Effects of salivary pH on coating durability of two different aesthetic archwire coatings under a simulated intraoral environment.

OBJECTIVES: This study compared the effects of normal salivary pH, and acidic pH found in patients with poor oral hygiene, on the durability of aesthetic archwire coated with epoxy resin and polytetrafluoroethylene (PTFE). METHODS: The posterior parts of the archwires were sectioned into 20 mm segments (N = 102) and divided among six groups. Four groups were treated with different pH levels and two served as controls. The specimens were immersed in individual test tubes containing 10 ml of artificial saliva adjusted to a pH of 6.75 or 3.5. The tubes were sealed and stored in a 37 °C water bath for 28 days. After 28 days, the specimens were ligated to brackets embedded in an acrylic block and subjected to mechanical stress using an electronic toothbrush for 210 s. The specimens were photographed, and images were measured for coating loss using AutoCAD® software. Surface morphology was observed using a scanning electron microscope (SEM). RESULTS: Significant coating loss (p < 0.001) was found in the epoxy resin groups, regardless of pH value, but not in the PTFE groups. The acidic pH caused epoxy resin layer coating loss by twice as much as normal pH. SEM revealed existing manufacturing defects on the as-received epoxy resin coating, whereas the retrieved epoxy resin demonstrated rupture, roughness, and coating loss in multiple locations. SIGNIFICANCE: Epoxy resin coatings demonstrate poor durability in acidic environments. This condition is worsened by the existing manufacturing defects found on as-received archwires. Hence, archwires coated with epoxy resin are not recommended in patients with poor oral hygiene.

S100 Staining Adds to the Prognostic Significance of the Combination of Perineural Invasion and Lymphovascular Invasion in Colorectal Cancer.

Studies have suggested that perineural invasion (PNI) and lymphovascular invasion (LVI) serve as independent prognostic factors in colorectal cancer (CRC). Currently, little is known regarding the combination of PNI and LVI as prognostic factors, independent of stage. We hypothesized that this combination was a better prognostic marker than either PNI or LVI alone, and that S100 staining would detect PNI not seen with hematoxylin and eosin (H&E). Surgical pathology slides were retrospectively reviewed for 151 stages I to IV CRC patients who had surgery between January 1, 2008 and December 8, 2008 at 3 Hackensack Meridian Health hospitals in New Jersey. PNI and LVI were detected by H&E staining and a subset of 127 patient samples were additionally examined for PNI by S100 staining. Correlation between staining characteristics and patient outcomes was assessed using the Pearson χ tests and the Fisher exact tests. Survival was analyzed using Kaplan-Meier methods. Of the 151 cases reviewed, 30.5% were positive for PNI and 35.1% were positive for LVI by H&E. The use of S100 staining for PNI enabled its detection in 27 additional cases. Median time from patient diagnosis to death was significantly shorter for patients who were positive for both PNI and LVI (P<0.001). PNI and LVI were individual markers for poor survival in CRC patients and their combined presence had an even worse outcome. Failure to detect PNI on H&E can be overcome by S100 staining.

Tuberculosis vaccine candidates based on mycobacterial cell envelope components.

Even after decades searching for a new and more effective vaccine against tuberculosis, the scientific community is still pursuing this goal due to the complexity of its causative agent, Mycobacterium tuberculosis (Mtb). Mtb is a microorganism with a robust variety of survival mechanisms that allow it to remain in the host for years. The structure and nature of the Mtb envelope play a leading role in its resistance and survival. Mtb has a perfect machinery that allows it to modulate the immune response in its favor and to adapt to the host's environmental conditions in order to remain alive until the moment to reactivate its normal growing state. Mtb cell envelope protein, carbohydrate and lipid components have been the subject of interest for developing new vaccines because most of them are responsible for the pathogenicity and virulence of the bacteria. Many indirect evidences, mainly derived from the use of monoclonal antibodies, support the potential protective role of Mtb envelope components. Subunit and DNA vaccines, lipid extracts, liposomes and membrane vesicle formulations are some examples of technologies used, with encouraging results, to evaluate the potential of these antigens in the protective response against Mtb.

Stereospermum fimbriatum as a Potential Source of Phytochemicals: A Review of Stereospermum Genus.

Stereospermum fimbriatum is one of the medicinal plants that has been claimed to be used traditionally to treat several illnesses such as stomachache, earache, skin irritation and postpartum illness. The genus of this plant is known to possess medicinal properties in every part of the plant. Therapeutic potential of S. fimbriatum is anticipated based on numerous previous studies that documented variety of phytochemical contents and bioactivity of the genus. The most reported bioactivities of its genus are antimicrobial, antioxidant, anti-diabetic, anti-inflammatory, anti-diarrheal and analgesic activities. S. fimbriatum is a rare species that has not been discovered yet. Thus, this review aims at highlighting the potentials of S. fimbriatum by collecting available data on the bioactivities of its genus and set the directions for future research on this plant.

Three-Dimensional Optoacoustic and Laser-Induced Ultrasound Tomography System for Preclinical Research in Mice: Design and Phantom Validation.

In this work, we introduce a novel three-dimensional imaging system for in vivo high-resolution anatomical and functional whole-body visualization of small animal models developed for preclinical and other type of biomedical research. The system (LOUIS-3DM) combines a multiwavelength optoacoustic tomography (OAT) and laser-induced ultrasound tomography (LUT) to obtain coregistered maps of tissue optical absorption and speed of sound, displayed within the skin outline of the studied animal. The most promising applications of the LOUIS-3DM include 3D angiography, cancer research, and longitudinal studies of biological distributions of optoacoustic contrast agents.

Carrier-envelope phase control over pathway interference in strong-field dissociation of H2+.

The dissociation of an H2+ molecular-ion beam by linearly polarized, carrier-envelope-phase-tagged 5 fs pulses at 4×10(14) W/cm2 with a central wavelength of 730 nm was studied using a coincidence 3D momentum imaging technique. Carrier-envelope-phase-dependent asymmetries in the emission direction of H+ fragments relative to the laser polarization were observed. These asymmetries are caused by interference of odd and even photon number pathways, where net zero-photon and one-photon interference predominantly contributes at H+ + H kinetic energy releases of 0.2-0.45 eV, and net two-photon and one-photon interference contributes at 1.65-1.9 eV. These measurements of the benchmark H2+ molecule offer the distinct advantage that they can be quantitatively compared with ab initio theory to confirm our understanding of strong-field coherent control via the carrier-envelope phase.

Multiphoton above threshold effects in strong-field fragmentation.

We present a study of multiphoton dissociative ionization from molecules. By solving the time-dependent Schrödinger equation for H(2)(+) and projecting the solution onto double continuum scattering states, we observe the correlated electron-nuclear ionization dynamics in detail. We show-for the first time-how multiphoton structure prevails as long as one accounts for the energies of all the fragments. Our current work provides a new avenue to analyze strong-field fragmentation that leads to a deeper understanding of the correlated molecular dynamics.

Field-free orientation of CO molecules by femtosecond two-color laser fields.

We report the first experimental observation of nonadiabatic field-free orientation of a heteronuclear diatomic molecule (CO) induced by an intense two-color (800 and 400 nm) femtosecond laser field. We monitor orientation by measuring fragment ion angular distributions after Coulomb explosion with an 800 nm pulse. The orientation of the molecules is controlled by the relative phase of the two-color field. The results are compared to quantum mechanical rigid rotor calculations. The demonstrated method can be applied to study molecular frame dynamics under field-free conditions in conjunction with a variety of spectroscopy methods, such as high-harmonic generation, electron diffraction, and molecular frame photoelectron emission.

Suppressed dissociation of H(2)(+) vibrational states by reduced dipole coupling.

The suppression of H(2)(+) strong-field dissociation has intrigued experimentalists and theorists since the early days of laser-molecular science. We unravel a vibrational suppression effect due to weak dipole-matrix element coupling strengths of certain vibrational states, dependent on the laser frequency-a form of Cooper minima. This effect is demonstrated by our full-dimensional calculations on H(2)(+) dissociation and persists for a broad range of laser conditions including both weak and strong-field dissociation. Using a crossed-beams coincidence, three-dimensional momentum-imaging technique, the vibrational suppression effect is clearly observed for H(2)(+) and HD(+) at 790 and 395 nm, in good agreement with our theory.

Enhancing high-order above-threshold dissociation of H2+ beams with few-cycle laser pulses.

High-order (three-photon or more) above-threshold dissociation (ATD) of H(2)(+) has generally not been observed using 800 nm light. We demonstrate a strong enhancement of its probability using intense 7 fs laser pulses interacting with beams of H(2)(+), HD(+), and D(2)(+) ions. The mechanism invokes a dynamic control of the dissociation pathway. These measurements are supported by theory that additionally reveals, for the first time, an unexpectedly large contribution to ATD from highly excited electronic states.

Effects of spelling errors on the perception of writers.

The authors investigated the perceived relationship between spelling errors and cognitive abilities in a series of 3 experiments. Specifically, they examined whether college students' ratings of an author's intellectual ability, logical ability, and writing ability were affected by the presence of spelling errors. In the 1st experiment, the presence of 4 spelling errors in a short essay did not significantly affect the ratings. The spelling ability of college students, as measured by a standard oral dictation spelling test, was moderately conelated with a brief test of intelligence. In a 2nd experiment, college students rated the author of a short essay as having lower ability when there was a large number of spelling errors. The effect was more pronounced on the ratings of writing ability than it was on the ratings of logical ability or intellectual ability. This finding was replicated in a 3rd experiment, in which the essay contained misspellings actually made by writers. The results suggest that spelling errors can affect how people perceive writers, particularly when there are many spelling errors. College students appear to attribute spelling errors more to writing ability than they do to general cognitive abilities such as intelligence and logical ability.

[Uterine rupture in the third trimester after a hysteroscopic metroplasty]. / Rupture utérine au troisième trimestre aprés metroplastie hysteroscopique.

Uterine rupture during a pregnancy may occur following hysteroscopic metropasty. We report the case of a patient with a history of hysteroscopic resection complicated by of uterine rupture during pregnancy.