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1.
Scand J Gastroenterol ; 59(2): 133-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37752679

RESUMO

BACKGROUND: Gastrointestinal motility disorders tend to develop after pancreaticoduodenectomy (PD). The objectives of this study were: (1) to investigate the impact of needleless transcutaneous neuromodulation (TN) on the postoperative recuperation following pancreaticoduodenectomy (PD), and (2) to explore the underlying mechanisms by which TN facilitates the recovery of gastrointestinal function after PD. METHODS: A total of 41 patients scheduled for PD were randomized into two groups: the TN group (n = 21) and the Sham-TN group (n = 20). TN was performed at acupoints ST-36 and PC-6 twice daily for 1 h from the postoperative day 1 (POD1) to day 7. Sham-TN was performed at non-acupoints. Subsequent assessments incorporated both heart rate variation and dynamic electrogastrography to quantify alterations in vagal activity (HF) and gastric pacing activity. RESULTS: 1)TN significantly decreased the duration of the first passage of flatus (p < 0.001) and defecation (p < 0.01) as well as the time required to resume diet (p < 0.001) when compared to sham-TN;2)Compared with sham-TN, TN increased the proportion of regular gastric pacing activity (p < 0.01);3) From POD1 to POD7, there was a discernible augmentation in HF induced by TN stimulation(p < 0.01);4) TN significantly decreased serum IL-6 levels from POD1 to POD7 (p < 0.001);5) TN was an independent predictor of shortened hospital stay(ß = - 0.349, p = 0.035). CONCLUSION: Needleless TN accelerates the recovery of gastrointestinal function and reduces the risk of delayed gastric emptying in patients after PD by enhancing vagal activity and controlling the inflammatory response.


Assuntos
Pancreaticoduodenectomia , Estômago , Humanos , Pancreaticoduodenectomia/efeitos adversos , Tempo de Internação , Esvaziamento Gástrico , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia
2.
BMC Geriatr ; 23(1): 828, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38066433

RESUMO

PURPOSE: Older individuals are priority coronavirus disease 2019 (COVID-19) vaccine recipients. Our aim was to investigate the prevalence of and factors influencing vaccine hesitancy in older individuals living in nursing homes and communities. METHODS: A self-administered COVID-19 vaccine hesitancy survey was conducted from September 2021 to December 2021 among people aged ≥ 60 years in eight nursing homes (382 participants) and the community (112 participants) in Taizhou, China. The response rate was 72.1% (382/530) for older adults in nursing homes and 68.7% (112/163) for older adults in the community. RESULTS: We found that 58.1% of the older individuals in nursing homes and 36.6% of those in the community were hesitant to receive the COVID-19 vaccine and that there was a statistically significant difference (P < 0.001). Multiple logistic regression results indicated that the main factors influencing hesitation among the older individuals in nursing homes were being male (Odds Ratio (OR) = 1.67, 95% Confidence Interval (CI): 1.01-2.76); their cognitive level, including having a high perceived risk of COVID-19 infection (OR = 3.06, 95% CI: 1.73-5.43) or the perception of low vaccine safety (OR = 3.08, 95% CI: 1.545- 6.145); anxiety (OR = 3.43, 95% CI: 1.96-5.99); and no previous influenza vaccination (OR = 1.82, 95% CI: 1.13-2.93); whereas those for older individuals in the community were comorbid chronic diseases (OR = 3.13, 95% CI: 1.11- 8.78) and community workers not recommending the vaccine (OR = 8.223, 95% CI: 1.77-38.27). CONCLUSION: The proportion of older individuals in nursing homes who were hesitant to receive the COVID-19 vaccine was significantly higher than for older individuals in the community. Targeted measures should be implemented to reduce vaccine hesitancy and improve vaccination rates in response to the special environment of nursing homes and the characteristics of this population.


Assuntos
COVID-19 , Humanos , Masculino , Idoso , Feminino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Vacinação , China/epidemiologia , Casas de Saúde
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(7): 726-731, 2023 Jul 15.
Artigo em Zh | MEDLINE | ID: mdl-37529955

RESUMO

OBJECTIVES: To study the genetic characteristics, clinical characteristics, and prognosis of children with primary dilated cardiomyopathy (DCM). METHODS: A retrospective analysis was performed on the medical data of 44 children who were diagnosed with DCM in Hebei Children's Hospital from July 2018 to February 2023. According to the genetic testing results, they were divided into two groups: gene mutation-positive group (n=17) and gene mutation-negative group (n=27). The two groups were compared in terms of clinical data at initial diagnosis and follow-up data. RESULTS: Among the 44 children with DCM, there were 21 boys (48%) and 23 girls (52%). Respiratory symptoms including cough and shortness of breath were the most common symptom at initial diagnosis (34%, 15/44). The detection rate of gene mutations was 39% (17/44). There were no significant differences between the two groups in clinical characteristics, proportion of children with cardiac function grade Ⅲ or Ⅳ, brain natriuretic peptide levels, left ventricular ejection fraction, and left ventricular fractional shortening at initial diagnosis (P>0.05). The median follow-up time was 23 months, and 9 children (20%) died, including 8 children from the gene mutation-positive group, among whom 3 had TTN gene mutation, 2 had LMNA gene mutation, 2 had TAZ gene mutation, and 1 had ATAD3A gene mutation. The gene mutation-positive group had a significantly higher mortality rate than the gene mutation-negative group (P<0.05). CONCLUSIONS: There is no correlation between the severity of DCM at initial diagnosis and gene mutations in children. However, children with gene mutations may have a poorer prognosis.


Assuntos
Cardiomiopatia Dilatada , Função Ventricular Esquerda , Masculino , Feminino , Humanos , Criança , Volume Sistólico , Estudos Retrospectivos , Fenótipo , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/diagnóstico , Mutação , ATPases Associadas a Diversas Atividades Celulares/genética , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética
4.
Mol Pain ; 18: 17448069211053255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35057644

RESUMO

N-methyl-d-aspartate receptors (NMDARs) dysfunction in the nucleus accumbens (NAc) participates in regulating many neurological and psychiatric disorders such as drug addiction, chronic pain, and depression. NMDARs are heterotetrameric complexes generally composed of two NR1 and two NR2 subunits (NR2A, NR2B, NR2C and NR2D). Much attention has been focused on the role of NR2A and NR2B-containing NMDARs in a variety of neurological disorders; however, the function of NR2C/2D subunits at NAc in chronic pain remains unknown. In this study, spinal nerve ligation (SNL) induced a persistent sensory abnormity and depressive-like behavior. The whole-cell patch clamp recording on medium spiny neurons (MSNs) in the NAc showed that the amplitude of NMDAR-mediated excitatory postsynaptic currents (EPSCs) was significantly increased when membrane potential held at -40 to 0 mV in mice after 14 days of SNL operation. In addition, selective inhibition of NR2C/2D-containing NMDARs with PPDA caused a larger decrease on peak amplitude of NMDAR-EPSCs in SNL than that in sham-operated mice. Appling of selective potentiator of NR2C/2D, CIQ, markedly enhanced the evoked NMDAR-EPSCs in SNL-operated mice, but no change in sham-operated mice. Finally, intra-NAc injection of PPDA significantly attenuated SNL-induced mechanical allodynia and depressive-like behavior. These results for the first time showed that the functional change of NR2C/2D subunits-containing NMDARs in the NAc might contribute to the sensory and affective components in neuropathic pain.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Depressão/etiologia , Humanos , Camundongos , Núcleo Accumbens , Traumatismos dos Nervos Periféricos/complicações , Receptores de N-Metil-D-Aspartato/metabolismo
5.
Mol Pain ; 18: 17448069221126078, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-36039405

RESUMO

Ginsenoside Rh2 is one of the major bioactive ginsenosides in Panax ginseng. Although Rh2 is known to enhance immune cells activity for treatment of cancer, its anti-inflammatory and neuroprotective effects have yet to be determined. In this study, we investigated the effects of Rh2 on spared nerve injury (SNI)-induced neuropathic pain and elucidated the potential mechanisms. We found that various doses of Rh2 intrathecal injection dose-dependently attenuated SNI-induced mechanical allodynia and thermal hyperalgesia. Rh2 also inhibited microglia and astrocyte activation in the spinal cord of a murine SNI model. Rh2 treatment inhibited SNI-induced increase of proinflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1 and IL-6. Expression of miRNA-21, an endogenous ligand of Toll like receptor (TLR)8 was also decreased. Rh2 treatment blocked the mitogen-activated protein kinase (MAPK) signaling pathway by inhibiting of phosphorylated extracellular signal-regulated kinase expression. Finally, intrathecal injection of TLR8 agonist VTX-2337 reversed the analgesic effect of Rh2. These results indicated that Rh2 relieved SNI-induced neuropathic pain via inhibiting the miRNA-21-TLR8-MAPK signaling pathway, thus providing a potential application of Rh2 in pain therapy.


Assuntos
Ginsenosídeos , MicroRNAs , Neuralgia , Fármacos Neuroprotetores , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Hiperalgesia/tratamento farmacológico , Interleucina-6 , Ligantes , Camundongos , MicroRNAs/genética , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptor 8 Toll-Like , Fator de Necrose Tumoral alfa/metabolismo
6.
Biomed Chromatogr ; 34(1): e4701, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31596954

RESUMO

Patrinia villosa (Thunb.) Juss. (PVJ) is described as pungent, bitter and slightly cold in Chinese medicine, and is associated with the large intestine, stomach and liver meridians. The preliminary experiments of our research team proved that PVJ total flavonoids have excellent inhibitory effects on liver cancer cells. The present experiment uses the UPLC-Q-TOF-MS technology and serum pharmacochemistry methods to analyze the chemical components in vitro and in vivo of PVJ antiliver tumors. A total of 14 chemical components were identified in the total flavonoids extract of PVJ, and it is mainly composed of flavonoids, flavonones, flavonols and phenolic acids. At the same time, seven prototypical components and seven metabolic components were detected in the drug-containing plasma. Hydrocaffeate and scutellarein are the phase I metabolites of caffeic acid and scutellarin, respectively. Sulfated apigenin, sulfated luteolin, sulfated kaempferol and methylated kaempferol are the II phase metabolites of apigenin, luteolin, kaempferol, respectively. The experiment provides a reference for the research and development of antitumor drug candidates, and provides a basis for revealing the bioactive components of PVJ and the antitumor mechanism.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/sangue , Patrinia/química , Extratos Vegetais/sangue , Animais , Flavonoides/química , Masculino , Espectrometria de Massas , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(5): 716-719, 2018 Sep.
Artigo em Zh | MEDLINE | ID: mdl-30378332

RESUMO

OBJECTIVE: To explore the cytotoxicity of concentrate growth factors (CGF) and the effects on the apoptosis, proliferation and differentiation of human dental pulp cells (hDPCs), which were closely correlated with future application of CGF in the treatment of dental pulpal and periapical diseases. METHODS: hDPCs were isolated from permanent teeth extracted for orthodontic purpose, and expanded in vitro. hDPCs were treated with CGF and mineral trioxide aggregate (MTA) respectively. The cell apoptosis, proliferation, cell cycle and ALP activity were analyzed after 1, 3 and 7 days. RESULTS: Compared with the MTA group, CGF significantly promoted cell proliferation, increased the proportion of S-phase cells and ALP activity on days 3 and 7 (P<0.01). Besides, hDPCs apoptotic rates decreased in CGF group. CONCLUSION: CGF has a good ability to promote the proliferation of dental pulp cells, resist apoptosis and induce osteogenic/odontogenic differentiation in vitro.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Polpa Dentária/citologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Células Cultivadas , Polpa Dentária/efeitos dos fármacos , Humanos , Osteogênese
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 566-70, 2017 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30291819

RESUMO

Soil organic matter (SOM) is one of the most important measuring indexes of soil fertility. How to predict SOM spatial distribution precisely has great significance to soil carbon storage estimation and precision agriculture development. Traditional measurement of SOM, although with higher accuracy, consumes a lot of labor resources and costs long-term monitoring period, therefore, it is hard to achieve dynamic monitor of SOM. Spectroscopy technique has been used in SOM and other soil physicochemical parameters quick measurement. However spatial inversion model accuracy of SOM based on remote sensing images is relatively lower than laboratory model accuracy due to the influence of soil moisture, roughness and so on. In recent years, most studies have not eliminated the effect of moisture. Since moisture has great influence on SOM spectra reflectance, this study introduced the temporal information combined with the spectral information in order to solve this problem. Soil moisture has differences in multi period remote sensing images, and the spectra reflectance is also different. Based on the combination of reflectance from of two periods remote sensing images, the spectral index was constructed to predict SOM in this study. MODIS images of study area acquired in this study area (Blacksoil zone) because of the advantage of high temporal resolution. Spectra reflectance of MODIS images were used to analyze the effect of moisture on soil spectral reflectance, and then the spectral prediction models of SOM were built based on the comprehensive impacts of SOM and soil moisture. The results shows that: (1) the accuracy of SOM prediction model based on single image was lower without consideration of moisture effect, The Root mean square error (RMSE) of SOM prediction model were 0.591, 0.522, 0.545, 0.553, and the determination coefficient (R(2)) were 0.505, 0.614, 0.562, 0.568, 0.645 respectively based on the day of year (DOY) 117, 119, 130, 140, 143 single image. (2) Model with multi temporal images (DOY119 and 143) which considered the effect of moisture and SOM showed better predictive ability. RMSE was 0.442 while R2 was 0.723. Therefore the accuracy and stability of the model were significantly improved, and it can be used to predict the spatial distribution of SOM in regional scale. This study provides important information for regional soil fertility evaluation, soil carbon storage estimation, and precision agriculture development.

9.
BMC Bioinformatics ; 17 Suppl 9: 266, 2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27454113

RESUMO

BACKGROUND: The planted (l, d) motif search (PMS) is an important yet challenging problem in computational biology. Pattern-driven PMS algorithms usually use k out of t input sequences as reference sequences to generate candidate motifs, and they can find all the (l, d) motifs in the input sequences. However, most of them simply take the first k sequences in the input as reference sequences without elaborate selection processes, and thus they may exhibit sharp fluctuations in running time, especially for large alphabets. RESULTS: In this paper, we build the reference sequence selection problem and propose a method named RefSelect to quickly solve it by evaluating the number of candidate motifs for the reference sequences. RefSelect can bring a practical time improvement of the state-of-the-art pattern-driven PMS algorithms. Experimental results show that RefSelect (1) makes the tested algorithms solve the PMS problem steadily in an efficient way, (2) particularly, makes them achieve a speedup of up to about 100× on the protein data, and (3) is also suitable for large data sets which contain hundreds or more sequences. CONCLUSIONS: The proposed algorithm RefSelect can be used to solve the problem that many pattern-driven PMS algorithms present execution time instability. RefSelect requires a small amount of storage space and is capable of selecting reference sequences efficiently and effectively. Also, the parallel version of RefSelect is provided for handling large data sets.


Assuntos
Biologia Computacional/métodos , Proteínas/química , Algoritmos , Motivos de Aminoácidos , Domínios Proteicos , Proteínas/genética , Análise de Sequência de Proteína , Software
10.
J Theor Biol ; 395: 186-193, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26869212

RESUMO

Identifying protein complexes from Protein-protein Interaction Networks (PINs) is fundamental for understanding protein functions and activities in cell. Based on the assumption that protein complexes are highly connected areas in PINs, many algorithms were proposed to identify protein complexes from PINs. However, most of these approaches neglected that not all proteins in complexes are highly connected, and proteins in PINs with different topological properties may form protein complexes in different ways and should be treated differently. In this paper, we proposed a double-layer clustering method based on the power-law distribution (PLCluster). To calculate the centrality scores of nodes, we proposed a Dense-Spread Centrality method. The centrality scores calculated by Dense-Spread Centrality method follow a power-law distribution. Based on the power-law distribution of the centrality scores, PLCluster divides the nodes into two categories: the nodes with very high centrality scores and the nodes with lower centrality scores. Then different strategies are applied to nodes in different categories for detecting protein complexes from the PIN, respectively. Furthermore, the predicted protein complexes, which are inconsistent with the fact that all proteins in a protein complex should be in the same subcellular compartment, are filtered out. Compared with other nine existing methods on a high reliable yeast PIN, PLCluster shows great advantages in terms of the number of known complexes that are identified, Sensitivity, Specificity, f-measure and the number of perfect matches.


Assuntos
Modelos Biológicos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Transporte Proteico
11.
AJR Am J Roentgenol ; 207(4): 797-803, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27505309

RESUMO

OBJECTIVE: The purpose of this study was to compare the efficacy of submucosal enhancement on dynamic contrast-enhanced MRI (DCE-MRI) and detection of a stalk on DWI for differentiating stage T1 from stage T2 bladder urothelial carcinoma. SUBJECTS AND METHODS: Our prospective study was approved by the institutional medical ethics committee and informed consent was obtained from all patients. Fifty-nine patients (92 tumors in total) with urothelial bladder cancer underwent MRI within 2 weeks before surgery. Two image sets of T2-weighted MRI with DWI and T2-weighted with DCE-MRI were interpreted independently at 2-week intervals by two uroradiologists without any knowledge of the surgical or histologic findings. The tumor was categorized as stage T1 or lower when a stalk was evident at the tumor base on DWI or when continuous linear submucosal enhancement was detected in the early phase of DCE-MRI. Tumors without stalks or with discontinuous linear submucosal enhancement were categorized as stage T2. RESULTS: Of the 42 tumors with stalks on DWI, 41 showed continuous and one had discontinuous submucosal enhancement on DCE-MRI. In 50 carcinomas without stalks on DWI, submucosal enhancement was absent in 34, continuous in 12, and discontinuous in four. The staging accuracy of DWI (91.3%, 84/92) and DCE-MRI (91.3%, 84/92) was improved to 94.6% (87/92) by combining the interpretations of both DWI and DCE-MRI. CONCLUSION: Submucosal linear enhancement under the tumor base on DCE-MRI complements tumor stalk detection on DWI for differentiating stage T1 from stage T2 bladder urothelial carcinoma.

12.
Bioprocess Biosyst Eng ; 39(1): 75-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26508324

RESUMO

To further improve the ganoderic acid (GA) production, a novel integrated strategy by combining nitrogen limitation and calcium ion addition was developed. The effects of the integrated combination on the content of GA-T (one powerful anticancer compound), their intermediates (squalene and lanosterol) and on the transcription levels of GA biosynthetic genes in G. lucidum fermentation were investigated. The maximum GA-T content with the integrated strategy were 1.87 mg/ 100 mg dry cell weight, which was 2.1-4.2 fold higher than that obtained with either calcium ion addition or nitrogen limitation alone, and it is also the highest record as ever reported in submerged fermentation of G. lucidum. The squalene content was increased by 3.9- and 2.2-fold in this case compared with either individual strategy alone. Moreover, the transcription levels of the GA biosynthetic genes encoding 3-hydroxy-3-methyglutaryl coenzyme A reductase and lanosterol synthase were also up-regulated by 3.3-7.5 and 1.3-2.3 fold, respectively.


Assuntos
Cálcio/metabolismo , Nitrogênio/metabolismo , Reishi/crescimento & desenvolvimento , Triterpenos/metabolismo , Cálcio/farmacologia
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1813-7, 2016 Jun.
Artigo em Zh | MEDLINE | ID: mdl-30052398

RESUMO

As an important content of the nature, soil has great influence on the formation of ecological system and human life. Therefore, the study of soil's polarized thermal radiation characteristics has great practical significance. There have been few reports about the study of the polarized radiation characteristics of the soil in 2π space. The results showed that the polarized brightness temperature performed nonlinearly as the change of detection angles between 0° to 80°. However, polarized brightness temperature increased greatly when the detection angle changed from 60° to 80°. It also changed under different azimuth angles. The polarized brightness temperature increased as the growth of the azimuth angles in the range of 0° to 240°, but its tendency was opposite in the range between 240° and 320°. The channels and polarized angles both influenced the polarized brightness temperature. Their amplitudes of fluctuation of their own curves were gentle and the temperatures of different agrotype were various. The order was Meadow Soil>Leached Chernozem>Chernozem>Aeolian Soil. These results provide significant foundation to the study about the basic theory of thermal infrared polarization remote sensing.

14.
Zhonghua Nan Ke Xue ; 22(9): 787-791, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29071874

RESUMO

OBJECTIVE: To analyze the MRI manifestations of Peyronie's disease and investigate the value of high-field MRI in the diagnosis of the disease. METHODS: Using a small surface coil, we performed 3.0 Tesla MRI for 14 patients with clinically diagnosed Peyronie's disease. The MRI protocol included routine sequences (T1WI, T2WI, and enhanced T1WI) and susceptibility-weighted imaging (SWI). Each patient had received 2-4 penile ultrasound examinations previously. We compared the MRI findings with the results of ultrasonography. RESULTS: MRI manifested 25 penile plaques in the 14 patients, 3 (7 plaques) with inflammation, 4 (8 plaques) with fibrosis, and the other 7 (10 plaques) with calcification displaying a low signal intensity on SWI. Ultrasonography had revealed the 10 calcified plaques in all the 20 examinations, but exhibited the 7 inflammatory and 8 fibrotic ones in only 3 of the 23 examinations. The combination of MRI SWI sequences was necessitated for the detection of calcified plaques and achieved higher detection rates than ultrasonography for inflammatory and fibrotic plaques (P<0.05). CONCLUSIONS: High-field MRI has high sensitivity and accuracy in the diagnosis of Peyronie's disease, which can effectively display penile plaques of different nature in the early stage through multi-parametric sequences.


Assuntos
Calcinose/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Induração Peniana/diagnóstico por imagem , Fibrose , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pênis/diagnóstico por imagem , Pênis/patologia , Sensibilidade e Especificidade , Ultrassonografia
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 408-12, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27209740

RESUMO

Cyclobutanol (C4H8O) is one of the four-membered ring type molecules, which usually adopts a non-planar equilibrium conformation, and the substituent group OH can adopt two positions relative to the puckered ring, the axial or the equatorial, giving rise to an additional degree of freedom and various molecular conformations. Additionally, temperature is one important thermodynamic parameter that greatly influents the structure and induces the possibility of conformational change or crystal change. As a consequence, there may be a number of phase transitions and molecular conformations for cyclobutanol under different temperature. In this paper, Raman and infrared spectroscopic technique were applied to investigate the vibration modes of cyclobutanol. The results indicate that the main component of the liquid cyclobutanol is equatorial-trans (Eq-t) conformer with a few Eq-g conformers at ambient condition. Then differential scanning calorimetry (DSC) and low temperature Raman spectroscopic were applied to study the phase transition of cyclobutanol during the cooling and heating process. It is observed that the Raman spectra and the intensities of these bands are not significantly changed during the cooling process. The results indicate that there is sill no presence of solidification especially cooling to 140K, which indicates that the cyclobutanol still remains the liquid state and supercooled state is observed during the cooling process. And this supercooled liquid is one metastable state, not in thermodynamic equilibrium. Further cooling to 138 K, the super-cooling liquid cyclobutanol will transform into the glassy state, accompanied with a small change of entropy. During the heating process, as the temperature is raised to 180 K, the Raman peaks became sharper and some new characteristic peaks appeared abruptly and a discontinuous change was observed in bandwidths versus temperature. And these new signatures can be maintained upon to 220 K, and then will disappear as the temperature increasing continuously. This result indicates the one crystal phase transition and a melting transition present at around 180 and 220 K. In addition, it can be observed that the component of Eq-g conformer increases, accompanied with the crystallization during heating at around 180 K. These results were helpful to understand the kinetics of the crystallization process of other small organic molecules.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2585-9, 2016 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30074369

RESUMO

Pixel-based processing method mainly extracts spectral information from hyperspectral remote sensing images, but site specific management zone (SSMZ) delineation and crop yield estimation with images need to take spatiotemporal heterogeneity into account. As the spatial resolution of remote sensing data increases, the so-called "salt-and-pepper" problem of pixel-based classification becomes more serious. The spatiotemporal heterogeneity of soil properties and crop biophysical parameters are mainly delineated with grid sampling and geostatistics interpolation, but the widely used method has some problems: time consuming and high cost. Satellite imageries are introduced to delineate SSMZ, but there are also problems needed to be resolved: (1) single date imagery is used to map SSMZ which is difficult to determine the optimal date for SSMZ delineation; (2) only few SSMZs were mapped, which limited application of site specific fertilizing and management; (3) pixel-based method for SSMZ delineation didn't concern the spatial relationship between pixels and site specific management does not implement at pixel level, but at SSMZ level. To improve the accuracy of crop yield estimation, a time-series of hyperspectral airborne images with high spatial resolution (1 m) of a cotton field, which is located in San Joaquin Valley, California US, were acquired and classified by using object-oriented segmentation, then yield predicting models were built, and the accuracy and stability of yield models were validated with determining coefficients R2 and the root mean square error (RMSE). Results are as follows: (1) object-oriented SSMZ delineating method combines spectral, spatial and temporal information, reduces noises in images and yield data, improves the accuracy of yield prediction; (2) for same SSMZ number, first derivative predicting model is more accurate; (3) for same spectral input, models with fewer SSMZs show higher accuracy, which is due to spatial errors of airborne images and yield data. The results will improve monitoring methods for crop growth and yield while accelerate the application of UAV remote sensing in precision agriculture.

17.
BMC Cancer ; 15: 348, 2015 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-25934006

RESUMO

BACKGROUND: The aim of this study was to evaluate the clinical efficacy of postoperative radiotherapy (PORT), administered using three-dimensional conformal radiotherapy (3D-CRT) and our institutional standard clinical target volume (CTV) delineation, for completely resected stage IIIA(N2) non-small cell lung cancer (NSCLC). METHODS: From 2005 to 2012, consecutive patients with pT1-3N2 NSCLC who were treated with PORT employing our institutional CTV delineation after complete surgery or who underwent complete resection in our hospital but without PORT were identified. We excluded patients who had received neoadjuvant chemotherapy or radiation therapy (RT). Kaplan-Meier estimates for locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were performed. In the OS estimation, patients who received epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) during follow-up were censored at the time of TKI initiation. RESULTS: Data from 70 patients in the PORT group and 287 in the non-PORT group were analysed. All 70 cases received 3D-CRT following our institutional CTV guideline, with a median total dose of 50.4 Gy at 1.8 Gy/fraction. At a median follow-up of 34.3 months for the PORT group and 31.2 months for the non-PORT group, PORT significantly improved local control (5-yr LRFS 91.9% for PORT vs 66.4% for non-PORT, P < 0.001) and OS (5-yr OS 57.5% for PORT vs 35.1% for non-PORT, P = 0.003), whereas no differences in DMFS were noted (P = 0.18). In multivariable analyses, PORT was independently associated with an improved LRFS (HR 0.2, P = 0.001) and OS (HR 0.4, P = 0.001). All patients completed the planned RT dose without interruption of RT due to treatment-related complications. CONCLUSIONS: Our data suggested that PORT administered using the 3D-CRT technique following our institutional CTV delineation guideline resulted in a promising outcome with favourable survival for completely resected IIIA(N2) NSCLC, after controlling for subsequent EGFR-TKI confounding in the OS analysis. Prospective trials are needed to further corroborate these results.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaios Clínicos Fase III como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Período Pós-Operatório , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Radioterapia Conformacional , Estudos Retrospectivos , Resultado do Tratamento
18.
AJR Am J Roentgenol ; 204(2): 330-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25615755

RESUMO

OBJECTIVE. The purpose of this study was to determine an optimal multiparametric MRI protocol for characterizing tumors of low versus high grade and differentiating tumors as T1 versus T2 for preoperative staging of bladder urothelial carcinoma. SUBJECTS AND METHODS. Thirty-nine patients underwent MRI within 1 week before surgery. Three image sets-T2-weighted plus diffusion-weighted MRI (DWI), T2-weighted plus dynamic contrast-enhanced MRI (DCE-MRI), and T2-weighted plus DCEMRI plus DWI-were independently interpreted by two readers at 2-week intervals. ROC curves were plotted for both readers to compare the diagnostic efficacy of the three sets for detrusor muscle invasion for each reader, and the areas under the ROC curve were compared by use of the Bonferroni test. The apparent diffusion coefficient (ADC) values were correlated with histopathologic grade. RESULTS. A total of 49 category T1 and T2 lesions were analyzed. The average ADC of 11 low-grade tumors (1.141 ± 0.164 × 10(-3) mm(2)/s) was significantly (p < 0.05) higher than that of 20 high-grade malignant tumors (0.766 ± 0.091 × 10(-3) mm(2)/s). Neither reader considered T1 tumors as probably having muscle invasion (category T2) in the T2-weighted plus DWI image sets or the T2-weighted plus DWI plus DCE-MRI image sets. Using the T2-weighted plus DCE-MRI sets, the two readers overstaged 13 and 15 of 36 tumors by misdiagnosing category T1 as T2. With the cutoff ADC value of 0.899 × 10-3 mm(2)/s, the sensitivity and specificity for differentiating high- and low-grade bladder urothelial carcinoma were 100% and 95%. CONCLUSION. Multiparametric MRI with T2-weighted plus DWI plus DCE technique is the optimal protocol for preoperative staging of organ-confined bladder urothelial carcinoma. The ADC of low-grade tumors is significantly higher than that of high-grade tumors with 100% sensitivity and 95% specificity at a cutoff ADC value of 0.899 mm(2)/s.


Assuntos
Carcinoma de Células de Transição/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Sensibilidade e Especificidade
19.
Bioprocess Biosyst Eng ; 38(2): 399-405, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25218329

RESUMO

This study aimed to improve the production of polysaccharide by engineering the biosynthetic pathway in Ganoderma lucidum through the overexpression of α-phosphoglucomutase (PGM) gene. PGM is responsible for the linkage between sugar catabolism and sugar anabolism. The effects of PGM gene overexpression on intracellular polysaccharide (IPS) content, extracellular polysaccharide (EPS) production and transcription levels of three genes encoding the enzymes involved in polysaccharide biosynthesis, including PGM, UDP-glucose pyrophosphorylase (UGP), and ß-1,3-glucan synthase (GLS), were investigated. The maximum IPS content and EPS production in G. lucidum overexpressing the PGM gene were 23.67 mg/100 mg dry weight and 1.76 g/L, respectively, which were higher by 40.5 and 44.3% than those of the wild-type strain. The transcription levels of PGM, UGP and GLS were upregulated by 4.77-, 1.51- and 1.53-fold, respectively, in the engineered strain, suggesting that increased polysaccharide biosynthesis may result from a higher expression of those genes.


Assuntos
Reatores Biológicos/microbiologia , Genes Sintéticos/genética , Melhoramento Genético/métodos , Fosfoglucomutase/fisiologia , Polissacarídeos/biossíntese , Reishi/fisiologia , Recombinação Homóloga/genética , Polissacarídeos/genética , Polissacarídeos/isolamento & purificação , Regulação para Cima/genética
20.
Korean J Physiol Pharmacol ; 19(5): 427-34, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26330755

RESUMO

Significant evidence supports the role of the vestibular system in the regulation of blood pressure during postural movements. In the present study, the role of the vestibulo-spino-adrenal (VSA) axis in the modulation of blood pressure via the vestibulosympathetic reflex was clarified by immunohistochemical and enzyme immunoassay methods in conscious rats with sinoaortic denervation. Expression of c-Fos protein in the intermediolateral cell column of the middle thoracic spinal regions and blood epinephrine levels were investigated, following microinjection of glutamate receptor agonists or antagonists into the medial vestibular nucleus (MVN) and/or sodium nitroprusside (SNP)-induced hypotension. Both microinjection of glutamate receptor agonists (NMDA and AMPA) into the MVN or rostral ventrolateral medullary nucleus (RVLM) and SNP-induced hypotension led to increased number of c-Fos positive neurons in the intermediolateral cell column of the middle thoracic spinal regions and increased blood epinephrine levels. Pretreatment with microinjection of glutamate receptor antagonists (MK-801 and CNQX) into the MVN or RVLM prevented the increased number of c-Fos positive neurons resulting from SNP-induced hypotension, and reversed the increased blood epinephrine levels. These results indicate that the VSA axis may be a key component of the pathway used by the vestibulosympathetic reflex to maintain blood pressure during postural movements.

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