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Paneth cells at the bottom of small intestinal crypts secrete antimicrobial peptides, enzymes, and growth factors and contribute to pathogen clearance and maintenance of the stem cell niche. Loss of Paneth cells and their dysfunction occur commonly in various pathologies, but the mechanism underlying the control of Paneth cell function remains largely unknown. Here, we identified microRNA-195 (miR-195) as a repressor of Paneth cell development and activity by altering SOX9 translation via interaction with RNA-binding protein HuR. Tissue-specific transgenic expression of miR-195 (miR195-Tg) in the intestinal epithelium decreased the levels of mucosal SOX9 and reduced the numbers of lysozyme-positive (Paneth) cells in mice. Ectopically expressed SOX9 in the intestinal organoids derived from miR-195-Tg mice restored Paneth cell development ex vivo. miR-195 did not bind to Sox9 mRNA but it directly interacted with HuR and prevented HuR binding to Sox9 mRNA, thus inhibiting SOX9 translation. Intestinal mucosa from mice that harbored both Sox9 transgene and ablation of the HuR locus exhibited lower levels of SOX9 protein and Paneth cell numbers than those observed in miR-195-Tg mice. Inhibition of miR-195 activity by its specific antagomir improved Paneth cell function in HuR-deficient intestinal organoids. These results indicate that interaction of miR-195 with HuR regulates Paneth cell function by altering SOX9 translation in the small intestinal epithelium. NEW & NOTEWORTHY: Our results indicate that intestinal epithelial tissue-specific transgenic miR-195 expression decreases the levels of SOX9 expression, along with reduced numbers of Paneth cells. Ectopically expressed SOX9 in the intestinal organoids derived from miR-195-Tg mice restores Paneth cell development ex vivo. miR-195 inhibits SOX9 translation by preventing binding of HuR to Sox9 mRNA. These findings suggest that interaction between miR-195 and HuR controls Paneth cell function via SOX9 in the intestinal epithelium. [ABSTRACT FROM AUTHOR]

Vault RNAs (vtRNAs) are small noncoding RNAs and highly expressed in many eukaryotes. Here, we identified vtRNA2‐1 as a novel regulator of the intestinal barrier via interaction with RNA‐binding protein HuR. Intestinal mucosal tissues from patients with inflammatory bowel diseases and from mice with colitis or sepsis express increased levels of vtRNAs relative to controls. Ectopically expressed vtRNA2‐1 decreases the levels of intercellular junction (IJ) proteins claudin 1, occludin, and E‐cadherin and causes intestinal epithelial barrier dysfunction in vitro, whereas vtRNA2‐1 silencing promotes barrier function. Increased vtRNA2‐1 also decreases IJs in intestinal organoid, inhibits epithelial renewal, and causes Paneth cell defects ex vivo. Elevating the levels of tissue vtRNA2‐1 in the intestinal mucosa increases the vulnerability of the gut barrier to septic stress in mice. vtRNA2‐1 interacts with HuR and prevents HuR binding to claudin 1 and occludin mRNAs, thus decreasing their translation. These results indicate that vtRNA2‐1 impairs intestinal barrier function by repressing HuR‐facilitated translation of claudin 1 and occludin. Synopsis: Vault RNAs (vtRNAs) are small noncoding RNAs, and their levels increase in intestinal mucosa from patients with IBD. vtRNA2‐1 disrupts intestinal epithelial barrier function by decreasing intercellular junctions via interaction with HuR. vtRNA2‐1 inhibits expression of claudin 1, occludin, and E‐cadherin posttranscriptionally.vtRNA2‐1 impairs intestinal epithelial renewal and causes Paneth cell defects ex vivo.Elevating tissue vtRNA2‐1 levels increases vulnerability of gut barrier to septic stress in mice.vtRNA2‐1 interacts with HuR and prevents HuR binding to mRNAs. [ABSTRACT FROM AUTHOR]

Rhodoquinone (RQ) is a close analogue of ubiquinone (UQ) that confers diverse bacterial and eukaryotic taxa the ability to utilize fumarate as an electron acceptor in hypoxic conditions. The RquA protein, identified in a Rhodospirillum rubrum RQ-deficient mutant, has been shown to be required for RQ biosynthesis in bacteria. In this report, we demonstrate that RquA, homologous to SAM-dependent methyltransferases, is necessary and sufficient to catalyze RQ biosynthesis from UQ in vitro. Remarkably, we show that RquA uses SAM as the amino group donor in a substitution reaction that converts UQ to RQ. In contrast to known aminotransferases, RquA does not use pyridoxal 5'-phosphate (PLP) as a coenzyme, but requires the presence of Mn2+ as a cofactor. As these findings reveal, RquA provides an example of a non-canonical SAM-dependent enzyme that does not catalyze methyl transfer, instead it uses SAM in an atypical amino transfer mechanism. The RquA protein is required for rhodoquinone biosynthesis; however, its exact function is not yet known. Here, the authors demonstrate that RquA is homologous to SAM-dependent methyltransferases but functions as an aminotransferase using Mn2+ as cofactor to convert ubiquinone to rhodoquinone. [ABSTRACT FROM AUTHOR]

Intestinal Tuft cells sense luminal contents to influence the mucosal immune response against eukaryotic infection. Paneth cells secrete antimicrobial proteins as part of the mucosal protective barrier. Defects in Tuft and Paneth cells occur commonly in various gut mucosal disorders. MicroRNA-195 (miR-195) regulates the stability and translation of target mRNAs and is involved in many aspects of cell processes and pathologies. Here, we reported the posttranscriptional mechanisms by which miR-195 regulates Tuft and Paneth cell function in the small intestinal epithelium. Mucosal tissues from intestinal epithelial tissue-specific miR- 195 transgenic (miR195-Tg) mice had reduced numbers of double cortin-like kinase 1 (DCLK1)-positive (Tuft) and lysozyme-positive (Paneth) cells, compared with tissues from control mice, but there were no effects on Goblet cells and enterocytes. Intestinal organoids expressing higher miR-195 levels from miR195-Tg mice also exhibited fewer Tuft and Paneth cells. Transgenic expression of miR-195 in mice failed to alter growth of the small intestinal mucosa but increased vulnerability of the gut barrier in response to lipopolysaccharide (LPS). Studies aimed at investigating the mechanism underlying regulation of Tuft cells revealed that miR-195 directly interacted with the Dclk1 mRNA via its 30-untranslated region and inhibited DCLK1 translation. Interestingly, the RNA-binding protein HuR competed with miR-195 for binding Dclk1 mRNA and increased DCLK1 expression. These results indicate that miR-195 suppresses the function of Tuft and Paneth cells in the small intestinal epithelium and further demonstrate that increased miR-195 disrupts Tuft cell function by inhibiting DCLK1 translation via interaction with HuR. [ABSTRACT FROM AUTHOR]

Cancer-associated fibroblasts (CAFs) are the most abundant stromal cell type in the tumor microenvironment. CAFs orchestrate tumor-stromal interactions, and contribute to cancer cell growth, metastasis, extracellular matrix (ECM) remodeling, angiogenesis, immunomodulation, and chemoresistance. However, CAFs have not been successfully targeted for the treatment of cancer. The current study elucidates the significance of glypican-1 (GPC-1), a heparan sulfate proteoglycan, in regulating the activation of human bone marrow-derived stromal cells (BSCs) of fibroblast lineage (HS-5). GPC-1 inhibition changed HS-5 cellular and nuclear morphology, and increased cell migration and contractility. GPC-1 inhibition also increased pro-inflammatory signaling and CAF marker expression. GPC-1 induced an activated fibroblast phenotype when HS-5 cells were exposed to prostate cancer cell conditioned media (CCM). Further, treatment of human bone-derived prostate cancer cells (PC-3) with CCM from HS-5 cells exhibiting GPC-1 loss increased prostate cancer cell aggressiveness. Finally, GPC-1 was expressed in mouse tibia bone cells and present during bone loss induced by mouse prostate cancer cells in a murine prostate cancer bone model. These data demonstrate that GPC-1 partially regulates the intrinsic and extrinsic phenotype of human BSCs and transformation into activated fibroblasts, identify novel functions of GPC-1, and suggest that GPC-1 expression in BSCs exerts inhibitory paracrine effects on the prostate cancer cells. This supports the hypothesis that GPC-1 may be a novel pharmacological target for developing anti-CAF therapeutics to control cancer. [ABSTRACT FROM AUTHOR]

Homeostasis of the intestinal epithelium is tightly regulated by numerous extracellular and intracellular factors including vitamin D and the vitamin D receptor (VDR). VDR is highly expressed in the intestinal epithelium and is implicated in many aspects of gut mucosal pathophysiology, but the exact mechanism that controls VDR expression remains largely unknown. The RNA-binding protein human antigen R (HuR) regulates the stability and translation of target mRNAs and thus modulates various cellular processes and functions. Here we report a novel role of HuR in the posttranscriptional control of VDR expression in the intestinal epithelium. The levels of VDR in the intestinal mucosa decreased significantly in mice with ablated HuR, compared with control mice. HuR silencing in cultured intestinal epithelial cells (IECs) also reduced VDR levels, whereas HuR overexpression increased VDR abundance; neither intervention changed cellular Vdr mRNA content. Mechanistically, HuR bound to Vdr mRNA via its 3=-untranslated region (UTR) and enhanced VDR translation in IECs. Moreover, VDR silencing not only inhibited IEC migration over the wounded area in control cells but also prevented the increased migration in cells overexpressing HuR, although it did not alter IEC proliferation in vitro and growth of intestinal organoids ex vivo. The human intestinal mucosa from patients with inflammatory bowel diseases exhibited decreased levels of both HuR and VDR. These results indicate that HuR enhances VDR translation by directly interacting with its mRNA via 3=-UTR and that induced VDR by HuR is crucial for rapid intestinal epithelial restitution after wounding. [ABSTRACT FROM AUTHOR]

Based on the emerging interest in the effects of gut microbiota on cognition, this proof-of-concept study assessed how children aged 7 to 9 with low reading scores responded to the ingestion of a 3-month prebiotic supplement versus a placebo. As a secondary aim, the effects of the prebiotic on cognition, sleep, behaviour, mood, anxiety, and cortisol were assessed. In this sample, the prebiotic did not affect any of the outcome measures. [ABSTRACT FROM AUTHOR]

The aim of this cross-sectional study was to assess safe food handling practices, food safety knowledge, and adherence to implementation of Hazard Analysis and Critical Control Point among 53 food safety managers working in randomly selected food service establishments in Qatar. Face-to-face interviews with the managers at each participating food service establishment were conducted using a survey consisting of 40 questions in October–December 2015. In addition to the survey questionnaire, a checklist was used to determine the implementation of Hazard Analysis and Critical Control Point by observing actual practices applied at each food service establishment. About 66 and 68% of managers had college degree and were trained on Hazard Analysis and Critical Control Point, respectively. Results also showed that casual sit-in and fine dine-in restaurants were the only food service establishments that consistently kept records on safe food handling practices (100%), followed by fast-food food service establishments (36%). Managers' training and education level were highly correlated with the probability of their employees receiving food safety training. This first assessment on food safety knowledge and practices in Qatar demonstrated that training and education are important factors that directly impact the food safety culture in food service establishments. These findings may help government agencies establish guidelines for compulsory on-site training of food handlers for effective food safety practices in food service establishments in Qatar where the fast growing demography has led to a rapid growth in food service establishment in different cuisines leading to heterogeneity in food safety practices. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the quantification of the excimer laser-generated pressure in water in contact with a chromium or nickel surface near the liquid vaporization threshold. Background of the study; Methodology of the study; Results and discussion.

Analyzes the transient heating of thin polycrystalline silicon (polysilicon) films by argon-ion laser beams. Measurement of the static film reflectivity at elevated temperatures; Information on polysilicon; Factors that control the temperature distribution in thin films; Effect of a native oxide layer on the film optical properties.

Focuses on a study which applied a novel photothermal displacement method to probe the pulsed laser-induced feature formation of Ni-P hard disk substrates in the laser zone texturing process. Development of a laser flash photography system; Industrial applications of laser-assisted melting and surface modification processes; Results and discussion; Conclusion.

Early rapid mucosal restitution occurs as a consequence of epithelial cell migration to reseal superficial wounds, a process independent of cell proliferation. Our previous studies revealed that the canonical transient receptor potential-1 (TRPC1) functions as a store-operated Ca2+ channel (SOCs) in intestinal epithelial cells (IECs) and regulates epithelial restitution after wounding, but the exact mechanism underlying TRPC1 activation remains elusive. Caveolin-1 (Cav1) is a major component protein that is associated with caveolar lipid rafts in the plasma membrane and was recently identified as a regulator of store-operated Ca2+ entry (SOCE). Here, we showed that Cav1 plays an important role in the regulation of mucosal restitution by activating TRPC1-mediated Ca2+ signaling. Target deletion of Cav1 delayed gastric mucosal repair after exposure to hypertonic NaCl in mice, although it did not affect total levels of TRPC1 protein. In cultured IECs, Cav1 directly interacted with TRPC1 and formed Cav1/TRPC1 complex as measured by immunoprecipitation assays. Cav1 silencing in stable TRPC1-transfected cells by transfection with siCav1 reduced SOCE without effect on the level of resting [Ca2+]cyt. Inhibition of Cav1 expression by siCav1 and subsequent decrease in Ca2+ influx repressed epithelial restitution, as indicated by a decrease in cell migration over the wounded area, whereas stable ectopic overexpression of Cav1 increased Cav1/TRPC1 complex, induced SOCE, and enhanced cell migration after wounding. These results indicate that Cav1 physically interacts with and activates TRPC1, thus stimulating TRPC1-mediated Ca2+ signaling and rapid mucosal restitution after injury. [ABSTRACT FROM AUTHOR]

To determine how arterial spin labeling (ASL) measured perfusion relates to baseline metabolism, we compared resting state cerebral perfusion using pseudo-continuous ASL and cerebral glucose metabolism using 18F-FDG PET in 20 normal volunteers. Greater regional metabolism relative to perfusion was observed in the putamen, orbitofrontal and temporal lobes, whereas perfusion was relatively higher in the hippocampus and insula. In a region of interest analysis limited to gray matter, the overall mean correlation between perfusion and metabolism across voxels was r=0.43 with considerable regional variability. Cross-voxel correlations between relative perfusion and metabolism in mean ASL and PET images of all 20 subjects were the highest in the striatum (caudate: r=0.78; putamen: r=0.81), and the lowest in medial temporal structures (amygdala: r=0.087; hippocampus: r=−0.26). Correlations between mean relative perfusion and metabolism across 20 subjects were the highest in the striatum (caudate: r=0.76; putamen: r=0.58), temporal lobe (r=0.59), and frontal lobe (r=0.52), but very poor in all other structures (r<0.3), particularly in caudal structures such as the hippocampus (r=−0.0026), amygdala (r=0.18), and insula (r=0.14). Although there was good overall correlation between perfusion and glucose metabolism, regional variability should be considered when using either ASL or 18F-FDG PET as surrogate markers for neural activity. [ABSTRACT FROM AUTHOR]

Background and aims: Probe-based confocal laser endomicroscopy (pCLE; Cellvizio, Mauna Kea Technologies, Paris, France) enables in vivo histology during colonoscopy and may allow endoscopists to make real-time diagnoses. A collaboration of five experts proposed a new pCLE classification for colonic use. The aim of this study was to assess interobserver agreement and accuracy of the new pCLE classification in the colon. Patients and methods: Eligible patients were prospectively investigated by pCLE. A subset of 13 pCLE video sequences was reviewed post hoc for the establishment of a new classification, which comprised three vessel categories and seven crypt categories. All five blinded observers then scored another set of 102 video sequences, using the new classification. Histopathology was used as a reference standard. Results: The interobserver agreements on vessel and crypt architecture were 'fair' with kappa values of 0.29 and 0.27, respectively. When the classification was reduced to neoplasia vs. non-neoplasia (i.e. vessel or crypt type 3), overall agreement became 'moderate' (k=0.56). Overall sensitivity and specificity for predicting neoplasia was 66% and 83%, respectively. When all observers agreed (69% of videos), the corresponding figures became 80% and 95%. Conclusion: A new classification for pCLE in the colon had a 'moderate' interobserver agreement for differentiating neoplasia from non-neoplastic tissue in the colon. The overall accuracy (81 %) for predicting neoplasia was acceptable and became excellent (94 %) when all five observers agreed. Future research should focus on refinement and validation of the classification. [ABSTRACT FROM AUTHOR]

Workflow nets, a particular class of Petri nets, have become one of the standard ways to model and analyze workflows. Typically, they are used as an abstraction of the workflow that is used to check the so-called soundness property. This property guarantees the absence of livelocks, deadlocks, and other anomalies that can be detected without domain knowledge. Several authors have proposed alternative notions of soundness and have suggested to use more expressive languages, e.g., models with cancellations or priorities. This paper provides an overview of the different notions of soundness and investigates these in the presence of different extensions of workflow nets. We will show that the eight soundness notions described in the literature are decidable for workflow nets. However, most extensions will make all of these notions undecidable. These new results show the theoretical limits of workflow verification. Moreover, we discuss some of the analysis approaches described in the literature. [ABSTRACT FROM AUTHOR]

Synovium is the thin membranous lining of a joint. It produces synovial fluid, which lubricates and nourishes the cartilage and bone in the joint capsule. Synovial diseases in children can be classified as normal structures as potential sources of pathology (synovial folds: plicae, infrapatellar fat pad clefts), noninfectious synovial proliferation (juvenile idiopathic arthritis, hemophilic arthropathy, lipoma arborescens, synovial osteochondromatosis, pigmented villonodular synovitis, reactive synovitis), infectious synovial proliferation (pyogenic arthritis, tuberculous arthritis), deposition disease (gouty arthropathy), vascular malformation, malignancy (metastasis) and intra-/periarticular cysts and cyst-like structures. Other intra-articular neoplasms, such as intra-articular synovial sarcoma, can mimic synovial disease in children. [ABSTRACT FROM AUTHOR]

Pure akinesia with gait freezing (PAGF) has characteristic features, including freezing of gait and prominent speech disturbance without rigidity or tremor. The purpose of this study was to investigate changes in brain glucose metabolism and presynaptic dopaminergic function in PAGF. By using [(18)F] fluorodeoxyglucose (FDG) PET, 11 patients with PAGF were compared with 14 patients with probable progressive supranuclear palsy (PSP), 13 patients with Parkinson's disease (PD), and 11 normal controls. [(18)F] N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane (FP-CIT) PET was performed in 11 patients with PAGF and with 10 normal controls. The PAGF patients showed decreased glucose metabolism in the midbrain when compared with normal controls. PSP patients showed a similar topographic distribution of glucose hypometabolism with additional areas, including the frontal cortex, when compared with normal controls. The FP-CIT PET findings in patients with PAGF revealed severely decreased uptake bilaterally in the basal ganglia. These findings suggest that both PAGF and PSP may be part of the same pathophysiologic spectrum of disease. However, the reason why PAGF manifests clinically in a different manner needs to be further elucidated. [ABSTRACT FROM AUTHOR]

Pure akinesia with gait freezing (PAGF) has characteristic features, including freezing of gait and prominent speech disturbance without rigidity or tremor. The purpose of this study was to investigate changes in brain glucose metabolism and presynaptic dopaminergic function in PAGF. By using [18F] fluorodeoxyglucose (FDG) PET, 11 patients with PAGF were compared with 14 patients with probable progressive supranuclear palsy (PSP), 13 patients with Parkinson's disease (PD), and 11 normal controls. [18F] N-(3-fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) PET was performed in 11 patients with PAGF and with 10 normal controls. The PAGF patients showed decreased glucose metabolism in the midbrain when compared with normal controls. PSP patients showed a similar topographic distribution of glucose hypometabolism with additional areas, including the frontal cortex, when compared with normal controls. The FP-CIT PET findings in patients with PAGF revealed severely decreased uptake bilaterally in the basal ganglia. These findings suggest that both PAGF and PSP may be part of the same pathophysiologic spectrum of disease. However, the reason why PAGF manifests clinically in a different manner needs to be further elucidated. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver is involved in the development of nonalcoholic steatohepatitis and chronic liver injury. Impairment of hepatic transsulfuration reactions is suggested to be critically linked with alcoholic liver injury, but its role in nonalcoholic fatty liver remains unknown. We examined the early changes in sulfur-amino acid metabolism and their implication in nonalcoholic fatty liver disease (NAFLD). Male rats were provided with a standard liquid diet or a high-fat liquid diet (HFI for 3 wk. An additional group of rats received the HF diet supplemented with betaine (1%). HF diet intake elevated hepatic triglyceride and serum tumor necrosis factor-a (TNFa) concentrations. Antioxidant capacity of liver cytosol against hydroxyl and peroxyl radicals was reduced significantly. Hepatic S-adenosylmethionine (SAM) and glutathione IGSH) decreased, but hypotaurine and taurine concentrations increased. Methionine adenosyltransferase (MAT) activity, not its concentration, was depressed, whereas both activity and concentration of cysteine dioxygenase and GSH S-transferase were elevated. Betaine supplementation of the HF diet inhibited hepatic fat accumulation and serum TNFa elevation. The decrease in cytosolic antioxidant capacity was also prevented. MAT activity and its concentration were induced significantly. Hepatic SAM and GSH increased and elevation of hypotaurine and taurine was depressed. The results indicate that the metabolism of S-containing substances is significantly disturbed by the HF diet, suggesting a causal role of impairment of hepatic transsulfuration reactions in NAFLD. Betaine supplementation protects the liver from nonalcoholic steatosis and oxidative stress most probably via its effects on the transsulfuration reactions. J. Nutr. 139: 63-68, 2009. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the effectiveness of using a magnetic resonance imaging (MRI)-based method to detect rapid remodeling changes in the topology of the trabecular bone network after menopause and the protective effect of estradiol. The results obtained in evaluating the trabecular architecture and bone density of early postmenopausal women using MRI-based virtual biopsy suggest that MRI-based method is an effective tool in monitoring osteoporosis treatment.

Seed and oil contents, and fatty acid compositions of oils of 20 caneberries grown in Korea were determined. Fatty acid compositions of the oils were analyzed using GC for the extracted and methylated oils from the berry seeds. The seeds comprised 4-10% (w/w) of the wet berries and accounted for 26-62% of the dry berries. Moisture and oil contents of the berry seeds were 8-17 and 13-28% (dry basis), respectively. More than 90% of the total fatty acids in the oils from the berry seeds were unsaturated. Linoleic and linolenic acids comprised 49-70 and 13-34%, respectively, of the oils in the berry seeds. [ABSTRACT FROM AUTHOR]

Twelve zeolitic imidazolate frameworks (ZIFs; termed ZIF-1 to -12) have been synthesized as crystals by copolymerization of either Zn(II) (ZIF-1 to -4, -6 to -8, and -10 to -11) or Co(II) (ZIF-9 and -12) with imidazolate-type links. The ZIF crystal structures are based on the nets of seven distinct aluminosilicate zeolites: tetrahedral Si(Al) and the bridging O are replaced with transition metal ion and imidazolate link, respectively. In addition, one example of mixed-coordination imidazolate of Zn(II) and In(III) (ZIF-5) based on the garnet net is reported. Study of the gas adsorption and thermal and chemical stability of two prototypical members, ZIF-8 and -11, demonstrated their permanent porosity (Langmuir surface area = 1,810 m²/g), high thermal stability (up to 550°C), and remarkable chemical resistance to boiling alkaline water and organic solvents. [ABSTRACT FROM AUTHOR]