Reconstruction of large supra-eyebrow and forehead defects using the hatchet flap principle and sparing sensory nerve branches

To reconstruct a forehead defect, a plastic surgeon must be knowledgeable about the neural, vascular, and muscular anatomy. The position of fixed structures such as eyebrows and hairline should be respected. For the past 5 years, we have used double hatchet flaps for reconstruction of relatively large supra-eyebrow and forehead defects. Because this flap does not appear to be among the techniques used by young plastic surgeons, we thought that it would be valuable to report our experience.

One-year outcomes of repeated adjunctive photodynamic therapy during periodontal maintenance: a proof-of-principle randomized-controlled clinical trial

BACKGROUND: Single photodynamic therapy (PDT) has been effective in initial periodontal therapy, but only improved bleeding on probing (BoP) in maintenance patients after a single use. Repeated PDT has not been addressed. OBJECTIVES: To study the possible added benefits of repeated adjunctive PDT to conventional treatment of residual pockets in patients enrolled in periodontal maintenance. MATERIAL AND METHODS: Ten maintenance patients with 70 residual pockets [probing pocket depth (PPD)>or=5 mm] were randomly assigned for treatment five times in 2 weeks (Days 0, 1, 2, 7, 14) with PDT (test) or non-activated laser (control) following debridement. The primary outcome variable was PPD, and the secondary variables were clinical attachment level (CAL) and BoP. These were assessed at 3, 6 and 12 months following the interventions. RESULTS: Greater PPD reductions were observed in the test (-0.67 +/- 0.34; p=0.01) compared with the control patients (-0.04 +/- 0.33; NS) after 6 months. Significant CAL gain (+0.52 +/- 0.31; p=0.01) was noted for the test, but not in the control (-0.27 +/- 0.52; NS) patients after 6 months. BoP percentages decreased significantly in test (97-64%, 67%, 77%), but not control patients after 3, 6 and 12 months. CONCLUSIONS: Repeated (five times) PDT adjunctive to debridement yielded improved clinical outcomes in residual pockets in maintenance patients. The effects were best documented after 6 months.

A stochastic principle behind polar properties of condensed molecular matter

A statistical mechanics view leads to the conclusion that polar molecules allowed to populate a degree of freedom for orientational disorder in a condensed phase thermalize into a bi-polar state featuring zero net polarity. In cases of orientational disorder polar order of condensed molecular matter can only exist in corresponding sectors of opposite average polarities. Channel type inclusion compounds, single component molecular crystals, solid solutions, optically anomalous crystals, inorganic ionic crystals, biomimetic crystals and biological tissues investigated by scanning pyroelectric and phase sensitive second harmonic generation microscopy all showed domains of opposite polarities in their final grown state. For reported polar molecular crystal structures it is assumed that kinetic hindrance along one direction of the polar axis is preventing the formation of a bi-polar state, thus allowing for a kinetically controlled mono-domain state. In this review we summarize theoretical and experimental findings leading to far reaching conclusions on the polar state of solid molecular matter. “… no stationary state … of a system has an electrical dipole moment.” P. W. Anderson, Science, 1972, 177, 393.

Computed Ultrasound Tomography in Echo Mode for Imaging Speed of Sound Using Pulse-Echo Sonography: Proof of Principle

The limitations of diagnostic echo ultrasound have motivated research into novel modalities that complement ultrasound in a multimodal device. One promising candidate is speed of sound imaging, which has been found to reveal structural changes in diseased tissue. Transmission ultrasound tomography shows speed of sound spatially resolved, but is limited to the acoustically transparent breast. We present a novel method by which speed-of-sound imaging is possible using classic pulse-echo equipment, facilitating new clinical applications and the combination with state-of-the art diagnostic ultrasound. Pulse-echo images are reconstructed while scanning the tissue under various angles using transmit beam steering. Differences in average sound speed along different transmit directions are reflected in the local echo phase, which allows a 2-D reconstruction of the sound speed. In the present proof-of-principle study, we describe a contrast resolution of 0.6% of average sound speed and a spatial resolution of 1 mm (laterally) × 3 mm (axially), suitable for diagnostic applications.

Evaluating the surveillance for swine dysentery and progressive atrophic Rhinitis in closed multiplier herds using Scenario tree modelling

Background: The Swiss pig population enjoys a favourable health situation. To further promote this, the Pig Health Service (PHS) conducts a surveillance program in affiliated herds: closed multiplier herds with the highest PHS-health and hygiene status have to be free from swine dysentery and progressive atrophic rhinitis and are clinically examined four times a year, including laboratory testing. Besides, four batches of pigs per year are fattened together with pigs from other herds and checked for typical symptoms (monitored fattening groups (MF)). While costly and laborious, little was known about the effectiveness of the surveillance to detect an infection in a herd. Therefore, the sensitivity of the surveillance for progressive atrophic rhinitis and swine dysentery at herd level was assessed using scenario tree modelling, a method well established at national level. Furthermore, its costs and the time until an infection would be detected were estimated, with the final aim of yielding suggestions how to optimize surveillance. Results: For swine dysentery, the median annual surveillance sensitivity was 96.7 %, mean time to detection 4.4 months, and total annual costs 1022.20 Euro/herd. The median component sensitivity of active sampling was between 62.5 and 77.0 %, that of a MF between 7.2 and 12.7 %. For progressive atrophic rhinitis, the median surveillance sensitivity was 99.4 %, mean time to detection 3.1 months and total annual costs 842.20 Euro. The median component sensitivity of active sampling was 81.7 %, that of a MF between 19.4 and 38.6 %. Conclusions: Results indicate that total sensitivity for both diseases is high, while time to detection could be a risk in herds with frequent pig trade. From all components, active sampling had the highest contribution to the surveillance sensitivity, whereas that of MF was very low. To increase efficiency, active sampling should be intensified (more animals sampled) and MF abandoned. This would significantly improve sensitivity and time to detection at comparable or lower costs. The method of scenario tree modelling proved useful to assess the efficiency of surveillance at herd level. Its versatility allows adjustment to all kinds of surveillance scenarios to optimize sensitivity, time to detection and/or costs.

Occurrence of Brachyspira hyodysenteriae in multiplier pig herds in Switzerland

OBJECTIVE: This research was aimed to determine the occurrence of Brachyspira (B.) hyodysenteriae in Swiss multiplier pig herds. MATERIALS AND METHODS: In a pilot study a direct real-time polymerase chain reaction (PCR) method for B. hyodysenteriae was compared to culture followed by PCR on 106 samples from three herds. Subsequently 40 multiplier herds were epidemiologically characterized and analysed for the presence of B. hyodysenteriae using direct PCR on 1412 rectal swabs. For external validation 20 swabs obtained from two positive conventional herds were analysed. RESULTS: The comparison of direct PCR with culture followed by PCR resulted in a moderate agreement (kappa index: 0.58). In the two conventional herds, 35% of the samples (7/20) tested positive. Samples from 39 multipliers tested negative. In one multiplier herd, 25% (9/36) of the samples tested PCR positive. Risk factors in the multiplier herd may have been rodents or birds, but not pig purchase. CONCLUSION AND CLINICAL RELEVANCE: B. hyodysenteriae have been detected in a Swiss multiplier herd, which underlines the threat of potential spread by replacement pigs. Consequently, a Brachyspira monitoring programme was established for Swiss multiplier herds.

An Oka principle for equivariant isomorphisms

Let G be a reductive complex Lie group acting holomorphically on normal Stein spaces X and Y, which are locally G-biholomorphic over a common categorical quotient Q. When is there a global G-biholomorphism X → Y? If the actions of G on X and Y are what we, with justification, call generic, we prove that the obstruction to solving this local-to-global problem is topological and provide sufficient conditions for it to vanish. Our main tool is the equivariant version of Grauert's Oka principle due to Heinzner and Kutzschebauch. We prove that X and Y are G-biholomorphic if X is K-contractible, where K is a maximal compact subgroup of G, or if X and Y are smooth and there is a G-diffeomorphism ψ : X → Y over Q, which is holomorphic when restricted to each fibre of the quotient map X → Q. We prove a similar theorem when ψ is only a G-homeomorphism, but with an assumption about its action on G-finite functions. When G is abelian, we obtain stronger theorems. Our results can be interpreted as instances of the Oka principle for sections of the sheaf of G-biholomorphisms from X to Y over Q. This sheaf can be badly singular, even for a low-dimensional representation of SL2(ℂ). Our work is in part motivated by the linearisation problem for actions on ℂn. It follows from one of our main results that a holomorphic G-action on ℂn, which is locally G-biholomorphic over a common quotient to a generic linear action, is linearisable.