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1.
J Immunol ; 210(12): 2001-2015, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37154707

RESUMO

Abundant evidence demonstrates that mechanical stress could induce an inflammatory response in periodontal tissue, but the precise mechanism remains unclear. In the past few years, periodontal ligament cells (PDLCs), as the most force-sensitive cells, have been investigated in depth as local immune cells, associated with activation of inflammasomes and secretion of inflammatory cytokines in response to mechanical stimuli. However, this study innovatively inspected the effect of PDLCs on the other immune cells after stretch loading to reveal the detailed mechanism by which mechanical stimuli initiate immunoreaction in periodontium. In the present study, we found that cyclic stretch could stimulate human PDLCs to secret exosomes and that these exosomes could further induce the increase of phagocytic cells in the periodontium in Sprague-Dawley rats and the M1 polarization of the cultured macrophages (including the mouse macrophage cell line RAW264.7 and the bone marrow-derived macrophages from C57BL/6 mice). Furthermore, the exosomal miR-9-5p was detected to be overexpressed after mechanical stimuli in both in vivo and in vitro experiments and could trigger M1 polarization via the SIRT1/NF-κB signaling pathway in the cultured macrophages. In summary, this study revealed that PDLCs could transmit the mechanobiological signals to immune cells by releasing exosomes and simultaneously enhance periodontal inflammation through the miR-9-5p/SIRT1/NF-κB pathway. We hope that our research can improve understanding of force-related periodontal inflammatory diseases and lead to new targets for treatment.

2.
Indian J Microbiol ; 64(1): 82-91, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468732

RESUMO

Children obesity is a serious public health problem drawing much attention around the world. Recent research indicated that gut microbiota plays a vital role in children obesity, and disturbed gut microbiota is a prominent characteristic of obese children. Diet and exercise are efficient intervention for weight loss in obesity children, however, how the gut microbiota is modulated which remains largely unknown. To characterize the feature of gut microbiota in obese children and explore the effect of dietary and exercise on gut microbiota in simple obese children, 107 healthy children and 86 obese children were recruited, and among of the obese children 39 received the dietary-exercise combined weight loss intervention (DEI). The gut microbiota composition was detected by the 16S amplicon sequencing method. The gut microbiota composition was significantly different between obese children and the healthy cohort, and DEI significantly reduced the body weight and ameliorated the gut microbiota dysbiosis. After DEI, the abundance of the Akkermansia muciniphila was increased, while the abundance of the Sutterella genus was decreased in simple obese children. Our results may provide theoretical reference for future personalized obesity interventions based on gut microbiota. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01088-3.

3.
J Oral Pathol Med ; 52(10): 951-960, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37828627

RESUMO

BACKGROUND: Oral squamous cell carcinoma is an increasingly prevalent cancer type characterized by high incidence and mortality rates. Its early detection is challenging, primarily because of the absence of early molecular markers. Cuproptosis is a novel regulatory mechanism of cell death with implications in various cancers. In this study, we aimed to study cuproptosis-related genes in oral squamous cell carcinoma to identify their prognostic value. METHODS: By analyzing genomic, bulk RNA-seq, and single-cell RNA-seq data, we investigated 13 cuproptosis-related genes in The Cancer Genome Atlas-Oral Squamous Cell Carcinoma dataset and Gene Expression Omnibus repository (GSE172577). RESULTS: ATP7A, ATP7B, and DLST were the most frequently mutated genes, with nine of our studied genes associated with overall survival. Single-cell analysis was conducted to identify cuproptosis-related tumor cells in oral squamous cell carcinoma, which revealed two distinct patterns based on the expression of cuproptosis-related genes. These patterns exhibit differences in genetic alterations and tumor immune microenvironment. Finally, we developed a cuproptosis index using a random forest algorithm based on cuproptosis pattern-related genes in which higher levels were linked to poorer prognosis. CONCLUSION: Our findings provide valuable insights into the mechanisms underlying oral squamous cell carcinoma-associated cuproptosis.


Assuntos
Apoptose , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/genética , Morte Celular , Neoplasias Bucais/genética , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Microambiente Tumoral/genética , Cobre
4.
Environ Res ; 231(Pt 3): 116211, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257739

RESUMO

Among infectious diseases, pneumonia is the greatest cause of mortality in children less than 5 years old. Approximately 27% of Beijing's 3-8 year-old children have had pneumonia at least once. The sole reservoir of pneumonia pathogens is the human nasopharynx. We investigated associations and interactions among two kinds of environmental risk factors: i) airborne pathogens, namely closed bedroom window and shared bedroom and ii) pollutants, namely traffic pollution and environmental tobacco smoke (ETS). We evaluated breastfeeding's (BF) protective value against childhood pneumonia. The database consists of responses to a questionnaire in a cross-sectional study. Crude and adjusted Odds Ratios were assessed independently for each risk factor. Combinations of the studied risk factors were analyzed using multivariate logistic regression. Risk factors were evaluated for interactions on the additive scale using the metrics Relative Excess Risk due to Interaction (RERI), Attributable Proportion (AP) and Synergy Index (S). All independent risk factors were significant for children's pneumonia. We also found evidence of possible synergistic interaction between pairs of risk factors that was stronger when one of the risk factors was a closed bedroom window. Remarkably, window opening was associated with reduced risk of pneumonia for children living near heavy traffic pollution. Longer duration BF was more protective than shorter, and exclusive BF was more protective than partial BF against childhood pneumonia. In conclusion, low ventilation (closed bedroom windows), shared bedroom, ETS, and traffic exposure were associated with increased risk of pneumonia. Exclusive BF for more than six months had the greatest protective value against pneumonia.


Assuntos
Poluentes Atmosféricos , Pneumonia , Poluição por Fumaça de Tabaco , Humanos , Criança , Pré-Escolar , Pequim/epidemiologia , Estudos Transversais , Fatores de Risco , Poluição por Fumaça de Tabaco/efeitos adversos , Pneumonia/induzido quimicamente , Pneumonia/epidemiologia , Demografia , Exposição Ambiental/análise
5.
Acta Radiol ; 64(2): 542-551, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35300519

RESUMO

BACKGROUND: A high false-positive rate remains a technical glitch hindering the broad spectrum of application of deep-learning-based diagnostic tools in routine radiological practice from assisting in diagnosing rib fractures. PURPOSE: To examine the performance of two versions of deep-learning-based software tools in aiding radiologists in diagnosing rib fractures on chest computed tomography (CT) images. MATERIAL AND METHODS: In total, 123 patients (708 rib fractures) were included in this retrospective study. Two groups of radiologists with different experience levels retrospectively reviewed images for rib fractures in the concurrent mode aided with RibFrac-High Sensitivity (HS) and RibFrac-High Precision (HP). We compared their diagnostic performance against the reference standard in terms of sensitivity and positive predictive value (PPV). RESULTS: On a per-patient basis, RibFrac-HS exhibited a higher sensitivity compared with RibFrac-HP (mean difference=0.051, 95% CI=0.012-0.090; P = 0.011), whereas the latter significantly outperformed the former in terms of the PPV (mean difference=0.273, 95% CI=0.238-0.308; P < 0.0001). The use of RibFrac-HP significantly improved the junior and the senior groups' sensitivities respectively by 0.058 (95% CI=0.033-0.083; P < 0.0001) and 0.058 (95% CI=0.034-0.081; P < 0.0001), and decreased the diagnosis time by 206 s (95% CI=191-220; P < 0.0001) and 79 s (95% CI=67-92; P < 0.0001), respectively, when compared to no software assistance. CONCLUSION: The sensitivity and efficiency of radiologists in identifying rib fractures can be improved by using RibFrac-HS and/or RibFrac-HP. With an added module for false-positive suppression, RibFrac-HP maintains the sensitivity and increases the PPV in fracture detection compared to Rib-Frac-HS.


Assuntos
Aprendizado Profundo , Fraturas das Costelas , Humanos , Fraturas das Costelas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Tórax , Sensibilidade e Especificidade
6.
Exp Cell Res ; 400(2): 112505, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33516666

RESUMO

Inflammation and alveolar bone destruction constitute the main pathological process of periodontitis. However, the molecular mechanisms of bone destruction under the inflammation environment remain unclear. This study aims to explore the role of Ephrin-B2/EphB4 signaling in osteogenic differentiation under the inflammation environment. Mouse pre-osteoblasts MC3T3-E1 were pretreated with lipopolysaccharide of Porphyromonas gingivalis (Pg-LPS). The Ephrin-B2/EphB4 signaling was activated, and the osteogenic differentiation of cells was examined. The results showed that activation of Ephrin-B2/EphB4 signaling promoted the expression levels of osteogenic differentiation-related genes, and also relieved the inhibitory effect of Pg-LPS on osteogenesis. Noticeably, the effect of Ephrin-B2/EphB4 signaling might be related to the mitogen-activated protein kinase (MAPK) pathway. While applying Ephrin-B2-Fc and EphB4-Fc to periodontitis mice, we observed the reduction of alveolar crest destruction. The current study revealed the possible role of Ephrin-B2/EphB4 signaling in reducing bone destruction in periodontitis and suggested its potential values for further research.


Assuntos
Efrina-B2/metabolismo , Fragmentos Fc das Imunoglobulinas/imunologia , Inflamação/prevenção & controle , Osteoblastos/citologia , Osteogênese , Periodontite/prevenção & controle , Receptor EphB4/metabolismo , Animais , Diferenciação Celular , Efrina-B2/genética , Efrina-B2/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/imunologia , Osteoblastos/metabolismo , Periodontite/imunologia , Periodontite/metabolismo , Receptor EphB4/genética , Receptor EphB4/imunologia , Transdução de Sinais
7.
Psychol Health Med ; 27(1): 265-279, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33573426

RESUMO

The prevalence of and risk factors for uncertainty stress among residents during the COVID-19 pandemic remain unclear. An online cross-sectional survey was conducted to explore and identify the risk factors for high perceived uncertainty stress among the general public in China during the COVID-19 outbreak. Information about the respondents' socioeconomic characteristics, knowledge of and attitudes towards COVID-19, perceived uncertainty stress, social capital, anxiety, and depressive symptoms was collected and analysed. Among the 1205 respondents, 45.3% (546) reported a high level of uncertainty stress. Multiple linear regression analysis indicated that anxiety (ß=3.871,P<0.001) and depression symptoms (ß=2.458, P<0.001), family residence (in towns or rural areas) (ß=0.947, P<0.001), lack of support for local epidemic control strategies (ß=1.253, P<0.001), worry about the pandemic (ß=1.191, P<0.001), and symptoms of weakness among family members (ß=1.525, P=0.002) were positively associated with perceived uncertainty stress. Cognitive social capital (ß=-0.883, P<0.001) and social networks (ß=-0.726, P<0.001) were negatively, but social participation (ß=0.714, P<0.001) was positively associated with perceived uncertainty stress. Our findings identify factors associated with a higher level of uncertainty stress and should be helpful in the consideration of effective policies and interventions for uncertainty stress during the initial phases of public health emergencies.


Assuntos
COVID-19 , Pandemias , Ansiedade/epidemiologia , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos , SARS-CoV-2 , Inquéritos e Questionários , Incerteza
8.
J Prosthet Dent ; 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35249741

RESUMO

STATEMENT OF PROBLEM: Whether fiber-reinforced composite (FRC) posts should be inserted in root canals to restore teeth with multiple roots remains unclear. PURPOSE: The purpose of this finite element analysis (FEA) study was to determine the optimal use of FRC posts in an endodontically treated maxillary first molar with a 4-wall defect and 1.5-mm-high ferrule. MATERIAL AND METHODS: Eight different models of a maxillary first molar were established: no post (NP), post in palatal root (P), post in distobuccal root (DB), post in mesiobuccal root (MB), posts in palatal root and distobuccal root (P+DB), posts in palatal root and mesiobuccal root (P+MB), posts in 2 buccal roots (DB+MB), and posts in all roots (P+DB+MB). Two types of loading were applied: a force of 800 N parallel to the long axis of the tooth to simulate the vertical masticatory force and another force of 225 N at 45 degrees to the long axis of the tooth to simulate the lateral masticatory force. The equivalent stresses on the external surfaces of the tooth tissue, the internal surfaces of the root canals and in the posts, as well as the maximal shear stresses on the post-core interface and the core-dentin interface, were calculated with FEA. RESULTS: All the models showed similar maximal equivalent stress values on the external surfaces of the tooth tissue, and stress concentrations were found at the cervical and furcation area. On the internal surfaces of root canals, an increase of equivalent stress at the middle third of the canals with posts and a decrease at the cervical third were observed. Under vertical loading, the P+DB+MB group showed the largest equivalent stress in the post (76.45 MPa in the palatal post), the DB+MB group showed the largest shear stress on the post-core interface (19.02 MPa), and the MB group showed the largest shear stress on the core-dentin interface (12.07 MPa). Under lateral loading, the P+DB+MB group showed the largest equivalent stress in the post (60.11 MPa in the mesiobuccal post) and the largest shear stress on the post-core interface (13.48 MPa) and the DB group showed the largest shear stress on the core-dentin interface (21.03 MPa). CONCLUSIONS: One post in the palatal canal was found to be appropriate for the FRC post and resin core restoration of a maxillary first molar with a 4-wall defect and 1.5-mm-high ferrule. An additional post in the mesiobuccal canal could help disperse lateral occlusal force and improve retention of the restoration.

9.
Psychogeriatrics ; 22(2): 243-251, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35048467

RESUMO

BACKGROUND: Numerous studies have confirmed that the apolipoprotein E4 allele (APOE4) gene and arteriosclerosis (AS) have a combined effect on the occurrence of cognitive function impairment, and dyslipidaemia levels are significantly correlated with APOE4 levels and AS. Few studies have focused on the combined effect of the APOE4 gene and AS on cognitive function. Therefore, this study aimed to investigate the effect of APOE4 gene and AS acting together on cognitive function through dyslipidaemia levels, which could provide certain scientific research value for future studies. METHODS: A multi-stage cluster sampling method was used to investigate older adults aged 60 years and above in rural areas of Guizhou, China. The demographic sociological characteristics were collected, and laboratory tests, blood lipid measurements, and physical examinations were performed. Mini-Mental State Examination (MMSE) was used to determine cognitive function. Analysis of variance with two-factor factorial design was used to analyse the interaction between the APOE4 gene and AS on cognitive function and its domains. RESULTS: A total of 549 elderly subjects were eligible for this study. The result of the factorial design analysis revealed there was a significant interaction between the APOE4 gene and AS in terms of attention and numeracy (F = 6.878, P = 0.009). CONCLUSIONS: The combination of the APOE4 gene and AS leads to a decrease in the level of attention and numeracy domains, and certain attention should be focused on such populations in the future.


Assuntos
Arteriosclerose , Disfunção Cognitiva , Idoso , Apolipoproteína E4/genética , China , Disfunção Cognitiva/genética , Estudos Transversais , Humanos
10.
J Esthet Restor Dent ; 33(4): 560-566, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33682306

RESUMO

OBJECTIVE: This article introduced a modified method to fabricate an individualized abutment-crown integrated provisional restoration for single-tooth implant restoration in the esthetic zone, which created a satisfactory peri-implant soft tissue architecture. CLINICAL CONSIDERATIONS: Three months after the implant placement, the individualized abutment-crown integrated provisional restoration was designed and fabricated in the laboratory, by referring to the profile of natural contra-lateral tooth digitally, and seated on the implant afterwards. The peri-implant soft tissue architecture was evaluated and the Pink Esthetic Score (PES) was recorded. The provisional restoration stayed on the implant for 3 months until the individualized definitive ceramic abutment and crown were fixed on the implant. CONCLUSIONS: This protocol provided an alternative solution for shaping the peri-implant soft tissue morphology in the esthetic zone by using an individualized abutment-crown integrated provisional restoration and showed promising effect on the esthetics of anterior single-tooth implant restoration. CLINICAL SIGNIFICANCE: The individualized abutment-crown integrated provisional restoration whose emergence profile mirroring that of the natural contra-lateral tooth, was designed with the help of computer-aided design-manufacture (CAD/CAM). It may help shaping the peri-implant soft tissue in the esthetic zone with merits of saving amount of hand labor of technicians as well as clinicians, and reducing the visits of patients.


Assuntos
Implantes Dentários para Um Único Dente , Implantes Dentários , Desenho Assistido por Computador , Coroas , Estética Dentária , Humanos
11.
J Muscle Res Cell Motil ; 40(3-4): 379-387, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31520264

RESUMO

Interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) are well-known cytokines with pro-inflammatory capabilities, and have been shown to be involved in adaptation to exercise as multifaceted myokines. However, the precise role of IL-6 and TNF-α during exercise-induced skeletal muscle injury and subsequent repair processes is not fully understood. In this study, IL-6 and TNF-α were examined in soleus muscles at the gene and protein levels using in situ hybridization and immunohistochemical staining, respectively, and serum levels of IL-6 and TNF-α were determined before and after a 90-min downhill running session in rats. There were no changes in serum levels of IL-6 and TNF-α after exercise, but IL-6 and TNF-α mRNA increased and maintained high expression in muscles for 1-2 weeks after exercise. IL-6 and TNF-a mRNAs were identified in both the cytoplasm and the nuclei of myocytes, as well as in invading inflammatory cells. IL-6 and TNF-α protein mainly distributed in cytoplasm unevenly and had a prolonged expression until 2 weeks after eccentric exercise. Our results demonstrate that there is increased IL-6 and TNF-α expression in skeletal muscle that is induced by eccentric exercise and that the high expression of IL-6 and TNF-α in the long-term phase after eccentric exercise may be more involved in the subsequent recovery of damaged muscle.


Assuntos
Interleucina-6/metabolismo , Músculo Esquelético/fisiologia , Condicionamento Físico Animal/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Masculino , Ratos
12.
Indoor Air ; 29(2): 202-214, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30597644

RESUMO

From October 2010 to April 2012, we conducted a cross-sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here, we analyze associations of early household renovation with preterm birth (PTB), low birthweight (LBW), term low birthweight (Term-LBW), and small for gestational age (SGA). Parents responded to questions about household renovation and their children's gestational age and birthweight. In the multivariate logistic regression analyses, household renovation in the year before pregnancy was significantly associated with LBW (sample size: N = 25 813; adjusted odds ratio (OR) with 95% confidence intervals (CIs): 1.23, 1.01-1.50) and Term-LBW (N = 24 823; 1.29, 1.01-1.67). Household renovation during pregnancy was significantly associated with PTB (N = 25 202; 1.28, 1.01-1.69). These significant associations were also found in the two-level (city-child) logistic regression analyses and in the sensitivity analyses among 21 009 children with complete data in all studied variates. Stronger associations were found in certain subgroups. Our findings indicate that household renovation within one year before pregnancy might be a risk factor for LBW and Term-LBW, while household renovation during pregnancy could be a risk factor for PTB.


Assuntos
Materiais de Construção/efeitos adversos , Recém-Nascido de Baixo Peso , Nascimento Prematuro/etiologia , Adulto , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Habitação , Humanos , Recém-Nascido Pequeno para a Idade Gestacional , Modelos Logísticos , Masculino , Gravidez , Nascimento Prematuro/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
13.
J Prosthet Dent ; 121(1): 32-36, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30006221

RESUMO

An appliance was designed and fabricated by using computer-aided design and computer-aided manufacturing (CAD-CAM) and 3-dimensional (3D) printing to combine a custom tray with an intraoral Gothic arch. This helped simplify centric relation recording and combined definitive impression making and centric relation recording into a single step.


Assuntos
Desenho Assistido por Computador , Técnica de Moldagem Odontológica/instrumentação , Planejamento de Dentadura/métodos , Prótese Total , Registro da Relação Maxilomandibular/métodos , Impressão Tridimensional , Relação Central , Materiais para Moldagem Odontológica , Humanos , Arcada Edêntula , Mandíbula , Maxila , Modelos Dentários , Boca Edêntula
14.
Mol Biol Rep ; 45(6): 1681-1689, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30168098

RESUMO

A novel feather-degrading bacterium named CA-1 was isolated from the gut of the spider Chilobrachys guangxiensis, which degrades native whole chicken feathers within 20 h. The CA-1 was confirmed to belong to Stenotrophomonas maltophilia based on morphologic and molecular analysis. Maximum feather degradation activity of the bacterium was observed at 37 °C in basal feather medium (NaCl 0.5 g/L, KH2PO4 0.3 g/L, K2HPO4 0.4 g/L, feather powder 10.0 g/L, pH 8.0), which was inhibited when glucose and ammonium nitrate were added in the medium. Furthermore, the purified enzymes under the optimal and suppressive conditions were analyzed respectively by SDS-PAGE and LC-MS/MS. Three enzymes, namely alkaline serine protease (29.1 kDa), ABC transporter permease (27.5 kDa), and alkaline phosphatase (40.8 kDa), were isolated and identified from the supernatant of the optimal culture and were considered to play principal roles. On the other hand, the potential synergic effects of the three proteins in S. maltophilia CA-1 feather degradation system were analyzed theoretically. CA-1 may product outer-membrane vesicles comprised of membranes and periplasmic proteins in the feather medium. The newly identified CA-1 and its synergic enzymes provide a new insight into further understanding the molecular mechanism of feather degradation by microbes. They also have potential application in cost-effectively degrading feathers into feeds and fertilizers through careful optimization and engineering of the three newly identified enzymes.


Assuntos
Plumas/enzimologia , Stenotrophomonas maltophilia/enzimologia , Stenotrophomonas maltophilia/metabolismo , Transportadores de Cassetes de Ligação de ATP/isolamento & purificação , Transportadores de Cassetes de Ligação de ATP/metabolismo , Fosfatase Alcalina/isolamento & purificação , Fosfatase Alcalina/metabolismo , Animais , Bactérias/metabolismo , Meios de Cultura , Plumas/microbiologia , Queratinas/metabolismo , Proteínas de Membrana Transportadoras/isolamento & purificação , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Proteólise , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/metabolismo , Aranhas/microbiologia , Stenotrophomonas maltophilia/isolamento & purificação , Especificidade por Substrato
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 593-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27209775

RESUMO

In the near-infrared spectroscopy, the Forward Interval Partial Least Squares (FiPLS) and Backward Interval Partial Least Squares (BiPLS) are commonly used modeling methods, which are based on the wavelength variable selection. These methods are usually of high prediction accuracy, but are strongly characteristic of greedy search, which causes that the intervals selected are not good enough to indicate the analyte information. To solve the problem, a spectral characteristic intervals selection strategy (FB-iPLS) based on the combination of FiPLS and BiPLS is proposed. On the basis of spectral segmentation, both FiPLSs are used to select useful intervals, and BiPLS is used to delete useless intervals, so as to perform the selection and deletion of the characteristic variables alternatively, which conducts a two-way choice of the target characteristic variables, and is used to improve the robustness of the model. The experiments on determining the ethanol concentration in pure water are conducted by modeling with FiPLS, BiPLS and the proposed method. Since different size of intervals will affect the result of the model, the experiments here will also examine the model results with different intervals of these three models. When the spectrum is divided into 60 segments, the FB-iPLS method obtains the best prediction performance. The correlation coefficients (r) of the calibration set and validation set are 0.967 7 and 0.967 0 respectively, and the cross-validation root mean square errors (RMSECV) are 0.088 8 and 0.057 1, respectively. Compared with FiPLS and BiPLS, the overall prediction performance of the proposed model is better. The experiments show that the proposed method can further improve the predictive performance of the model by resolving the greedy search feature against BiPLS and FiPLS, which is more efficient for and representative of the selection of characteristic intervals.

16.
Environ Toxicol ; 29(2): 226-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22331617

RESUMO

Exposure to ambient airborne particulate matter (PM) with an aerodynamic diameter less than 10 µm (PM10 ) links with public health hazards and increases risk for lung cancer and other diseases. Recent studies have suggested that oxidative stress is a key mechanism underlying the toxic effects of exposure to PM10 . Several components of water-soluble fraction of PM10 (sPM10 ) have been known to be capable of inducing oxidative stress in in vitro studies. In this study, we investigated if water-insoluble fraction of PM10 (iPM10 ) could be also capable of inducing oxidative stress and oxidative damage. Human lung epithelial A549 cells were exposed to 10 µg/mL of sPM10 , iPM10 or total PM10 (tPM10 ) preparation for 24 h. Here, we observed that all three PM10 preparations reduced cell viability and induced apoptotic cell death in A549 cells. We further found that, similar to the exposure to sPM10 and tPM10 , the intracellular level of hydrogen peroxide (H2 O2 ) in the iPM10 -exposed cells was increased significantly; meanwhile the activity of catalase was decreased significantly as compared with the unexposed control cells, resulting in significant DNA damage. Our data obtained from inductively coupled plasma-mass spectrometry (ICP-MS) assays showed that iron is the most abundant metal in all three PM10 preparations. Thus, we have demonstrated that, similar to sPM10 , iPM10 is also capable of inducing oxidative stress by probably inducing generation of H2 O2 and impairing enzymatic antioxidant defense, resulting in oxidative DNA damage and even apoptotic cell death through the iron-catalyzed Fenton reaction.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Poluentes Atmosféricos/química , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Pulmão/citologia , Metais Pesados/análise , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/química , Solubilidade , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Água/química
17.
Front Plant Sci ; 15: 1369696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952847

RESUMO

Effectively monitoring pest-infested areas by computer vision is essential in precision agriculture in order to minimize yield losses and create early scientific preventative solutions. However, the scale variation, complex background, and dense distribution of pests bring challenges to accurate detection when utilizing vision technology. Simultaneously, supervised learning-based object detection heavily depends on abundant labeled data, which poses practical difficulties. To overcome these obstacles, in this paper, we put forward innovative semi-supervised pest detection, PestTeacher. The framework effectively mitigates the issues of confirmation bias and instability among detection results across different iterations. To address the issue of leakage caused by the weak features of pests, we propose the Spatial-aware Multi-Resolution Feature Extraction (SMFE) module. Furthermore, we introduce a Region Proposal Network (RPN) module with a cascading architecture. This module is specifically designed to generate higher-quality anchors, which are crucial for accurate object detection. We evaluated the performance of our method on two datasets: the corn borer dataset and the Pest24 dataset. The corn borer dataset encompasses data from various corn growth cycles, while the Pest24 dataset is a large-scale, multi-pest image dataset consisting of 24 classes and 25k images. Experimental results demonstrate that the enhanced model achieves approximately 80% effectiveness with only 20% of the training set supervised in both the corn borer dataset and Pest24 dataset. Compared to the baseline model SoftTeacher, our model improves mAP @0.5 (mean Average Precision) at 7.3 compared to that of SoftTeacher at 4.6. This method offers theoretical research and technical references for automated pest identification and management.

18.
Heliyon ; 10(11): e32027, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38868037

RESUMO

Objective: Understanding the characteristics of alveolar bone resorption in an East Asian population after maxillary incisor extraction and providing a reference for implant treatment plans. Study design: Cone-beam computerized tomography (CBCT) data of 125 East Asian patients with unilateral extraction of maxillary incisors for 3 months were collected. The alveolar bone width and height in the extraction sites were measured and compared with the corresponding contralateral sites. Results: The differences in alveolar bone width between the extraction site and contralateral site were as follows: 4.11 mm, 2.68 mm, and 2.09 mm (3 mm, 5 mm, 7 mm apical from CEJ of the contralateral tooth). Data are expressed as the median. The horizontal resorption ratio of alveolar bone was 49.94 %, 31.5 %, and 24.46 %. The difference in alveolar bone height was 0.78 mm. The vertical resorption ratio was 7.78 %. The resorption did not differ significantly between sexes and was not significantly affected by tooth positions. Conclusions: In the studied East Asian population, significant horizontal and vertical alveolar bone resorption occurs after natural healing of maxillary incisor extraction for 3 months. The closer to the alveolar ridge crest, the more significant the horizontal resorption, resulting in an "inverted triangle" shape residual alveolar bone.

19.
Bioresour Technol ; 402: 130787, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703955

RESUMO

Slow dissolution/hydrolysis of insoluble/macromolecular organics and poor sludge filterability restrict the application potential of anaerobic membrane bioreactor (AnMBR). Bubble-free membrane microaeration was firstly proposed to overcome these obstacles in this study. The batch anaerobic digestion tests feeding insoluble starch and soluble peptone with and without microaeration showed that microaeration led to a 65.7-144.8% increase in methane production and increased critical flux of microfiltration membrane via driving the formation of large sludge flocs and the resultant improvement of sludge settleability. The metagenomic and bioinformatic analyses showed that microaeration significantly enriched the functional genes and bacteria for polysaccharide and protein hydrolysis, microaeration showed little negative effects on the functional genes involved in anaerobic metabolisms, and substrate transfer from starch to peptone significantly affected the functional genes and microbial community. This study demonstrates the dual synergism of microaeration to enhance the dissolution/hydrolysis/acidification of insoluble/macromolecular organics and sludge filterability for AnMBR application.


Assuntos
Reatores Biológicos , Filtração , Membranas Artificiais , Esgotos , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Anaerobiose , Filtração/métodos , Metano/metabolismo , Hidrólise , Amido/metabolismo
20.
Stress ; 16(5): 557-63, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23574036

RESUMO

Restraint stress modulates pain and inflammation. The present study was designed to evaluate the effect of acute restraint stress on inflammatory pain induced by subcutaneous injection of bee venom (BV). First, we investigated the effect of 1 h restraint on the spontaneous paw-flinching reflex (SPFR), decrease in paw withdrawal mechanical threshold (PWMT) and increase in paw volume (PV) of the injected paw induced by BV. SPFR was measured immediately after BV injection, and PWMT and PV were measured 2 h before BV and 2-8 h after BV. The results showed that acute restraint inhibited significantly the SPFR but failed to affect mechanical hyperalgesia. In contrast, stress enhanced significantly inflammatory swelling of the injected paw. In a second series of experiments, the effects of pretreatment with capsaicin locally applied to the sciatic nerve, systemic 6-hydroxydopamine (6-OHDA), and systemic naloxone were examined on the antinociception and proinflammation produced by acute restraint stress. Local capsaicin pretreatment inhibited BV-induced nociception and inflammatory edema, and had additive effects with stress on nociception but reduced stress enhancement of edema. Systemic 6-OHDA treatment attenuated the proinflammatory effect of stress, but did not affect the antinociceptive effect. Systemic naloxone pretreatment eliminated the antinociceptive effect of stress, but did not affect proinflammation. Taken together, our data indicate that acute restraint stress contributes to antinociception via activating an endogenous opioid system, while sympathetic postganglionic fibers may contribute to enhanced inflammation in the BV pain model.


Assuntos
Venenos de Abelha/efeitos adversos , Hiperalgesia/etiologia , Inflamação/patologia , Nociceptividade/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Capsaicina/administração & dosagem , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/patologia , Membro Posterior/efeitos dos fármacos , Hiperalgesia/patologia , Inflamação/induzido quimicamente , Masculino , Naloxona/uso terapêutico , Oxidopamina/uso terapêutico , Dor/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Restrição Física , Nervo Isquiático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiologia
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