Remarks on the validity of Myxobolus ampullicapsulatus and Myxobolus honghuensis (Myxozoa: Myxosporea) based on SSU rDNA sequences.

In the present study, we isolated three populations of Myxobolus ampullicapsulatus from the gills of crucian carp, Carassius auratus auratus, two from Yongchuan, Chongqing area and one from Poyang Lake, Jiangxi area, China, sequenced their complete small subunit ribosome RNA gene, analyzed their genetic distance and gene similarity, and explored their relationship based on Bayesian inference and maximum likelihood analyses of their small subunit ribosomal DNA. The results combined with their morphological characteristics suggest that M. ampullicapsulatus infecting the gills and pharynx of allogynogenetic gibel carp, Carassius auratus gibelio, should be Myxobolus honghuensis. This study highlights the importance of DNA sequence comparisons for distinguishing Myxobolus species and indicates that the intra-species identification for the two Myxobolus species mentioned in the present research should be less than ten variation sites. In morphology, M. honghuensis Liu et al. (2012) parasitic on the gills of C. auratus auratus (goldfish) was collected from Chongqing area, and its mature spore was 16.5-19.5 × 8.5-10.0 µm in size, polar capsule was 7.0-10.0 × 2.5-4.0 µm in size, and polar filament had 9-10 coils. M. honghuensis Liu et al. (2012) isolated from the pharynx of C. auratus gibelio was sampled in Hubei area, and its mature spore was 15.1-19.5 × 9.0-11.3 µm in size, polar capsule was 7.9-8.1 × 3.0-4.5 µm in size, and polar filament had 7-8 coils.

Effects of electroacupuncture on a degenerated intervertebral disc using an in-vivo rat-tail model.

Electroacupuncture (EA) has long been used as conservative treatment for low back pain (LBP). Its effect on relief of back pain has been demonstrated in many clinical studies. However, whether it has any effect on the biological properties of an intervertebral disc, which is one of the major causes of LBP, is still unclear. The aim of this study was, therefore, to investigate the effects of EA with different simulation frequencies on an intervertebral disc with simulated degeneration using an in-vivo rat-tail model. In this study, 33 rats were used. Disc degeneration was simulated in the rat caudal 8-9 disc via continuous static compressive loading of 11 N for 2 weeks. EA with a frequency of 2 or 100 Hz was then applied to the degenerated disc for 3 weeks with 3 sessions/week and 20 min/session. The intervertebral disc height was measured before and after compression as well as after EA intervention for 3 weeks. The static compression was found to result in a reduction in the disc height of about 22 per cent. There was no evidence that this change could be reversed after resting or the EA intervention. However, EA at 100 Hz was found to induce a further decrease in disc height, which was not shown for the rats after resting or EA at 2 Hz. The results of this study showed that effects of EA on disc degeneration are frequency dependent and adverse effects could result if EA at a certain frequency was used.

Reliability of radiographic intervertebral disc height measurement for in vivo rat-tail model.

Quantification of changes in intervertebral disc height is critical for studying intervertebral disc degeneration. Reliability of disc height measurement is therefore especially important for in vivo studies using animal models of disc degeneration. In this study, the effects of image intensity and percentage of disc width used for disc height measurement from radiographic images were evaluated in a rat-tail model. Radiographs were taken for 10 Sprague-Dawley rats using a standardized protocol. Average disc heights of the caudal 8-9 discs were determined using original and intensity adjusted images with different percentages of disc width. The average disc height was found to be significantly affected by both the image intensity and the percentage of disc width measured. A higher reliability was found in the measurement for image with adjusted intensity and using smaller disc width. Image intensity is suggested to be controlled and the disc width should be taken into account in quantifying the disc height.

International Internet-2 performance and automatic tuning protocol for medical imaging applications.

Internet-2 is an advanced computer network, which has been widely used for medical imaging applications such as teleradiology and teleconsultation, since Internet-2 can fulfill the requirements for high-speed data transmission and short turn-around time with low operation cost once installed. However, such high performance of Internet-2 may not be retained for global access from international network peers. Considering the international Internet-2 connection between the PolyU and the IPI/USC, there exist two major factors, network looping in the US and bottleneck of the connection, raising the round-trip time and limiting the available bandwidth, respectively. The available bandwidth will be further underutilized if the TCP/IP parameters at the sending and receiving computers are not appropriately chosen. This paper proposes a repeatable and consistent protocol to automatically tune these parameters for the clinical applications.

Monte Carlo simulation of x-ray spectra in mammography.

A model for generating x-ray spectra in mammography is presented. This model used the ITS version 3 Monte Carlo code for simulating the radiation transport. Various target/filter combinations such as tungsten/aluminium, molybdenum/molybdenum, molybdenum/rhodium and rhodium/rhodium were used in the simulation. Both bremsstrahlung and characteristic x-ray production were included in the model. The simulated x-ray emission spectra were compared with two sets of spectra, those of Boone et al (1997 Med. Phys. 24 1863-74) and IPEM report 78. The chi2 test was used for the overall goodness of fit of the spectral data. There is good agreement between the simulated x-ray spectra and the comparison spectra as the test yielded a probability value of nearly 1. When the transmitted x-ray spectra for specific target/filter combinations were generated and compared with a measured molybdenum/rhodium spectrum and spectra generated in IPEM report 78, close agreement is also observed. This was demonstrated by the probability value for the chi2 test being almost 1 for all the cases. However, minor differences between the simulated spectra and the 'standard' ones are observed.

Adhesion formation after nerve repair: an experimental study of early protected mobilization in the rabbit.

The common peroneal nerve and its surrounding muscles were cut and repaired in 14 rabbits. The injured limb was then either immobilized for 3 weeks or passively mobilized within a "safety range" every day. At 3 weeks after operation, the "stretch test" and "peel test" showed no difference in the biomechanical features of the adhesions between the nerve repair and the surrounding soft tissues.

Effects of static compression with different loading magnitudes and durations on the intervertebral disc: an in vivo rat-tail study.

STUDY DESIGN: An in vivo rat-tail model was used to study the effects of static compression with different loading magnitudes and durations on the intervertebral disc. OBJECTIVE: To investigate the effects of static compression with different loading magnitudes and durations on the intervertebral disc over a period of time. SUMMARY OF BACKGROUND DATA: A disc degeneration model is essential for studying therapeutic effects on degenerated disc. Static compression can induce degenerative-like changes in the intervertebral disc. However, the consequences of the simulation model over a period of resting have not been clearly documented, which may have confounding effects on the experimental outcome. METHODS: Thirty-five rats were used. Static compressions with different loads (11 or 17 N) and durations (1 hour daily or continuous) were applied to the rat-tail caudal 8-9 disc for 2 weeks, and followed with 3 weeks of rest. The disc height was quantified in vivo on days 4, 18, and 39. The rats were killed and the discs were harvested for morphologic examination on day 39 after the disc height measurement. RESULTS: Significant decrease in disc height was observed after continuous static compression for both 11 and 17 N, and continued during the resting period. The morphologic evaluation of the continuous compressed disc showed a decreased nuclear size, reduced number of nuclear cells, and irregular nuclear shape with inward bulging of disorganized annular collagen lamellas. Daily compression of 1 hour was found to induce a transient increase in disc height, but restored after the 3-week resting period. Favorable morphologic changes, including vacuolated nuclear cells and oval nuclear shape with well-organized annular collagen lamellas, were seen in the rat disc specimens with daily compression of 1 hour. CONCLUSION: Disc degenerative-like changes without recovery were demonstrated in the rat caudal disc after continuous compression. The changes in disc height and disc morphology were found to be dependent on the duration of load application and may have clinical implication.