Investigation of basal cell carcinoma using dynamic focus optical coherence tomography.

Optical coherence tomography (OCT) is becoming a popular modality for skin tumor diagnosis and assessment of tumor size and margin status. We conducted a number of imaging experiments on periocular basal cell carcinoma (BCC) specimens using an OCT configuration. This configuration employs a dynamic focus (DF) procedure where the coherence gate moves synchronously with the peak of the confocal gate, which ensures better signal strength and preservation of transversal resolution from all depths.

Quantitative evaluation of scattering in optical coherence tomography skin images using the extended Huygens-Fresnel theorem.

An optical properties extraction algorithm is developed based on enhanced Huygens-Fresnel light propagation theorem, to extract the scattering coefficient of a specific region in an optical coherence tomography (OCT) image. The aim is to quantitatively analyze the OCT images. The algorithm is evaluated using a set of phantoms with different concentrations of scatterers, designed based on Mie theory.

Study of base pair mutations in proline-rich homeodomain (PRH)-DNA complexes using molecular dynamics.

Proline-rich homeodomain (PRH) is a regulatory protein controlling transcription and gene expression processes by binding to the specific sequence of DNA, especially to the sequence 5'-TAATNN-3'. The impact of base pair mutations on the binding between the PRH protein and DNA is investigated using molecular dynamics and free energy simulations to identify DNA sequences that form stable complexes with PRH. Three 20-ns molecular dynamics simulations (PRH-TAATTG, PRH-TAATTA and PRH-TAATGG complexes) in explicit solvent water were performed to investigate three complexes structurally.

Coronary and systemic arterial physiology and immunohistochemical markers related to early coronary arterial lesions in beagle dogs given the potassium channel opener, ZD6169, or the endothelin receptor antagonist, ZD1611.

We evaluated immunohistochemistry (von Willebrand Factor [vWF] or fibrinogen) and systemic and coronary arterial physiological parameters in beagle dogs to investigate early arterial lesions induced by the potassium channel opener, ZD6169, or the endothelin receptor antagonist, ZD1611. Dogs given an oral dose of ZD6169 (experiment 1) were terminated 1 day later and showed arterial and myocardial lesions. Minimal arterial lesions exhibited few condensed medial smooth muscle cells only, with others showing segmental medial necrosis occasionally with medial/adventitial acute inflammation.

Synthesis of stable isotope labelled internal standards for drug-drug interaction (DDI) studies.

The syntheses of stable isotope labelled internal standards of important CYP-isoform selective probes, like testosterone 1, diclofenac 3, midazolam 5, and dextromethorphan 7, as well as their corresponding hydroxylated metabolites 6β-hydroxytestosterone 2, 4'-hydroxydiclofenac 4, 1'-hydroxymidazolam 6 and dextrorphan 8 are reported. Microwave-enhanced H/D-exchange reactions applying either acid, base, or homogeneous and heterogeneous transition metal catalysis, or combinations thereof proved to be highly efficient for direct deuterium labelling of the above mentioned probes. Compared to conventional stepwise synthetic approaches, the combination of H/D exchange and biotransformation provides the potential for considerable time- and cost savings, in particular for the synthesis of the stable isotope labelled internal standards of 4'-hydroxydiclofenac 4 and 1'-hydroxymidazolam 6.

Simulation of tethered oligomers in nanochannels using multi-particle collision dynamics.

The effect of a high Reynold's number, pressure-driven flow of a compressible gas on the conformation of an oligomer tethered to the wall of a square channel is studied under both ideal solvent and poor solvent conditions using a hybrid multiparticle collision dynamics and molecular dynamics algorithm. Unlike previous studies, the flow field contains an elongational component in addition to a shear component as well as fluid slip near the walls and results in a Schmidt number for the polymer beads that is less than unity. In both solvent regimes the oligomer is found to extend in the direction of flow.

Free energy landscape of protein-like chains with discontinuous potentials.

In this article the configurational space of two simple protein models consisting of polymers composed of a periodic sequence of four different kinds of monomers is studied as a function of temperature. In the protein models, hydrogen bond interactions, electrostatic repulsion, and covalent bond vibrations are modeled by discontinuous step, shoulder, and square-well potentials, respectively. The protein-like chains exhibit a secondary alpha helix structure in their folded states at low temperatures, and allow a natural definition of a configuration by considering which beads are bonded.

Modeling of solvent flow effects in enzyme catalysis under physiological conditions.

A stochastic model for the dynamics of enzymatic catalysis in explicit, effective solvents under physiological conditions is presented. Analytically-computed first passage time densities of a diffusing particle in a spherical shell with absorbing boundaries are combined with densities obtained from explicit simulation to obtain the overall probability density for the total reaction cycle time of the enzymatic system. The method is used to investigate the catalytic transfer of a phosphoryl group in a phosphoglycerate kinase-ADP-bis phosphoglycerate system, one of the steps of glycolysis.

An unusual cause of limp.

Limp is a common clinical presentation in children, seen both in acute and community practice. The incidence is thought to vary between countries with suggested figures between 1.5 and 3.

Mapping quantum-classical Liouville equation: projectors and trajectories.

The evolution of a mixed quantum-classical system is expressed in the mapping formalism where discrete quantum states are mapped onto oscillator states, resulting in a phase space description of the quantum degrees of freedom. By defining projection operators onto the mapping states corresponding to the physical quantum states, it is shown that the mapping quantum-classical Liouville operator commutes with the projection operator so that the dynamics is confined to the physical space. It is also shown that a trajectory-based solution of this equation can be constructed that requires the simulation of an ensemble of entangled trajectories.

Effects of early atipamezole reversal of medetomidine-ketamine anesthesia in mice.

Rodents are often anesthetized by using ketamine and medetomidine, with reversal by atipamezole. Methods vary for times of administration of the atipamezole, and literature is lacking regarding appropriate reversal time. We investigated the recovery of mice reversed with atipamezole 10 min (early) or 40 min (late) after induction of anesthesia.

Utility of adjustable sutures in primary strabismus surgery and reoperations.

Purpose: To evaluate the success of adjustable suture (AS) and nonadjustable suture (NAS) strabismus surgery in primary procedures and reoperations.

Design: Retrospective case series.

Participants: Four hundred four patients older than 12 years who underwent strabismus surgery over a 13-year period.

Effects of exenatide in poorly controlled type 2 diabetes.

Aim: The aim of this retrospective analysis was to assess the clinical effectiveness of exenatide in patients with type 2 diabetes in routine clinical practice.

Methods: Patients with type 2 diabetes mellitus and inadequate glycemic control were commenced on exenatide in an out-patient setting. Effects on Hba1c, weight and BMI at 3- and 6-month intervals were recorded by a retrospective review of medical records.

Skin conditions are the commonest new reason people present to general practitioners in England and Wales.

Background: Knowledge of the prevalence and incidence of skin conditions is a prerequisite for designing clinical services and providing appropriate training for primary health care professionals. In the U.K.

Animal-health pharmaceuticals: research responsibilities and efforts in target animal safety and laboratory animal welfare.

As researchers in animal health, we are charged with numerous responsibilities. Among the greatest of these are ensuring the safety and effectiveness of the products we develop and the appropriate use of animals in our research efforts. The following discussion focuses primarily on the demonstration of drug safety in the species for which the product is to be licensed or registered (target animal safety) in the USA, and on our role as stewards of animal welfare in laboratory research.

Transdermal buprenorphine plus oral paracetamol vs an oral codeine-paracetamol combination for osteoarthritis of hip and/or knee: a randomised trial.

Objective: Low-dose transdermal opioids offer a new therapeutic option for osteoarthritis (OA). This study compared symptom relief obtained with buprenorphine patches plus oral paracetamol with that obtained with an oral codeine-paracetamol combination tablet (co-codamol) in older adults with OA.

Method: Two hundred and twenty people (aged ≥60 years) with OA hip and/or knee pain were randomised to treatment with 7-day buprenorphine patches plus oral paracetamol (5-25 μg/h buprenorphine patches plus 1000 mg oral paracetamol q.

Ligament reconstruction tendon interposition with mersilene augmentation.

Many surgical procedures have been described for the treatment of thumb basilar joint osteoarthritis. Augmentation of the standard ligament reconstruction tendon interposition procedure with the use of a Mersilene suture tape suspension-plasty, to recreate the stability provided by the anterior oblique ligament and increase pinch strength, will be described. Satisfaction with this procedure was evaluated through surveys completed by patients.

An improved method for specific and quantitative determination of the clopidogrel active metabolite isomers in human plasma.

Pharmacokinetic analyses of clopidogrel are hampered by the existence of multiple active metabolite isomers (H1 to H4) and their instability in blood. We sought to retest the pharmacodynamic activities of the four individual active metabolite isomers in vitro, with the ultimate aim of determining the isomers responsible for clopidogrel activity in vivo. In vitro activity was evaluated by measuring binding of [³³P]-2-methylthio-ADP on P2Y₁₂-expressing Chinese hamster ovary (CHO) cells and human platelets in platelet-rich plasma (PRP).

Tumour angiogenesis: the gap between theory and experiments.

A common experimental technique for viewing in vivo angiogenesis utilises tumours implanted into a test animal cornea. The cornea is avascular but the tumour promotes vascularisation from the limbus and the new blood vessels can be readily observed through the transparent cornea. Many of the early mathematical models for tumour angiogenesis used this scenario as their experimental template and as such assumed that there is a large gap, of the order of 2mm, between the tumour and neighbouring vasculature at the onset of angiogenesis.

Review of histopathological and molecular prognostic features in colorectal cancer.

Prediction of prognosis in colorectal cancer is vital for the choice of therapeutic options. Histopathological factors remain paramount in this respect. Factors such as tumor size, histological type and subtype, presence of signet ring morphology and the degree of differentiation as well as the presence of lymphovascular invasion and lymph node involvement are well known factors that influence outcome.

Diviner Lunar Radiometer observations of cold traps in the Moon's south polar region.

Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species.

Primary peritoneal mesothelioma: case series and literature review.

Primary peritoneal mesothelioma is a rare and aggressive tumour. We present six consecutive cases treated by our institution in the last three years. All were between 56-65 years old and only one gave a history of direct contact with asbestos.

Imaging of periocular basal cell carcinoma using en face optical coherence tomography: a pilot study.

Aim: To use en face optical coherence tomographic (OCT) imaging to identify features of tumour tissue and their correlation with histopathologic findings and to assess the effect of different wavelengths and resolutions of OCT in identifying tumour boundaries and features.

Methods: Excision specimens of consecutive biopsy-proven periocular basal cell carcinomas (BCCs) (n=8) were assessed by OCT, performing in vitro cross-section and en face scans of the tissues. Images were collected from three different machines: systems 1 and 2 had a wavelength of 1300 nm, and system 3 had a wavelength of 840 nm.