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There is a lack of evidence from cohort studies on the causal association of long-term exposure to ambient fine particulate matter (PM2.5) and its chemical components with the risk of nasopharyngeal carcinoma (NPC) recurrence. Based on a 10-year prospective cohort of 1184 newly diagnosed NPC patients, we comprehensively evaluated the potential causal links of ambient PM2.5 and its chemical components including black carbon (BC), organic matter (OM), sulfate (SO4 2-), nitrate (NO3 -), and ammonium (NH4 +) with the recurrence risk of NPC using a marginal structural Cox model adjusted with inverse probability weighting. We observed 291 NPC patients experiencing recurrence during the 10-year follow-up and estimated a 33% increased risk of NPC recurrence (hazard ratio [HR]: 1.33, 95% confidence interval [CI]: 1.02-1.74) following each interquartile range (IQR) increase in PM2.5 exposure. Each IQR increment in BC, NH4 +, OM, NO3 -, and SO4 2- was associated with HRs of 1.36 (95%CI: 1.13-1.65), 1.35 (95%CI: 1.07-1.70), 1.33 (95%CI: 1.11-1.59), 1.32 (95%CI: 1.06-1.64), 1.31 (95%CI: 1.08-1.57). The elderly, patients with no family history of cancer, no smoking history, no drinking history, and those with severe conditions may exhibit a greater likelihood of NPC recurrence following exposure to PM2.5 and its chemical components. Additionally, the effect estimates of the five components are greater among patients who were exposed to high concentration than in the full cohort of patients. Our study provides solid evidence for a potential relationship between long-term exposure to PM2.5 and its components and the risk of NPC recurrence.
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Evidence of the potential causal links between long-term exposure to particulate matters (PM, i.e., PM1, PM2.5, and PM1-2.5) and T2DM mortality based on large cohorts is limited. In contrast, the existing evidence usually suffers from inherent bias with the traditional association assessment. A prospective cohort of 580,757 participants in the southern region of China were recruited during 2009 and 2015 and followed up through December 2020. PM exposure at each residential address was estimated by linking to the well-established high-resolution simulation dataset. Hazard ratios (HRs) were calculated using time-varying marginal structural Cox models, an established causal inference approach, after adjusting for potential confounders. During follow-up, a total of 717 subjects died from T2DM. For every 1⯵g/m3 increase in PM2.5, the adjusted HRs and 95% confidence interval (CI) for T2DM mortality was 1.036 (1.019-1.053). Similarly, for every 1⯵g/m3 increase in PM1 and PM1-2.5, the adjusted HRs and 95% CIs were 1.032 (1.003-1.062) and 1.085 (1.054-1.116), respectively. Additionally, we observed a generally more pronounced impact among individuals with lower levels of education or lower residential greenness which as measured by the Normalized Difference Vegetation Index (NDVI). We identified substantial interactions between NDVI and PM1 (P-interaction = 0.003), NDVI and PM2.5 (P-interaction = 0.019), as well as education levels and PM1 (P-interaction = 0.049). The study emphasizes the need to consider environmental and socio-economic factors in strategies to reduce T2DM mortality. We found that PM1, PM2.5, and PM1-2.5 heighten the peril of T2DM mortality, with education and green space exposure roles in modifying it.
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Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus Tipo 2 , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Prospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , China/epidemiologia , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversosRESUMO
Non-cardiac surgical procedures present a significant circulatory stress and can potentially trigger cardiovascular events, such as myocardial infarction and heart failure. Myocardial injury before non-cardiac surgery is associated with an increased risk of mortality and major cardiovascular complications during perioperative period, as well as up to 5 years after non-cardiac surgery. While the definition of preoperative myocardial injury is not yet clear, it is generally understood as myocardial injury resulting from various causes of troponin elevation without acute coronary syndrome prior to surgery. Detecting preoperative myocardial injury through routine troponin monitoring is crucial for reducing perioperative risk, but it is also challenging. The aim of this review is to discuss the definition of preoperative myocardial injury, its pathophysiology, implications on clinical practice and decision-making for patients with elevated troponin levels before non-cardiac surgery.
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BACKGROUND: Plastic surgery is a surgical specialty that focuses on restoring, reconstructing, or changing the human body. Somatic deformities (SD) are defined by a distorted impression of one's own body image and are rather frequent. The majority of people with SD have some level of social and vocational impairment, with obsessive concerns about appearance leading to compulsive behaviors and, in more severe situations, suicidal thoughts. OBJECTIVE: The current study aims to confirm the prevalence of SD in plastic surgery patients using a systematic review of the literature and a meta-analysis. METHODOLOGY: We have searched for electronic databases with MeSH terms, and the studies for analysis were selected based on inclusion and exclusion criteria and quality assessment. The study was conducted as per the PRISMA guidelines. The pooled prevalence was calculated using fixed and random effect model. The publication bias was assessed qualitatively (funnel plot) as well as quantitatively (Begg, Egger and Harbord tests). All analysis was done using Stats Direct (version 3). RESULTS: The pooled prevalence of somatic deformities in plastic surgery with 95% confidence interval using random effect model was found to be 0.19 [0.12, 0.27] which indicates a significant association of somatic deformities in plastic surgery. The heterogeneity among studies was found to be high as indicated by Cochran Q (P < 0.0001) and I2 tests (98.6%). The qualitative and quantitative analysis has also shown significant involvement of publication bias. CONCLUSION: Based on available evidence, there is a significant association of somatic deformities in plastic surgery. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Transtornos Dismórficos Corporais , Procedimentos de Cirurgia Plástica , Cirurgia Plástica , Humanos , Cirurgia Plástica/métodos , Prevalência , Imagem Corporal , Transtornos Dismórficos Corporais/cirurgiaRESUMO
BACKGROUND: Anti-inflammatory drugs are commonly used to lower inflammation which is linked to a variety of disorders. It acts by inhibiting cyclooxygenase-mediated prostaglandin synthesis at the molecular level. Hematoma is related with the use of anti-inflammatory medications. However, the specific link is still unknown. Thus, the main objective of the study is to find out the association of hematoma with ant-inflammatory drugs. MATERIAL AND METHODS: The relevant studies were searched in PubMed and screened based on inclusion and exclusion criteria. The quality of full-text studies was assessed using suitable Newcastle-Ottawa Scale. The overall estimate was calculated in terms of odds ratio with 95% confidence interval. The random effect model was used. The qualitative analysis of publication bias was done through funnel plot. RESULTS: The overall estimate measures [OR 1.01 (0.50, 2.06)] have shown non-significant risk of hematoma with use of anti-inflammatory drugs in plastic surgery as compared to non-anti-inflammatory drugs. The heterogeneity among studies was found to be 34%. The subgroup analysis of individual drugs was not done due to availability of a smaller number of studies. CONCLUSION: Based on available data, there is no significant risk of hematoma with use of anti-inflammatory drugs in plastic surgery. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Procedimentos de Cirurgia Plástica , Cirurgia Plástica , Humanos , Procedimentos de Cirurgia Plástica/efeitos adversos , Cirurgia Plástica/efeitos adversos , Cirurgia Plástica/métodos , Hematoma/induzido quimicamente , Hematoma/epidemiologia , InflamaçãoRESUMO
Proteasome 20S Subunit Beta 2 (PSMB2) has been suggested to play several roles in cancer. However, the role of PSMB2 and its underlying mechanisms in gastric cancer have not been studied. In this study, qRT-PCR was employed to detect the expression of genes that encode for 26 s proteasome subunit proteins. PSMB2 expression and its prognostic ability were assessed by collecting patient tissue samples and reviewing the TCGA and Kaplan-Meier Plotter databases. Immunofluorescence and western blotting experiments were performed to evaluate the expression of PSMB2 in human gastric cancer cells and normal gastric epithelial cells. Subsequently, PSMB2 was knocked down in HGC-27 and SNU-1 cells and overexpressed in N-87 and AGS cells. Proteasome activity assays, 5-Ethynyl-2'-deoxyuridine staining, and TUNEL assays were used to assess proteasome activity, cell proliferation, and apoptosis. Tumor xenograft assays were conducted to evaluate PSMB2 function in vivo. Our results showed that a total of 8 genes encoding for the 26 s proteasome subunit protein were highly expressed in a variety of gastric cancer cells. Next, PSMB2 was selected as the focus of subsequent studies which showed that PSMB2 was highly expressed in samples of gastric cancer tissue. Furthermore, a review of the TCGA database revealed that a high level of PSMB2 expression was associated with a poor clinical prognosis. Our results indicated that PSMB2 overexpression promoted proteasome activity, cell proliferation, and suppressed the apoptosis of gastric cancer cells, while those effects were reversed by treatment with a proteasome inhibitor (MG132). In contrast, PSMB2 knockdown produced the opposite effects and also blocked NRF1 activation. Moreover, PSMB2 knockdown inhibited tumor growth in vivo, decreased PSMB2 expression and cell proliferation, and promoted apoptosis in tumor tissues. Our findings revealed the role played by PSMB2 in gastric cancer and suggest PSMB2 as a new target molecule for use in diagnosing and treating gastric cancer.
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Background: Colorectal cancer (CRC) is a malignancy with high mortality. TSPYL2 participates in tumor suppression but its role in CRC remains unknown. Methodology & results: TSPYL2 was downregulated and SIRT1 was upregulated in gefitinib drug-resistant (GEF-DR) tissues of patients with CRC. The GEF-resistant cells, HCT116 and HCT-15, were successfully established. The knockdown of TSPYL2 promoted resistance to GEF in CRC cells. Interestingly, immunofluorescence and western blot assays demonstrated that TSPYL2 inhibited DNA damage repair in HCT-15 and HCT116 GEF-resistant cells. Mechanically, TSPYL2 reduced the resistance to GEF and inhibited DNA damage repair via suppressing SIRT1-mediated FOXO3 deacetylation. TSPYL2 consistently inhibited tumor growth and decreased resistance to GEF in vivo. Conclusion: TSPYL2 reduced resistance to GEF and suppressed DNA damage through downregulating SIRT1-mediated FOXO3 deacetylation, indicating that TSPYL2 might be a novel therapeutic target in CRC.
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Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Sirtuína 1 , Dano ao DNA , Proteína Forkhead Box O3 , Gefitinibe/farmacologia , Células HCT116 , HumanosRESUMO
ABSTRACT: The tumor microenvironment (TME) plays an important role in the development of breast cancer. Due to limitations in experimental conditions, the molecular mechanism of TME in breast cancer has not yet been elucidated. With the development of bioinformatics, the study of TME has become convenient and reliable.Gene expression and clinical feature data were downloaded from The Cancer Genome Atlas database and the Molecular Taxonomy of Breast Cancer International Consortium database. Immune scores and stromal scores were calculated using the Estimation of Stromal and Immune Cells in Malignant Tumor Tissues Using Expression Data algorithm. The interaction of genes was examined with protein-protein interaction and co-expression analysis. The function of genes was analyzed by gene ontology enrichment analysis, Kyoto Encyclopedia of Genes and Genomes analysis and gene set enrichment analysis. The clinical significance of genes was assessed with Kaplan-Meier analysis and univariate/multivariate Cox regression analysis.Our results showed that the immune scores and stromal scores of breast invasive ductal carcinoma (IDC) were significantly lower than those of invasive lobular carcinoma. The immune scores were significantly related to overall survival of breast IDC patients and both the immune and stromal scores were significantly related to clinical features of these patients. According to the level of immune/stromal scores, 179 common differentially expressed genes and 5 hub genes with prognostic value were identified. In addition, the clinical significance of the hub genes was validated with data from the molecular taxonomy of breast cancer international consortium database, and gene set enrichment analysis analysis showed that these hub genes were mainly enriched in signaling pathways of the immune system and breast cancer.We identified five immune-related hub genes with prognostic value in the TME of breast IDC, which may partly determine the prognosis of breast cancer and provide some direction for development of targeted treatments in the future.
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Biomarcadores Tumorais/genética , Neoplasias da Mama , Carcinoma Ductal , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Carcinoma Ductal/genética , Carcinoma Ductal/imunologia , Carcinoma Ductal/patologia , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Humanos , Estimativa de Kaplan-Meier , Terapia de Alvo Molecular/métodos , Invasividade Neoplásica/genética , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
Electromagnetic-interference (EMI) shielding materials that are green, lightweight, and with high mechanical properties need to be urgently developed to address increasingly severe radiation pollution. However, limited EMI shielding materials are successfully used in practical applications, due to the intensive energy consumption or the absence of sufficient strength. Herein, an environmentally friendly and effective method was proved to fabricate wood-based composites with high mechanical robustness and EMI shielding performance by a MXene/cellulose scaffold assembly strategy. The lignocellulose composites with a millimeter-thick mimic the "mortar-brick" layered structure, resulting in excellent mechanical properties that can achieve the compressive strength of 288 MPa and EMI shielding effectiveness of 39.3 dB. This "top-down" method provides an alternative for the efficient production of robust and sustainable EMI shielding materials that can be used in the fields of structural materials for next-generation communications and electronic devices.
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Celulose/química , Proteção Radiológica/instrumentação , Madeira/química , Celulose/ultraestrutura , Força Compressiva , Módulo de Elasticidade , Condutividade Elétrica , Campos Eletromagnéticos , Lignina/química , Lignina/ultraestrutura , Ciência dos Materiais , Teste de Materiais , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira/ultraestruturaRESUMO
OBJECTIVES: The aim of this study was to assess the effects of coexposure to job strain and shift work on mental health in railway workers. DESIGN: Cross-sectional study. SETTING: One Railway Bureau Group in China. PARTICIPANTS: A total of 1270 front-line railway workers. OUTCOME MEASURES: The Symptom Checklist-90-Revised questionnaire was used to measure general mental health. Job strain variables were derived from the Job Content Questionnaire. Based on the records of the work schedule 3 months prior to the survey, the following three shift types were identified: fixed day, fixed night and rotating night shifts. Risks associated with mental health were assessed by carrying out logistic regression analysis which was adjusted for age, job tenure, smoking and exercise. Additionally, a crossover analysis was employed for the combined effects. RESULTS: High levels of job strain were linked to a higher risk of poor mental health (OR=1.53, 95% CI: 1.10 to 2.11). After adjusting for confounding factors, night shifts and rotating night shifts were significant risk factors for mental health (OR=2.21, 95% CI: 1.60 to 3.07; OR=2.36, 95% CI: 1.73 to 3.22). Compared with participants who experienced a low level of job strain and day shifts, those with a high level of job strain and who worked rotating shifts were at the highest risk of poor mental health (OR=4.68, 95% CI: 2.91 to 8.04), whereas the influence of a low level of job strain and rotating night shifts was not statistically significant. CONCLUSION: Job strain and night shifts among workers were associated, both independently and in combination, with an increased risk of poor mental health. Our data suggest that job strain contributes to the risk of poor mental health by means of a combined effect with shift work.
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Saúde Mental , Jornada de Trabalho em Turnos , China/epidemiologia , Estudos Transversais , Humanos , Tolerância ao Trabalho ProgramadoRESUMO
Caloric restriction (CR) is known to extend life span across species; however, the molecular mechanisms are not well understood. We investigate the mechanism by which glucose restriction (GR) extends yeast replicative life span, by combining ribosome profiling and RNA-seq with microfluidic-based single-cell analysis. We discovered a cross-talk between glucose sensing and the regulation of intracellular methionine: GR down-regulated the transcription and translation of methionine biosynthetic enzymes and transporters, leading to a decreased intracellular methionine concentration; external supplementation of methionine cancels the life span extension by GR. Furthermore, genetic perturbations that decrease methionine synthesis/uptake extend life span. These observations suggest that intracellular methionine mediates the life span effects of various nutrient and genetic perturbations, and that the glucose-methionine cross-talk is a general mechanism for coordinating the nutrient status and the translation/growth of a cell. Our work also implicates proteasome as a downstream effector of the life span extension by GR.
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Longevidade , Metionina , Suplementos Nutricionais , Glucose/farmacologia , Saccharomyces cerevisiae/genéticaRESUMO
AIMS: Circular RNAs (circRNAs) have been emerged as novel regulators in multiple tumorigenesis, including melanoma. CircRNA_0084043 was recently demonstrated to be deregulated in human melanoma cells. Nevertheless, its role and mechanism are largely unrevealed in melanoma. MATERIALS AND METHODS: Expression of circ_0084043, miRNA (miR)-429 and tribbles homolog 2 (TRIB2) was detected using reverse transcription-quantitative PCR quantitative PCR (RT-qPCR) and western blotting. Cell proliferation, apoptosis, migration and invasion were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry and transwell assays, respectively. The activation of Wnt/ß-catenin pathway was evaluated by western blotting. The target binding among circ_0084043, miR-429 and TRIB2 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation. In vivo, mice xenograft model was generated to investigate tumor growth. KEY FINDINGS: Expression of circ_0084043 and TRIB2 was upregulated in human melanoma tissues and cell lines. Both circ_0084043 knockdown and TRIB2 silencing could decrease cell proliferation, migration and invasion, but facilitate apoptosis in A375 and SK-MEL-28 cells. Furthermore, TRIB2 restoration partially abrogated the tumor-suppressive role of circ_0084043 knockdown in melanoma cells in vitro. Then, we verified that circ_0084043 positively and physically controlled TRIB2 expression through sponging miR-429. Besides, expression of ß-catenin, c-Myc and cyclinD1 was inhibited in A375 and SK-MEL-28 cells when circ_0084043 was knocked down, accompanied with increased miR-429 and decreased TRIB2. Notably, circ_0084043 downregulation impeded tumor growth of A375 cells in vivo. SIGNIFICANCE: Knockdown of circ_0084043 suppressed the malignant development of melanoma presumably through modulating miR429/TRIB2 axis and inactivating Wnt/ß-catenin signaling pathway.
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Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Melanoma/patologia , MicroRNAs/metabolismo , RNA Circular/genética , Neoplasias Cutâneas/patologia , Via de Sinalização Wnt , beta Catenina/metabolismo , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Masculino , Melanoma/metabolismo , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Neoplasias Cutâneas/metabolismoRESUMO
Laena hongqiao sp. n. is described from Shanghai. This discovery expands the provincial distribution of the huge tenebrionid genus Laena in mainland China, and enriches the knowledge of the species diversity in Shanghai. A key modified from Schawaller 2008 and Wei Ren 2018 is provided to include this new species.
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Besouros , Distribuição Animal , Animais , ChinaRESUMO
Four pselaphine species are reported to occur in Shanghai, all belonging to the tribe Batrisini. A new species, Batriscenellus xijiaogongyuan sp. n., is described based on the material collected at the Shanghai Zoo. New distributional or collecting data for three species, i.e. Batrisodes sibiricus Sharp, Physomerinus pedator (Sharp), and Batriscenellus orientalis (Löbl), are provided.
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Besouros , Distribuição Animal , Animais , ChinaRESUMO
BACKGROUND: Catheter-based renal denervation (RDN) is a novel treatment for resistant hypertension (RH). A recent meta-analysis reported that RDN did not significantly reduce blood pressure (BP) based on the pooled effects with mild to severe heterogeneity. The aim of the present study was to identify and reduce clinical sources of heterogeneity and reassess the safety and efficacy of RDN within the identified homogeneous subpopulations. METHODS: This was a meta-analysis of 9 randomized clinical trials (RCTs) among patients with RH up to June 2016. Sensitivity analyses and subgroup analyses were extensively conducted by baseline systolic blood pressure (SBP) level, antihypertensive medication change rates, and coronary heart disease (CHD). RESULTS: In all patients with RH, no statistical differences were found in mortality, severe cardiovascular events rate, and changes in 24-h SBP and office SBP at 6 and 12 months. However, subgroup analyses showed significant differences between the RDN and control groups. In the subpopulations with baseline 24-h SBP ≥155 mmHg (1 mmHg = 0.133 kPa) and the infrequently changed medication, the use of RDN resulted in a significant reduction in 24-h SBP level at 6 months (P = 0.100 and P= 0.009, respectively). Subgrouping RCTs with a higher prevalent CHD in control showed that the control treatment was significantly better than RDN in office SBP reduction at 6 months (P < 0.001). CONCLUSIONS: In all patients with RH, the catheter-based RDN is not more effective in lowering ambulatory or office BP than an optimized antihypertensive drug treatment at 6 and 12 months. However, among RH patients with higher baseline SBP, RDN might be more effective in reducing SBP.
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Hipertensão/cirurgia , Rim/cirurgia , Simpatectomia/métodos , Feminino , Humanos , Hipertensão/fisiopatologia , Rim/patologia , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Artéria Renal/patologia , Artéria Renal/cirurgiaRESUMO
A new species, Onryza pesudomaga is described from Zhejiang Province, S. China. The new taxon resembles O. maga which is widely distributed in S. China and Taiwan. Differences and some biological information of the two allied species are given. A key to species of the genus Onryza Watson, 1893 and a distribution map of all the members of this genus are provided.
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Lepidópteros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , China , Feminino , Lepidópteros/anatomia & histologia , Lepidópteros/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , TaiwanRESUMO
Au-Pt core-shell nanoparticles have been synthesized on a reduced graphene oxide (RGO) surface by an under-potential deposition (UPD) redox replacement technique, which involves redox replacement of a copper UPD monolayer by PtCl4²â» that could be reduced and deposited simultaneously. Scanning electron microscopy (SEM) and electrochemical methods have been used to characterize the graphene decorated with Au-Pt core-shell nanoparticles. The electrochemical experiments show that the materials exhibit excellent catalytic activity towards the oxygen reduction reaction and the methanol oxidation reaction. It is believed that the high-performance of this new catalyst is due to the ultrathin Pt shell on the Au nanoparticles surface and the oxygen-containing functional groups on the RGO surface.
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Ultralow Pt-loading Au nanoflowers (AuNFs) were synthesized on a glassy carbon electrode surface by the underpotential deposition (UPD) monolayer redox replacement technique, which involves redox replacement of a copper UPD monolayer by PtCl(4)(2-) that can be reduced and deposited simultaneously. Field-emission scanning electron microscopy, energy dispersive spectroscopy, x-ray photoelectron spectroscopy and the electrochemical method were utilized to characterize the ultralow Pt-loading AuNFs. Cyclic voltammogram results showed that the ultralow Pt-loading AuNFs exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide and the oxidation of glucose in neutral media, and the reaction pathway of glucose oxidation was changed from an intermediate process based on the electrosorption of glucose to a direct oxidation process. From chronoamperometric results, it could be obtained that this prepared biosensor had wide linear ranges and very low detection limits (DLs) for H(2)O(2) (0.025-94.3 µM; DL = 0.006 µM) and glucose (0.0028-8.0 mM; DL = 0.8 µM), which were much better than previous results.
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Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , Glucose/química , Peróxido de Hidrogênio/análise , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microquímica/instrumentação , Platina/química , Cristalização/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Glucose/análise , Peróxido de Hidrogênio/química , Tamanho da PartículaRESUMO
The Slit-Robo GTPase-activating proteins (srGAPs) play an important role in neurite outgrowth and axon guidance; however, little is known about its role in nerve regeneration after injury. Here, we studied the expression of srGAPs in mouse dorsal root ganglia (DRG) following sciatic nerve transection (SNT) using morphometric and immunohistochemical techniques. Reverse transcriptase polymerase chain reaction and Western blot analysis indicated that srGAP1 and srGAP3, but not srGAP2, were expressed in normal adult DRG. Following unilateral SNT, elevated mRNA and protein levels of srGAP1 and srGAP3 were detected in the ipsilateral relative to contralateral L(3-4) DRGs from day 3 to day 14. Immunohistochemical results showed that srGAP1 and srGAP3 were largely expressed in subpopulations of DRG neurons in naïve DRGs. However, after SNT, srGAP3 in neurons was significantly increased in the ipsilateral relative to contralateral DRGs, which peaked at day 7 to day 14. Interestingly, DRG neurons with strong srGAP3 labeling also coexpressed Robo2 after peripheral nerve injury. These results suggest that srGAPs are differentially expressed in murine DRG and srGAP3 are the predominant form. Moreover, srGAP3 may participate in Slit-Robo signaling in response to peripheral nerve injury or the course of nerve regeneration.