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A fluorescent porous organic polymer (FPOP) with strong fluorescence and tunable emission colors, was synthesized through a simple cost-effective method via Scholl coupling reaction. Experiments proved the stability and excellent detection and adsorption ability, and microporous nature of the material. Luminescence of FPOP was quenched when addition of nitroaromatic compounds. The properties along with large-scale and low-cost preparation make these FPOP potential candidates for fluorescence detection of nitroaromatic compounds. Additionally, FPOP shows higher adsorption capacity and rate than other reported adsorbents, and has the possibility of being an effective adsorbent for industrial usage. Moreover, a fluorescent test paper was further developed and is found to be sensitive to 10 –8  M level, complete with a rapid response time and visual detection. This newly developed strategy may open up an avenue for exploring porous polymers, particularly those with a strong fluorescence, for the large-scale fabrication of FPOP for various advanced applications.

The intracellular NADPH insufficient supply is the main bottleneck to the synthesis of chiral alcohols by asymmetric reduction with whole-cell catalysis. Herein, we provide a novel strategy to strengthen intracellular NADPH supply through introducing an NADP + -dependent glyceraldehyde 3-phosphate dehydrogenase ( gap B from Bacillus subtilis 168) into the Embden-Meyerhof pathway and a NAD kinase ( yfj B from E. coli MG1655) to further enhance the NADP(H) pool. A recombinant E. coli ( E. coli BL21 (DE3)/pETDuet-1- gap B- yue D&pET28a- yfj B) was constructed to co-express gap B and yfj B with a carbonyl reductase gene yue D together. The result showed that the intracellular NADPH amount increased by 134.4% with the strategy. To the model reaction (asymmetric reduction of acetophenone to S -phenyl ethanol), the yield was 3.7-fold with this strategy compared to the control. This provides a technological route for strengthening the intracellular NADPH supply in E. coli for biocatalysis and biosynthesis. Graphic Abstract

Enantiopure alcohols have received much attention due to their widespread use as pharmaceutical intermediates. In the asymmetric biosynthesis of enantiopure alcohols, the excellent performance of carbonyl reductase makes it be the best choice as the biocatalysts. In this work, an alkali-tolerant carbonyl reductase ( Bs CR, encoded by yueD ) from Bacillus subtilis (strain 168) was obtained through gene mining, and successfully heterologously expressed in Escherichia coli with pET-32a. Bs CR showed excellent alkali resistance and even can keep more than 70% of its peak activity after incubation in Tris–HCl buffer at pH 9.0 for 40 h. The Michaelis constants and maximal velocity of the Bs CR to NADPH (A) and ethyl 4-chloroacetoacetate (B) are K m A  = 5.390 × 10 −2 mmol/L, K m B  = 1.855 mmol/L, and V max  = 147.3 μmol·min −1 ·mg −1 , respectively. Applying the E. coli BL21(DE3)/pET-32a-yueD to catalyze asymmetric reduction of ethyl 4-chloroacetoacetate and acetophenone, the yield of S -CHBE reached 89.9% and S -1-phenyl ethanol reached 66.7%, and e.e. of both products reached more than 99%. This work provides a novel CR for asymmetric reduction. Graphic Abstract A carbonyl reductase ( Bs CR) and its gene were identified through gene mining, and overexpressed in Escherichia coli BL21(DE3) for whole-cell biocatalytic asymmetric reduction

Diabetes mellitus (DM) has been regarded as an important risk factor for Alzheimer’s disease (AD), and diabetic patients and animals have shown cognitive dysfunction. More research has shown that the amyloid-β (Aβ), which is a hallmark of AD, was found deposited in the hippocampus of diabetic rats. This Aβ accumulation is regulated by the receptor for advanced glycation end products (RAGE) and low-density lipoprotein receptor-related protein (LRP-1). However, the expression of RAGE and LRP-1 in diabetic rats is not very clear. In the present study, we used streptozotocin (STZ)-induced diabetic rats to investigate whether the expression of RAGE and LRP-1 is related to Aβ 1–42 deposition at the hippocampus, prefrontal lobe, and amygdala in DM. We found that diabetic rats had longer escape latency and less frequency of entrance into the target zone than that of the control group ( P  < 0.05) in the Morris water maze (MWM) test. The Aβ 1–42 expression in the hippocampus and prefrontal lobe significantly increased in the DM group compared to the control group ( P  < 0.05). RAGE increased ( P  < 0.05), while LRP-1 decreased ( P  < 0.05) in the hippocampus tissue and prefrontal lobe tissue of DM rats. The Aβ 1–42 deposition was correlated with RAGE positively ( P  < 0.05), but with LRP-1 negatively ( P  < 0.05). Further, the expression levels of Aβ 1–42 , RAGE, and LRP-1 were not changed in the amygdala between the diabetic rats and the control group. These findings indicated that upregulating RAGE and/or downregulating LRP-1 at the hippocampus and the prefrontal lobe contributed to the Aβ 1–42 accumulation and then further promoted the cognitive impairment of diabetic rats.

The purpose of this study was to evaluate the effects of lutein, zeaxanthin and meso-zeaxanthin on macular pigment optical density (MPOD) in randomized controlled trials (RCTs) among patients with age-related macular degeneration (AMD) and healthy subjects. Medline, Embase, Web of Science and Cochrane Library databases was searched through May 2016. Meta-analysis was conducted to obtain adjusted weighted mean differences (WMD) for intervention-versus-placebo group about the change of MPOD between baseline and terminal point. Pearson correlation analysis was used to determine the relationship between the changes in MPOD and blood xanthophyll carotenoids or baseline MPOD levels. Twenty RCTs involving 938 AMD patients and 826 healthy subjects were identified. Xanthophyll carotenoids supplementation was associated with significant increase in MPOD in AMD patients (WMD, 0.07; 95% CI, 0.03 to 0.11) and healthy subjects (WMD, 0.09; 95% CI, 0.05 to 0.14). Stratified analysis showed a greater increase in MPOD among trials supplemented and combined with meso-zeaxanthin. Additionally, the changes in MPOD were related with baseline MPOD levels (rAMD = −0.43, p = 0.06; rhealthy subjects = −0.71, p < 0.001) and blood xanthophyll carotenoids concentration (rAMD = 0.40, p = 0.07; rhealthy subjects = 0.33, p = 0.05). This meta-analysis revealed that lutein, zeaxanthin and meso-zeaxanthin supplementation improved MPOD both in AMD patients and healthy subjects with a dose-response relationship.

Diabetes mellitus (DM) has been regarded as an important risk factor for Alzheimer's disease (AD), and diabetic patients and animals have shown cognitive dysfunction. More research has shown that the amyloid-[beta] (A[beta]), which is a hallmark of AD, was found deposited in the hippocampus of diabetic rats. This A[beta] accumulation is regulated by the receptor for advanced glycation end products (RAGE) and low-density lipoprotein receptor-related protein (LRP-1). However, the expression of RAGE and LRP-1 in diabetic rats is not very clear. In the present study, we used streptozotocin (STZ)-induced diabetic rats to investigate whether the expression of RAGE and LRP-1 is related to A[beta]1-42 deposition at the hippocampus, prefrontal lobe, and amygdala in DM. We found that diabetic rats had longer escape latency and less frequency of entrance into the target zone than that of the control group (P < 0.05) in the Morris water maze (MWM) test. The A[beta]1-42 expression in the hippocampus and prefrontal lobe significantly increased in the DM group compared to the control group (P < 0.05). RAGE increased (P < 0.05), while LRP-1 decreased (P < 0.05) in the hippocampus tissue and prefrontal lobe tissue of DM rats. The A[beta]1-42 deposition was correlated with RAGE positively (P < 0.05), but with LRP-1 negatively (P < 0.05). Further, the expression levels of A[beta]1-42, RAGE, and LRP-1 were not changed in the amygdala between the diabetic rats and the control group. These findings indicated that upregulating RAGE and/or downregulating LRP-1 at the hippocampus and the prefrontal lobe contributed to the A[beta]1-42 accumulation and then further promoted the cognitive impairment of diabetic rats.

X-ray detectors are broadly utilized in medical imaging and product inspection. Halide perovskites recently demonstrate excellent performance for direct X-ray detection. However, ionic migration causes large noise and baseline drift, limiting the detection and imaging performance. Here we largely eliminate the ionic migration in cesium silver bismuth bromide (Cs 2 AgBiBr 6 ) polycrystalline wafers by introducing bismuth oxybromide (BiOBr) as heteroepitaxial passivation layers. Good lattice match between BiOBr and Cs 2 AgBiBr 6 enables complete defect passivation and suppressed ionic migration. The detector hence achieves outstanding balanced performance with a signal drifting one order of magnitude lower than all previous studies, low noise (1/ f noise free), a high sensitivity of 250 µC Gy air −1 cm –2 , and a spatial resolution of 4.9 lp mm −1 . The wafer area could be easily scaled up by the isostatic-pressing method, together with the heteroepitaxial passivation, strengthens the competitiveness of Cs 2 AgBiBr 6 -based X-ray detectors as next-generation X-ray imaging flat panels. Ionic migration degrades not only the characteristics of halide perovskite solar cells, but also those of perovskite X-ray detectors. Here Yang et al. employ heteroepitaxial BiOBr to passivate Cs 2 AgBiBr 6 double perovskite, which suppresses ionic migration and obtain high performance X-ray detectors.

Lead halide perovskites have exhibited excellent performance in solar cells, LEDs and detectors. Thermal properties of perovskites, such as heat capacity and thermal conductivity, have rarely been studied and corresponding devices have barely been explored. Considering the high absorption coefficient (10 4 ~10 5  cm −1 ), low specific heat capacity (296–326 J kg −1 K −1 ) and small thermal diffusion coefficient (0.145 mm 2 s −1 ), herein we showcase the successful use of perovskite in optoacoustic transducers. The theoretically calculated phonon spectrum shows that the overlap of optical phonons and acoustic phonons leads to the up-conversion of acoustic phonons, and thus results in experimentally measured low thermal diffusion coefficient. The assembled device of PDMS/MAPbI 3 /PDMS simultaneously achieves broad bandwidths (−6 dB bandwidth: 40.8 MHz; central frequency: 29.2 MHz), and high conversion efficiency (2.97 × 10 −2 ), while all these parameters are the record values for optoacoustic transducers. We also fabricate miniatured devices by assembling perovskite film onto fibers, and clearly resolve the fine structure of fisheyes, which demonstrates the strong competitiveness of perovskite based optoacoustic transducers for ultrasound imaging. Lead halide perovskites are widely used e.g. in solar cells and LEDs, but devices based on thermal properties have received little attention. Here, the authors take advantage of the thermal properties to fabricate an optoacoustic transducer with both broad bandwidth and high conversion efficiency.

Background： Gaucher＇s disease （GD） is an autosomal recessive disorder caused by a deficiency of acid β-glucosidase （glucocerebrosidase [GBA]） that results in the accumulation of glucocerebroside within macrophages. Many mutations have been reported to be associated with this disorder. This study aimed to discover more mutations and provide data for the genetic pattern of the gene, which will help the development of quick and accurate genetic diagnostic tools for this disease. Methods： Genomic DNA was obtained from peripheral blood leukocytes of the patient and Sanger sequencing is used to sequence GBA gene. Sequence alignments of mammalian β-GBA （GCase） and three-dimensional protein structure prediction of the mutation were made. A construct of this mutant and its compound heterozygous counterpart were used to measure GCase in vitro. Results： GCase is relatively conserved at p.T219A. This novel mutation differs from its wild-type in structure. Moreover, it also causes a reduction in GCase enzyme activity. Conclusion： This novel mutation （c.655A〉G, p.T219A） is a pathogenic missense mutation, which contributes to GD.

Significance: Noninvasive in vivo fast pulsatile blood flow measurement in deep tissue is important because the blood flow waveform is correlated with physiological parameters, such as blood pressure and elasticity of blood vessels. Compromised blood flow may cause diseases, such as stroke, foot ulcer, and myocardial ischemia. There is great clinical demand for a portable and cost-effective device for noninvasive pulsatile blood flow measurement. Aim: A diffuse-optics-based method, diffuse speckle pulsatile flowmetry (DSPF), was developed for fast measurement (∼300  Hz) of deep tissue blood flow noninvasively. To validate its performance, both a phantom experiment and in vivo demonstration were conducted. Approach: Over the past two decades, single-mode fibers have been used as detection fibers in most diffuse-optics-based deep tissue blood flow measurement modalities. We used a multimode (MM) detection fiber with a core size of 200  μm for diffused speckle pattern detection. A background intensity correction algorithm was implemented for speckle contrast calculation. The MM detection fiber helped to achieve a level of deep tissue blood flow measurement similar to that of conventional modalities, such as diffuse correlation spectroscopy and diffuse speckle contrast analysis, but it increases the measurement rate of blood flow to 300 Hz. Results: The design and implementation of the DSPF system were introduced. The theory of the background intensity correction for the diffused speckle pattern detected by the MM fiber was explained. A flow phantom was built for validation of the performance of the DSPF system. An in vivo cuff-induced occlusion experiment was performed to demonstrate the capability of the proposed DSPF system. Conclusions: An MM detection fiber can help to achieve fast (∼300  Hz) pulsatile blood flow measurement in the proposed DSPF method. The cost-effective device and the fiber-based flexible probe increase the usability of the DSPF system significantly.