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1.
J Magn Reson Imaging ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847618

RESUMO

BACKGROUND: Whether fetal cardiothoracic ratio (CTR) is constant or increasing with gestational age (GA) is controversial. The majority of the fetal CTR data has been obtained through ultrasound. PURPOSE: To retrospectively analyze CTR of diameter, area, and circumference on prenatal MR images in a low-risk population of singleton pregnancies, and to clarify its diagnostic value. STUDY TYPE: Retrospective. SUBJECTS: 1024 low-risk singleton pregnancies undergoing MRI. FIELD STRENGTH: Balanced steady state free precession sequence and single shot-fast spin echo sequence at 1.5 Tesla. ASSESSMENT: Pregnancy clinical data were recorded and diameter, area, and circumference of the fetal heart and thorax were measured by two researchers with 6 and 7 years of radiology experience, respectively, and their variation with GA was investigated. The relationship between CTRs with GA was also investigated. Finally, the value of CTR in the diagnosis of fetuses with abnormal development was explored by using receiver operating characteristic (ROC) curves. STATISTICAL TESTS: Linear regression and ROC curves. A P value <0.05 was considered significant. RESULTS: There were significant positive linear correlations (R2 > 0.7, P < 0.0001) between the diameter, area, and circumference of the heart and thorax with GA. The CTRs remain constant values and do not change with GA. The 5th, 50th, and 95th percentiles of the CTR in 21-38 weeks GA were 0.32, 0.39, and 0.48 respectively. The corresponding percentiles for the area ratio were 0.15, 0.21 and 0.27, respectively, and for the circumference ratio were 0.40, 0.46, and 0.52, respectively. Based on ROC curves of CTR with three methods, the area under curves (AUCs) were up to 0.95, the sensitivity and the specificity were more than 88%. DATA CONCLUSION: Reference ranges of fetal CTR were established using MRI, which remain constant. These may be helpful in making a definitive diagnosis in fetuses with abnormal development. TECHNICAL EFFICACY: Stage 2.

2.
Postgrad Med J ; 100(1183): 319-326, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38272486

RESUMO

BACKGROUND: The evaluation of patients with fatty liver as defined by metabolic dysfunction-associated fatty liver disease (MAFLD) in the real world remains poorly researched. This study aimed to analyse the clinical and histological features of patients with MAFLD and nonalcoholic fatty liver disease (NAFLD) and to characterize each metabolic subgroup of MAFLD. METHODS: A total of 2563 patients with fatty liver confirmed by ultrasonography and/or magnetic resonance tomography and/or liver biopsy-proven from three hospitals in China were included in the study. Patients were divided into different groups according to diagnostic criteria for MAFLD and NAFLD, and MAFLD into different subgroups. RESULTS: There were 2337 (91.2%) patients fitting the MAFLD criteria, and 2095 (81.7%) fitting the NAFLD criteria. Compared to patients with NAFLD, those with MAFLD were more likely to be male, had more metabolic traits, higher liver enzyme levels, and noninvasive fibrosis scores. Among the patients with liver biopsy, the extent of advanced fibrosis in cases with MAFLD was significantly higher than those with NAFLD, 31.8% versus 5.2% (P < .001); there was no significant difference in advanced fibrosis between obese cases and lean individuals in MAFLD (P > .05); MAFLD complicated with diabetes had significantly higher advanced fibrosis than those without diabetes (43.3% and 17.2%, respectively; P < .001). CONCLUSIONS: Patients with MAFLD have a higher degree of liver fibrosis than NAFLD patients. In addition, diabetic patients should be screened for fatty liver and liver fibrosis degree.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Feminino , Estudos Transversais , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Pessoa de Meia-Idade , China/epidemiologia , Biópsia , Adulto , Fígado Gorduroso/patologia , Cirrose Hepática/patologia , Ultrassonografia , Fígado/patologia , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética
3.
Biochem Biophys Res Commun ; 604: 88-95, 2022 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-35303684

RESUMO

Circular RNAs (circRNAs), characterized as single-stranded closed circular RNA molecules, have been established to exert pivotal functions in various biological or pathological processes. Nonetheless, the effects and underlying mechanisms concerning circRNAs on the aging and aging-related diseases remain elusive. We herein compared the expression patterns of circRNAs in young and senescent mouse embryonic fibroblasts (MEFs), and uncovered that circRNF169 was dramatically up-regulated in senescent MEFs compared with that in young MEFs. Therefore, we further digged into the role and potential mechanisms of circRNF169 in the senescence of MEFs. The results of senescence-associate-ß-galactosidase staining and BrdU incorporation assay showed that silencing of circRNF169 significantly delayed MEFs senescence and promoted cell proliferation, while ectopic expression of circRNF169 exhibited the opposite effects. Moreover, the dual-luciferase reporter assay confirmed that circRNF169 acted as an endogenous miR-30c-5p sponge, which accelerated cellular senescence by sequestering and inhibiting miR-30c-5p activity. Taken together, our results suggested that circRNF169 exerted a crucial role in cellular senescence through sponging miR-30c-5p and represented a promising target for aging intervention.


Assuntos
Senescência Celular , MicroRNAs , RNA Circular , Animais , Proliferação de Células/genética , Senescência Celular/genética , Fibroblastos/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/fisiologia , RNA Circular/genética , RNA Circular/fisiologia
4.
Mol Biol Rep ; 47(6): 4331-4344, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32430848

RESUMO

Auxin response factors (ARFs) are important transcription factors to relay auxin signaling. From the Genome Database for Rosaceae (GDR), we identified 17 peach ARF genes (PpARFs) encoding the proteins with three conserved domains. Their gene structure and functional domains were analyzed. Their transcriptional response to exogenous auxin treatment was tested and confirmed. We also expressed PpARF-GFP fusion reporters in tobacco leaves and observed their nuclear localization by fluorescence microscopy. It has been known that ARFs are widely involved in fruit development. We compared the expression pattern of all PpARFs in different tissues including the fruits at different developmental stages of two peach cultivars, "melting" and "stony hard". We found eight PpARFs were more highly expressed in the "melting" peaches compared to "stony hard" peaches, while three PpARFs were more highly expressed in "stony hard" peaches. Among them, the expression difference of PpARF4, PpARF7 and PpARF12 was large, and their function in regulating fruit development and fruit quality was discussed. Our work provides a basis for further exploring the mechanisms underlying auxin regulated peach fruit ripening.


Assuntos
Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/genética , Prunus persica/genética , Etilenos/biossíntese , Frutas/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Prunus persica/crescimento & desenvolvimento , Prunus persica/metabolismo , Fatores de Transcrição/genética
5.
Exp Brain Res ; 235(3): 941-948, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27942764

RESUMO

Aphasia is a devastating neurological condition affecting a person's ability to communicate and reintegrate into the society. It may occur in 20% or more of patients after stroke. The recovery of language function is accompanied by brain reorganization, and identifying the inter-hemispheric interaction post-stroke will conduce to more targeted treatments. Previous studies suggested that robust homotopic resting-state functional connectivity is a key characteristic of the brain's intrinsic functional architecture, and communication between the left and right cerebral hemispheres is important for language processing. In this study, voxel-mirrored homotopic connectivity (VMHC) was used to examine the inter-hemispheric resting-state functional connectivity (RSFC) differences between 37 patients with acute lacunar stroke in the left hemisphere and 28 healthy controls. Besides, correlation analyses were carried out to investigate the relationship between VMHC values of brain regions showing abnormal inter-hemispheric RSFC and clinical variables [i.e., aphasia quotient (AQ) scores, National Institutes of Health Stroke Scale (NIHSS) and Mini-Mental State Examination of patients]. Compared with healthy controls, patients showed significantly increased VMHC in the pars orbitalis of the inferior frontal gyrus, anterior part of the superior temporal gyrus (STG) and lingual gyrus. No brain region showed decreased VMHC in the patient group than in the healthy control group. The AQ scores were negatively correlated with VMHC values in the STG. NIHSS scores were positively correlated with VMHC values in the lingual gyrus. We hope these results could shed new insights into the pathology of aphasia in patients with acute lacunar stroke.


Assuntos
Afasia , Encéfalo/diagnóstico por imagem , Lateralidade Funcional/fisiologia , Descanso , Acidente Vascular Cerebral Lacunar/complicações , Adulto , Idoso , Afasia/diagnóstico por imagem , Afasia/etiologia , Afasia/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Oxigênio/sangue , Índice de Gravidade de Doença , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem
6.
Hepatol Res ; 47(9): 862-871, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27717156

RESUMO

AIM: Our objective is to explore key changes in brain functions in relation to minimal hepatic encephalopathy (MHE). We incorporated both resting-state functional magnetic resonance imaging (fMRI) and arterial spin labeling (ASL) to enhance the detection of MHE. METHODS: We undertook fMRI scanning for 56 MHE patients and 66 healthy controls. Region functional connectivity was carried out to assess the connectivity status between pairs of regions among 90 brain regions. Additionally, blood flow (BF) status was measured by ASL for all subjects. Spearman's correlation test was implemented to identify any correlation among z-values, results from number connection test type A, and digit symbol tests. Finally, the receiver operating characteristic curve was generated for assessing the accuracy of BF in MHE diagnosis. RESULTS: The corresponding functional connectivity was significantly different between MHE and control groups in 15 regions. For MHE patients, BF showed an increasing pattern in regions of interest. Blood flood in the putamen was positively correlated with number connection test type A neuropsychological performance, whereas it was negatively correlated with the digit symbol test. Blood flood in the right putamen showed the highest value of area under the curve with a sensitivity of 85.7% and specificity of 89.4%. CONCLUSION: Connectivity impairment resulting from ganglia-thalamo-cortical circuits may play important roles in mediating the development of MHE patients. An increase in the BF, particularly in the right putamen, may be considered as evidence for the presence of MHE.

7.
Surg Radiol Anat ; 39(6): 657-662, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27864594

RESUMO

PURPOSE: To investigate the shape of right auricule on 256-slice computed tomography (CT). MATERIALS AND METHODS: Five hundred people (250 men, age range 16-84 years) who had cardiac multidetector CT angiography were recruited in this study. All patients had normal sinus rhythm with normal blood pressure (<140/90 mmHg for systolic/diastolic pressure). The morphology of the right auricule was studied and compared after reconstruction of the raw images. RESULTS: All patients successfully had cardiac CT angiography (100%), and the right auricule morphology was divided into five types and nine subtypes, including Type I of triangular shape (Ia and Ib), Type II of M shape (IIa and IIb), Type III of L shape (IIIa and IIIb), Type IV of reverse L shape (IVa and IVb), and Type V of balanced shape. The most common type of right auricule is Type IV (28.4%) followed by Type II (24.0%), whereas the least common is Type V (11.0%). Type Ia was present significantly (P < 0.0001) more frequently in females than in males, whereas Type IIa significantly (P = 0.042) more frequently in males than females. No other significant (P > 0.05) sex difference existed in the constitution ratio of the types. The normal angle was greater in Type Ib than in Ia. The greater the normal angle in Type I, the greater the deviation of the right auricule tip towards the left. CONCLUSION: A good understanding of the right auricule anatomical morphology can better guide atrial pacing, radiofrequency ablation and other surgical procedures while preventing possible intra-procedural complications.


Assuntos
Átrios do Coração/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(2): 191-6, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-25924427

RESUMO

OBJECTIVE: To study the change of immune status of umbilical cord mesenchymal stem cells (UCMSC) stimulated by toll like receptor 7 (TLR7) agonist CL264. METHODS: TLR7 specific ligand CL264 was used to stimulate the UCMSC. Flow cytometry was conducted to assay the expression of co-stimulators [human leukocyte antigen (HLA)-E, CD80 and CD86] and surface markers of stem cells (CD29, CD59 and CD90). Quantitative PCR was applied to measure the expression variation of immune-related molecules and stem cell markers. Cell differentiation experiment was used to study the change of differentiation ability of UCMSC upon CL264 stimulation. Peripheral blood mononuclear cells (PBMC) were isolated from healthy human and then cocultured with UCMSC in the presence of CL264. Cytotoxicity assay was used to measure the attack of PBMC to UCMSC. RESULTS: Expression of cotimulatory molecules CD86 and HLA-E were enhanced in UCMSC upon CL264 stimulation. Real-time PCR indicated that many pro-inflammatory molecules [interleukin (IL)-1beta, IL-6, IL-8, IL-10, interferon (IFN)-beta, IFN-gamma, nuclear factor-KB (NF-kappaB), transforming growth factor-beta (TGF-beta)] were induced in the presence of CL264 while the expression of stem cells markers were inhibited [Kruppel-like factor-4 (Klf4), Nestin, SRY-related high-mobility-group-box protein-2 (Sox2), Lin28]. Activation of TLR7 also increased the immune attack of PBMC on UCMSC. Our study also indicated that the treatment of CL264 did not influence the differentiation ability of UCMSC. CONCLUSION: TLR7 agonist CL264 could increase the immunogenicity of UCMSC.


Assuntos
Células-Tronco Mesenquimais/citologia , Receptor 7 Toll-Like/agonistas , Cordão Umbilical/citologia , Diferenciação Celular , Técnicas de Cocultura , Citocinas/metabolismo , Humanos , Imunossupressores , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/metabolismo , Leucócitos Mononucleares , Células-Tronco Mesenquimais/efeitos dos fármacos , NF-kappa B/metabolismo
9.
Cell Mol Biol Lett ; 19(1): 140-57, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24569981

RESUMO

Mesenchymal stem cells (MSCs) have both multi-lineage differentiation potential and immunosuppressive properties, making them ideal candidates for regenerative medicine. However, their immunosuppressive properties potentially increase the risk of cancer progression and opportunistic infections. In this study, MSCs isolated from human umbilical cord blood (UCMSCs) and adult bone marrow (BMMSCs) were infected with human cytomegalovirus (HCMV). Cytopathic changes were observed 10 days post infection. PCR products amplified from genomic DNA and cDNA were used to confirm the HCMV infection of the UCMSCs and BMMSCs. Real-time PCR was conducted to quantify the expression of immunomodulatory molecules, including cytokines, chemokines, growth factors, adhesion molecules and cancer-related genes. Our results indicate high upregulation of the majority of these molecules, including many growth factors, tumor necrosis factor alpha, interleukin-8, interleukin-6 and interferon gamma. Adhesion molecules (VCAM-1, TCAM-1 and selectin-E) were downregulated in the infected UCMSCs and BMMSCs. Antibody chip array evaluation of cell culture media indicated that the growth factor secretion by UCMSCs and BMMSCs was greatly influenced (p < 0.001) by HCMV. The stimulation of MSCs with HCMV led to the activation of downstream signaling pathways, including pSTAT3 and Wnt2. Our results show that HCMV can significantly alter the functions of both UCMSCs and BMMSCs, although not in the same way or to the same extent. In both cases, there was an increase in the expression of proangiogenic factors in the microenvironment following HMCV infection. The discrepancy between the two cell types may be explained by their different developmental origin, although further analysis is necessary. Future studies should decipher the underlying mechanism by which HCMV controls MSCs, which may lead to the development of new therapeutic treatments.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/virologia , Citomegalovirus/patogenicidade , Regulação da Expressão Gênica , Humanos , Células-Tronco Mesenquimais/virologia , Cordão Umbilical/citologia , Cordão Umbilical/virologia
10.
Front Microbiol ; 15: 1406661, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957617

RESUMO

In recent years, the rise in greenhouse gas emissions from agriculture has worsened climate change. Efficiently utilizing agricultural waste can significantly mitigate these effects. This study investigated the ecological benefits of returning peach branch waste to fields (RPBF) through three innovative strategies: (1) application of peach branch organic fertilizer (OF), (2) mushroom cultivation using peach branches as a substrate (MC), and (3) surface mulching with peach branches (SM). Conducted within a peach orchard ecosystem, our research aimed to assess these resource utilization strategies' effects on soil properties, microbial community, and carbon cycle, thereby contributing to sustainable agricultural practices. Our findings indicated that all RPBF treatments enhance soil nutrient content, enriching beneficial microorganisms, such as Humicola, Rhizobiales, and Bacillus. Moreover, soil AP and AK were observed to regulate the soil carbon cycle by altering the compositions and functions of microbial communities. Notably, OF and MC treatments were found to boost autotrophic microorganism abundance, thereby augmenting the potential for soil carbon sequestration and emission reduction. Interestingly, in peach orchard soil, fungal communities were found to contribute more greatly to SOC content than bacterial communities. However, SM treatment resulted in an increase in the presence of bacterial communities, thereby enhancing carbon emissions. Overall, this study illustrated the fundamental pathways by which RPBF treatment affects the soil carbon cycle, providing novel insights into the rational resource utilization of peach branch waste and the advancement of ecological agriculture.

11.
Sci Total Environ ; 885: 163886, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37142037

RESUMO

Salt-induced weathering is a common phenomenon in stone relics, and its traditional artificial evaluation of severity is greatly affected by subjective consciousness and lacks systematic standards. Here, we propose a hyperspectral evaluation method for quantifying salt-induced weathering on sandstone surfaces in laboratory tests. Our novel approach consists of two parts: data acquisition of microscopic observations of sandstone in salt-induced weathering environments, and machine learning technology for a predictive model. We first obtain the microscopic morphology of sandstone surfaces by near-infrared hyperspectral imaging technique. Then, a salt-induced weathering reflectivity index is proposed according to analyses of spectral reflectance variation. Next, a principal components analysis-Kmeans (PCA-Kmeans) algorithm is applied to bridge the gaps between the salt-induced weathering degree and the associated hyperspectral images. Furthermore, machine learning technologies, such as Random Forest (RF), Support Vector Machine (SVM), Artificial Neural Network (ANN), and K-Nearest Neighbors (KNN), are trained for better evaluating the salt-induced weathering degree of sandstone. Tests demonstrate that the RF algorithm is feasible and active in weathering classification based on spectral data. The proposed evaluation approach is finally applied to the analysis of salt-induced weathering degree on Dazu Rock Carvings.

12.
Biomolecules ; 13(2)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36830642

RESUMO

The highly conserved and dynamically reversible N6-methyladenine (m6A) modification has emerged as a critical gene expression regulator by affecting RNA splicing, translation efficiency, and stability at the post-transcriptional level, which has been established to be involved in various physiological and pathological processes, including glycolipid metabolism and the development of glycolipid metabolic disease (GLMD). Hence, accumulating studies have focused on the effects and regulatory mechanisms of m6A modification on glucose metabolism, lipid metabolism, and GLMD. This review summarizes the underlying mechanism of how m6A modification regulates glucose and lipid metabolism-related enzymes, transcription factors, and signaling pathways and the advances of m6A regulatory mechanisms in GLMD in order to deepen the understanding of the association of m6A modification with glycolipid metabolism and GLMD.


Assuntos
Epigênese Genética , RNA , Metilação , RNA/metabolismo , Metabolismo dos Lipídeos
13.
Front Microbiol ; 14: 1223420, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485500

RESUMO

Peach branches is a by-product of peach industry. Making peach branch waste into peach branch organic fertilizer (PBOF) is a promising strategy of ecological utilization. In this study, the effects of PBOF on the yield and quality of peach fruit, chemical properties of bulk soil, and soil bacterial communities were investigated in a peach orchard. The results showed that the yield and sugar/acid ratio of two high-level PBOF treatments (SDH.4 and SKR.4) was higher than no fertilization treatment (CK), but there was no significant difference compared to the commercial organic fertilizer treatment (SYT.4). Moreover, the three fertilizer treatments increased soil nutrients such as soil organic matter (SOM) and available potassium (AK), compared to CK. Furthermore, PBOF increased the relative abundance of beneficial bacteria, and enhanced the soil bacterial co-occurrence pattern and the potential function of bacterial communities to degrade exogenous compounds. In addition, thanks to the local policy of encouraging the use of PBOF, the use cost of PBOF is lower than commercial organic fertilizer, which is conducive to the development of ecological agriculture.

14.
Environ Sci Pollut Res Int ; 30(44): 99666-99674, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37620694

RESUMO

Negative air ion (NAI) is an important index for measuring air quality and has been widely recognized to be influenced by photosynthesis processes. However, vegetation type and light intensity are also known to impact NAI, contributing to significant uncertainties in the relationship between light and NAI. In this paper, we selected Pinus bungeana, Platycladus orientalis and Buxus sinica as research subjects and obtained their NAI, light intensity, and meteorological data through synchronous observation under the relatively stable condition of the phytotron. We analyzed the change characteristics of NAI and the difference of NAI production ability in needle and broadleaf vegetation under different light intensities. Finally, we determined the relationship and underlying mechanism governing light intensity and NAI using diverse tree species. The results showed that the influence of light on NAI was significant. In the environment without vegetation, the influence of different light intensities on NAI was not significant, and the mean NAI concentration was 310 ions·cm-3. Conversely, in the presence of vegetation, NAI showed a "single-peak" trend with increasing light intensity. The NAI concentration of the three tree species was significantly higher than under different light intensities when vegetation was not present. The NAI promoting ability of P. bungeana was the highest (675 ions·cm-3), followed by P. orientalis (478 ions·cm-3) and B. sinica (430 ions·cm-3), which increased by 117.5%, 53.9% and 38.6% compared to the environment without vegetation. The NAI growth rate was significantly different between needle and broadleaf vegetation based on the specific tridimensional green biomass. Additionally, the NAI growth rates of P. bungeana and P. orientalis were 647 and 295 ions·cm-3·m-3, respectively, which were 3.06 and 1.39 times that of B. sinica (211 ions·cm-3·m-3). The piecewise equation fitting effect of NAI and light intensity was better for different tree species, the determination coefficients (R2) of P. bungeana, P. orientalis and B. sinica were 0.926, 0.916 and 0.880, and the root mean square errors (RMSE) were 7.157, 6.008 and 5.389 ion·cm-3, respectively. Altogether, our study provides a theoretical basis as well as technical support for the construction of healthy vegetation stands, the selection of preferred tree species, and the optimization of vegetation models, and promotes air quality and the provision of ecosystem functions and services.


Assuntos
Ecossistema , Árvores , Humanos , Íons , Biomassa , Luz
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(10): 2805-9, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23285891

RESUMO

Rapid determination of biomass feedstock properties is of value for the production of biomass densification briquetting fuel with high quality. In the present study, visible and near-infrared (Vis-NIR) spectroscopy was employed to build prediction models of componential contents, i. e. moisture, ash, volatile matter and fixed-carbon, and calorific value of three selected species of agricultural biomass feedstock, i. e. pine wood, cedar wood, and cotton stalk. The partial least squares (PLS) cross validation results showed that compared with original reflection spectra, PLS regression models developed for first derivative spectra produced higher prediction accuracy with coefficients of determination (R2) of 0.97, 0.94 and 0.90, and residual prediction deviation (RPD) of 6.57, 4.00 and 3.01 for ash, volatile matter and moisture, respectively. Good prediction accuracy was achieved with R2 of 0.85 and RPD of 2.55 for fixed carbon, and R2 of 0.87 and RPD of 2.73 for calorific value. It is concluded that the Vis-NIR spectroscopy is promising as an alternative of traditional proximate analysis for rapid determination of componential contents and calorific value of agricultural biomass feedstock


Assuntos
Produtos Agrícolas/química , Eliminação de Resíduos/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Madeira/química , Fontes de Energia Bioelétrica , Caules de Planta/química
16.
Arch Gynecol Obstet ; 283(6): 1385-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20628750

RESUMO

OBJECTIVE: The purpose of this study was to investigate the prevalence of human papillomavirus (HPV) genotypes infection in women with and with normal cervical histology in the littoral region of Shandong, China. METHODS: Scrape specimens were collected from 4,601 women for Pap smear and HPV genotypes identification. 1,489 women without normal cytology or with cervical disease were referred for colposcopic examination and biopsy procedures. RESULTS: The HPV infection in healthy women of the littoral region of Shandong (9.61%) is lower than that observed in previous studies in China and much less than in the high-risk areas. HPV infection prevalence was 14.23% in cervicitis with normal cervical histology, which was significantly lower than that of the women without normal cervical histology (60.12%, P = 0.00). Compared to prevalence of high-risk (HR) HPV genotypes (11.04%) in cervicitis with normal cervical histology, HR HPV genotypes prevalence (59.82%) was significantly higher in women without normal cervical histology (P = 0.003). HPV types 16, 52, 58, and 31 were the most prevalent HPV genotypes found in women without normal cervical histology. No statistical difference was observed for multiple HR HPV genotypes infection between women with and without normal cervical histology (P = 0.892). CONCLUSION: Compared with prevalence rates for other populations, the prevalence of specific-HPV genotypes infecting women is different in the littoral region of Shandong Province, China.


Assuntos
Genótipo , Teste de Papanicolaou , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Cervicite Uterina/epidemiologia , Cervicite Uterina/patologia , Esfregaço Vaginal , Adulto , Biópsia , Colo do Útero/patologia , Colo do Útero/virologia , China , Colposcopia , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Cervicite Uterina/virologia , Adulto Jovem , Displasia do Colo do Útero/virologia
17.
Open Life Sci ; 15(1): 890-901, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33817276

RESUMO

Peach brown rot caused by Monilinia fructicola is one of the most economically destructive diseases of peach (Prunus persica L.) in some orchards of China. Biocontrol is a significant strategy that exhibits strong levels of control and ecologically sound concepts in disease management. The purpose of this study was to investigate the combined suppressive effects of three endophytic bacterial strains (xj-14, xj-15, and xj-16) and two soil rhizosphere bacterial strains (xj-A and xj-C) that were shown to have strong inhibitory activity toward M. fructicola in our previous study. The optimal strains and the optimized combination of strains were determined. The combination of strains xj-15 and xj-C inhibited M. fructicola more intensively for a longer period of time. Following the application of 1 × 109 CFU/mL bacterial complex to the fruits, leaves, and shoots of peach trees infected with M. fructicola, the rate of inhibition reached 73.80%, 83.33%, and 90.43%, respectively. A pot experiment using lettuce (Lactuca sativa) showed that inoculation with the bacterial complex significantly increased the growth of seedlings. In this study, some compound bacteria were more effective than those in previous study in suppressing disease and promoting growth, which have the potential to be further applied in the field.

18.
Gastroenterol Res Pract ; 2020: 6268570, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32565783

RESUMO

BACKGROUND AND AIMS: Computed tomography portal venography (CTPV) shows potential in detecting varices that need treatment and their drainage pathways. However, its agreement with endoscopy requires further study. We investigated the feasibility of CTPV as an alternative tool to endoscopy in screening gastroesophageal varices (GEVs) and developed a CTPV-based model to provide a less invasive assessment of endotherapy for cirrhotic patients with GEVs. METHODS: The study included 33 cirrhotic patients with a recent history of variceal hemorrhage. The presence, grade, and classification of GEVs on endoscopy and CTPV were compared (kappa test). Twenty-four patients were treated endoscopically, including 12 for esophageal varices (EVs), 8 for gastric varices (GVs), and 4 for GEVs. Treatment efficacies were assessed with the newly developed CTPV-based method at 1 week and 1 month after treatment. Efficiency evaluated by CTPV and endoscopy was compared by Fisher's exact test to determine whether CTPV is efficient in the assessment of endotherapy efficacy. RESULTS: For the screening and grading/classification of EVs and GVs, substantial agreement (EV kappa: 0.63 and 0.68; GV kappa: 0.62 and 0.75, respectively) was noted between endoscopy and CTPV. The therapeutic efficacy of EVs was higher when assessed by CTPV than when evaluated by endoscopy (37.50% vs. 12.50% at 1 week postoperation, P = 0.22; 62.50% vs. 25.00% at 1 month postoperation, P = 0.07), but without statistical significance. The same trend was also found in the assessment of therapeutic efficacy for GVs (25.00% vs. 16.67% at 1 week postoperation, P = 1; 58.33% vs. 41.67% at 1 month postoperation, P = 0.68). CONCLUSION: CTPV is comparable to endoscopy in the detection of GEVs and in the evaluation of endotherapy efficacy, which suggests that it could be a less invasive alternative for endoscopy in cirrhotic patients with GEVs needing treatment.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(6): 1607-10, 2009 Jun.
Artigo em Zh | MEDLINE | ID: mdl-19810542

RESUMO

Handheld SPAD meter is often used to measure chlorophyll content of plant and nitrogen level for some species. For plant production automation, however, it loses its popularity due to its point-by-point checking. The authors need to monitor the growing conditions of plant remotely, instantly and nondestructively. In the test, we examined optical fiber reflection spectroscopy used to measure chlorophyll content of some plant leaves, or for their SPAD prediction. The authors picked 120 leaves randomly from our campus ground or trees, among which 70 samples were chosen as calibration set and others as verification set. Each sample was water-cleaned and air-dried. To locate each measuring point precisely when using SPAD meter and spectrometer, the authors drew a circle with a diameter of 10 mm on each leave to be measured. By comparing the spectral curves of various leaves, the authors found that the spectral band between 650-750 nm was significant for SPAD modeling since this range of spectral data of leaves with the same SPAD reading was close to each other. It was showed that leave color was an unnecessary factor for SPAD prediction by reflection spectroscopy. Besides, the authors discovered that LED's narrow spectral range used by SPAD meter should be concerned because optical fiber spectrometer has much more wide spectral range. Based on this awareness, the authors designed an adjustment factor of light to linearly rebuild spectrometer's reflective intensity so that it reached zero outside the band 650-750 nm. Moreover, leave thickness was another influential factor for SPAD prediction since the light of SPAD meter goes through the leave while the reflective spectrometer does not. First, an equation for SPAD prediction was built with uncertain parameters. Then, a standard genetic algorithm was designed with Visual Basic 6.0 for parameter optimization. As a result, the optimal reflection band was narrowed within 683.24-733.91 nm. The result showed that leave thickness strongly affects the precision of SPAD prediction. Through the modification of leave thickness, the regression coefficient (R2) of calibration set and verification set reached 0.865 8 and 0.916 1 respectively. The test showed that optical fiber reflection spectroscopy is useful for SPAD prediction and can be used to develop remote SPAD sensor.


Assuntos
Folhas de Planta/química , Plantas/química , Análise Espectral , Absorção , Algoritmos , Clorofila/análise , Modelos Logísticos
20.
PLoS One ; 14(7): e0220299, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344114

RESUMO

Bosten Lake is an important region of Northwest China that has transformed from a freshwater lake to a saltwater lake since the 1970s. The water quality in the Bosten Lake basin is important for social and economic development, and nitrogen (N) and phosphorus (P) are the key indicators of water quality. The land use data, precipitation data and Digital Elevation Model (DEM) data with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model were used to simulate the N and P exports of the Bosten Lake basin. The spatial and temporal dynamics of nitrogen and phosphorus exports, and the response of nitrogen and phosphorus exports to land use change and precipitation change were analyzed between 2000 and 2015. The results show that the amount of N and P exports increased during 2000-2015, and the N and P exports are mainly distributed around Bosten Lake. The N and P exports are greatly affected by cultivated land, built-up areas and grassland, while they are less affected by other land use types. The high precipitation areas with small exports of N and P are mainly distributed in mountain areas, while small precipitation areas with large exports of N and P are distributed in plains where the cultivated land and built-up areas are concentrated. The InVEST model can be used in Northwest China, and the statistical downscaling of reanalysis precipitation data can be used in the InVEST model to improve the simulation accuracy in the data scarce regions of Northwest China.


Assuntos
Lagos/química , Nitrogênio/análise , Fósforo/análise , Qualidade da Água , China , Ecossistema , Monitoramento Ambiental/métodos , Água Doce/química , Modelos Biológicos , Água do Mar/química , Poluentes Químicos da Água/análise
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