Evaluation of retinal and choroidal changes in patients with Alzheimer’s type dementia using optical coherence tomography angiography

AIM: To evaluate the changes in fundus parameters in patients with Alzheimer’s type dementia (ATD) using optical coherence tomography angiography (OCTA), to record flash electroretinograms (ERG) using the RETeval system and to explore changes in retinal function. METHODS: Twenty-nine patients with ATD and 26 age-matched normal subjects were enrolled. All subjects underwent OCTA scans to analyse the superficial retinal vessel parameters in the macular area, including the vessel length density, the vessel perfusion density and the area of foveal avascular zone (FAZ), as well as the choroidal thickness. The differences between the patients with ATD and the normal control group were compared and explored the relevant factors affecting vessel parameters. We also recorded the flash ERGs using the RETeval system and intended to explore changes in retinal function by analysing the ERG image amplitude in patients with ATD. RESULTS: The vessel parameters [Pvessel length density=0.005 and Pvessel perfusion density=0.006) and average choroid thickness (P<0.001) in the macular area of the ATD group was less than the control group. The FAZ area was statistically significantly enlarged in the ATD group (P<0.001). These parameters were correlated with the Mini-Mental State Examination (MMSE) score and the Montreal Cognitive Assessment (MoCA). CONCLUSION: Patients with ATD exhibit decreases in the parameters associated with fundus. In addition, these indicators significantly correlate with the MMSE score and the MoCA score. OCTA may be an adjunct tool with strong potential to track changes in the diagnosis and monitoring the progression of the disease.     

Organic–inorganic hybrid coating materials derived from renewable soybean oil and amino silanes

Novel organic–inorganic hybrid coating materials were developed using amino silanes and acetoacetylated soybean oil. The acetoacetylated soybean oil was prepared from soybean oil (a renewable resource) using a solvent-free method involving a thiol–ene and transesterification reactions, and the chemical structure was characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) spectroscopy, and viscosity analyses. On the basis of the acetoacetylated soybean oil, several organic–inorganic hybrid coating materials were prepared using different amino silanes by a catalyst-free method involving one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique), and their crosslinked structures were determined from their FT-IR and solid-state ²⁹Si NMR spectra. The resulting coating materials have good mechanical/chemical performance. This method for preparing renewable organic–inorganic hybrid coating materials may have wide uses because plant oils contain many unsaturated C C bonds and easy access to acetoacetate functional groups.

A novel coating material was synthesized in one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique).     

Stability studies of ZnO and AlN thin film acoustic wave devices in acid and alkali harsh environments

Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications. However, for many of these applications, the SAW devices will inevitably be used in acid or alkali harsh environments, which may cause their early failures. In this work, we investigated the behavior and degradation mechanisms of thin film based SAW devices in acid and alkali harsh environments. Results show that under the acid and alkali attacks, chemical reaction and corrosion of ZnO devices are very fast (usually within 45 s). During the corrosion, the crystalline orientation of the ZnO film is not changed, but its grain defects are significantly increased and the grain sizes are decreased. The velocity of ZnO-based SAW devices is decreased due to the formation of porous structures induced by the chemical reactions. Whereas an AlN thin-film based SAW device does not perform well in acid–alkali conditions, it might be able to maintain a normal performance without obvious degradation for more than ten hours in acid or alkali solutions. This work could provide guidance for the applications of both ZnO or AlN-based SAW devices in acid/alkali harsh environments.

Surface acoustic wave (SAW) devices based on piezoelectric thin-films such as ZnO and AlN are widely used in sensing, microfluidics and lab-on-a-chip applications.     

Elucidation of the electron energy structure of TiO2(B) and anatase photocatalysts through analysis of electron trap density

A clear understanding of the electron energy structure of TiO₂(B)/anatase is needed to study the related catalytic reactions and design new composite photocatalysts. In this study, the electron energy structures of TiO₂(B) and anatase were estimated by analyzing the energy-resolved distribution of electron traps measured by reversed double-beam photoacoustic spectroscopy. In the mixture of TiO₂(B) and anatase, interfacial charge-transfer excitation from anatase to electron traps of TiO₂(B) was suggested. By analyzing this for TiO₂(B), the electron level with a relatively high density of states was found to be located ∼0.07 eV deeper than that for anatase. Furthermore, a similar electron energy structure was suggested for a composite photocatalyst having a mixed phase of TiO₂(B) and anatase.

The electron energy structures of TiO₂(B) and anatase were estimated by analyzing the energy-resolved distribution of electron traps.     

Isolation of antioxidant peptides from yak casein hydrolysate

Enzymatic hydrolysis of protein is a principal method to obtain antioxidant peptides. A yak casein hydrolysate (YCH) was prepared by alcalase and trypsin digestion. An ultrafiltration membrane system was used to divide the hydrolysate into four molecular weight fractions; YCH-4 (<3 kDa) had the highest antioxidant activity. Fraction YCH-4 was separated into six subfractions by gel filtration chromatography; reverse-phase high performance liquid chromatography (RP-HPLC) was then used to partition sixteen antioxidant peptide subfractions. Liquid chromatography/electrospray tandem mass spectrometry (LC-ESI-MS/MS) was used to determine the amino acid sequence of a purified antioxidant peptide to be Arg-Glu-Leu-Glu-Glu-Leu (787.41 Da). Finally, a synthetic Arg-Glu-Leu-Glu-Glu-Leu peptide was evaluated for its superoxide anion and hydroxyl radical scavenging activity (IC₅₀ = 0.52 and 0.69 mg mL⁻¹), which confirmed the activity of the native purified peptide. Our results suggested that isolation and purification of antioxidant peptides from yak casein could be an important means to obtain natural antioxidant peptides.

Enzymatic hydrolysis of protein is a principal method to obtain antioxidant peptides.     

Ultrafast broadband nonlinear optical properties and excited-state dynamics of two bis-chalcone derivatives

The development of organic nonlinear optical (NLO) chromophores is vital for various fields such as two-photon biomedical imaging, optical limiting, etc. In this work, two bis-chalcone molecules 1,4-bis[3-(2,4-dimethoxyphenyl)-2-acryloyl]benzene (C1) and 4,4′-bis[3-(2,4-bimethoxy phenyl)-2-acryloyl]biphenyl (C2) were synthesized and characterized. The excited-state dynamics of these two chromophores were studied using femtosecond transient absorption (TA) measurements. And their broadband nonlinear absorption properties and optical limiting (OL) response were investigated by femtosecond open-aperture Z-scan and intensity-dependent transmittance measurements in the wavelength range from 515 nm to 800 nm, respectively. The TA results demonstrate that C2 has strong excited-state absorption behavior and longer lifetime. In addition, the nonlinear absorption response of C2 was found to be superior to that of C1 in the visible range after 500 nm, which is attributed to a two-photon-absorption induced excited-state absorption mechanism. These results indicate that the nonlinear optical response and excited-state dynamics in bis-chalcone compounds could be enhanced via intramolecular charge-transfer.

The introduction of a benzene ring largely affects the excited-state absorption spectra and dynamics of these chromophores.     

Catalytic oxidation of NO over MnOx–CoOx/TiO2 in the presence of a low ratio of O3/NO: activity and mechanism

In order to broaden the temperature range of NO oxidation reaction in flue gas and maintain high oxidation efficiency, various loading amounts of MnO_x–CoO_x/TiO₂ mesoporous catalysts were tested in the catalytic oxidation of NO. It was found that 15%MnO_x–CoO_x(2 : 1)/TiO₂ demonstrated the best adsorption performance to oxygen species and contained more oxygen vacancies, as well as the best surface oxygen mobility, thus exhibiting excellent NO catalytic oxidation activity. O₃ (O₃/NO < 1) combined with 15%MnO_x–CoO_x(2 : 1)/TiO₂ improved the oxidation efficiency of NO at 50–400 °C, especially below 250 °C. When the temperatures were less than 250 °C, the oxidation efficiencies of NO by O₃ over 15%MnO_x–CoO_x(2 : 1)/TiO₂ were 5–13% higher than the calculated theoretical efficiencies. This indicated that there was a synergistic effect between O₃ and 15%MnO_x–CoO_x(2 : 1)/TiO₂ below 250 °C. Based on the results of in situ DRIFTS studies, it was deduced that monodentate nitrates were the main intermediates that produced a synergistic effect due to the introduction of O₃. In addition, O₃ accelerated the transformation between nitrate species, decreased the decomposition temperature of nitrate species, and inhibited the accumulation of nitrate ions, thus improving the oxidation efficiency of NO.

O₃ promotes the formation of monodentate nitrates at low temperature, thus improving the efficiency of NO oxidation.     

Diagnosis of female urethral diverticulum using transvaginal contrast-enhanced sonourethrography

Introduction and hypothesis

This study investigated the value of transvaginal contrast-enhanced sonourethrography for the diagnosis of female urethral diverticulum (UD) by comparing results of contrast-enhanced ultrasound images and surgical findings.

Methods

A total of 14 female UD patients underwent preoperative transvaginal contrast-enhanced sonourethrography between July 2010 and June 2012. History and physical examination were initially assessed by the same urologist. Transvaginal contrast-enhanced ultrasound imaging was performed and interpreted by the same ultrasonographer. Definite diagnosis was made by tracking the flow of the microbubbles into the cyst. Additionally, sagittal, cross-sectional, and dynamic images were obtained, and color Doppler ultrasound was applied in all cases. Data on the size, location, configuration, and opening of the UD was documented, and then compared with the surgical findings.

Results

The most common symptoms presenting in the UD patients included urinary incontinence (71.5 %), recurrent urinary tract infection (57.1 %), frequency (50 %), urgency (35.7 %), dysuria (35.7 %), and dyspareunia (21.4 %). On physical examination, 8 out of 14 patients (57.1 %) had a palpable anterior vaginal wall mass, while 6 out of 14 patients (42.9 %) had no palpable mass. Transvaginal contrast-enhanced sonourethrography revealed 17 diverticula orifices in total and correlated well with surgical findings regarding the size, location, configuration, and the opening of the UD.

Conclusions

In patients with chronic irritative bladder symptoms, but with no response to conventional treatment a high index of suspicion for UD should be maintained. Our study demonstrates that transvaginal contrast-enhanced sonourethrography is a useful tool for defining the size, location, configuration, and opening of the UD before surgery.     

锡类散对肥皂液灌肠致兔肠黏膜损伤的保护作用

目的观察锡类散对肥皂液灌肠造成的兔肠黏膜损伤的保护作用。方法将40只家兔随机分成两组各20只,分别用肥皂液(A组)、肥皂液+锡类散(B组)灌肠。观测各组灌肠前后血钾水平变化以及粪便涂片肠黏膜细胞脱落情况;在腹腔麻醉下取直肠、结肠远心回、结肠近心回肠壁制作病理切片,电镜下观察肠黏膜细胞亚显微结构变化;光镜观察肠黏膜充血、水肿情况。结果A组灌肠后血钾水平显著低于B组(P<0.01)。两组直肠部位肠黏膜损伤最重,结肠远心回其次,结肠近心回最轻;A组直肠部位以及结肠远心回肠黏膜损伤程度较B组严重(均P<0.01)。A组可见肠黏膜细胞损伤较严重,线粒体、内质网肿胀,细胞连接增宽,见大量凋亡、坏死细胞。B组肠黏膜细胞亚显微结构基本无改变或轻度损伤,细胞质内细胞器丰富,结构未见异常,细胞连接紧密,固有层腺体结构正常。A组肠黏膜细胞脱落情况较B组严重。结论锡类散对碱性灌肠液造成的兔肠黏膜损伤具有一定保护作用。     

优质护理对婴幼儿雾化吸入治疗依从性及满意度的影响

目的 探讨优质护理对婴幼儿雾化吸入治疗依从性及家长满意度的影响.方法 将1206例雾化吸入治疗惠儿按时间段分为对照组(531例)和观察组(675例).对照组给予常规护理和健康教育;观察组在此基础上优化雾化室环境,改良雾化吸入治疗方式(诱导式治疗、吸入式治疗、睡眠式治疗),采取预约服务.结果 观察组雾化吸入治疗依从性和家长满意度显著优于对照组(均P＜0.01).结论 优质护理可增加婴幼儿在雾化吸入治疗中的舒适度,提高患儿治疗依从性,提高患儿家长的满意度.