Ability of antibodies to two new caliciviral vaccine strains to neutralise feline calicivirus isolates from the UK

This study examined a panel of 110 UK field isolates of feline calicivirus (FCV) for susceptibility to cross-neutralisation by a panel of eight antisera raised in cats infected with FCV strains F9, 255, FCVG1 and FCV431. The pairs of antisera raised against F9 or 255, neutralised 20 and 21 per cent or 37 and 56 per cent of field strains of virus respectively. In contrast, the pairs of antisera raised against the newer vaccine strains FCVG1 or FCV431 neutralised 29 and 70 per cent or 67 and 87 per cent of field strains respectively. Antisera raised against the two newer strains, namely FCVG1 and FCV431, neutralised a greater proportion of field strains of calicivirus than antisera raised against the older FCV vaccine strains F9 and 255.

Models of tibial fracture healing in normal and Nf1-deficient mice

Delayed union and nonunion are common complications associated with tibial fractures, particularly in the distal tibia. Existing mouse tibial fracture models are typically closed and middiaphyseal, and thus poorly recapitulate the prevailing conditions following surgery on a human open distal tibial fracture. This report describes our development of two open tibial fracture models in the mouse, where the bone is broken either in the tibial midshaft (mid-diaphysis) or in the distal tibia. Fractures in the distal tibial model showed delayed repair compared to fractures in the tibial midshaft. These tibial fracture models were applied to both wild-type and Nf1-deficient (Nf1+/-) mice. Bone repair has been reported to be exceptionally problematic in human NF1 patients, and these patients can also spontaneously develop tibial nonunions (known as congenital pseudarthrosis of the tibia), which are recalcitrant to even vigorous intervention. pQCT analysis confirmed no fundamental differences in cortical or cancellous bone in Nf1-deficient mouse tibiae compared to wild-type mice. Although no difference in bone healing was seen in the tibial midshaft fracture model, the healing of distal tibial fractures was found to be impaired in Nf1+/- mice. The histological features associated with nonunited Nf1+/- fractures were variable, but included delayed cartilage removal, disproportionate fibrous invasion, insufficient new bone anabolism, and excessive catabolism. These findings imply that the pathology of tibial pseudarthrosis in human NF1 is complex and likely to be multifactorial.

Temporal patterns in the acoustic signals of beaked whales at Cross Seamount

Seamounts may influence the distribution of marine mammals through a combination of increased ocean mixing, enhanced local productivity and greater prey availability. To study the effects of seamounts on the presence and acoustic behaviour of cetaceans, we deployed a high-frequency acoustic recording package on the summit of Cross Seamount during April through October 2005. The most frequently detected cetacean vocalizations were echolocation sounds similar to those produced by ziphiid and mesoplodont beaked whales together with buzz-type signals consistent with prey-capture attempts. Beaked whale signals occurred almost entirely at night throughout the six-month deployment. Measurements of prey presence with a Simrad EK-60 fisheries acoustics echo sounder indicate that Cross Seamount may enhance local productivity in near-surface waters. Concentrations of micronekton were aggregated over the seamount in near-surface waters at night, and dense concentrations of nekton were detected across the surface of the summit. Our results suggest that seamounts may provide enhanced foraging opportunities for beaked whales during the night through a combination of increased productivity, vertical migrations by micronekton and local retention of prey. Furthermore, the summit of the seamount may act as a barrier against which whales concentrate prey.

The ECRIS charge state breeding project at TRIUMF

The performance of charge state breeding with an electron cyclotron resonance (ECR) ion source intended to increase the charge state of online produced radioactive ions at the ISAC facility at TRIUMF has been investigated. A 14 GHz PHOENIX from PANTECHNIK has been setup on a test bench. Singly charged ions have been produced with several ion sources typical for the on-line operation and were injected into the charge breeder. The main purpose of the tests has been the optimization of the efficiency for the charge breeding into the desired charge state. Maximum efficiencies reached so far with the standard one step deceleration of the ions in front of the plasma are up to about 6% for noble gas ions and about 3.5% for alkalines. As ion optics simulations show, the acceptance can be increased by a two step deceleration. In order to meet the velocity acceptance of the accelerator at different A/q values a similar two gap acceleration system for the highly charged ions has been installed to allow the source to run at different voltages. For the further beam transport to the accelerator, cross sections for charge exchange of the highly charged ions with the residual gas have been determined.

High subsoil chloride concentrations reduce soil water extraction and crop yield on Vertosols in north-eastern Australia

Salinity, sodicity, acidity, and phytotoxic levels of chloride (Cl) in subsoils are major constraints to crop production in many soils of north-eastern Australia because they reduce the ability of crop roots to extract water and nutrients from the soil. The complex interactions and correlations among soil properties result in multi-colinearity between soil properties and crop yield that makes it difficult to determine which constraint is the major limitation. We used ridge-regression analysis to overcome colinearity to evaluate the contribution of soil factors and water supply to the variation in the yields of 5 winter crops on soils with various levels and combinations of subsoil constraints in the region. Subsoil constraints measured were soil Cl, electrical conductivity of the saturation extract (ECse), and exchangeable sodium percentage (ESP). The ridge regression procedure selected several of the variables used in a descriptive model, which included in-crop rainfall, plant-available soil water at sowing in the 0.90–1.10 m soil layer, and soil Cl in the 0.90–1.10 m soil layer, and accounted for 77–85% of the variation in the grain yields of the 5 winter crops. Inclusion of ESP of the top soil (0.0–0.10 m soil layer) marginally increased the descriptive capability of the models for bread wheat, barley and durum wheat. Subsoil Cl concentration was found to be an effective substitute for subsoil water extraction. The estimates of the critical levels of subsoil Cl for a 10% reduction in the grain yield were 492 mg cl/kg for chickpea, 662 mg Cl/kg for durum wheat, 854 mg Cl/kg for bread wheat, 980 mg Cl/kg for canola, and 1012 mg Cl/kg for barley, thus suggesting that chickpea and durum wheat were more sensitive to subsoil Cl than bread wheat, barley, and canola.

Modeling bone morphogenetic protein and bisphosphonate combination therapy in wild-type and Nf1 haploinsufficient mice

Recombinant bone morphogenetic proteins (BMPs) show promise in treating the orthopedic complications associated with neurofibromatosis type 1 (NF1), such as congenital pseudarthrosis of the tibia. Minimal scientific information regarding the effects of BMP in the context of NF1 is available. As abnormalities in both bone formation and resorption have been documented in Nf1-deficient mice, we hypothesized that inadequate BMP-induced bone formation could be augmented by cotreatment with the bisphosphonate zoledronic acid (ZA). First, primary osteoblasts isolated from wild type (Nf1(+/+)) and Nf1-deficient (Nf1(+/-)) mice were cultured in the presence and absence of BMP-2. While Nf1(+/-) cells exhibited less osteogenic potential than Nf1(+/+) cells, alkaline phosphatase expression and matrix mineralization for both genotypes were enhanced by BMP-2 treatment. To model this response in vivo, 20 microg BMP-2 was implanted intramuscularly into the quadriceps of mice to induce heterotopic bone. Radiographs revealed significantly less net bone formation in Nf1(+/-) mice compared to Nf1(+/+) controls. To test the effect of an antiresorptive agent, mice were cotreated twice weekly from postoperative day 3 with 0.02 mg/kg ZA or with saline. ZA treatment led to a synergistic increase in the amount of heterotopic bone in both Nf1(+/+) and Nf1(+/-) mice compared with saline controls, as measured by DEXA and histomorphometry. Thus, the anabolic deficiency noted in Nf1(+/-) mice is amenable to stimulation by BMP-2, but mineralized tissue formation remains below that of Nf1(+/+) controls. Bisphosphonate combination therapy is superior to BMP therapy alone in terms of net bone production in vivo in both wild-type and Nf1-deficient mice.

Three successful pregnancies through dietary management of fructose-1,6-bisphosphatase deficiency

Fructose-1,6-bisphosphatase (FBPase) deficiency (OMIM 229700) has been characterized as the cause of life-threatening hypoglycaemia and lactic acidaemia following prolonged fasting. The patient, an adult African-American woman, presented during the second trimester of her first pregnancy with recurrent episodes of lactic acidaemia and hypoglycaemia. She had recently been admitted to a nearby intensive care unit after presentation with profound hypoglycaemia and lactic acidosis, and was found to be pregnant. The history was remarkable for approximately 30 hospitalizations for hypoglycaemia and acidosis. She had previously undergone liver biopsy at another centre and was diagnosed with a 'glycogen storage disease', although no enzyme testing had been done for confirmation. Based on clinical symptoms, a diagnosis of FBPase deficiency was accomplished through gene sequencing, which revealed homozygosity for a panethnic, common mutation, 960/961insG in exon 7. The availability of mutation testing facilitated the confirmation of FBPase deficiency in this patient, obviating liver biopsy for enzyme activity confirmation. The patient underwent three successful pregnancies by strict compliance with dietary management, including nocturnal uncooked cornstarch to manage hypoglycaemia. The pregnancies were complicated by mild gestational diabetes, increased cornstarch requirements, and hypoglycaemia at the time of discharge from the hospital. The three infants had normal birth weights and experienced no complications during the neonatal period. The patient subsequently developed sensorineural hearing loss and early-onset cognitive impairment, despite compliance with the monitoring and treatment of hypoglycaemia. The experience with multiple pregnancies in this FBPase-deficient patient provides insight into the management of hypoglycaemia in inherited disorders of gluconeogenesis.

Driver headway: how close is too close on a motorway?

Driver headway has recently become an important question with much attention being given to unsafe headway or 'tailgating'. This paper reviews a series of recent studies undertaken at the University of Southampton, which have sought to measure and model distance keeping, demonstrating how following distance depends on a wide range of factors, some of which are only recently being explored. These include variations in following distance for any particular driver and the relationship with time to collision, variations in following distances of drivers of differing nationalities and the ability of the driver to 'read the road ahead', which may be affected by interaction with different vehicle types. It is demonstrated that providing clear unequivocal statements regarding car following and safety levels, even after such studies, is still far from straightforward.

Optimal timing of a single dose of zoledronic acid to increase strength in rat fracture repair

We hypothesized that ZA treatment would bolster fracture repair. In a rat model for closed fracture healing, a single dose of ZA at 0, 1, or 2 wk after fracture significantly increased BMC and strength of the healed fracture. Delaying the dose (1 or 2 wk after fracture) displayed superior results compared with dosing at the time of fracture.

INTRODUCTION

Bisphosphonates are known to increase bone strength and thus the resistance to fracture by decreasing osteoclastic bone resorption. These properties may enable bisphosphonates to also increase the strength of fracture repair. Zoledronic acid (ZA) is a potent bisphosphonate with a high affinity for bone mineral, allowing bolus intravenous dosing in a range of indications. In this study, we examined the application of bolus dose ZA in endochondral fracture repair.

MATERIALS AND METHODS

Carbon-14 labeled ZA was used in a closed rat fracture model. Rats were divided into five treatment groups (n = 25 per group): saline control, local ZA (0.01 mg/kg), and three systemic bolus ZA groups (0.1 mg/kg) with different administration times: at fracture, 1 wk after fracture, and 2 wk after fracture. Rats were killed 6 wk postoperatively. Postmortem analyses included radiography, QCT, microCT, biomechanical testing, scintillation counting, autoradiography, and histology.

RESULTS

Single-dose systemic ZA administration significantly increased callus volume, callus BMC, and mechanical strength. Perioperative treatment increased mechanical strength by 30% compared with controls (p < 0.05). Administering the systemic dose at 1 or 2 wk after fracture further increased mechanical strength compared with controls by 44% and 50%, respectively (p < 0.05). No significant differences in mechanical parameters were seen with local injection at the dose studied. Autoradiographic analysis indicated that ZA binds significantly to bone that is present at the time of administration. ZA quantification indicated that delayed administration significantly increased the uptake efficiency in the callus. Histological and microCT analysis showed that ZA treated calluses had a distinctive internal structure consisting of an intricate network of retained trabecular bone.

CONCLUSIONS

The timing of a single systemic dose of ZA plays an important role in the modulation of callus properties in this rat fracture model; delaying the single dose produces a larger and stronger callus.

Biocompatible nanofiber scaffolds on metal for controlled release and cell colonization

This paper reports for the first time a preparation of biocompatible titanate nanofiber scaffolds on the surface of titanium foil/mesh via a one-step hydrothermal reaction. The length and diameter of the nanofibers can be controlled by varying the fabrication parameters, such as reaction temperature, precursor concentration, and reaction time. The nanofibers can self-organize into macroporous (mostly 0.5-10 microm in diameter) scaffolds potentially useful for developing new bioscaffolds, photocatalysts, sensors, and drug delivery vehicles.

12‐Lipoxygenase‐derived eicosanoids protect against myocardial ischemia/reperfusion injury via activation of neuronal TRPV1

Recent evidence implicates the neuronal transient receptor potential vanilloid receptor 1 (TRPV1), expressed on sensory C-fibers, as playing an important endogenous protective role in limiting the damaging effects of myocardial I/R injury. In neurons the 12-lipoxygenase (12-LOX) arachidonic acid (AA) metabolite, 12(S)-HpETE, has been proposed as the endogenous ligand for TRPV1. However, whether 12(S)-HpETE underlies TRPV1 channel activation during I/R is unknown. Treatment of isolated Langendorff rat hearts with a 12-LOX/AA cocktail significantly attenuated I/R injury (approximately 40% inhibition of infarct size), an effect reversed by the 12-LOX inhibitor baicalein or after chemical desensitization of local sensory C-fiber afferents using capsaicin. Both 12(S)-HpETE and AA caused dose-dependent coronary vasodilatation (approximately EC50s of 6x10(-19) and 1x10(-7), respectively) that was profoundly suppressed by the TRPV1 antagonist capsazepine, in hearts of TRPV1 knockout mice compared with wild-type mice, or by treatment with a CGRP antagonist. In addition, I/R itself stimulates up-regulation of TRPV1 expression in both the cell bodies located within the dorsal root ganglia and locally within the myocardium. Together, our data identify a novel 12-LOX/AA/TRPV1 pathway activated and up-regulated during I/R injury, providing an endogenous damage-limiting mechanism whose targeting may prove useful in treating myocardial infarction.

The same dorsal root ganglion neurons innervate uterus and colon in the rat

The purpose of this study was to determine whether primary sensory neurons that innervate the uterus receive convergent input from the colon. To test this, in the rat, cell bodies of colonic and uterine dorsal root ganglia were retrogradely labeled with fluorescent tracer dyes microinjected into the colon/rectum and bilaterally into the uterine horns. Ganglia were harvested, cryoprotected and cut into 20 microm slices to identify positively stained cells for fluorescent microscopy. Up to 5% of neurons were colon-specific or uterus-specific, and 10-15% of labeled ganglion neurons innervate both viscera in the L1, L2, L6 and S1-S3 levels. These results suggest a novel form of visceral sensory integration in the dorsal root ganglion that may underlie comorbidity of many functional pain syndromes.

An audit of the impact of implementation of a stroke care pathway in an acute teaching hospital

BACKGROUND

In 2002, a survey of stroke management was conducted in our institution benchmarked against the UK National Stroke Audit 2002. The conclusion was that management of stroke patients lacked organised and specialised care. The introduction of a stroke care pathway was recommended.

AIMS

This audit assessed the clinical impact of implementation of a stroke care pathway by the general medical teams in an acute teaching hospital.

METHODS

A random sample of 48/131 patients were surveyed in 2002 compared to 55 consecutive patients admitted with stroke in 2005.

RESULTS

Despite introduction of a stroke care pathway, marked deficits persisted in acute management including delays in brain imaging and aspirin administration, assessment of acute parameters and interdisciplinary care.

CONCLUSIONS

Optimal care of stroke patients cannot be achieved by introducing a stroke care pathway alone. We recommend the urgent establishment of a stroke unit with a specialist consultant-led multidisciplinary stroke team.

Effects of Diethyldithiocarbamate (DETC) on Liver Injury Induced by Ischemia-Reperfusion in Rats

PURPOSE

In organ transplantation, ischemia-reperfusion injury (I/R) is a constant occurrence. Dithiocarbamates, a class of antioxidants, have been reported to inhibit nuclear factor-kappaB (NF-kappaB), a critical transcription factor in the intracellular inflammatory cascade. We studied the effects of diethyldithiocarbamate (DETC) on liver injury induced by I/R.

MATERIALS AND METHODS

Male Wistar rats were pretreated with DETC (100 mg/kg IV) 10 minutes before hepatic ischemia, which was followed by 2 hours reperfusion, or 10 minutes prior to the reperfusion. Blood samples were obtained at the end of the reperfusion period to determine the biochemical markers of liver injury. Results were compared using the one-way analysis of variance (ANOVA), followed by the Bonferroni posttest, and presented as mean values +/- SEM.

RESULTS

I/R produced significant increases in aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (gamma-GT) serum levels compared with sham-operated rats. Administration of DETC prior to the onset of reperfusion significantly reduced the liver injury. However, DETC administered before the ischemic period failed to protect the liver from an I/R injury.

CONCLUSION

DETC, administered just before the reperfusion period, resulted in a significant decrease in the I/R injury to the liver, an observation that may have therapeutic implications.

Recombinant human acid [alpha]-glucosidase: major clinical benefits in infantile-onset Pompe disease

BACKGROUND

Pompe disease is a progressive metabolic neuromuscular disorder resulting from deficiency of lysosomal acid alpha-glucosidase (GAA). Infantile-onset Pompe disease is characterized by cardiomyopathy, respiratory and skeletal muscle weakness, and early death. The safety and efficacy of recombinant human (rh) GAA were evaluated in 18 patients with rapidly progressing infantile-onset Pompe disease.

METHODS

Patients were diagnosed at 6 months of age and younger and exhibited severe GAA deficiency and cardiomyopathy. Patients received IV infusions of rhGAA at 20 mg/kg (n = 9) or 40 mg/kg (n = 9) every other week. Analyses were performed 52 weeks after the last patient was randomized to treatment.

RESULTS

All patients (100%) survived to 18 months of age. A Cox proportional hazards analysis demonstrated that treatment reduced the risk of death by 99%, reduced the risk of death or invasive ventilation by 92%, and reduced the risk of death or any type of ventilation by 88%, as compared to an untreated historical control group. There was no clear advantage of the 40-mg/kg dose with regard to efficacy. Eleven of the 18 patients experienced 164 infusion-associated reactions; all were mild or moderate in intensity.

CONCLUSIONS

Recombinant human acid alpha-glucosidase is safe and effective for treatment of infantile-onset Pompe disease. Eleven patients experienced adverse events related to treatment, but none discontinued. The young age at which these patients initiated therapy may have contributed to their improved response compared to previous trials with recombinant human acid alpha-glucosidase in which patients were older.

Recombinant human erythropoietin protects the liver from hepatic ischemia-reperfusion injury in the rat

Recently, erythropoietin was shown to have both hematopoietic as well as tissue-protective properties. Erythropoietin (EPO) had a protective effect in animal models of cerebral ischemia, mechanical trauma of the nervous system, myocardial infarction, and ischemia-reperfusion (I/R) injury of the kidney. It is not known whether EPO protects the liver against I/R injury. Using a rat model of liver I/R injury, we aimed to determine the effect of the administration of human recombinant erythropoietin (rhEPO) on liver injury. Rats were subjected to 30 min of liver ischemia followed by 2 h of reperfusion. When compared with the sham-operated rats, I/R resulted in significant rises in the serum levels of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, gamma-glutamyl transferase, tissue lipid peroxidation, caspase-3 activity and altered histology. Administration of rhEPO 5 min before ischemia was able to reduce the biochemical evidence of liver injury; however, this protection was not evident when rhEPO was administered 5 min before reperfusion. Mechanistically, early administration of rhEPO was able to reduce the oxidative stress and caspase-3 activation, suggesting the subsequent reduction of apoptosis. This study provides the first evidence that rhEPO causes a substantial reduction of the liver injury induced by I/R in the rat.

Is screening for tuberculosis acceptable to immigrants? A qualitative study

BACKGROUND

Screening of immigrants has been a widespread response to the global resurgence of tuberculosis but has been criticized as discriminatory and stigmatising. Acceptability is an essential but neglected ethical prerequisite of screening programmes, particularly those targeting vulnerable groups such as refugees. No data exist concerning acceptability of tuberculosis screening. We therefore examined the responses of immigrants to screening for tuberculosis in a range of settings.

METHODS

We carried out a qualitative interview study of a maximum diversity sample of 53 immigrants offered screening for tuberculosis in east London. We recruited people screened in three settings: a social service centre for asylum seekers, a hospital clinic for new entrants and primary care. We confirmed validity of our findings at a focus group of asylum seekers.

RESULTS

The opportunity to be screened for tuberculosis was valued highly by recipients. Moreover, many saw being screened as a socially responsible activity. Of the minority raising concerns, few mentioned the possibility of discrimination. Acceptability was high irrespective of setting, with respondents expressing preference for their chosen place of screening.

CONCLUSION

Screening for tuberculosis was highly acceptable to recipients in these settings. Screening should be offered in a range of settings.

A phase II trial to assess the activity of MVA5T4 plus interleukin-2 in patients (Pts) with metastatic renal cell carcinoma (MRCC)

14642

Background: MVA 5T4 consists of a highly attenuated vaccinia virus (modified Vaccinia Ankara, MVA) containing the human tumor associated antigen (TAA) 5T4. Greater than 90% of renal cell cancers are overexpressed by the 5T4 antigen. The primary purpose of this trial is to validate the hypothesis that, in this group of pts, it is possible to induce immune responses either humoral and/or cellular to 5T4 and to break tolerance to the antigen. The immune response will be correlated to clinical outcome. Methods: Eligibility included: pathologic diagnosis of confirmed clear cell or papillary cancer, progressive measurable MRCC, adequate organ/marrow function, Karnofsky Performance Status (KPS) ≥ 80%, any prior therapy, and no active CNS involvement. The dosage schedule of subcutaneous low dose IL-2 will be an initial dose 250,000 U/kg/dose for 5 days in week 1 followed by 125,000 U/kg/dose for 5 days each of weeks 2–6 inclusive. There will then be a 2 week recovery period before the next cycle commences. The dosage regimen of MVA 5T4 will be intramuscular injections given 14 days prior to the first cycle, day 0 and 1 injection given at the beginning of week 4 of the first cycle. In subsequent cycles, booster injections of MVA 5T4 will be given at week 1 only, prior to the commencement of subcutaneous IL-2 therapy. Results: 10 pts have been treated with MVA 5T4 and the LD IL2 regimen. The combination has been extremely well tolerated with no MVA 5T4 related events thus far. Although the study is still continuing to accrue, there are early signs of clinical responses in a number of patients receiving the combination. The immunological analysis is in progress. Conclusion: MVA 5T4 is well tolerated in this group of patients. The immune response will be presented along with clinical outcome.

[Table: see text]