Cyanometallic charge engineering in spin crossover metal-organic frameworks.

In this study, we successfully synthesize cationic/neutral/anionic inverse-Hofmann-type spin crossover (SCO) frameworks with 1,1,2,2-tetrakis(4-(pyridine-4-yl)phenyl)-ethene ligand by means of cyanometallic charge engineering strategy. The cationic and neutral frameworks exhibit single-step thermally induced spin transition behaviors, while the SCO capability of anionic framework can be aroused by partial desolvation. This strategy provides a new idea to construct ionic SCO frameworks and extends the toolkit for SCO materials.

Comparative observations on the squamous-columnar junction of Von Ebner's glandular duct at the bottom of vallate papillae in dogs, rats, mice and human.

BACKGROUND: This paper aims to comparatively observe similarities of squamous-columnar junction (SCJ) at the opening of Von Ebner's glandular ducts at the vallate papillae in dogs, mice, rats and humans, lay a foundation for the selection of the model in future study of the carcinogenesis in SCJ at vallate papillae. MATERIALS AND METHODS: The localization of the vallate papillae in three laboratory animals and humans was comparatively observed. The differences of SCJ at vallate papillae were comparatively observed by Alcian blue, immunohistochemistry and HE staining. RESULTS: Anatomically, the canine vallate papillae were most similar to those of humans in location, whereas mice and rats only had a single, Ω-shaped, vallate papilla lying directly anterior to the posterior border of the intermolar eminence. In histology, the SCJ of dogs lacked a transition zone similar to that of the human SCJ, and there was glandular epithelium secreting acidic mucus at the opening of the rats' Von Ebner's glandular ducts. All of this suggested that the histological structure of SCJ in rats and dogs is more distinct from that of humans, whereas the histological structure of SCJ at vallate papilla in mice was more similar. CONCLUSIONS: The structure of SCJ at vallate papilla in mice is most similar to that of humans, so we conclude that mouse is the most suitable model for studying tumorigenesis in SCJ at vallate papillae in these three common laboratory animals.

Synthesis of rare-earth metal-organic frameworks to construct high-resolution sensing array for multiplex anions detection, cell imaging and blood phosphorus monitoring.

Accurate detection and differentiation of multiple anions is still a difficult problem due to their wide variety, structural similarity, and mutual interference. Hence, four rare-earth metal-organic frameworks (RE-MOFs) including Dy-MOFs, Er-MOFs, Tb-MOFs and Y-MOFs are successfully prepared by using TCPP as the ligand and rare-earth ions as the metal center via coordination chelation. It is found that 7 anions can light up their fluorescence. Thus, a high-resolution sensing array based on RE-MOFs nanoprobes is employed to differentiate these anions from intricate analytes in real-time scenarios. The distinctive host-guest response promotes the RE-MOFs nanoprobes to selectively extract the target anions from the complex samples. By taking advantage of the cross-response between RE-MOFs nanoprobes and anions, it allows to create an array for detecting target analytes using pattern recognition. Additionally, RE-MOFs nanoprobes also facilitate the quantitative analysis of these anions (PO43-, H2PO4-, HPO42-, F-, S2-, CO32- and C2O42-). More importantly, the exceptional effectiveness of this method has been demonstrated through various successful applications, including quality monitoring of 8 toothpaste brands, intracellular phosphate imaging, and blood phosphorus detection in mice with vascular calcification. These findings provide robust evidence for the efficacy and reliability of the RE-MOFs nanoprobes array for anion recognition.

Squamous-columnar junction of Von Ebner's glands may be a significant origin of squamous cell carcinomas in the base of the tongue.

Objectives: The histological origin of base of the tongue (BOT) carcinomas is still elusive, and most studies have been focusing on the lingual tonsil. In this study, we sought to identify the existence of the squamous-columnar junction (SCJ) in the human Von Ebner's glandular duct and explored the potential of that in forming squamous cell carcinomas in BOT. Materials and methods: The specific genomes of BOT carcinoma were acquired and screened out by The Cancer Genome Atlas (TCGA) database analysis. The 4-nitroquinoline-1-oxide (4-NQO)-treated mouse model was used to explore the transformation of SCJ during cancerization. We used immunohistochemistry to confirm the characteristics of SCJ in human Von Ebner's gland, which were further compared with those in the anus and cervix. Results: The SCJ in the human Von Ebner's glandular duct was found to be similar to that of the cervix and anus. The transformation zone in the 4-NQO-treated mouse model had a multilayered epithelium structure similar to that of HPV16-transgenic mice. In human, the transformation zone of Von Ebner's gland is also similar to that of the cervix and anus. Conclusion: It is the first time that the existence of SCJ in the opening of the human Von Ebner's glandular duct was confirmed. The SCJ of Von Ebner's glands may be a significant origin of squamous cell carcinomas in BOT.

Identification of cellular microRNA miR-188-3p with broad-spectrum anti-influenza A virus activity.

BACKGROUND: Influenza A virus (IAV) continues to pose serious threats to public health. The current prophylaxis and therapeutic interventions for IAV requires frequent changes due to the continuous antigenic drift and antigenic shift of IAV. Emerging evidence indicates that the host microRNAs (miRNAs) play critical roles in intricate host-pathogen interaction networks. Cellular miRNAs may directly target virus to inhibit its infection and be developed as potential anti-virus drugs. METHODS: In this study, we established a broad-spectrum anti-IAV miRNA screening method using miRanda software. The screened miRNAs were further verified by luciferase assay, viral protein expression assay and virus replication assay. RESULTS: Five cellular miRNAs (miR-188-3p, miR-345-5p, miR-3183, miR-15-3p and miR-769-3p), targeting 99.96, 95.31, 92.9, 94.58 and 97.24% of human IAV strains recorded in NCBI, respectively, were chosen for further experimental verification. Finally, we found that miR-188-3p downregulated PB2 expression at both mRNA and protein levels by directly targeted the predicted sites on PB2 and effectively inhibited the replication of IAV (H1N1, H5N6 and H7N9) in A549 cells. CONCLUSIONS: This is the first report screening cellular miRNAs that broad-spectrum inhibiting IAV infection. These findings suggested that cellular miR-188-3p could be used for RNAi-mediated anti-IAV therapeutic strategies.

Demonstration of type-II superlattice MWIR minority carrier unipolar imager for high operation temperature application.

An InAs/GaSb type-II superlattice-based mid-wavelength infrared (MWIR) 320×256 unipolar focal plane array (FPA) using pMp architecture exhibited excellent infrared image from 81 to 150 K and ∼98% operability, which illustrated the possibility for high operation temperature application. At 150 K and -50 mV operation bias, the 27 µm pixels exhibited dark current density to be 1.2×10(-5) A/cm(2), with 50% cutoff wavelength of 4.9 µm, quantum efficiency of 67% at peak responsivity (4.6 µm), and specific detectivity of 1.2×10(12) Jones. At 90 K and below, the 27 µm pixels exhibited system limited dark current density, which is below 1×10(-9) A/cm(2), and specific detectivity of 1.5×10(14) Jones. From 81 to 100 K, the FPA showed ∼11 mK NEDT by using F/2.3 optics and a 9.69 ms integration time.

Active and passive infrared imager based on short-wave and mid-wave type-II superlattice dual-band detectors.

A versatile dual-band detector capable of active and passive use is demonstrated using short-wave (SW) and mid-wave (MW) IR type-II superlattice photodiodes. A bilayer etch-stop scheme is introduced for back-side-illuminated detectors, which enhanced the external quantum efficiency both in the SWIR and MWIR spectral regions. Temperature-dependent dark current measurements of pixel-sized 27 µm detectors found the dark current density to be ~1 × 10(-5) A/cm(2) for the ~4.2 µm cutoff MWIR channel at 140 K. This corresponded to a reasonable imager noise equivalent difference in temperature of ~49 mK using F/2.3 optics and a 10 ms integration time (t(int)), which lowered to ~13 mK at 110 K using t(int)=30 ms, illustrating the potential for high-temperature operation. The SWIR channel was found to be limited by readout noise below 150 K. Excellent imagery from the dual-band imager exemplifying pixel coincidence is shown.

[Preparation and characterization of Forms A and B of benazepril hydrochloride].

OBJECTIVE: To prepare Form A and Form B of benazepril hydrochloride and to compare the differences in spectrums, thermodynamics and crystal structure between two polymorphic forms. METHODS: Form A and Form B of benazepril hydrochloride were characterized by Fourier transform infrared spectroscopy (IR), thermal gravimetric analysis (TG), differential scanning calorimetry (DSC), powder x-ray diffraction (PXRD) and single crystal x-ray diffraction (SCXRD). RESULTS: Preparation method, crystal structure and polymorphic stability of Form A and Form B of benazepril hydrochloride were obtained. Based on the analysis of crystal structure of both polymorphs, Form A belonged to monoclone space group P2(1) with a=7.8655(4)Å, b= 11.7700(6)Å, c= 13.5560(7)Å, ß= 102.9470(10)°, V=1223.07 (11)Å(3) and Z=2, while Form B belonged to orthorhombic space group P212121, with a=7.9353(8)Å, b=11.6654(11)Å, c=26.6453(16)Å, V=2466.5(4)Å(3) and Z=4. From the DSC and XRD results, Form B of benazepril hydrochloride could be transformed into Form A after heating treatment. CONCLUSION: Form A and Form B of benazepril hydrochloride are both anhydrous and displayed different polymorphs due to different molecular configuration. Furthermore, Form A exhibits more stable than Form B at high temperatures.

Highly selective two-color mid-wave and long-wave infrared detector hybrid based on Type-II superlattices.

We report a two-color mid-wave infrared (MWIR) and long-wave infrared (LWIR) co-located detector with 3 µm active region thickness per channel that is highly selective and can perform under high operating temperatures for the MWIR band. Under back-side illumination, a temperature evolution study of the MWIR detector's electro-optical performance found the 300 K background-limit with 2π field-of-view to be achieved below operating temperatures of 160 K, at which the temperature's 50% cutoff wavelength was 5.2 µm. The measured current reached the system limit of 0.1 pA at 110 K for 30 µm pixel-sized diodes. At 77 K, where the LWIR channel operated with a 50% cutoff wavelength at 11.2 µm, an LWIR selectivity of ~17% was achieved in the MWIR wave band between 3 and 4.7 µm, making the detector highly selective.

Type-II superlattice dual-band LWIR imager with M-barrier and Fabry-Perot resonance.

We report a high performance long-wavelength IR dual-band imager based on type-II superlattices with 100% cutoff wavelengths at 9.5 µm (blue channel) and 13 µm (red channel). Test pixels reveal background-limited behavior with specific detectivities as high as ~5×10¹¹ Jones at 7.9 µm in the blue channel and ~1×10¹¹ Jones at 10.2 µm in the red channel at 77 K. These performances were attributed to low dark currents thanks to the M-barrier and Fabry-Perot enhanced quantum efficiencies despite using thin 2 µm absorbing regions. In the imager, the high signal-to-noise ratio contributed to median noise equivalent temperature differences of ~20 milli-Kelvin for both channels with integration times on the order of 0.5 ms, making it suitable for high speed applications.