Spectral reflectance in the near-infrared （NIR） shoulder （750-900 nm） region is affected by internal leaf structure, but it has rarely been investigated. In this study, a dehydration treatment and ...three paraquat herbicide applications were conducted to explore how spectral reflectance and shape in the NIR shoulder region responded to various stresses. A new spectral ratio index in the NIR shoulder region （NSRI）, defined by a simple ratio of reflectance at 890 nm to reflectance at 780 nm, was proposed for assessing leaf structure deterioration. Firstly, a wavelength-independent increase in spectral reflectance in the NIR shoulder region was observed from the mature leaves with slight dehydration. An increase in spectral slope in the NIR shoulder would be expected only when water stress developed sufficiently to cause severe leaf dehydration resulting in an alteration in cell structure. Secondly, the alteration of leaf cell structure caused by Paraquat herbicide applications resulted in a wavelength-dependent variation of spectral reflectance in the NIR shoulder region. The NSRI in the NIR shoulder region increased significantly under an herbicide application. Although the dehydration process also occurred with the herbicide injury, NSRI is more sensitive to herbicide injury than the water-related indices （water index and normalized difference water index） and normalized difference vegetation index. Finally, the sensitivity of NSRI to stripe rust in winter wheat was examined, yielding a determination coefficient of 0.61, which is more significant than normalized difference vegetation index （NDVI）, water index （WI） and normalized difference water index （NDWI）, with a determination coefficient of 0.45, 0.36 and 0.13, respectively. In this study, all experimental results demonstrated that NSRI will increase with internal leaf structure deterioration, and it is also a sensitive spectral index for herbicide injury or stripe rust in winter wheat.
To prepare and characterize polyelectrolyte multilayer film coated microbubbles for use as ultrasound contrast agent (UCA) and evaluate its effects in ultrasonic imaging on normal rabbit's liver ...parenchyma.
Perfluorocarbon (PFC)-containing microbubbles (ST68-PFC) were prepared by sonication based on surfactant (Span 60 and Tween 80). Subsequently, the resulting ST68-PFC microbubbles were coated using oppositely charged polyelectrolytes by microbubble-templated layer-by-layer self-assembly technique via electrostatic interaction. The enhancement effects in ultrasonic imaging on normal rabbit's liver parenchyma were assessed.
The obtained microbubbles exhibited a narrow size distribution. The polyelectrolytes were successfully assembled onto the surface of ST68-PFC microbubbles. In vivo experiment showed that polyelectrolyte multilayer film coated UCA effectively enhanced the imaging of rabbit's liver parenchyma.
The novel microbubbles UCA coated with polyelectrolyte multilayer, when enabled more function, has no obvious difference in enhancement effects compared with the pre-modified microbubbles. The polymers with chemically active groups (such as amino group and carboxyl group) can be used as the outermost layer for attachment of targeting ligands onto microbubbles, allowing selective targeting of the microbubbles to combine with desired sites.
Background： During craniotomies using the transpetrosal-presigmoid approach, exposure of the sigmoid sinus remains an essential but hazardous step. In such procedures, accurate localization of the ...anterosuperior point of the transverse-sigmoid sinus junction （ASTS） is very important lbr reducing surgical morbidity. This study aimed to create an accurate and practical method for identifying the ASTS. Methods： On the lateral surfaces of 40 adult skulls （ 19 male skulls and 21 female skulls）, a rectangular coordinate system was defined to measure the x and y coordinates of two points： the ASTS and the squamosal-parietomastoid suture junction （SP）. With the coordinate system, the distribution characteristics of the ASTS were statistically analyzed and the differences between the ASTS and SP were investigated. Results： For ASTS-x, significant differences were found in different sides （P =0.020）; the ASTS-x in male skulls was significantly higher on the right side （P =0.017）; there was no significant difference between the sides in female skulls. There were no significant differences in gender or interaction of gender and side for ASTS-x, and for ASTS-y, there were no significant differences in side, gender, or interaction of gender and side. For both sides combined, the mean ASTS-x was significantly higher than the mean SP-x （P = 0.003） and the mean ASTS-y was significantly higher than the mean SP-y （P = 0.011 ）. Conclusions： This reference coordinate system may be an accurate and practical method for identifying the ASTS during presigmoid craniotomy. The SP might be difficult to find during presigmoid craniotomy and, therefore, it is not always a reliable landmark for defining the ASTS.
Background Survivin, a member of the inhibitor of apoptosis protein （IAP） family, overexpresses in tumor cells and not expresses in terminally differentiated adult tissues. This study aimed to ...investigate the effects of survivin-specific siRNA on cell proliferation, apoptosis and chemosensitivity to cisplatin in vitro and in vivo and explore the mechanisms about decreasing expression of survivin in reversing cancer cells resistance to chemotherapeutic drug.Methods Survivin-specific siRNA was transfected into A549/DDP cells. The expression of survivin and lung resistance-related protein （LRP） mRNA levels were determined by RT-PCR, chemosensitivity of A549/DDP （cisplatin）cells to cisplatin was determined by MTT assay, and apoptosis and cell cycle were determined by flow cytometry （FCM）.The protein expression levels of survivin, LRP, cyclin-D1, caspase-3 and bcl-2 were determined by Western blotting analyses. The effect of survivin siRNA inhibition on tumor growth was studied in athymic nude mice in vivo.Results Survivin-specific siRNA efficiently down-regulated survivin expression. The cell cycle was arrested at G2/M phase, and apoptosis was obviously found. Inhibition of survivin expression could make the IC50 and drug-resistant index of cisplatin decrease, and enhance the cancer cells sensitivity to cisplatin. After transfection by survivin-specific siRNA, expression of LRP and cyclin-D1 were downregulated, caspase-3 expression was upregulated, bcl-2 expression had no obvious change. The animal experiment confirmed knockdown of survivin could inhibit the tumor growth.Conclusions Survivin-specific siRNA can efficiently suppress the expression of survivin, increase apoptosis, inhibit cells proliferation and enhance the chemosensitivity to cisplatin in vitro and in vivo. Suppression of survivin expression helping to reverse drug-resistance may have relationship with downregulation of LRP and upregulation of caspase-3.Anti-tumor strategies based on the inhibition of survivin may be useful in targeting lung adenocarcinomas.
Dear Editor Hair cells （HCs） clustered produce spontaneous spike n cochlear sensory epithelia and evoked action potentials during the developmental stage of auditory, which rely on many ion channels, ...such as Ca2＋ channels, K＋ channels and Na＋ channels （Housley et al., 2006; Marcotti et al., 2003）. As the dominant molecule acting in action potentials in most of excitable cells, Na＋ channels （VGSCs） were deemed to be indispensable in the spontaneous and evoked action po- tentials of HCs （Marcotti et al., 2003）.
In light of the scarcity of reports on the interaction between HSV-1 nucleocapsid protein UL25 and its host cell proteins,the purpose of this study is to use yeast two-hybrid screening to search for ...cellular proteins that can interact with the UL25 protein.C9orf69,a protein of unknown function was identified.The interaction between the two proteins under physiological conditions was also confirmed by biological experiments including co-localization by fluorescence and immunoprecipitation.A preliminary study of the function of C9orf69 showed that it promotes viral proliferation.Further studies showed that C9orf69 did not influence viral multiplication efficiency by transcriptional regulation of viral genes,but indirectly promoted proliferation via interaction with UL25.
Quality control can decrease variations in the performance of colonoscopists and improve the effectiveness of colonoscopy to prevent colorectal cancers. Unfortunately, routine quality control is ...difficult to carry out because a practical method is lacking. The aim of this study was to develop an automatic quality control system (AQCS) and assess whether it could improve polyp and adenoma detection in clinical practice.
First, we developed AQCS based on deep convolutional neural network models for timing of the withdrawal phase, supervising withdrawal stability, evaluating bowel preparation, and detecting colorectal polyps. Next, consecutive patients were prospectively randomized to undergo routine colonoscopies with or without the assistance of AQCS. The primary outcome of the study was the adenoma detection rate (ADR) in the AQCS and control groups.
A total of 659 patients were enrolled and randomized. A total of 308 and 315 patients were analyzed in the AQCS and control groups, respectively. AQCS significantly increased the ADR (0.289 vs 0.165, P < .001) and the mean number of adenomas per procedure (0.367 vs 0.178, P < .001) compared with the control group. A significant increase was also observed in the polyp detection rate (0.383 vs 0.254, P = .001) and the mean number of polyps detected per procedure (0.575 vs 0.305, P < .001). In addition, the withdrawal time (7.03 minutes vs 5.68 minutes, P < .001) and adequate bowel preparation rate (87.34% vs 80.63%, P = .023) were superior for the AQCS group.
AQCS could effectively improve the performance of colonoscopists during the withdrawal phase and significantly increase polyp and adenoma detection. (Clinical trial registration number: NCT03622281.)
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This paper studied the biofilm properties and corrosion behavior of sulfate reducing bacteria （SRB） on stainless steel 316L （SS316L） surface in circulating cooling water system with and without ...additives including hydroxy ethyl fork phosphonic acid （HEDP）, dodecyl dimethyl benzyl anunonium chlotide （1227） and NaClO. Biochemical technique, electrochemical technology, X-ray photoelectron spectroscopy （XPS） and scanning electron microscope （SEM） were used. The results show that the extracellular polymeric substance （EPS） in biofilm attached on the SS316L surface mainly contain proteins and polysaccharides, the contents are 98 ug.cm-2 and 635ug.cm-2, respectively. The polysaccharides were cut by 1227 about 80%, while 55% by NaCIO. The proteins were reduced by NaCIO about 53%, while only 30% by 1227. The potentiodynamic polarization shows that the corrosion potential of SS316L was enhanced from -0.495 V to -0.390 V by the chemical additive delaying the occurrence of the corrosion. And the corrosion rate was also reduced from 5.19 × 10^-3 mm·a^-1 to 2.42 × 10^-3 mm＇a . But NaCIO stdl caused pitting corrosion after stenhzmg the bacteria, while 1227 can form a protective film on the surface of SS316L. Though HEDP contribute to the bacteria activity, it can enhance the breakdown potential. XPS results confirmed that 1227 can change the value of C：O in the biofilm attached on metal surface, and NaCIO can eliminate the existence of amidogen. This study would provide some recommendations for the selection of chemical additives in the thermal power plant.
Although dynamic reactions of imines have been extensively studied, the dynamic behaviors manipulated by chirality remain nearly unexplored. In this work, enantioselective amine exchange reactions ...were demonstrated as a first example via the reaction of enantiomeric chiral amines such as natural amino acids with a series of innovative axially chiral 1,1′-binaphthyl-2,2′-diamine (BNDA)-based imines that were prepared from the condensation reactions between BNDA and salicylaldehyde (SA) or its derivatives. This enantioselective dynamic behavior can be directly indicated by the degree of the fluorescence response of the R-configuration of imines to the d-enantiomer of chiral amine, because the released BNDA can serve as the fluorescence signal output when the amine exchange reaction occurs, which is far higher than the response to its l-enantiomer under identical experimental conditions. For the S-configuration of chiral imines, the fluorescence response is the opposite. The enantioselective exchange reaction can be tuned by altering the electron-withdrawing or electron-donating capability of the substituent at position 4 or 5 of the SA part of chiral imines. Not only o-OH groups in SA-based imines but also protic solvents used as reaction media were found to be important to the dynamic behavior at high rates.
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