Computationally efficient vascular input function models for quantitative kinetic modelling using DCE-MRI.

A description of the vascular input function is needed to obtain tissue kinetic parameter estimates from dynamic contrast enhanced MRI (DCE-MRI) data. This paper describes a general modelling framework for defining compact functional forms to describe vascular input functions. By appropriately specifying the components of this model it is possible to generate models that are realistic, and that ensure that the tissue concentration curves can be analytically calculated.

Using fluorodeoxythymidine to monitor anti-EGFR inhibitor therapy in squamous cell carcinoma xenografts.

Background: 3'-18F-fluoro-3'-deoxy-fluorothymidine (18F-FLT), a nucleoside analog, could monitor effects of molecularly targeted therapeutics on tumor proliferation.

Methods: We tested whether (18)F-FLT positron emission tomography (PET) uptake changes are associated with antitumor effects of erlotinib in A431 xenografts or cetuximab in SCC1 xenografts.

Results: Compared with pretreatment FLT PET scans, 3 days of erlotinib in A431 reduced the standardized uptake value (SUV) by 18%, whereas placebo increased SUV by 1% (p = .

Efficient in vitro expansion of human immunodeficiency virus (HIV)-specific T-cell responses by gag mRNA-electroporated dendritic cells from treated and untreated HIV type 1-infected individuals.

Developing an immunotherapy to keep human immunodeficiency virus type 1 (HIV-1) replication suppressed while discontinuing highly active antiretroviral therapy (HAART) is an important challenge. In the present work, we evaluated in vitro whether dendritic cells (DC) electroporated with gag mRNA can induce HIV-specific responses in T cells from chronically infected subjects. Monocyte-derived DC, from therapy-naïve and HAART-treated HIV-1-seropositive subjects, that were electroporated with consensus codon-optimized HxB2 gag mRNA efficiently expanded T cells, secreting gamma interferon (IFN-gamma) and interleukin 2 (IL-2), as well as other cytokines and perforin, upon restimulation with a pool of overlapping Gag peptides.

Primary health care in the Kimberley: is the doctor shortage much bigger than we think?

Objective: This study describes the extent to which general practitioners in the Kimberley region are available for doctor-provided primary care and relates primary care availability to need and standardised population.

Design: Data collection and analysis was based on government statistics and interviews with general practitioners, local managers and regional employers and organisations.

Results: A shortfall of 20.

The N-terminal (1-44) and C-terminal (198-243) peptides of apolipoprotein A-I behave differently at the triolein/water interface.

Apolipoprotein A-I (apoA-I), the major protein of high-density lipoprotein (HDL), moves between HDL and triacylglycerol-rich lipoproteins during metabolism. We reported that apoA-I is conformationally flexible at the triolein/water (TO/W) interface, partially desorbing at low surface pressure (Pi) but totally desorbing at Pi > 19 mN/m. We now report the different behavior of the N- and C-terminal peptides of apoA-I ([1-44]apoA-I and [198-243]apoA-I) at the TO/W interface.

Metastatic malignant melanoma of the gallbladder presenting as biliary colic: a case report and review of literature.

Malignant melanoma (MM) is the most common cancer to metastasize to the gastrointestinal tract. Autopsy reports estimate that up to 15 per cent of these patients also have gallbladder metastases, and MM accounts for up to 60 per cent of metastatic lesions to the gallbladder. However, despite its prevalence, MM to the gallbladder is reported only sparingly in the literature.

Xin, an actin binding protein, is expressed within muscle satellite cells and newly regenerated skeletal muscle fibers.

Xin is a muscle-specific actin binding protein of which its role and regulation within skeletal muscle is not well understood. Here we demonstrate that Xin mRNA is robustly upregulated (>16-fold) within 12 h of skeletal muscle injury and is localized to the muscle satellite cell population. RT-PCR confirmed the expression pattern of Xin during regeneration, as well as within primary muscle myoblast cultures, but not other known stem cell populations.

Stepping forward.

I CAN REMEMBER clearly my first day in post as England's nursing officer for diversity. It was March 1, this year, and the morning was crisp and sunny. As I walked along Whitehall to the Department of Health offices at Richmond House, I couldn't help but reflect on some of the events that have occurred here, for so long the seat of political power in the UK.

Registration of dynamic contrast-enhanced MRI using a progressive principal component registration (PPCR).

Registration of dynamic contrast-enhanced magnetic resonance images (DCE-MRI) of soft tissue is difficult. Conventional registration cost functions that depend on information content are compromised by the changing intensity profile, leading to misregistration. We present a new data-driven model of uptake patterns formed from a principal components analysis (PCA) of time-series data, avoiding the need for a physiological model.

Torsades de pointes and self-terminating ventricular fibrillation in a prescription methadone user.

Methadone is known to prolong the QT interval and precipitate torsades de pointes. A 54-year-old prescription methadone user with hypokalaemia was referred to Critical Care with acute confusion and respiratory distress. Alcohol withdrawal was the presumed precipitant.

Enhancing drug development and drug monitoring: academia, industry and government chart common goals.

A workshop was hosted by the Biomedical Imaging Science Initiative of the University of Southern California in January 2007, entitled "Imaging-based Tools: Role in Drug Development and Drug Monitoring". This workshop brought together leaders from the pharmaceutical and the imaging industries, from academia and from government, who worked together to identify technical, educational, financial and procedural roadblocks that have delayed progress in the pharmacokinetic imaging field. The outcome has been a report that identifies future actions, including the formation of a Multidisciplinary Advisory Council on Noninvasive Imaging Studies.

Antiepileptic medication during pregnancy: does fetal genotype affect outcome?

Congenital abnormalities and impaired development in childhood are attributable to fetal exposure to antiepileptic drugs (AEDs). Pregnancy registries set up to obtain information about the potential risks of fetal exposure to AEDs, in particular major congenital malformations (MCMs), suggest that valproate exposure increases the frequency of congenital malformations more than other AEDs. Furthermore, follow-up studies have drawn attention to cognitive impairments in later childhood after prenatal exposure to valproate.

Point-of-care testing of capillary glucose in the exclusion and diagnosis of diabetes in remote Australia.

Objectives: To determine the utility of point-of-care (POC) capillary blood glucose measurements in the diagnosis and exclusion of diabetes in usual practice in primary health care in remote areas.

Design: Cross-sectional study comparing POC capillary glucose results with corresponding venous glucose levels measured in a reference laboratory.

Participants: 200 participants aged 16-65 years enrolled: 198 had POC capillary glucose measurements; 164 also had acceptable venous glucose laboratory results.

Bayesian estimation of pharmacokinetic parameters for DCE-MRI with a robust treatment of enhancement onset time.

When applying pharmacokinetic (PK) models to dynamic contrast enhanced MRI (DCE-MRI) data it is important to appropriately deal with the enhancement onset time, because errors in the onset time will affect the PK parameter estimates. This paper presents a Bayesian approach to the estimation of the PK parameters k(ep) and K(trans) that robustly treats the onset time. This approach involves the computation of an analytically intractable integral, so two approximate methods are developed.

Gene expression signatures in the newt irises during lens regeneration.

Lens regeneration in adult newts is possible by transdifferentiation of the pigment epithelial cells (PECs) of the dorsal iris. The same cells in the ventral iris are not capable of such a process. To understand this difference in regenerative competency, we examined gene expression of 373 genes in the intact dorsal and ventral irises as well as in irises during the process of lens regeneration.

Conformation and lipid binding of a C-terminal (198-243) peptide of human apolipoprotein A-I.

Human apolipoprotein A-I (apoA-I) is the principle apolipoprotein of high-density lipoproteins that are critically involved in reverse cholesterol transport. The intrinsically flexibility of apoA-I has hindered studies of the structural and functional details of the protein. Our strategy is to study peptide models representing different regions of apoA-I.

Selective and on-demand drenching of lambs: impact on parasite populations and performance of lambs.

Aim: To determine whether drenching regimes for lambs by which a proportion (10%) of the heaviest animals was selectively left untreated, or animals are only drenched 'on demand' when faecal nematode egg counts (FEC) exceeded a threshold level, would result in measurable increases in parasite larval challenge in the autumn and/or decreases in the performance of lambs.

Methods: A replicated study compared three drenching strategies in which mobs of lambs (n=360 in total) received either: a five-drench preventive programme, administered to all animals (Treatment 1); a five-drench preventive programme, but the 10% heaviest animals left untreated each time (Treatment 2); or drench treatments administered only when FEC exceeded 500 eggs per gram of faeces (epg) (Treatment 3). After the five-drench programme, animals in Treatments 1 and 2 were treated according to FEC as for Treatment 3.

Drenching adult ewes: implications of anthelmintic treatments pre- and post-lambing on the development of anthelmintic resistance.

Aims: To test the hypothesis that peri-parturient anthelmintic treatment of adult ewes, either pre-lambing with a controlled- release capsule (CRC) or at tail-docking with a short-acting oral formulation, would increase the rate of development of anthelmintic resistance, as compared to not drenching ewes and giving an additional drench to lambs in the autumn. Also, to evaluate the potential of routinely leaving 15% of the heaviest lambs untreated when drenching, as a means of slowing the development of anthelmintic resistance.

Methods: A replicated farmlet trial was run from 1999- 2004.

Intracranial vascular anomalies in patients with morning glory disk anomaly.

Purpose: An association between morning glory disk anomaly (MGDA) and intracranial vascular anomalies including Moyamoya disease has been recognized. We evaluated a series of patients with MGDA to ascertain the frequency of cerebrovascular anomalies.

Design: Retrospective observational case series.

Nonlinear phase correction of navigated multi-coil diffusion images.

Cardiac pulsatility causes a nonrigid motion of the brain. In multi-shot diffusion imaging this leads to spatially varying phase changes that must be corrected. A conjugate gradient based reconstruction is presented that includes phase changes measured using two-dimensional navigator echoes, coil sensitivity information, navigator-determined weightings, and data from multiple coils and averages.

Cellular electroporation induces dedifferentiation in intact newt limbs.

Newts have the remarkable ability to regenerate lost appendages including their forelimbs, hindlimbs, and tails. Following amputation of an appendage, the wound is rapidly closed by the migration of epithelial cells from the proximal epidermis. Internal cells just proximal to the amputation plane begin to dedifferentiate to form a pool of proliferating progenitor cells known as the regeneration blastema.

Effective treatment of scalp psoriasis using the excimer (308 nm) laser.

Background: Psoriasis of the scalp can be a major therapeutic challenge as response to topical medication is often inadequate. The excimer laser has potential for providing local phototherapy as its high irradiance makes treatment at this site a practical option.

Objectives: To analyze retrospectively results of treating scalp psoriasis with the excimer (308 nm) laser.

Computed tomography of pediatric stroke.

The causes of stroke in the children are varied. Magnetic resonance imaging (MRI) is generally accepted as the study of choice for definitive diagnosis of ischemic injury. However, often times MRI is not immediately available in the acute setting.