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Since the discovery of the first ferroelectric Rochelle salt, most ferroelectrics have been investigated showing thermally triggered symmetry-breaking phase transition. Although photochromism arising from geometrical isomerization has been reported earlier in 1867, such photoswitchable ferroelectric crystals have scarcely been developed to date. Herein, we report that salicylideneaniline is a photochromic ferroelectric crystal. Upon photoirradiation, the dielectric constant shows obvious switching between high and low dielectric states, and more importantly, the ferroelectric polarization demonstrates quickly and reversibly switching. This work opens the gate of developing photoswitchable ferroelectrics, which holds great potential for applications in optically controlled smart devices.

Since the discovery of TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl) in 1973, organic radical ferroics attracted widespread interest among the scientific community. However, the relatively low Curie temperature of 287 K and melting point of 311 K severely hinder its application potential. Despite extensive interest, high-temperature radical ferroics have not been found to date. Here, taking advantage of chemical design theory and supramolecular radical chemistry, we successfully designed two high-temperature organic supramolecular radical ferroics [(NH3-TEMPO)([18]crown-6)](ReO4) (1) and [(NH3-TEMPO)([18]crown-6)](ClO4) (2), which can retain the ferroelectricity up to 413 K and 450 K, respectively. To our knowledge, they are both the first supramolecular radical ferroics and unprecedented high-temperature radical ferroics, where the supramolecular component plays a vital role in the stabilization of radical and extending working temperature window. Additionally, both of them can also present the paramagnetism and non-interacting spin moments, as well as excellent piezoelectric and electrostrictive behaviors comparable to that of LiNbO3. This work provides an efficient design strategy for enriching the family of high-temperature radical ferroics, and should inspire further exploration of multi-functional organic ferroics.

Chiral perovskites have emerged as a significant class of materials showing promising optoelectronic and spintronic applications. Reports of chiral perovskite ferroelectrics, however, have been scarce. In this work, we have successfully synthesized homochiral lead-iodide perovskite ferroelectrics [(R)-N-(1-phenylethyl)ethane-1,2-diaminium]PbI4 and [(S)-N-(1-phenylethyl)ethane-1,2-diaminium]PbI4 by the chemical design of introducing a methyl group into the organic cation of the parent (N-benzylethane-1,2-diaminium)PbI4. Vibrational circular dichroism spectra identify the chiral mirroring relationship. They both undergo 222F2 type paraelectric-ferroelectric behavior at around 378 K coupled with clear ferroelastic domains "ON/OFF" switching. Besides, they exhibit an evident thermochromism with color change from orange-yellow to orange-red. To our knowledge, the discovery of integrated ferroelectricity, ferroelasticity and reversible thermochromism in chiral perovskites is unprecedented. This finding offers a resultful path to design chiral perovskite ferroelectrics and is of great inspiration to the discovery of multifunctional perovskite materials.

Aeromonas species are ubiquitous inhabitants of freshwater environments, and are responsible for fish motile aeromonad septicemia (MAS). A. hydrophila is implicated as the primary etiologic agent of MAS. Here, we analysed MAS epidemiological data for cyprinid fish in southern China, and found that A. veronii infections dominated. Consistent with this observation, A. veronii isolates were generally more virulent than A. hydrophila isolates when infecting germ-free zebrafish larvae via continuous immersion challenge. Through in vivo screening of the transposon library of the A. veronii strain Hm091, aerolysin was identified as the key virulence factor. Further results indicated that A. veronii Hm091 aerolysin disrupts the intestinal barrier of zebrafish, enabling systematic invasion by not only A. veronii Hm091 in a mono-infection, but also A. hydrophila NJ-1 in a mixed infection. Moreover, the differences in aerolysin expression and activity were the major contributor to the observed differences between the A. veronii and A. hydrophila strains regarding invasion efficacy via intestine. Together, our results provide new insights into the aetiology and pathogenesis of Aeromonas infections, and highlight the importance of A. veronii-targeted treatments in future efforts against MAS.

The gastrointestinal (GI) microbiota of vertebrates plays critical roles in nutrition, development, immunity and resistance against invasive pathogens. In the past decade, research of the GI microbiota of mammals has drastically increased our knowledge on the microbiota and their relationship with health and disease. However, our understanding of fish intestinal microbiota is limited. This review provides an overview of research on fish gut microbiota, including microbial composition, formation, factors that affect the GI microbes and characteristics of fish intestinal microbiota compared with human and mice. Further, the updated research on gnotobiotic zebrafish is elaborated and the insights gained on functions of the fish intestinal microbiota are discussed. Understanding the intestinal microbiota of fish will guide the development of probiotics, prebiotics and hopefully probiotic effectors as novel additives to improve the health of fish.

Source: doi: 10.1002/mbo3.362 This study addressed the effects of dietary Lactobacillus plantarum or/and N-acylated homoserine lactonase (AHL lactonase) on controlling Aeromonas hydrophila infection in juvenile hybrid tilapia (Oreochromis niloticus♀ × O. aureus ♂). Fish were fed Lb. plantarum subsp. plantarum strain JCM1149 (108 CFU/g feed) or/and AHL lactonase AIO6 (4 U/g) and were exposed to a chronic challenge of A. hydrophila NJ-1 (105 cells/mL) for 14 days. Intestinal (foregut) alkaline phosphatase (IAP) activities were evaluated 1 day post challenge to reflect the resistance of fish against A. hydrophila infection. Parallel groups of fish with the same dietary assignments while unchallenged were also included to investigate the effect of dietary Lb. plantarum or/and AIO6 supplementation on gut health of tilapia. The results showed that IAP activity was significantly lower in fish fed with diets supplemented with Lb. plantarum JCM1149 or the combination of Lb. plantarum JCM1149 and AIO6, indicating enhanced resistance against A. hydrophila. Light microscopy and transmission electron microscopy images of foregut revealed damage caused by A. hydrophila NJ-1, but dietary Lb. plantarumJCM1149 or/and AIO6 significantly alleviated the damages. Compared to the fish immersed in A. hydrophila NJ-1, dietary Lb. plantarum JCM1149 or AIO6 could maintain the microvilli length in the foregut of tilapia. However, among the unchallenged groups of fish, the microvilli length in the foregut of tilapia fed AIO6 (singly or combination) and the microvilli density of tilapia fed AIO6 (singly) were significantly lower than those of the control, though the microvilli density in the combination treatment was significantly improved. Additionally, the dietary Lb. plantarum JCM1149 could down-regulate the expression of stress-related gene in the gut after the acute phase. In conclusion, the dietary Lb. plantarum JCM1149 is recommended to control the A. hydrophila infection in tilapia.

Background To investigate the effects of twice daily short-message-based re-education (SMRE) before taking medicine for Helicobacter pylori (H pylori) eradication. Materials and methods Treatment-naive patients with H pylori infection were prescribed 14-day quadruple regimen consisting of lansoprazole 30 mg, colloidal bismuth pectin 200 mg, amoxicillin 1000 mg, and clarithromycin 500 mg twice daily. Patients were randomly allocated to SMRE group or control group. Patients in control group received oral and written instructions at outpatient clinic. In contrast, patients in the SMRE group received extra short messages including dosage and time of administration twice daily. Successful H pylori eradication was assessed using the 13 C-urea breath test 6 weeks after treatment. The compliance, adverse events, and patient satisfaction were also analyzed. Results A total of 310 patients were enrolled in the intention-to-treat (ITT) and 283 in the per-protocol (PP) analysis. For young patients, the eradication rates were significantly higher in SMRE group than those in control group in PP analysis (88.6% vs 71.2%, P = 0.036), while for patients of all age groups, the eradication rate improvements were not statistically significant. The eradication rates in SMRE group and control group were 74.2% and 67.7% (P = 0.211) in ITT analysis and 82.1% and 73.4% (P = 0.078) in PP analysis, respectively. The compliance in SMRE group was significantly better than that in control group (84.8% vs 72.8%, P = 0.011). Conclusions Twice daily SMRE could improve the eradication rate in young population, as well as the compliance with treatment during H pylori eradication.

In the study, we intend to design a suitable localized drug delivery system (LDDS) with chitosan and poly vinyl alcohol (PVA) for treating serve periodontitis. For that, a novel formulation based on the incorporation of chitosan-based microspheres into PVA film was prepared. As the core parts of the novel formulation, chitosan-based microspheres were prepared form chitosan and/or carboxymethyl-chitosan (CM-chitosan) by using water-in-oil emulsification method. Then basic in vitro and in vivo experiments focusing on biocompatibility and biodegradability of the two chitosan-based microspheres were carried out to evaluate the feasibility of the novel LDDS. In vitro tests, besides having no hemolysis, chitosan microsphere (Cs1-Ms), and CM-chitosan microsphere (Cs2-Ms) have adsorbed little proteins on their surfaces. Moreover, plasma proteins adsorbed on Cs2-Ms, most of which can easily desorbed, are much less than that adsorbed on Cs1-Ms. This indicates that Cs2-Ms perhaps has better biocompatibility than Cs1-Ms. In vivo tests, Cs1-Ms and Cs2-Ms were subcutaneously implanted in rat to investigate the host tissue inflammatory response. Implantations of Cs1-Ms and Cs2-Ms induced a little more severe inflammation when compared with the implantation of PVA film. However, the difference on in vivo biocompatibility between Cs1-Ms and Cs2-Ms could not be confirmed by the implantation model of our experiments. Both Cs1-Ms and Cs2-Ms had suffered bioerosion when they were subcutaneously implanted. The hard and compact matrixes of Cs1-Ms were degraded very slowly, and only some trifling degradation had been found until 4 weeks of implantation. In contrast, Cs2-Ms is soft and more hydrophilic, and can be quickly degraded in a form of diffluence by the physiological circumstance. All these results suggested that Cs2-Ms had better potentials used as core parts of the novel designed LDDS in the future developments.

Our objective was to review the clinical features and radiographic manifestations of chest wall lesions in a pediatric chest unit. Twenty-five patients (11 males and 14 females, aged 14 months to 15 years) were suspected of having a chest wall lesion on the basis of clinical examination and chest radiograph. A retrospective review of clinical characteristics and radiographic findings was performed in order to define the pathology and extent of lesions and outcomes of chest wall diseases in children. Thirty-six percent of pediatric patients studied for thoracic abnormalities had anatomical variations of the thoracic cage such as sternal titling, bifid ribs, and costal cartilage convexities. Tuberculous infections of the sternum and ribs were seen in 4 cases. Osteochondromas were seen in 4 patients, and were especially noted in patients with a history of familial exostosis. Other malignant thoracic wall tumors included in this study included chondrosarcoma (n=1), Ewing's sarcoma (n=1), and primitive neuroectodermal tumor (n=2). In conclusion, the protruding lesions arising from the chest wall demonstrate a wide range of normal, congenital variant, and pathologic lesions arising from the soft tissues and bony components. Those with life-threatening lesions (less likely located in the parasternal region) are more prone to have chest pains and dyspneic respirations; in most cases, plain chest radiographs tend to have a high rate of bony or pleural involvement as well as thoracic deformities. In an endemic area of tuberculosis, costal tuberculosis should be considered in undiagnosed bony lesions; a chest CT scan could be diagnostically useful.

OBJECTIVE: Our goal was to investigate the correlation between upper airway 3-dimensional computed tomography (3-D CT) measurements and polysomnography data of patients with sleep-disordered breathing (SDB). STUDY DESIGN AND SETTING: The 3-D CT scan measurements of the retropalatal space (RP), lateral and anteroposterior diameters of RP, retroglossal space, uvular thickness, and volume of upper airway were taken prospectively from 194 consecutive SDB patients. These were correlated with patients’ respective Respiratory Distress Index (RDI), snoring index, and lowest arterial oxygen saturation gathered from polysomnographic data. RESULTS: RP (r 0.27, P 0.0001) and lateral diameter (P 0.0073) were significantly correlated with RDI. Multivariate regression model (R 2 0.286) demonstrates RP (P 0.0036) and retroglossal space (P 0.027) to be predictive of RDI. No 3-D CT parameters correlated with snoring index and lowest arterial oxygen saturation attained statistical significant. CONCLUSION: The 3-D CT scan measurements can be valuable in evaluating upper airway patency in patients with SDB. The RP was the most relevant upper airway anatomic structure identified in these patients. SIGNIFICANCE: Modification of palatal surgery to increase the lateral dimension of the RP may be a breakthrough in increasing its success rate. (Otolaryngol Head Neck Surg 2003;129:336-42.) Sleep-disordered breathing (SDB) represents a continuum of sleep disorders that range from simple snoring to severe obstructive sleep apnea syndrome (OSAS). Recent advances in the treatment of SDB for patients with and without OSAS have created the demand for a valid tool that can be used to evaluate the upper airway patency of patients undergoing surgery. Symptoms of habitual snoring and excessive daytime sleepiness are common in the general population and have a poor predictive value in identifying patients with

Carotenoids contained in plant extracts were analyzed using liquid chromatography/positive-and negative-ion atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) with a narrow-bore C 30 reversed-phase high-performance liquid chromatographic (HPLC) column and a gradient solvent system containing methanol-methyl tert-butyl ether-ammonium acetate at a flow rate of 300 μl min -1 . In addition to mass spectrometric detection, photodiode-array UV/visible absorbance detection was used between the HPLC column and mass spectrometer for additional carotenoid characterization. Positive-ion APCI produced protonated molecules and molecular ions for both xanthophylls and, unexpectedly, hydrocarbon carotenes ; and during negative-ion APCI, M -. and [M - H] - ions were observed. In order to investigate the origin of the unexpected [M + H] + ions, positive-ion APCI of β-carotene was investigated using deuterochloroform as the only solvent. Because β-carotene formed primarily deuterated ions, [M + D] + , during APCI in deuterochloroform, the mobile phase was determined to be the source of hydrogen for protonation. The hydroxylated xanthophyll lutein fragmented during positive-ion APCI to eliminate water from the protonated molecule and form the base peak of m/z 551. Using collision-induced dissociation in the ion source, additional fragmentation pathways characteristic of tandem mass spectra of carotenoids were observed such as retro-Diels-Alder fragmentation, [M - 56] +. , for α-carotene and loss of toluene from the molecular ion, [M-92] +. for lutein, α-and β-carotene. The limits of detection for protonated molecules of α-carotene and lutein were approximately 3 and 13 pmol, respectively. In negative-ion APCI, the limits of detection were approximately 3 and 1 pmol for M -1 ions of α-carotene and lutein, respectively.

High-performance liquid chromatography (HPLC)-electrospray mass spectrometry (LC-MS) was used to analyze vitamin A-active retinoids including retinoic acid, retinol, retinal, and retinyl acetate. Unlike previous LC-MS methods such as negative ion electron capture chemical ionization, no derivatization of retinoic acid was required. HPLC separations were carried out on a C30 reversed phase column with gradient elution using mobile phases containing water, methanol, and methyl-tert-butyl ether. Ammonium acetate (5 mM) was added to the mobile phase to facilitate ion pair formation during reversed phase HPLC of retinoic acid, and acetic acid (0.5% v/v) was added to the mobile phase to enhance protonation during LC-MS analysis of nonacidic retinoids. During negative ion electrospray, retinoic acid formed abundant deprotonated molecules, [M-H]-, of m/z 299 without significant fragmentation. Although retinol, retinal, and retinyl acetate did not ionize during negative ion electrospray, the positive ion electrospray mass spectra of these retinoids showed an abundant protonated molecule of m/z 285 for retinal and base peaks of m/z 269 corresponding to elimination of water or acetic acid from the protonated molecules of retinol or retinyl acetate, respectively. No ions from retinoic acid were detected during positive ion electrospray. Limits of detection for retinoic acid, retinal, retinol, and retinyl acetate were 23 pg, 1.0 ng, 0.5 ng, and 10 ng, respectively.

The new orange phosphors Sr1-xSmxWO4 (x = 0.02—0.06) are synthesized by solid state reaction of SrCO3, WO3, and Sm2O3 (alumina crucible, 1050—1100 °C, 3 h).

A 2-year-old boy presented with chronic wheezes and was refractory to medical treatment. A high carina with bilateral bronchial stenosis was erroneously diagnosed by bronchoscopic examination. Serial direct coronal computed tomographic scans showed a displaced right upper lobe tracheal bronchus associated with tracheal stenosis below the abnormal bronchus. A direct coronal computed tomographic scan of the tracheobronchial tree is a useful imaging technique for the delineation of airway configuration when the bronchoscope fails to pass beyond a stenotic region. A coronal computed tomographic scan may make invasive tracheobronchography unnecessary.