[Characteristics of acidification and the distribution of available phosphorus along soil depths in heavy clay soils in southern Henan Province, China]. / è±«å—é»æ¿åœŸå£¤åˆ†å±‚é ¸åŒ–å’Œè€•å±‚é€Ÿæ•ˆç£·åˆ†å¸ƒç‰¹å¾.

The acidification of agricultural soil in the southern part of the North China Plain has become more obvious, which is particularly true for the heavy clay soil types, such as yellow-cinnamon and lime concretion black soils. To understand the spatial variability of the pH value and nutrients on the vertical agricultural soil profile of heavy clay soils in this area, we measured pH values and available phosphorus (AP) in 63 farmland sample points from Xiping County in the southern Henan Province. Geostatistical methods and ArcGIS technology were used to map soil pH values along three soil depths (0-10, 10-20, and 20-30 cm) and the spatial distribution of soil AP in the tillage layer (0-20 cm). Furthermore, the correlation between pH and AP was analyzed. The results showed that mean pH values of typical yellow-cinnamon and typical fluvo-aquic soils from three soil layers were 4.98, 4.93, 5.31, and 5.46, 5.81, 6.26, respectively, which gradually increased with soil depths. However, there was no significant difference among the three soil layers. Mean pH values of typical lime concretion black soil from the three soil layers were 5.23, 5.43 and 6.03, respectively, and that of the 20-30 cm soil layer was significantly higher than that of the 0-10 cm (by 0.8-1 pH unit) and the 10-20 cm layers. The pH of the 20-30 cm soil layer of the calcareous lime concretion black and moist soils were also significantly higher than that of the 0-10 and 10-20 cm soil layers. The AP contents of the typical yellow-cinnamon, typical lime concretion black, moist, typical fluvo-aquic and calcareous lime concretion black soils in 0-20 cm soil layer were 8.85-54.75, 4.27-37.49, 8.22-51.80, 6.07-34.82, and 13.22-22.85 mg·kg-1, respectively. The results of the map indicated that the areas with low AP were distributed in the middle of the study area in blocks, and the areas with high AP were distributed around the study area in dots and flakes. The pH values of the typical yellow-cinnamon, typical lime concretion black, and moist soils positively correlated with the content of AP in the 0-20 cm soil layer. In conclusion, the heavy clay soil in southern Henan Province became stratified acidification, which slowed down along the soil depth. Soil AP contents in the tillage layer were distributed unevenly in the study area, and were affected by soil types and soil pH. These results would be useful for the improvement of heavy clay soil acidification in the southern part of the North China Plain.

Limb-bud and heart as a novel biomarker for gastric intestinal type adenocarcinoma.

The present study compared the expression levels of limb-bud and heart (LBH) between gastric intestinal-type adenocarcinoma (GITA) and healthy gastric tissues; with the aim of investigating the possible effect of LBH on the prognosis of patients with GITA and to analyze the associated signaling pathways in GITA. Three Oncomine gastric datasets were utilized for the preliminary prediction of the expression levels of LBH mRNA in GITA and healthy gastric tissues. Gene expression and corresponding clinical data of 163 patients with GITA were downloaded from The Cancer Genome Atlas. Wilcoxon signed rank-sum test was used to distinguish the clinical value of LBH expression in the various clinicopathological features. Subsequently, Kaplan-Meier univariate and Cox multivariate survival analyses were performed to determine the prognostic significance of LBH expression in patients with GITA. Function enrichment analysis was conducted for the co-expression gene of LBH, defined as correlation coefficient r>0.06 and P<0.05 using Pearson's χ2 test. Bioinformatics data demonstrated that compared with that in the normal gastric mucosa, LBH mRNA expression was dramatically higher in GITA tissues (P<0.05). There were significant relationships between the differential expression levels of LBH and clinicopathological parameters in GITA patients (all p<0.05), including pathological stage T (T3-4 vs. T1-2), lymph node metastasis (no vs. yes), distant metastasis (no vs. yes), histological grade (grade 3 vs. grades 1-2) and tumor stage (stages 3-4 vs. stages 1-2). Additionally, the overall survival and disease-free survival (DFS) of patients in the high expression group were poorer compared with those in the low expression group (P<0.05). Cox multivariate survival analysis indicated that increased LBH expression was an independent predictor of poor DFS prognosis in patients with GITA (P=0.045). In summary, LBH is highly expressed in GITA, which can be used as an independent predictor of poor prognosis in patients with GITA. LBH co-expressed genes are closely associated with GITA tumor migration and metastasis.

Antibacterial Diphenyl Ether, Benzophenone and Xanthone Derivatives from Aspergillus flavipes.

The extract of the strain Aspergillus flavipes DL-11 exerted antibacterial activities against six Gram-positive bacteria. During the following bioassay-guided separation, ten diphenyl ethers (1-10), two benzophenones (11-12), together with two xanthones (13-14) were isolated. Among them, 4'-chloroasterric acid (1) was a new chlorinated diphenyl ether. Their structures were elucidated by extensive spectroscopic data analysis, including IR, HR-ESI-MS, NMR experiments, and by comparison with the literature data. All compounds showed moderate to strong antibacterial effects on different Gram-positive bacteria with MIC values that ranged from 3.13 to 50 µg/mL, but none of the compounds exhibited activity against Gram-negative bacteria Vibrio parahaemolyticus ATCC17802 (MIC>100 µg/mL). In particular, the MICs of some compounds are at the level of positive control.

Early detection of enamel demineralization by optical coherence tomography.

Enamel is the outermost layer of the tooth that protects it from invasion. In general, an acidic environment accelerates tooth demineralization, leading to the formation of cavities. Scanning electron microscopy (SEM) is conventionally used as an in vitro tool for the observation of tooth morphology changes with acid attacks. Yet, SEM has intrinsic limitations for the potential application of in vivo detection in the early demineralization process. In this study, a high-resolution optical coherence tomography (OCT) system with the axial and transverse resolutions of 2.0 and 2.7 µm in teeth has been utilized for characterizing the effect of the acidic environment (simulated by phosphoric acid) on the enamel topology. The scattering coefficient and the surface roughness of enamel can be directly derived from the OCT results, enabling a quantitative evaluation of the topology changes with demineralization. The dynamic process induced by the acid application is also recorded and analyzed with OCT, depicting the evolution of the demineralization process on enamel. Notably, the estimated enamel scattering coefficient and surface roughness significantly increase with the application time of acid and the results illustrate that the values of both parameters after demineralization are significantly larger than those obtained before the demineralization, illustrating both parameters could be effective to differentiate the healthy and demineralized teeth and determine the severity. The obtained results unambiguously illustrate that demineralization of the tooth surface can be successfully detected by OCT and further used as an indicator of early-stage cavity formation.

Cytotoxic abietane and kaurane diterpenoids from Celastrus orbiculatus.

Celastrus orbiculatus is a medicinal plant belonging to the Celastraceae family. In this survey on the secondary metabolites of plants for obtaining antitumor substances, the chemical constituents of the stems of C. orbiculatus were investigated. Nortriptonoterpene (1), a new C19-norabietane diterpenoid, together with six other known abietane-type diterpenoids (2-7) and five known kaurane-type diterpenoids (8-12) were isolated and identified from the EtOAc extract of C. orbiculatus. Their structures were elucidated on the basis of extensive spectroscopic methods, including UV, IR, HR-ESI-MS, ECD, and NMR experiments, and by comparison with literature data. Compound 1 is a new C19-norabietane diterpenoid with 19 carbons. All compounds except for 10 and 11 were isolated from C. orbiculatus for the first time. The NMR data of 9 were reported for the first time. Compounds 1, 7 and 11 showed cytotoxicities against SGC-7901 with IC50 values of 63.2, 80.9 and 56.7 µM, respectively.

Effect of Apatinib on Serum CD4+CD25+ T cells, NK Cells, and T Cells Subgroup in Malignant Tumor.

OBJECTIVE: The immune makers including CD4+CD25+ T cells, natural killer cells, and T cells subgroup were retrospectively analyzed to find the relationship between apatinib and the immune system in the patients treated with apatinib. METHOD: Forty-two patients with advanced malignant tumors orally took apatinib as treatment and 16 patients with the same situation did not take apatinib as a control group. These patients were all included in the study, and they orally received apatinib 500 mg daily as monotherapy or combination. The treatment was continued until disease progression or intolerable toxicity. CD4+CD25+ T cells, natural killer cells, and T cells subgroup were detected before and 1 month after therapy for all the patients. The relationship between the changing number of immune cells and progression-free survival was analyzed in this study. RESULT: For the apatinib group, the rate of CD4+CD25+ T cells significantly increased (P = .048). The median progression-free survival was 3.25 months for the 42 patients. The median progression-free survival in the patients with the rate of CD4+CD25+ T cells increased and decreased was 5.8 months and 2.9 months, respectively (P = .012). Multivariate analysis found the increased rate of CD4+CD25+ T cells was an independent prognostic factor for a longer progression-free survival. The rate of natural killer cells and T cells subgroup did not change much after apatinib therapy, and they were not independent prognostic factors for progression-free survival. CONCLUSION: The rate of CD4+CD25+ T cells is very important in patients with apatinib treatment. The changing number of CD4+CD25+ T cells may be a good indicator for apatinib prognosis. Natural killer cells and T cells subgroup did not change much after apatinib, and they were not independent prognostic factors for progression-free survival.

In vivo detection of UV-induced acute skin effects using optical coherence tomography.

Ultraviolet (UV) rays have been identified as a carcinogen with long-term irradiation and are an important risk factor for skin cancer. Here, we report the use of optical coherence tomography/optical coherence tomography angiography (OCT/OCTA) to study acute UV-induced effects on skin in vivo. To understand the relationship between the acute effects and irradiated UV power density, three groups were irradiated with different power densities in our experiments. Furthermore, the same skin area was repeatedly scanned with OCT during UV irradiation to investigate the progress of the induced acute effects and after irradiation for observation of skin recovery. Subsequently, the OCT/OCTA results were quantitatively analyzed to acquire skin thickness and blood-vessel density for comparison. UV-induced acute effects on morphology and microcirculation can be identified from OCT/OCTA results, which showed the increases in the skin thickness and blood-vessel density and even severe damage types such as blisters. The results of quantitative analyses also illustrated that the severity of damage induced by UV irradiation can be distinguished and the skin recovery can be monitored with OCT. Our results indicate that OCT can be a promising tool for early detection of UV-induced acute skin damage.

PH-sensitive Dioctadecylamine-501 polymeric micelles for delivery of insulin.

In this work, fluorescently labeled smart micelle copolymers which consist of Dioctadecylamine-501 (DODA-501) as the hydrophobic segment, N-isopropylacrylamide (NIPAAm) as well as acrylic acid (AAc) as the hydrophilic segments were prepared. These micelles showed both thermo- and pH-sensitive properties due to the nature properties of NIPAAm and AAc, respectively. The particle size of the prepared micelles ranged from 94 approximately 200 nm and was found to increase with DODA-501 concentration. The size of particles varied in different pH mediums or different temperatures suggesting these micelles were pH- and thermo-sensitive. The image of confocal laser scanning microscopy (CLSM) illustrates these micelles had the ability to encapsulate rhodamine solution. From CLSM observation, fluorescein isothiocyanate (FITC) expression was found on the surface of micelles indicating the target detecting ability of these micelles. In drug loading and release studies, these micelles had the ability to encapsulate insulin and its release was pH sensitive, being more rapid under intestinal fluid environment, but resisting the drug release at gastric fluid environment. Stability test indicates these micelles had good stability during storage. These results suggest the pH-sensitivity of the DODA-501 polymeric micelles may be an interesting candidate for oral drug delivery system.

[Spectral properties of 2-(2'-hydroxyphenyl) benzimidazole].

2-(2'-hydroxyphenyl) benzimidazole (HBI) is one kind of organic molecule with excited-state proton transfer (ESPT) effect. The absorption spectra of HBI were observed in toluene, the mixture of toluene and ethanol, and ethanol, respectively. It was found that the absorption spectra in the three solvents are similar. The fluorescence of HBI was observed under the excitation of 317 nm light. Only one fluorescence band with a peak wavelength of 470 nm was observed in the toluene. There appeared two fluorescence bands in the mixed solvents and ethanol, of which the peak wavelength was 370 and 450 nm, respectively. Based on the ESPT theory, the fluorescence band with a peak at 370 nm is attributed to the emission from enol form of HBI molecule, while the band with a peak at 470 nm is attributed to the emission from tautomer form (i. e. keto form) via ESPT process. Because of the strong polarity of ethanol, the intermolecular H-bond can be formed between the HBI molecules and the ethanol and HBI molecules tend to exist in the solvated form. When HBI molecules in solvated form were excited, the zwitterionic form of HBI was formed via ESPT and returned to the ground state accompanied with fluorescence emission, so the fluorescence band with a peak at 450 nm is attributed to the zwitterionic emission of HBI. When the HBI in the three kinds of solvents was excited by the picosecond laser pulse at 532 nm, the two-photon induced fluorescence was not observed in the nonpolar solvents but observed in the polar solvents, which indicate that two-photon effect occurred in solvated form.

[Spectroscopic investigation of 3-hydroxyflavone in different polarity and pH values solutions].

The absorption and fluorescence spectra of 3-hydroxyflavone (3-HF) in different polar solvents were observed with UV-Vis spectrometer and fluorescence spectrometer, respectively. There are three absorption bands in the absorption spectra, wherein two absorption bands with absorption peak at 300 and 345 nm, respectively, are strong, and the other one with absorption peak at 415 nm is weak When the samples in different polar solvents were excited by 345 nm light, there appeared two new fluorescence bands peaked at 400 and 526 nm, respectively. The fluorescence band at 400 nm is attributable to the emission from enol structure and its intensity increases with increasing the polarity of protic solvents; that at 526 nm is attributable to the emission from the isomer structure and its intensity decreases with increasing the polarity of protic solvents. The results show that the increase in the polarity of protic solvents prevents the formation of isomer. When the samples in different polar solvents were excited by 415 nm light, three new fluorescence bands peaked at 440, 471 and 515 nm have not been reported so far. In order to identify the three new fluorescence bands, we prepared the samples with pH value of 5.0, 4.0 and 3.0 through incorporating the different amounts of acetic acid into 3-HF solution. The fluorescence spectra in different pH value solution were observed under excitation of 415 nm light, and it was found that the intensity of two fluorescence bands in the region of shorter wavelength changes with pH values changing. For identifying the fluorescence band of 515 nm peak wavelength, we put sodium hydroxide into 3-HF in ethanol solution and prepared 3-HF samples with pH values of 8.0, 8.5, 9.0, and 10.0. When the samples were excited by the 415 nm light, it was found that two fluorescence bands in the region of shorter wavelength disappeared and the intensity of the fluorescence band of 515 nm was enhanced. Since in sodium hydroxide solution 3-HF forms anion easily, we ascribed the fluorescence band with 515 nm peak wavelength to the emission from the 3-HF anion.

[The spectra properties of 2-(2'-hydroxyphenyl)benzothiazole in different solvents].

2-(2 -hydroxyphenyl)benzothiazole (HBT) is a typical compound with excited--state intramolecular proton transfer (ESIPT) effect. The mechanism of the influence of the solvent polarity on the ESIPT effect of HBT was investigated by means of absorption and fluorescence spectra in different polar solvents. The absorption spectra of HBT molecule in all solvents have the similar configuration and are mainly situated in the UV region from 260 to 370 nm. The absorption peaks are located at 287 and 335 nm and have the decline trend with the increase in the solvent polarity. In addition, there is a very weak absorption band at 400 nm and it is attributable to the absorption from the keto form of HBT. Under UV excitation at 335 nm, the fluorescence spectra in all the solvents were obtained. All the fluorescence spectra exhibit dual fluorescence peaks, which are located at 385 and 512 nm respectively. The former is attributed to the emission from the HBT enol forms, named the normal fluorescence, and the latter the emission from the keto tautomer emission, named ESIPT fluorescence. The fluorescence spectra of HBT show that the intensity of the normal fluorescence is obviously increased and the intensity of the ESIPT fluorescence is decreased with enhancing the polarity of the solvents. This indicates that the strong polar solvents are not favorable to the ESIPT of HBT. Because the solvated enols in the polar solvent prevent the ESIPT from happening, the ESIPT efficiency of HBT in cyclohexane is the largest and that of HBT in ethanol is the smallest. The three fluorescence bands of HBT in different polarity solvents were observed with 400 nm excitation. One fluorescence band at ca. 510 nm is referred to as the ESIPT fluorescence. This confirms that the weak absorption at 400 nm results from the keto tautomer and the enol and keto forms can coexist under the normal condition, but the enol form is the absolutely predominant. In addition, the other two unknown fluorescent emission bands appear at 436 and 456 nm respectively. Their possible origin is the emission from the deprotonated anion of HBT keto tautomer.

[Study on the fluorescence spectra of 7-hydroxyquinoline in dimethyl sulfoxide solution].

7-hydroxyquinoline (7-HQ) is a kind of organic molecule with excited-state proton transfer (ESPT) effect. 7-HQ in ethanol solution causes ESPT reaction under the excitation of ultraviolet light. The fluorescence spectrum of the sample exhibits two bands. In contrast, 7-HQ in dimethyl sulfoxide (DMS) solution does not cause ESPT reaction. The fluorescence spectrum of the sample exhibits a single band. But after the sample was irradiated with a strong UV light, its fluorescence spectrum also exhibits two bands. This phenomenon is reported for the first time in the present paper, and its cause is investigated through the study on the absorption spectra and fluorescence spectra of 7-HQ in ethanol, dimethyl sulfoxide and N, N-dimethyl formamide solution. The conclusion is that the change in the fluorescence spectrum of 7-HQ in DMS solution is due to the fact that 7-HQ causes ESPT reaction which results from the photodecomposition of DMS and the product of water after the solution was irradiated with strong UV light.