The sensing mechanism of a flavone-based ESIPT fluorescent chemodosimeter for selective recognition towards fluoride: a theoretical

The sensing mechanism of 3-hydroxyflavone-based (3-HF) fluorescent chemodosimeter 3-triisopropylsilylflavone (3-TPSF) for detecting fluoride (F⁻) has been theoretically investigated. The calculated Laplacian bond order confirms that the Si–O bond of 3-TPSF is the reaction site of F⁻. The free energy barrier of 18.33 kcal mol⁻¹ indicates that F-triggered desilylation reaction can occur and then form the anionic state of 3-HF (3-HF⁻) with a fluorescence peak at 545 nm. 3-HF⁻ captures H⁺ of the mixed aqueous medium to be transformed into 3-HF with an intramolecular hydrogen bond (O₁–H⋯O₂). The energy barrier of 1.86 kcal mol⁻¹ in the S₁ state obtained from the constructed potential energy curves confirms that the excited state intramolecular proton transfer (ESIPT) in 3-HF occurs to form a tautomer structure, which produces a long-wavelength emission of 549 nm. The fluorescence emitted from both 3-HF⁻ and 3-HF agrees with the experimental value of 530 nm appearing after adding F⁻. Charge transfer analyses indicate that the extent of intramolecular charge transfer in 3-HF⁻ is more intense than that of 3-TPSF, which induces a large Stokes shift of 180 nm. Therefore, the sensing mechanism is attributed to the combination of a large charge transfer feature and ESIPT that are caused by desilylation reaction. The significant fluorescence change makes 3-TPSF a chemodosimeter for detecting F⁻.

The sensing mechanism of 3-hydroxyflavone-based (3-HF) fluorescent chemodosimeter 3-triisopropylsilylflavone (3-TPSF) for detecting fluoride (F⁻) has been theoretically investigated.     

胰腺实性假乳头状肿瘤伴高级别转化一例

伴有高级别转化的胰腺实性假乳头状肿瘤相对罕见,该文报道1例33岁的女性病例,显微镜下肿瘤由囊性区、假乳头区和实性区构成,实性区可见大片出血坏死,假乳头区可见松散的上皮样细胞包绕纤维血管轴心,肿瘤细胞呈圆形和卵圆形,胞质丰富嗜酸性,核圆形,部分细胞异型性明显,并可见瘤巨细胞;免疫表型：肿瘤细胞转录因子E3（TFE3）阳性...     

The dynamic changes of plasma neuropeptide y and neurotensin and their role in regulating cerebral hemodynamics in neonatal hypoxic-ischemic encephalopathy

Hypoxic-ischemic encephalopathy (HIE) is a common cause of neonatal encephalopathy and is one of the most important causes of neonatal death and disabilities, especially those infants with moderate to severe encephalopathy. However, the pathogenesis of HIE still remains unclear. The purpose of this study was to explore the dynamic changes in plasma neuropeptide Y (NPY) and neurotensin (NT) as well as their role in regulating cerebral hemodynamics in HIE patients. The plasma levels of NPY and NT in the umbilical artery and peripheral blood on the first, third, and seventh days after birth in 40 term infants with HIE and 40 healthy controls were measured using radioimmunoassay. On the first day of life, the blood samples were collected immediately when ultrasound examinations were finished. The ultrasound transducer was placed on the temporal fontanelle to detect the hemodynamic parameters of the middle cerebral artery, including peak systolic flow velocity, end-diastolic flow velocity, time-average mean velocity, pulsatility index, and resistance index (RI) in both groups were measured by pulse Doppler ultrasound in the first day after birth. The relationship between RI and NPY or NT was analyzed by linear regression analysis. NPY levels in umbilical blood ([mean +/- standard deviation] 615.5 +/- 130.7 ng/L) and first-day peripheral blood (355.9 +/- 57.4 ng/L) in neonates with HIE were significantly higher than those in normal newborns' blood (199.1 +/- 63.2 and 214.4 +/- 58.0 ng/L, respectively; P < 0.01). NPY levels in HIE neonates then declined to control levels on the third day after birth ( P > 0.05). However, the levels of plasma NT in umbilical blood and peripheral blood were much higher in the HIE group than those in normal newborns during the first week ( P < 0.01). The results of Doppler ultrasound examinations showed that cerebral blood flow velocity significantly decreased, whereas RI increased markedly in HIE patients compared with healthy controls ( P < 0.01). Linear regression analysis revealed that the RI was positively correlated with NPY levels ( R = 0.614; P < 0.01) and negatively correlated with NT levels ( R = -0.579; P < 0.01). The results of this study showed that there was a significant increase in plasma NPY and NT levels in HIE patients and this was strongly related to the severity of HIE, and the hemodynamic parameter RI was significantly correlated with NPY and NT. Therefore, we believe that the dynamic changes in plasma NPY or NT levels participate in the mechanisms of HIE by regulating cerebral hemodynamic changes after neonatal asphyxia occurs.     

Research on Microstructure and Properties of AlSi10Mg Fabricated by Selective Laser Melting

In order to obtain high-performance aluminum alloy parts fabricated by selective laser melting, this paper investigates the relationship between the process parameters and microstructure properties of AlSi10Mg. The appropriate process parameters are obtained: the layer thickness is 0.03 mm, the laser power is 370 W, the scanning speed is 1454 mm/s, and the hatch spacing is 0.16 mm. With these process parameters, the ultimate tensile strength of the as-printed status is 500.7 ± 0.8 MPa, the yield strength is 311.5 ± 5.9 MPa, the elongation is 7.7 ± 0.5%, and the relative density is 99.94%. After annealing treatment at 275 °C for 2 h, the ultimate tensile strength is 310.8 ± 1.3 MPa, the yield strength is 198.0 ± 2.0 MPa, and the elongation is 13.7 ± 0.6%. The mechanical properties are mainly due to the high relative density, supersaturate solid solution, and fine dispersed Si. The supersaturate solid solution and nano-sized Si formed by the high cooling rate of SLM. After annealing treatment, the Si have been granulated and grown significantly. The ultimate tensile strength and yield strength are reduced, and the elongation is significantly improved.     

腹腔镜下子宫肌瘤剔除术对子宫肌瘤患者血清应激激素及炎症因子的影响

目的:探讨分析腹腔镜下子宫肌瘤剔除术对子宫肌瘤患者血清应激激素以及炎症因子的影响.方法:选取在某院行腹腔镜下子宫肌瘤剔除术治疗的56例子宫肌瘤患者作为观察组,选择同期行开腹术治疗的子宫肌瘤患者56例作为对照组,比较两组患者的炎症因子与应激激素水平.结果:治疗后,观察组患者TNF-α、IL-6、IL-8与CRP水平显著低...     

Cyclodextrin and its derivatives as effective excipients for amorphous ulipristal acetate systems

Many efforts have been devoted to screening new solid-state forms of poorly soluble drugs in the pharmaceutical industry, thus modulating the drug properties without changing the pharmacological nature. It is a wise strategy to prepare amorphous series with cyclodextrin (CD) and its derivatives as excipients to enhance the aqueous solubility, dissolution, and bioavailability of water-insoluble drugs. In this study, four binary amorphous mixtures of ulipristal acetate (UPA) with CDs (β-CD, γ-CD, dimethyl-β-CD, hydroxypropyl-β-CD) were prepared by the co-milling method and characterized in the solid-state. According to powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC), UPA existed in the noncrystalline form in the four binary amorphous mixtures. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) indicated that UPA interacted with the four CDs, which was also verified by molecular docking. Compared with the crystalline and amorphous UPA, the solubility, dissolution, and stability of the drug in the four amorphous UPA systems were significantly improved, so they were considered potentially advantageous solid forms. Our research shows that CDs can be used as new effective excipients in amorphous systems for active pharmaceutical ingredients (API).

Probing into the amorphous mixtures of ulipristal acetate and cyclodextrins.     

Clinical study on acupuncture treatment of COVID-19: A protocol for a systematic review and meta-analysis

Background:COVID-19 is an acute respiratory infectious disease, which makes people difficult to breathe; in addition, it is often accompanied by headache, olfaction, and taste disorders of the neurological manifestations. Acupuncture has been proved to have a therapeutic effect on various neurologic manifestations. This study is designed to evaluate the effectiveness and safety of acupuncture for the neurologic manifestations in COVID-19.Methods:Randomized controlled trials from December 2019 to July 2021 will be included without restrictions on language or publication date. PubMed, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Databases (CBM), China National Knowledge Infrastructure (CNKI), Wanfang database, and VIP database will be searched. Two researchers will independently select studies, extract data, and evaluate study quality. Cochrane risk of bias tool for randomized trials will be used to assess the risk of bias of included studies. Statistical analyses will be performed using the Review Manager V.5.3 and stata 14.0.Ethics and dissemination:This study will not involve personal information. Ethical approval will not be required. We will publish the results in a peer-reviewed journal.PROSPERO Trial registration number:CRD42021265699     

锁定接骨板治疗肱骨近端骨折

目的探讨肱骨近端锁定接骨板治疗肱骨近端骨折的临床疗效。方法59例肱骨近端骨折,其中男32例,女27例患者平均年龄50.5岁(22～82岁)。按Neer分类法,二部分骨折23例;三部分骨折24例;四部分骨折12例。结果X线片观察骨折愈合时间7.4周(6～12周)。按照Constant评分标准,功能优34例,良19例,中6例,优良率为89.8%。结论肱骨近端锁定接骨板治疗肱骨近端骨折手术简单、微创、固定可靠、并发症少、骨折愈合率高,别是老年骨质疏松患者首选治疗方法。