Olfactory ensheathing cells in the nasal mucosa of the rat and human

Olfactory ensheathing cells are unique glial cells which have the ability to encourage nerve fibres to grow, and may have potential for use as a therapy for spinal cord and brachial plexus injuries. These images show olfactory ensheathing cells in the olfactory mucosa of the nose, and provide insight into their function. The olfactory mucosa is likely to be a convenient source for these cells in future clinical studies of CNS repair.

Adjacent segment disease after fusion for cervical spondylosis; myth or reality?

Cervical spondylosis is a common cause of radiculopathy and myelopathy, often treated by discectomy and interbody fusion. However, there has been a recent vogue for the use of artificial disc prostheses to decrease the risk of accelerated degenerative disease at adjacent levels. The short-term results of artificial disc replacements have been encouraging, but the long-term justification for using this new technology hinges on whether the incidence of adjacent segment disease decreases. It will also be necessary to demonstrate that movement at the operated levels is maintained and the incidence of device failure is low. We review the radiological, biomechanical and clinical evidence for adjacent segment disease, and the rationale for using artificial cervical disc replacements. There is presently insufficient evidence to justify the widespread use of artificial disc replacements in the treatment of cervical spondylosis, but neither is there sufficient evidence to criticize their use. Present evidence suggests that adjacent segment disease is partly due to the natural history of spondylotic disease and partly due to cervical fusion. Randomized trials are required to ascertain whether the incidence of adjacent segment disease changes with the use of artificial disc replacements in the long term. Indications for the use of artificial discs are presently unclear, but disc replacements might be recommended for 'young' patients who require an anterior cervical discectomy, with good ranges of neck movements, and an awareness of the satisfactory short-term results, but lack of long-term outcome data, preferably within the limits of a clinical trial.

Left ventricular diastolic functional reserve during exercise in patients with impaired myocardial relaxation at rest

BACKGROUND

Patients with similar grade diastolic dysfunction at rest may have a spectrum of alterations in diastolic function during exercise.

OBJECTIVE

To evaluate (a) whether exercise could unmask further diastolic abnormalities not evident during rest; (b) whether diastolic functional reserve during exercise is associated with exercise capacity.

METHODS

141 subjects (77 male, mean (SD) age 62 (9)) with abnormal left ventricular (LV) relaxation (mitral E/A <0.75) and/or deceleration time >240 ms, underwent graded supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. Mitral inflow and annular velocities were measured at rest and during exercise. The LV diastolic function reserve index (DFRI) was calculated.

RESULTS

Patients were classified into two groups: group 1 (n = 64), DFRI <13.5; group 2 (n = 77), DFRI >or=13.5. The ratio of E/E' to stroke volume was used as an index of ventricular elastance (Ed). No significant differences between the groups in mitral inflow and annular velocities at rest were found. Mean (SD) Ed was not significantly different at rest between the groups (0.19 (0.07) vs 0.18 (0.06), p = 0.29). Ed was significantly higher during exercise in group 1 than in group 2 (25 W, 0.21 (0.09) vs 0.14 (0.04), p<0.001; 50 W, 0.22 (0.10) vs 0.15 (0.04), p<0.001). Group 1 subjects had a shorter exercise duration (8.2 (2.7) vs 9.4 (3.7) min, p = 0.04) and lower peak oxygen consumption (17.5 (4.5) vs 20.2 (5.4) ml/kg/min, p = 0.005).

CONCLUSIONS

Despite similar mitral flow and annular velocities at rest, different responses to exercise were seen in patients with abnormal LV relaxation at rest. Lower LV diastolic functional reserve was associated with higher ventricular elastance during exercise, and reduced exercise capacity.

Clinical studies in spinal cord injury: moving towards successful trials

Spinal cord injury is a devastating condition for which there is still no cure. Many new therapies have emerged in the past few decades that have attempted to improve the outcome after injury, with varying levels of supporting experimental and clinical data. Most studies have been preliminary and have lacked control groups, but positive results can often be embraced by clinicians and patients who are faced without an alternative, despite the poor design and bias of many studies. This article is a review of clinical studies in spinal cord injury and discusses guidelines for future clinical trial design.

Sandwich capture ELISA by a murine monoclonal antibody against a genus-specific LPS epitope for the detection of different common serotypes of salmonellas

A sandwich capture ELISA based on a murine monoclonal antibody against a genus-specific epitope in the outer core region of the Salmonella lipopolysaccharide is described for the detection of different common serotypes of salmonellas. Four h broth cultures of seven standard and 24 wild strains of salmonellas were all detected by the capture ELISA while overnight broth cultures of 21 non-salmonella standard strains were all negative. The capture ELISA detected 1 ng/ml of Ra lipopolysaccharide, 10(6)/ml of a smooth wild strain of Salm. typhimurium, and 1120 cells of Salm. heidelberg after enrichment culture for 4 h.

Determining the cost of tuberculosis case management in a low-incidence state

OBJECTIVE

To establish the average cost per patient of nurse case management for tuberculosis (TB) in Oregon State and so facilitate estimates of the overall cost of TB treatment. TB treatment is currently funded by a combination of local, state and federal public health dollars.

DESIGN

A longitudinal survey was used to assess the amount of case management time patients required per week. Additional patient information was collected from public health records. Mixed effects modeling techniques were used to identify important factors associated with case management time and to make predictions.

RESULTS

The following variables were significantly associated with case management time: non-adherence to treatment, the use of incentives, the phase of treatment and the presence of complicating factors, including human immunodeficiency virus infection, antibiotic resistance, homelessness and adverse reaction to drugs. The mean case management cost was $4831 per patient for a standard 28-week treatment course, and ranged from $3386 for a simple case to $7542 for a case with multiple complications.

CONCLUSIONS

These estimates are substantially higher than the current state funding for case management. Using these data, health officials can make better informed budget decisions and provide more appropriate support for TB control.

Systems biology of the neurospora biological clock

A major challenge of systems biology is explaining complex traits, such as the biological clock, in terms of the kinetics of macromolecules. The clock poses at least four challenges for systems biology: (i) identifying the genetic network to explain the clock mechanism quantitatively; (ii) specifying the clock's functional connection to a thousand or more genes and their products in the genome; (iii) explaining the clock's response to light and other environmental cues; and (iv) explaining how the clock's genetic network evolves. Here, the authors illustrate an approach to these problems by fitting an ensemble of genetic networks to microarray data derived from oligonucleotide arrays with approximately all 11 000 Neurospora crassa genes represented. A promising genetic network for the clock mechanism is identified.

Prohibitin interacts with RNF2 and regulates E2F1 function via dual pathways

Prohibitin, a tumor suppresser protein, plays an important role in the transcriptional regulation of various genes involved in cell-cycle control and proliferation. Recent studies have reported that the growth-suppressive property of the prohibitin protein is exhibited in its physical interaction with E2F family proteins and its subsequent repression of their transcriptional activity. Herein, we report that prohibitin interacts with RING finger protein 2 (RNF2), a member of the PcG (polycomb-group) family of proteins, and that the two proteins regulate the activity of E2F1 via dual pathways: the direct, prohibitin-mediated pathway and the indirect, p16-mediated pathway of E2F1 transcriptional regulation. Co-immunoprecipitation experiments showed that endogenous prohibitin interacts with endogenous RNF2. Interestingly, the expressed amounts of RNF2 and prohibitin were interdependently affected at the post-translational level. Furthermore, the depletion of either endogenous RNF2 or prohibitin using the RNA interference technique increased the level of p16 protein expression, resulting in a decrease in the transcriptional activity of E2F1 via the p16-CDK4-Rb pathway. In addition, chromatin immunoprecipitation assays showed that RNF2 was recruited to E2F1-response promoters along with prohibitin to inhibit the transcriptional activity of E2F1. Cell proliferation was also regulated by the prohibitin-RNF2 interaction. These results suggest that the RNF2-prohibitin complex regulates the activity of E2F1 via dual pathways.

Hepatic intra-arterial injection of 3-bromopyruvate in rabbit VX2 tumor

PURPOSE

To evaluate the antitumoral effects of an intra-arterial injection of 3-bromopyruvate (3-BrPA) on liver VX2 tumor in rabbits.

MATERIAL AND METHODS

Twenty rabbits with surgically implanted liver VX2 tumors were used. The rabbits were divided into three groups: a control, a saline, and a 3-BrPA group. Four rabbits were not treated at all, and they served as the control group. The saline group (n = 6) received only intra-arterial saline injection. The 3-BrPA group (n = 10) received an intra-arterial injection of 3-bromopyruvate through the hepatic artery. The delivered amounts of 3-bromopyruvate were as follows: 25 ml of 0.5 mM in six rabbits, 25 ml of 1.0 mM in two rabbits, and 25 ml of 2.0 mM in two rabbits. Four days after intra-arterial injection, the rabbits were sacrificed and histopathologic analysis of the explanted livers was performed with comparison of the tumor necrosis ratio (a percentage of the necrotic area versus the entire tumorous area) in each group.

RESULTS

The mean tumor necrosis ratio was 12.5+/-4.2%, 44.8+/-24.7%, and 49.4+/-14.3% in the control, saline, and 3-BrPA groups, respectively. Between the control and the saline group, and between the control and the 3-BrPA group the mean tumor necrosis ratio appeared to be significantly different (P<0.05). However, there was no statistical difference in the mean tumor necrosis ratio between the saline and the 3-BrPA group (P = 0.416).

CONCLUSION

A single session of intra-arterial injection of 3-BrPA showed no better results in terms of tumor necrosis than that of saline injection in a rabbit VX2 tumor model.

Transport of living cells with magnetically assembled nanowires

We present a technique of transporting and positioning living cells internalized by nickel (Ni) nanowires guided by magnetic field. Nanoscale magnetic nanowires are internalized by the Rat Neuroblastoma (ATCC number CRL-2754) and the cells are transported and positioned by magnetic fields from the magnetic material-coated electrodes. This technique may enable the interfacing between neurons and electronic devices to empower investigations pertaining to non-invasive neuron probing as well as nanofabricated neural pharmacological technologies.

Tissue factor serum levels and the risk of future coronary artery disease in apparently healthy men and women: the EPIC-Norfolk prospective population study

INTRODUCTION

Tissue factor (TF) has been implicated in coronary artery disease (CAD). High levels of circulating TF are found in patients with acute atherothrombotic events. Whether high serum TF levels predict risk of future CAD independent of known risk factors remains unknown.

METHODS

We conducted a prospective case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk population study. Cases (n=1037) were apparently healthy men and women, aged 45-79 years, who developed fatal or non-fatal CAD during follow-up. Controls (n=2005) were matched by age, sex, and enrolment time. Serum TF levels were measured using high-affinity antibodies.

RESULTS

In men, median TF levels were not significant higher in cases than in controls (59.0 pg mL-1, range: 16.7-370.4 vs. 54.9 pg mL-1, range: 16.2-452.4). In women, median TF levels were not significant higher in controls than in cases (73.4 pg mL-1, range: 16.7-492.3 vs. 50.5 pg mL-1, range: 16.5-376.7). The incidence of smoking was about double in the lowest compared with the highest TF quartile. Correcting for sex, age, body mass index, smoking, diabetes, systolic blood pressure, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and C-reactive protein levels, the risk of future CAD was 1.05 (95% CI: 0.81-1.36) for people in the highest TF quartile, compared with those in the lowest (P-value for linearity=0.8).

CONCLUSION

High levels of serum TF were not independently associated with an increased risk of future CAD in apparently healthy individuals.