Ret Signaling Is Required for Tooth Pulp Innervation during Organogenesis.

During organogenesis, the timing and patterning of dental pulp innervation require both chemoattractive and chemorepellent cues for precise spatiotemporal regulation. Our understanding of the signaling mechanisms that regulate tooth innervation during development, as well as the basic biology of these sensory neurons, remains rudimentary. In this study, we analyzed the expression and function of glial cell line-derived neurotrophic factor (GDNF) and its receptor tyrosine kinase, Ret, in the regulation of innervation of the mouse tooth pulp by dental pulpal afferent (DPA) neurons of the trigeminal ganglion (TG). Using reporter mouse models, we demonstrate that Ret is highly expressed by a subpopulation of DPA neurons projecting to the tooth pulp at both postnatal day 7 (P7) and in the adult. In the adult tooth, GDNF is highly expressed by many cell types throughout the dental pulp. Using a ubiquitous tamoxifen (TMX)-inducible Cre ( UBC-Cre/ERT2) line crossed to Ret conditional knockout mice ( Retfx/fx), Ret was deleted immediately prior to tooth innervation, and the neural projections into P7 molars were analyzed. TMX treatment was efficient in ablating >95% of Ret protein. We observed that UBC-Cre/ERT2; Retfx/fx mice had a significant reduction in the total number of neurites present within the pulp at P7, with a significant accumulation of aberrant fibers in the dental follicle and periodontium. In agreement with these findings, inhibition of Ret signaling through in vivo administration of a highly specific pharmacologic inhibitor (1NM-PP1) of Ret also caused a substantial reduction in pulpal innervation. Taken together, these findings indicate that Ret signaling regulates the timing and patterning of tooth innervation by dental primary afferent neurons of the TG during organogenesis and provide a rationale to explore whether alterations in the GDNF-Ret pathway contribute to pathophysiological conditions in the adult dentition.

Progression of alpha-synuclein pathology in multiple system atrophy of the cerebellar type.

AIMS: The aim of this study was to identify early foci of α-synuclein (α-syn pathology) accumulation, subsequent progression and neurodegeneration in multiple system atrophy of the cerebellar type (MSA-C). METHODS: We analysed 70-µm-thick sections of 10 cases with MSA-C and 24 normal controls. RESULTS: MSA-C cases with the lowest burden of pathology showed α-syn glial cytoplasmic inclusions (GCIs) in the cerebellum as well as in medullary and pontine cerebellar projections. Cerebellar pathology was highly selective and severely involved subcortical white matter, whereas deep white matter and granular layer were only mildly affected and the molecular layer was spared. Loss of Purkinje cells increased with disease duration and was associated with neuronal and axonal abnormalities. Neocortex, basal ganglia and spinal cord became consecutively involved with the increasing burden of α-syn pathology, followed by hippocampus, amygdala, and, finally, the visual cortex. GCIs were associated with myelinated axons, and the severity of GCIs correlated with demyelination. CONCLUSIONS: Our findings indicate that cerebellar subcortical white matter and cerebellar brainstem projections are likely the earliest foci of α-syn pathology in MSA-C, followed by involvement of more widespread regions of the central nervous system and neurodegeneration with disease progression.

Comparative study of linear and curvilinear ultrasound probes to assess quadriceps rectus femoris muscle mass in healthy subjects and in patients with chronic respiratory disease.

INTRODUCTION: Ultrasound measurements of rectus femoris cross-sectional area (RFCSA) are clinically useful measurements in chronic obstructive pulmonary disease (COPD) and critically ill patients. Technical considerations as to the type of probe used, which affects image resolution, have limited widespread clinical application. We hypothesised that measurement of RFCSA would be similar with linear and curvilinear probes. METHODS: Four studies were performed to compare the use of the curvilinear probe in measuring RFCSA. Study 1 investigated agreement of RFCSA measurements using linear and curvilinear probes in healthy subjects, and in patients with chronic respiratory disease. Study 2 investigated the intra-rater and inter-rater agreement using the curvilinear probe. Study 3 investigated the agreement of RFCSA measured from whole and spliced images using the linear probe. Study 4 investigated the applicability of ultrasound in measuring RFCSA during the acute and recovery phases of an exacerbation of COPD. RESULTS: Study 1 showed demonstrated no difference in the measurement of RFCSA using the curvilinear and linear probes (308±104 mm(2) vs 320±117 mm(2), p=0.80; intraclass correlation coefficient (ICC)>0.97). Study 2 demonstrated high intra-rater and inter-rater reliability of RFCSA measurement with ICC>0.95 for both. Study 3 showed that the spliced image from the linear probe was similar to the whole image RFCSA (308±103.5 vs 263±147 mm(2), p=0.34; ICC>0.98). Study 4 confirmed the clinical acceptability of using the curvilinear probe during an exacerbation of COPD. There were relationships observed between admission RFCSA and body mass index (r=+0.65, p=0.018), and between RFCSA at admission and physical activity levels at 4 weeks post-hospital discharge (r=+0.75, p=0.006). CONCLUSIONS: These studies have demonstrated that clinicians can employ whole and spliced images from the linear probe or use images from the curvilinear probe, to measure RFCSA. This will extend the clinical applicability of ultrasound in the measurement of muscle mass in all patient groups.

A cohort study to identify simple clinical tests for chronic respiratory failure in obese patients with sleep-disordered breathing.

BACKGROUND: Chronic respiratory failure complicating sleep-disordered breathing in obese patients has important adverse clinical implications in terms of morbidity, mortality and healthcare utilisation. Screening strategies are essential to identify obese patients with chronic respiratory failure. METHOD: Prospective data were collected from patients with obesity-related sleep-disordered breathing admitted for respiratory assessment at a UK national sleep and ventilation centre. Hypercapnia was defined as an arterial partial pressure of carbon dioxide of >6kPa. RESULTS: 245 obese patients (56±13 years) with a body mass index of 48±12 kg/m(2), forced vital capacity (FVC) of 2.1±1.1 L, daytime oximetry (SpO2) of 91±6% and abnormal overnight oximetry were included in the analysis. Receiver operator curve analysis for the whole group showed that an FVC ≤3 L had a sensitivity of 90% and a specificity of 41% in predicting hypercapnia, and an SpO2 ≤95% had a sensitivity of 83% and a specificity of 63% in predicting hypercapnia. Gender differences were observed and receiver operator curve analysis demonstrated 'cut-offs' for (1) SpO2 of ≤95% for men and ≤93% for women and (2) FVC of ≤3.5 L for men and ≤2.3 L for women, in predicting hypercapnia. CONCLUSIONS: The measurement of FVC and clinic SpO2 in obese patients with abnormal overnight limited respiratory studies predicted hypercapnia. This may have clinical utility in stratifying patients attending sleep clinics.

Provision of home mechanical ventilation and sleep services for England survey.

The Department of Health is promoting the generation of specialist networks to manage long term ventilatory weaning and domiciliary non-invasive ventilation patients. Currently the availability of these services in England is not known. We performed a short survey to establish the prevalence of sleep and ventilation diagnostic and treatment services. The survey focussed on diagnostic services and Home Mechanical Ventilation (HMV) provision, and was divided into (a) availability of diagnostics, (b) funding, and (c) patient groups. This survey has confirmed that the majority of Home Mechanical Ventilation set-ups are currently for Obesity Related Respiratory Failure and Chronic Obstructive Pulmonary Disease. We have found that there is variable provision of diagnostic services, with the majority of units offering overnight oximetry (95%) but only 55% of responders providing a home mechanical ventilation service. Even more interestingly, less than two thirds of units charged their primary care trust for this service. These data may assist in the development of regional networks and specialist home mechanical ventilation centres.

Physical inactivity and risk of hospitalisation for chronic obstructive pulmonary disease.

The association between physical activity and risk of hospitalisation for chronic obstructive pulmonary disease (COPD) is not yet clear. We conducted a systematic review of the literature to fill this gap in knowledge. Eight electronic databases were searched using a selection of controlled vocabulary and keywords. The search resulted in more than 1000 initial hits, of which four met the inclusion criteria. For each identified study, relevant data were extracted and appraised. The results indicate that less physically active patients with COPD were more likely to be admitted to hospital. Consistent with a lower level of physical activity, the patients tended to have shorter walking times as well as spend fewer hours outdoors. In multivariate regression analysis, self-reported physical activity predicted hospitalisation in patients from the general population and re-hospitalisation in patients admitted for an acute exacerbation. The evidence for an association between physical activity and risk of hospitalisation for COPD is limited to a few prospective cohort studies. More research is needed to quantify the degree of physical activity associated with reduced risk of hospitalisation.

Spread of cochlear excitation during stimulation with pulsed infrared radiation: inferior colliculus measurements.

Infrared neural stimulation (INS) has received considerable attention over the last few years. It provides an alternative method to artificially stimulate neurons without electrical current or the introduction of exogenous chromophores. One of the primary benefits of INS could be the improved spatial selectivity when compared with electrical stimulation. In the present study, we have evaluated the spatial selectivity of INS in the acutely damaged cochlea of guinea pigs and compared it to stimulation with acoustic tone pips in normal-hearing animals. The radiation was delivered via a 200 µm diameter optical fiber, which was inserted through a cochleostomy into the scala tympani of the basal cochlear turn. The stimulated section along the cochlear spiral ganglion was estimated from the neural responses recorded from the central nucleus of the inferior colliculus (ICC). ICC responses were recorded in response to cochlear INS using a multichannel penetrating electrode array. Spatial tuning curves (STCs) were constructed from the responses. For INS, approximately 55% of the activation profiles showed a single maximum, ∼22% had two maxima and ∼13% had multiple maxima. The remaining 10% of the profiles occurred at the limits of the electrode array and could not be classified. The majority of ICC STCs indicated that the spread of activation evoked by optical stimuli is comparable to that produced by acoustic tone pips.

Growth mechanism and optical properties of aligned hexagonal ZnO nanoprisms synthesized by noncatalytic thermal evaporation.

Vertically aligned perfectly hexagonal-shaped ZnO nanoprisms have been grown on a Si(100) substrate via a noncatalytic thermal evaporation process by using metallic zinc powder in the presence of oxygen gas. The as-grown nanoprisms consist of ultra smooth Zn-terminated (0001) facets bounded with the {0110} surfaces. The as-synthesized products are single-crystalline with the wurtzite hexagonal phase and grown along the [0001] direction, as confirmed from the detailed structural investigations. The presence of a sharp and strong nonpolar optical phonon high-E2 mode at 437 cm(-1) in the Raman scattering spectrum further confirms good crystallinity and wurtzite hexagonal phase for the as-grown products. The as-grown nanoprisms exhibit a strong near-band-edge emission with a very weak deep-level emission in the room-temperature and low-temperature photoluminescence measurements, confirming good optical properties for the deposited products. Moreover, systematic time-dependent experiments were also performed to determine the growth process of the grown vertically aligned nanoprisms.

Spectral studies of SnO2 nanofibres prepared by electrospinning method.

Tin oxide nanofibres with 100-150 nm diameter has been prepared, for the first time by calcination of poly(vinyl acetate) (PVAc)/SnO2 composite fibres prepared by electrospinning method as precursor. Scanning electron microscopic images revealed cylindrical morphology of the fibres after calcination at 600 degrees C. Both, X-ray diffraction (XRD) and Raman spectral data confirmed the presence of phase pure tetragonal rutile tin oxide after calcination process. Room temperature photoluminescence (PL) spectra of tin oxide nanofibres under excitation at 325 nm wavelength show a strong green emission at 525 nm with a band gap of 2.41 eV. FT-IR spectra confirmed the formation of pure tin oxide after calcination at 600 degrees C and complete removal of PVAc during calcination. UV-vis spectrum of the fibres showed absorption at 315 nm due to the direct electron transfer in tin oxide.

Structural and optical properties of single-crystalline ZnO nanorods grown on silicon by thermal evaporation.

The growth of perfectly hexagonal-shaped ZnO nanorods, with Zn-terminated (0001) facets bounded with [Formula: see text] surfaces, has been performed on nickel-coated Si(100) substrate via thermal evaporation using metallic zinc powder and oxygen. Detailed structural investigations confirmed that the synthesized nanorods are single crystalline with the wurtzite hexagonal phase and preferentially grow along the c-axis direction. Raman spectra of the as-grown ZnO nanorods showed an optical-phonon E(2) mode at 438 cm(-1), indicating that as-grown nanostructures are in good crystallinity with the wurtzite hexagonal phase. The ZnO nanorods were found to show strong band edge emission with very weak or no deep-level emission, as shown by photoluminescence measurements. The clear observation of free excitons at low temperatures (13-50 K) indicates that the as-grown ZnO nanorods are of high quality.

GeO2 fibers: preparation, morphology and photoluminescence property.

Nanomicron to submicron fibers of GeO(2) have been prepared using poly(vinyl acetate) and germanium dioxide sol by electrospinning followed by high temperature calcination. The morphology of the fibers have been studied by scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. X-ray diffraction indicates that the fibers are single crystal with hexagonal alpha-phase quartz-like structure. At room temperature, the fibers show photoluminescence under excitation at 325 nm. The fibers may have potential applications in one-dimensional optoelectronic nanodevices.

Phosphorylation of the serine 60 residue within the Cdx2 activation domain mediates its transactivation capacity.

BACKGROUND & AIMS: Cdx2 is critical in intestinal proliferation and differentiation. Modulation of Cdx2 function in response to cellular signaling is to be elucidated. We hypothesize that phosphorylation of the Cdx2 activation domain can modulate its function. METHODS: The Cdx2 activation domain was delineated in transient transfections using different portions of Cdx2 fused to the Gal4-DNA binding domain. In vivo phosphorylation was studied by metabolic labeling with (32)P-orthophosphate. To study a potential phosphorylation site, polyclonal antibodies were generated: CNL was raised against amino acids 54-66 of Cdx2 and P-Cdx2-S60 against the same epitope in which serine 60 was phosphorylated. RESULTS: A critical region for transactivation resides within amino acids 60-70. Substitution of serine 60 with alanine reduces incorporation of (32)P-orthophosphate substantially. S60-phosphorylation decreases Cdx2 transactivation. Phosphorylation of serine 60 can be inhibited with the mitogen-activated protein kinase inhibitors PD98059 or UO126. P-Cdx2-S60 recognizes phosphorylated serine 60 mainly in proliferative compartment of the intestinal epithelial layer. In contrast, CNL recognizes Cdx2 predominantly in the differentiated compartment. CONCLUSIONS: The Cdx2 activation domain is phosphorylated at serine 60 via the mitogen-activated protein kinase pathway. S60-phosphorylated and S60-nonphosphorylated Cdx2 have different transcriptional activity, as well as different spatial expression patterns in the intestinal epithelium.

Treatment of acute cerebral infarction with arginine esterase: a controlled study with heparin.

BACKGROUND AND PURPOSE: [corrected] There is no treatment proven to be of definitive benefit for ischemic stroke. Arginine esterase, a natural product from a snake venom, has been shown to reduce the serum fibrinogen level in human beings and may be useful in the treatment of ischemic stroke. In the present study, we compared the therapeutic effect of arginine esterase with that of heparin. SUBJECTS AND METHODS: We studied 50 consecutive patients with acute ischemic stroke who were admitted to the Asan Medical Center. We randomly administered either arginine esterase 0.005 unit/kg x 2 times/day or heparin (activated partial thromboplastin time 2-3 times of baseline value) intravenously for 7 days. Antiplatelets were administered afterwards in both groups. Blood fibrinogen, fibrinogen degradation product (FDP) and D-dimer levels were measured at 0, 6, 12, 18 h and 1, 2, 3, 7 and 30 days after the onset of stroke. NIH stroke scale was measured daily by 2 neurologists while Barthel index and Rankin scale were assessed at 7 days and 1 month after the onset of stroke by a research nurse. All these investigators were blinded to the therapeutic regimen each patient received. RESULTS: There were no significant differences in the mean age, gender proportion, stroke subtypes and baseline neurological severity between the two groups. One patient in the arginine esterase group died in an acute stage due to massive herniation and 1 in the heparin group underwent surgery for herniation. One (arginine esterase group) died of massive gastrointestinal bleeding due to previously unrecognized stomach cancer. Otherwise, no significant clinical and laboratory side effects were observed in both groups. In the arginine-esterase treated group, D-dimer and FDP levels were significantly (p < 0.05) elevated, and fibrinogen level significantly (p < 0.05) decreased at 2-7 days after the onset of stroke compared to the heparin-treated group. However, there was no significant difference in the neurological improvement reflected by NIH stroke scale, Barthel index and Rankin scale. CONCLUSION: Arginine esterase seems to be safe and has significant fibrinolytic effects when administered in the patients with acute ischemic stroke. However, in this preliminary study, it was not superior to heparin in terms of the improvement of neurological deficits. Further studies with larger doses and a larger number of subjects are required.

Clusterin gene transcription is activated by caudal-related homeobox genes in intestinal epithelium.

Caudal-related homeobox (Cdx) proteins play an important role in development and differentiation of the intestinal epithelium. Using cDNA differential display, we identified clusterin as a prominently induced gene in a Cdx2-regulated cellular model of intestinal differentiation. Transfection experiments and DNA-protein interaction assays showed that clusterin is an immediate downstream target gene for Cdx proteins. The distribution of clusterin protein in the intestine was assessed during development and in the adult epithelium using immunohistochemistry. In the adult mouse epithelium, clusterin protein was localized in both crypt and villus compartments but not in interstitial cells of the intestinal mucosa. Together, these data suggest that clusterin is a direct target gene for Cdx homeobox proteins, and the pattern of clusterin protein expression suggests that it is associated with the differentiated state in the intestinal epithelium.

Cdx1 and cdx2 expression during intestinal development.

BACKGROUND & AIMS: The intestine-specific transcription factors Cdx1 and Cdx2 are candidate genes for directing intestinal development, differentiation, and maintenance of the intestinal phenotype. This study focused on the complex patterns of expression of Cdx1 and Cdx2 during mouse gastrointestinal development. METHODS: Embryonic and postnatal mouse tissues were analyzed by immunohistochemistry to determine protein expression of Cdx1 and Cdx2 in the developing intestinal tract. RESULTS: Cdx2 protein expression was observed at 9. 5 postcoitum (pc), whereas weak expression of Cdx1 protein was first seen at 12.5 pc in the distal developing intestine (hindgut). Expression of Cdx1 increased from 13.5 to 14.5 pc during the endoderm/epithelial transition with predominately distal expression. In contrast to Cdx1, there was intense expression of Cdx2 in all but the distal portions of the developing intestine. Cdx2 expression remained low in the distal colon throughout postnatal development. A gradient of expression formed in the crypt-villus axis, with Cdx1 primarily in the crypt and Cdx2 primarily in the villus. CONCLUSIONS: Direct comparison of the patterns of Cdx1 and Cdx2 protein expression during development as performed in this study provides new insights into their potential functional roles. The relative expression of Cdx1 to Cdx2 protein may be important in the anterior to posterior patterning of the intestinal epithelium and in defining patterns of proliferation and differentiation along the crypt-villus axis.

Cross-cultural evidence for the fundamental features of extraversion.

Psychologists have not determined the defining characteristics of extraversion. In four studies, the authors tested the hypothesis that extraversion facets are linked by reward sensitivity. According to this hypothesis, only facets that reflect reward sensitivity should load on a higher order extraversion factor. This model was tested against a model in which sociability links the facets. The authors also tested the generalizability of the model in a diverse sample of participants from 39 nations, and they tested the model using widely used extraversion scales. Results of all studies indicate that only facets that reflect reward sensitivity load on a higher order extraversion factor and that this factor correlates strongly with pleasant affect. Although sociability is undoubtedly an important part of extraversion, these results suggest that extraverts' sociability may be a by-product of reward sensitivity, rather than the core feature of the trait.

Effect of Vitex rotundifolia on immediate-type allergic reaction.

We investigated the effect of aqueous extract of Vitex rotundifolia (L.) (Verbenaceae) fruits (VRFE) on the immediate-type allergic reactions in vivo and in vitro. VRFE (10(-4)-1.0 g/kg) dose-dependently inhibited systemic allergic reaction induced by compound 48/80. When VRFE was employed in a systemic allergic reaction test, the plasma histamine levels were reduced in a dose-dependent manner. VRFE (5x10(-1) and 1.0 g/kg) inhibited passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) IgE. VRFE (10(-3)-1.0 mg/ml) also dose-dependently inhibited the histamine release from the rat peritoneal mast cells (RPMC) by compound 48/80 or anti-DNP IgE. Moreover, VRFE (10(-3) mg/ml) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha production from RPMC. These results suggest that VRFE may be beneficial in the regulation of immediate-type allergic reaction.

Development and characterization of an oxygen-dependent inducible promoter system, the modified nar promoter in a mutant Escherichia coli.

A nar promoter system (a modified nar promoter in a mutant host Escherichia coli (pMW618/W3110narL(-))), which is maximally induced under microaerobic conditions, was developed and characterized through batch and fed-batch culture to see whether the modified nar promoter can be used as an oxygen-dependent inducible promoter in the absence of nitrate ion. The modified nar promoter (pMW618) derived by mutations at -10 and -35 regions of the wild-type nar promoter does not require nitrate ion for the full induction, while a mutant host E. coli, W3110narL(-), does not express nitrate-dependent regulatory protein, NARL, from the host chromosome. In this study, it was found from fed-batch culture that the specific beta-galactosidase activity expressed from the lacZ gene fused to the modified nar promoter in the absence of nitrate ion was maximal when E. coli was grown under aerobic conditions (dissolved oxygen (DO) at 80%) to absorbance at 600 nm (OD(600)) of 35, and then the modified nar promoter was induced by lowering DO to 1-2% with alternating microaerobic and aerobic conditions. The maximal specific beta-galactosidase activity became 58,000 Miller at OD(600) of 160 with an induction ratio of 20. On the basis of these results, we conclude that the modified nar promoter system (pMW618/W3110narL(-)), requiring only reduction of DO for the full induction, provides a convenient and effective high-level expression system under conditions of fed-batch culture.

The caudal-related homeodomain protein Cdx1 inhibits proliferation of intestinal epithelial cells by down-regulation of D-type cyclins.

Cdx1 is a homeodomain transcription factor that regulates intestine-specific gene expression. Experimental evidence suggests that Cdx1 may be involved in cell cycle regulation, but its role is ill defined and the mechanisms have not been explored. We used stable transfection of inducible constructs and transient expression with a replication-deficient adenovirus to induce Cdx1 expression in rat IEC6 cells, a non-transformed intestinal epithelial cell line that does not express Cdx1 protein. Expression of Cdx1 markedly reduced proliferation of IEC6 cells with accumulation of cells in the G(0)/G(1) phase of the cell cycle. Cell cycle arrest was accompanied by an increase in the hypophosphorylated forms of the retinoblastoma protein (pRb) and the pRb-related p130 protein. Protein levels of multiple cyclin-dependent kinase inhibitors were either unchanged (p16, p18, p21, p27, and p57) or were not detected (p15 and p19). Most significantly, levels of cyclins D1 and D2 were markedly diminished with Cdx1 expression, but not cyclins D3, E, or the G(1) kinases. Additionally, cyclin-dependent kinase-4 activity was decreased in association with decreased cyclin D protein. We conclude that Cdx1 regulates intestinal epithelial cell proliferation by inhibiting progression through G(0)/G(1), most likely via modulation of cyclin D1 and D2 protein levels.