Long-term measurement of muscle function in the dog hindlimb using a new apparatus

The objective of this study was to develop an apparatus for reliable, reproducible, and minimally invasive measurements of long-term, myoneural function. Twenty conditioned dogs were anesthetized and placed supine with one hindlimb secured in a boot apparatus. The hindpaw was attached to a force transducer that was connected to a recorder for continuous monitoring of torque. Muscles within the anterolateral compartment were stimulated by percutaneous electrodes over the peroneal nerve near the fibular head. This elicited isometric dorsiflexion of the hindpaw. Twitch and tetanic torques correlated positively with dog weight whereas other skeletal-muscle function parameters (time to peak tension, one-half relaxation time, and endurance) were independent of dog weight. Muscle function results were consistent with an overall compartmental composition of 30% Type I and 70% Type II fibers. Repetitive testing of twitch and tetanic torques in the dog legs yielded coefficients of variance of 3-4% (intraday) and 7% (interday). Thus, about one-half of the interday variability may be accounted for by diet, exercise, and other physiological conditions that change daily. The apparatus was also used to detect myoneural degeneration following tourniquet ischemia. The results indicate that this procedure for evaluating muscle function yields reliable and quantitative results noninvasively, and thus allows long-term testing of muscle function in normal and diseased hindlimbs of dogs.     

Comparison of stainless steel and composite plates in the healing of diaphyseal osteotomies of the dog radius: report on a short term study.

The rigid fixation of fractures is generally accepted as the best method to achieve union when open treatment of a fracture is undertaken. This has led to the development of plates that have a greater overall dimension and stiffness compared to earlier plate models, as exemplified by the Lane or Eggers type of plate. In our experience the more rigid plate generally leads to satisfactory union, but also carries with it the risk of refracture, either through a screw hole or across the original fracture after plate removal. Experiments by Uhtoff and Dubuc on experimental animals showed that plate induced osteopenia existed when a rigid plate was applied to an intact or osteomized canine femur. These results provide a possible explanation for the occurrence of late fracture. The study to be described is based on the hypothesis that a rigid plate applied to bone induced localized immobilization osteopenia, which ultimately weakens the bone and leads to the development of late fracture. The study was designed to compare a plate made of stainless steel, which exhibited mechanical stiffness comparable to that of devices presently in use, with a plate made of a composite material, which exhibited decreased stiffness by nearly one order of magnitude. It had been demonstrated by engineering analysis that the less stiff plate would allow the bone to experience normal loading, and it was thought that this loading would modulate the rate and pattern of bone remodeling, thereby resulting in bone of greater strength and size as compared to a more rigidly plated bone.     

Monoclonal antibody binding to brain membranes is altered by iodonitrotetrazolium violet treatment

Treatment of brain membrane preparations with para-iodonitrotetrazolium violet, used in preparing synaptic plasma membranes and related fractions, can either increase or decrease monoclonal antibody binding to the membranes. Thus, statements about the absolute amount of antigen present in such fractions cannot be made solely on the basis of antibody binding studies. However, such preparations remain useful as targets for monoclonal antibody screens, and in assays to determine the relative distribution of an antigen. For example, the G5 rat nervous system specific antigen can tentatively be considered a minor, developmentally regulated component of the extra-junctional portion of synaptic plasma membranes.     

Evaluation of Suspected Monoclonal Gammopathies: Experience in a Tertiary Care Hospital

Background

Monoclonal gammopathies occurs in patients with malignant diseases of plasma cells and lymphocytes and in few benign conditions. The objective of this study was to assess the precision, accuracy and confirmation of monoclonal gammopathies on serum protein electrophoresis (SPE) and the clinical relevance of detection and characterization of M component.

Methods

All samples received for serum electrophoresis in the last 3 years were analysed for data on M band positivity and correlating it with clinical profile of the patients. Immunofixation (IFE), Immunoelectrophoresis (IEP) and IgG, IgM estimation were carried out in few cases. The follow up of cases was done by serial monitoring of SPE and β₂ microglobulin levels.

Results

1155 samples were received during the 3 years period. 282 (24.4%) samples were positive for M component on SPE. Of these, 239 (84.8%) patients had M spike in λ region and 43 patients had M spike in β region. The mean load of the M protein band in the λ region was 37.8% and in β region was 35.8%. IgG with κ chain was seen in 40%, IgG with λ chain was seen in 50%, 5% patients each had IgM with κ and IgA with λ light chain. 246 samples (96.5%) had high levels of β₂ microglobulin. Of the 116 cases of multiple myeloma, IgG levels was more commonly raised (5%) as compared to IgA (6.9%) and IgM (5.2%).

Conclusion

It is recommended that SPE should be performed in patients having unexplained weakness, anaemia, back pain, osteoporosis, osteolytic lesions, fractures, renal insufficiency or recurrent infections.Key Words: Serum protein, Electrophoresis, M band, Multiple myeloma     

Cervical Disc Replacement for Spondylotic Myeloradiculopathy

Background

Cervical disc replacement is a newer concept and rapidly developing surgical treatment. A prospective study was conducted to determine, if accurately implanted Bryan''s cervical disc prostheses can provide relief from objective neurological symptoms and signs, stability and normal range of motion in cases of cervical disc prolapse with myeloradiculopathy.

Material and Method

Twenty patients underwent Bryan cervical disc replacement from Jan 2002 to Dec 2003. Young patients between age groups 21 to 50 years with degenerative cervical disc prolapse at C3-C7 with myeloradiculopathy were included in this study. Patients with significant facet joint arthropathy, unstable spine, trauma, tumour, osteoporosis and active infection were excluded from this study. Nurick''s grading was used for quantifying the neurological deficit. Patients were operated by anterior cervical approach using a specially designed Bryan''s cervical discectomy system. Neurological and radiological outcome was assessed post operatively and at 2,6,12 and 24 months follow up. Outcome analysis was carried out using modified Odom''s criteria. The radiographic results were assessed by taking antero posterior (AP) and lateral radiographs of cervical spine to find range of motion and device position.

Results

The patients were in the age group of 31 to 50 years. There were 14 (70%) male and 6 (30%) female in this study. Neck pain and brachialgia were the presenting symptoms in all cases, 12 (60%) had radiculopathy and 8 (40%) had myelopathy. Single level disc prolapse was present as per Magnetic Resonance Imaging (MRI) in four (20%) at C4-C5, 12 (60%) at C5-C6 and 4 (20%) at C6-C7. Bryan''s disc size 15 was used in 8 (40%) and size 17 was used in 12(60%) patients. During post-operative, 02, 06, 12, and 24 months follow up, the clinical outcome was excellent in 16 (80%) and good in 4 (20%) as per modified Odom''s criteria. There was demonstrated improvement in flexion, extension and rotation clinically and radiologically during follow up. There was no migration or displacement of device.

Conclusion

Cervical disc replacement for cervical disc prolapse with myeloradiculopathy represents an exciting new technology. Patients treated with the Bryan cervical disc prosthesis for single level cervical disc prolapse showed good to excellent improvement in neurological deficit. Clinically and radiologically maintenance of motion was found during follow up. More patients with longer follow up and post operative MRI to find out the protection to adjacent discs from abnormal stress will be required before this prosthesis is accepted as a treatment option.Key Words: Spondylotic myeloradiculopathy, Cervical disc replacement     

A new antigen common to the rat nervous and immune systems: I. Detection with a hybridoma

An antibody secreting cell line has been obtained using the technology developed by Milstein, Kohler, and colleagues by fusion between ×63 myeloma cells and spleen cells from a mouse previously immunized with PC12 cultured rat pheochromocytoma cells. This antibody bound to particulate protein from adult rat brain and to a lesser extent spinal cord and retina but not adrenal. Lower levels of binding were observed also with spleen, bone marrow, and peritoneal exudate cells. Cells or particulate protein from seven nonneural, nonimmune tissues showed essentially no specific binding. Analysis of adherent and nonadherent peritoneal exudate cells indicated specific antibody binding to both populations. The specific antibody bound was greater in the non-adherent fraction. The antigen has been provisionally named G5 after the antibody secreting clone. Like the Thy 1 antigen of rodents, it is expressed by subpopulation of cells from the nervous and immune systems. However the antigen could not be detected on the PC1 2 cell line used for immunization suggesting that Balb/C mice spontaneously produce antibody to this rat differentiation antigen.