease)-diagnosed patients TNFα is highly correlated (r2 = 0.84, p = 0.0001) with IL8 release but not with IL-1ß. In patients with an increased number of stents, Hs-CRP is significantly coupled with IL8 > 5 pg/ml (t-statistic = 4.5, p < 0.0001). Inflammatory suppressor drugs are correlated as TNFα and IL8 are better suppressed by Metoprolol 23.75 (r2 = 0.58, p < 0.0001) than by Metoprolol 11.87 (r2 = 0.80, p = 0.5306). Increased TNFα and IL-1ß are better suppressed by the antiplatelet drug Brilinta (r2 = 0.30, p < 0.0001) but not with Clopidogrel (r2 = 0.87, p < 0.0001). ACI/ARB Valsartan 80 (r2 = 0.43, p = 0.0011) should be preferred over Benazepril 5.0 (r2 = 0.9291, p < 0.0001) or Olmesartan (r2 = 0.90, p = 0.0001). Thus, the co-release of IL-1ß, IL8 with TNFα, or only IL8 with TNFα could be a better predictor for the outcome of stent implantation in NSTEMI and CAD-diagnosed AMI patients respectively. Cytokine suppressive medications should be chosen carefully to inhibit further cardiovascular damage.
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Stents Farmacológicos , Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Infarto do Miocárdio sem Supradesnível do Segmento ST/cirurgia , Citocinas , Metoprolol , Fator de Necrose Tumoral alfa , Antagonistas de Receptores de Angiotensina , Proteína C-Reativa , Interleucina-8 , Resultado do Tratamento , Inibidores da Enzima Conversora de Angiotensina , Infarto do Miocárdio/cirurgia , Infarto do Miocárdio/etiologiaRESUMO
This study was designed to screen 6 lysosomal storage diseases (LSDs) in neonates using tandem mass spectrometry (MS/MS), and establish cutoff values for these LSDs with 3000 dried blood spots (DBS) samples. Cutoff values for α-L-iduronidase (IDUA), α-galactosidase (GLA), acid beta glucosidase (ABG), ß-galactocerebrosidase (GALC), acid sphingomyelinase (ASM), and acid alpha glucosidase (GAA) were as follows: GLA, > 2.06 µmol/L·h; ABG, > 1.78 µmol/L·h; ASM, > 0.99 µmol/L·h; IDUA, > 1.33 µmol/L·h; GALC, > 0.84 µmol/L·h; and GAA, > 2.06 µmol/L·h. There were 30 positives in initial MS/MS screening test, and 15 samples were still positive with repeat testing. Their parents/guardians were recontacted and DBS samples were collected again for test. Only 1 child showed abnormal GAA enzyme activity after recontacting process, and was diagnosed with Pompe disease after genetic screening. Eventually, cutoff values of 6 specific enzyme activities were established and MS/MS is effective for early LSDs screening.
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AIM:To investigate the protective effect of procyanidins on the PC 12 cells exposed to Aβ25-35and the mechanisms.METHODS:Aβ25-35at 25 μmol/L was used to treat the PC12 cells for 48 h, and the PC12 cells were pretreated with procyanidins at 25,50 and 100 mg/L for 24 h.The cell vitality was measured by MTT assay.The content of reactive oxygen species(ROS)was detected by DCFH-DA staining.The change of mitochondrial membrane potential was examined by JC-10 staining.The apoptosis was analyzed by flow cytometry with Annexin V /PI double staining.The protein levels of activated caspase-3 was determined by Western blot.RESULTS:Under the exposure of the PC12 cells to Aβ25-35,procyanidins increased the cell viability,reduced intracellular ROS level, prevented mitochondrial membrane po-tential decline,attenuated the caspase-3 activation and inhibited the apoptosis of PC 12 cells(P<0.05 or P<0.01). CONCLUSION:Procyanidins have a significant protective effect on the PC 12 cells exposed to Aβ25-35.Its mechanism may be related to removing intracellular ROS induced by A β25-35, relieving the damage to the mitochondrial membrane, and thereby inhibiting cell apoptosis.
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@#Tissue engineering has been applied to induce pulp-dentin complex regeneration, and proposed the concept of regenerative endodontics. As a new subject in stomatology, regenerative endodontics promotes root development and pulp regeneration with the combination of dental stem cells, biomaterial scaffolds and growth factors. Clinically, pulp regenerative technique has been used to treat necrosis and periapical periodontitis of immature permanent teeth. Numerous case reports and studies have proved the possibility of pulp regeneration, and regenerative endodontics will become a potential new treatment alternative of dental pulp diseases for dental clinician. In the present paper, we will summarize and analyze the current process and prospective of regenerative endodontics.
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ABSTRACT Background: Alternative splicing (AS), which plays an important role in gene expression and functional regulation, has been analyzed on genome-scale by various bioinformatic approaches based on RNA-seq data. Compared with the huge number of studies on mouse, the AS researches approaching the rat, whose genome is intermedia between mouse and human, were still limited. To enrich the knowledge on AS events in rodents' brain, we perfomed a comprehensive analysis on four transcriptome libraries (mouse cerebrum, mouse cerebellum, rat cerebrum, and rat cerebellum), recruiting high-throughput sequencing technology. An optimized exon-exon junction library approach was introduced to adapt the longer RNA-seq reads and to improve mapping efficiency. Results: In total, 7,106 mouse genes and 2,734 rat genes were differentially expressed between cerebrum and cerebellum, while 7,125 mouse genes and 1,795 rat genes exhibited varieties on transcript variant level. Only half of the differentially expressed exon-exon junctions could be reflected at gene expression level. Functional cluster analysis showed that 32 pathways in mouse and 9 pathways in rat were significantly enriched, and 6 of them were in both. Interestingly, some differentially expressed transcript variants did not show difference on gene expression level, such as PLCβ1 and Kcnma1. Conclusion: Our work provided a case study of a novel exon-exon junction strategy to analyze the expression of genes and isoforms, helping us understand which transcript contributes to the overall expression and further functional change.
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<p><b>BACKGROUND AND OBJECTIVE</b>Radiotherapy (RT) is a major non-surgical modality in the comprehensive treatment for colorectal adenocarcinoma. The radioresistance of cancer stem cells (CSCs) is a key factor that influences therapeutic effectiveness. This study was to investigate the effects of specific chromosome structure and histone modification in CSCs in colorectal adenocarcinoma radioresistance.</p><p><b>METHODS</b>Samples were collected from resected human colorectal adenocarcinomas. Subcutaneous colorectal cancer model was established in nude mice. Immunohistochemistry showed that xenografts generated from bulk colorectal cancer cells resembled the original tumor specimen. Flow cytometry was performed to sort CSCs (CD133+) and non-CSCs (CD133-) from both resected samples of colorectal adenocarcinoma and xenograft before and after high single-dose radiation. The markers labeling heterochromatin (H3K9me3, HP1-alpha and H3K4me1) and euchromatin (H3K4me3) in CD133+ and CD133- nucleus were detected by immunofluorescence.</p><p><b>RESULTS</b>There was distinct difference in chromatin structure between colorectal CSCs (CD133+) and non-CSCs (CD133-). The chromatin displayed compact patches in CD133+ nucleus, but loosely latticed structure in CD133- nucleus; immunofluorescence verified that the compact patches existing in CSCs was generated from heterochromatin construction. In addition, the vacuole-like defect in heterochromatin regions of CSCs was observed within 24 h after exposure to 10 gray (Gy) single-dose RT. Interestingly, this phenomenon was repaired from 96 h, and recovered to dense plaque structure in heterochromatin regions of CSCs after 144 h. However, no significant difference in non-CSCs was observed after RT exception for a loose chromatin structure.</p><p><b>CONCLUSIONS</b>CSCs play a role in radiosensitivity in colorectal cancer. The mechanism may be related to heterochromatin formation and histone methylation.</p>
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Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Antígeno AC133 , Adenocarcinoma , Patologia , Radioterapia , Antígenos CD , Metabolismo , Núcleo Celular , Genética , Patologia , Neoplasias Colorretais , Patologia , Radioterapia , Glicoproteínas , Metabolismo , Heterocromatina , Metabolismo , Histonas , Metabolismo , Metilação , Camundongos Nus , Transplante de Neoplasias , Células-Tronco Neoplásicas , Patologia , Efeitos da Radiação , Aceleradores de Partículas , Peptídeos , Metabolismo , Doses de Radiação , Tolerância a RadiaçãoRESUMO
<p><b>OBJECTIVE</b>To evaluate the effect of the pulsed Nd: YAG laser irradiation on the survival rate of human penodontal ligament fibroblast (PDLF) at different power and irradiation time settings, and to compare the morphological change of cells before and after irradiation.</p><p><b>METHODS</b>The cells were cultured and placed into the 96-well tissue culture plates. Cells were divided into groups according to the irradiation time (10 s, 20 s, 40 s, 60 s) and the output energy (0.5 W, 1.0 W, 1.5 W, 2.0 W, 2.5 W). After the irradiation, the cell number were counted and the survival rates were calculated. The correlation between the survival rate and irradiation time as well as power output was analyzed.</p><p><b>RESULTS</b>No significant reduction of survival rates were found in 10 s group, as well as in 20 s group with 0.5 W, 1.0 W setting. The increase of the power output and increase of the irradiation time caused significant reduction of cell survival rate (P <0.05). The irradiation time was more relevant to this reduction than the power output.</p><p><b>CONCLUSION</b>It indicates that the laser irradiation may cause damage to PDLF and decrease the cell survival rate. The irradiation time is more related to this effect than the power output.</p>
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Humanos , Fibroblastos , Lasers , Lasers de Estado Sólido , Ligamento PeriodontalRESUMO
Objective To investigate the brain mechanisms of aging of the visual attention. Methods Through the precue-target visual search paradigm using the event-related potentials technique,16 young and 16 elderly subjects participated the electrophysiological experiment.The background was comprised of three homocentric black circles and eight English capital letters consisted of each circle.The letter “T” was designed as the target stimulus.T was a target only when it located the circle clued to the same size of the precue.For example,when the cue was the “large”,“T” may appear within 3 circles.When the cue was the “median”,“T” may appear within either the median or small circles.When the cue was small,the target “T” may appear only within the small circle. Results The reaction time of the two groups of subjects became quick with the reduction of the cue scale,while the amplitudes of P1 and N1 components of event-related potentials increased with the decrease of the cue scale.Old subjects showed longer response time than did young subjects,and the posterior P1 component was enhanced significantly and N1 component was inhibited obviously.The P2 component was manifested as significantly inhibitory effect not only in the amplitude but also in the abnormal and unstable waveform.Conclusions The cognitive function of elderly subjects declines in the research of target stimuli,which suggests that the age-related changes could lead to deficit in the posterior area of the brain to visual spatial attention (involuntary attention).