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The resonance scattering spectral probe for Pb2+ was obtained using aptamer-modified AuPd Nanoalloy. In the pH 7.0 Na2HPO4–NaH2PO4 buffer solution, the aptamer interacted with AuPd nanoalloy particles to form stable aptamer-AuPd nanoalloy probe for Pb2+ that is stable in high concentration of salt. The probe combined with Pb2+ ions to form a G-quadruplex and to release AuPd nanoalloy particles that aggregate to form big particles which led the resonance scattering (RS) intensity enhancing. The reaction solution was filtered by 0.15 μm membrane to obtain the filtration containing aptamer-AuPd nanoalloy probe that has strong catalytic effect on the electrodeless nickel particle plating reaction between Ni(II) and PO 2 3− that exhibited a strong RS peak at 508 nm. The RS intensity at 508 nm decreased when the Pb2+ concentration increased. The decreased intensity (ΔI 508nm) is linear to the concentration of 0.08–42 nM Pb2+, with regress equation of $$ \Delta {I_{{5}0{\rm{8nm}}}} = {16}.{3}\,c + {1}.{5} $$ , correlation coefficient of 0.9965, and detection limit of 0.04 nM Pb2+. The RS assay was applied to the analysis of Pb2+ in wastewater, with satisfactory results.

Single-strand deoxyribonucleic acid (ssDNA) were used to modified nanogold particle to obtain a aptamer-nanogold probe (NGssDNA) for Hg(II). The probe is not aggregated in high concentration of NaCl. In the pH 7.0 Na2HPO4-NaH2PO4 buffer solution and in the presence of high concentration of NaCl, NGssDNA interact with Hg(II) to form stable double-strand T-Hg(II)-T mismatches and to release nanogold particles from the probe. The released nanogold particles aggregated to form bigger clusters which leaded the resonance scattering (RS) intensity at 540 nm enhanced linearly with the concentration of Hg2+ in the range of 0.39–1666.7 nM, with detection of 0.1 nM. This simple, rapid, and sensitive aptamer-nanogold RS assay was applied to determination of Hg2+ in wastewater, with satisfactory results.

Luminescence thermometry usually suffer from cellular complexity of the biochemical environment (such as pH and ionic strength) and thus the accuracy and reliability of the determined intracellular temperature are directly affected. Herein, a photoluminescent nanothermometer composed of polymer encapsulated quantum dots (P-QD) has been developed. And the prepared nanothermometer exhibits some advantages: such as non-sensitivity to pH and ionic strength, as well as high detection sensitivity and ultrahigh reversibility. The intracellular temperature was accurately determined under physiological conditions with different pH and ionic strength and direct measurement of thermogenesis in individual cells has been achieved.

Materials possessing high two photon absorption (TPA) are highly desirable for a range of fields, such as three-dimensional data storage, TP microscopy (TPM) and photodynamic therapy (PDT). Specifically, for TPM, high TP excitation (TPE) brightness (σ × ϕ, where σ is TPA cross-sections and ϕ is fluorescence quantum yield), excellent photostability and minimal cytotoxicity are highly desirable. However, when TPA materials are transferred to aqueous media through molecule engineering or nanoparticle formulation, they usually suffer from the severely decrease of quantum yield (QY). Here, we report a convenient and efficient method for preparing polymer-encapsulated quantum dots (P-QD). Interestingly, the QY was considerably enhanced from original 0.33 (QDs in THF) to 0.84 (P-QD in water). This dramatic enhancement in QY is mainly from the efficiently blocking nonradiative decay pathway from the surface trap states, according to the fluorescence decay lifetimes analysis. The P-QD exhibits extremely high brightness (σ × ϕ up to 6.2 × 106 GM), high photostability, excellent colloidal stability and minimal cytotoxicity. High quality cellular TP imaging with high signal-to-background ratio (> 100) and tissue imaging with a penetration depth of 2200 μm have been achieved with P-QD as probe.

Objective: To explore the clinicopathologic features of secretory carcinoma of breast (SCB). Methods: Four cases of SCB were analyzed by light microscopy, histochemistry, immunohistochemistry and electron microscopy. The clinical data were also analyzed. Special staining of periodic acid-Schiff reaction with diastase pretreatment, immunohistochemical staining of ER, PR, HER-2, p53, MIB-1, S-100, p63, CK8/18 and EMA by En Vision method were performed. Results: Solid, cribriform, tubular, or papillary architecture may be seen. Tumor forms cystic spaces filled with abundant pale pink secretory material, positive with diastase resistant periodic acid-Schiff (PAS-DR) stains. Tumor cells were small with bland nuclei and abundant pale, eosinophilic cytoplasm, rare mitotic activity and necrosis. Immunohistochemically, tumor cells were positive for CK8/18, EMA, negative for S-100, p63 and variable partially positive for p53, ER, PR, HER-2 and MIB-1. Under electron microscopy, the tumor cells possessed numerous membrane-bound secretory vacuoles in cytoplasm lined by microvilli. Con- clusion: SCB is a rare, low-malignant neoplasm. SCB have pathology, clinical picture, treatment, follow-up, immunohisto- chemical and genetic features that distinguish them from invasive ductal carcinomas of the usual type.

Background Excessive gestational weight gain (GWG) poses negative impact on mothers and their children. It is important to understand the modifiable lifestyle factors associated with excessive GWG during pregnancy to guide future public health practice. Aim To investigate the association between physical activity during pregnancy and GWG of Chinese urban pregnant women. Methods A pregnant women cohort was established between 2005 and 2007 in Changzhou, China. Physical activity levels of pregnant women were assessed using pedometer in the 2nd and 3rd trimester, respectively. According to step counts, pregnant women were categorized into 4 different physical activity groups: Sedentary, Low Active, Somewhat Active and Active. The pregnant women were followed for eligibility and data collection from the 2nd trimester to delivery. Multiple linear regression and multiple binary logistic model were applied to determine the association between physical activity and GWG. Results Physical activity levels and GWG of 862 pregnant women were assessed, among them 473 (54.9%) experienced excessive GWG. The adjusted odds ratio (OR) was 0.59 (95%CI: 0.36 ~ 0.95) for excessive GWG in the Active group during the 2nd trimester and 0.66 (95%CI: 0.43 ~ 1.00) in the Somewhat Active group during the 3rd trimester, compared with the Sedentary group respectively. In the last two trimesters, the Active group had 1.45 kg less GWG, than the Sedentary group. The ORs of excessive GWG decreased with the increased level of physical activity (P < 0.05). Conclusion This study suggests that pregnant women being physically active have less weight gain during pregnancy.