Herpes simplex virus vector-mediated expression of Bcl-2 protects spinal motor neurons from degeneration following root avulsion

Proximal axotomy in adult animals results in delayed death of motor neurons. Features characteristic of both necrosis and apoptosis have been described in motor neurons of the spinal cord following proximal avulsion of the ventral roots. We have previously demonstrated that a genomic herpes simplex virus (HSV)-based vector expressing the anti-apoptotic peptide Bcl-2 protects dopaminergic neurons of the substantia nigra from neurotoxin-induced apoptotic cell death and preserves the neurotransmitter phenotype of those cells. In this study we examined whether the same vector could protect adult rat lumbar motor neurons from cell death following proximal ventral root avulsion. Injection of the Bcl-2-expressing vector 1 week prior to root avulsion increased the survival of lesioned motor neurons, determined by retrograde Fluorogold labeling, by 50%. The Bcl-2-expressing vector did not preserve choline acetyltransferase neurotransmitter phenotype of the lesioned cells. These results shed light on the mechanism of cell death following axonal injury, and have implications for developing an effective treatment for the clinical problem of proximal root avulsion.     

Survey of Australian and New Zealand Oral and Maxillofacial Surgery trainees and recent specialists--workforce issues

This study examined Oral and Maxillofacial Surgeon (OMS) workforce issues in relation to current training in Australia and New Zealand. Earlier findings identified that there was a requirement of approximately 6 additional OMS specialists per year in Australia and one per year in New Zealand to maintain an adequate level of supply in the profession. It was found in this study that through to the early part of the next decade the number of OMS entering the Australian workforce is appropriate (5.9 per annum), but there would appear to be concerns about the sufficiency of the number entering the New Zealand workforce (0.7 per annum). In addition, the study also found possible maldistribution in the location of intended future practices, with possible shortages outside of the metropolitan areas.     

Retinal-image mediated ocular growth as a mechanism for juvenile onset myopia and for emmetropization

The very common ocular clinical ocular condition in children juvenile onset myopia results from axial elongation of the eye. In humans, some studies have found an association of myopia with greater levels of nearpoint activity and with differences in accommodation and convergence function. This paper reviews a variety of laboratory and clinical studies which are consistent with the hypothesis that retinal image defocus is biochemically transformed into an axial elongation expressed through increased posterior segment growth, and thus myopia. This paper also reviews theories of emmetropization, and classifies them as correlational, feedback, and combination. Evidence is presented to suggest that a combination theory, which combines both correlation of the ocular dioptric components and some feedback mechanism for growth of the eye, is the most correct. Current laboratory research suggests that quality and/or focus (defocus) of retinal imagery is involved in this feedback mechanism and that experimentally induced myopia might be enhanced, reduced or eliminated by pharmaceutical application. Direction of defocus may affect the rate of posterior segment growth, and thus the rate of ocular axial elongation.     

The reaction of edentulous oral mucosa to prolonged denture retention

A bstract — Pre- and post-treatment biopsies were obtained from the maxillary palatal alveolus of ten patients who had dentures wired-in for long periods (median 32 weeks) as part of the jaw immobilization apparatus to limit eating in obese patients. Histological sections were examined in a random, masked manner, and assessed for evidence of inflammatory change. Four showed increased inflammatory change and four decreased inflammatory changes. Correlation was not observed between type of inflammatory change, duration of fixation, age and health of the patient contrary to expectations for prolonged and continuous denture wearing in unhealthy patients.     

Prostaglandin E2 production during hepatic regeneration downregulates Kupffer cell IL-6 production.

The liver possesses the remarkable ability to regenerate to its original size after a 70% partial hepatectomy. There has been little effort to characterize the Kupffer cells' role in this unique mammalian reparative physiologic phenomenon. The capacity of rat Kupffer cells (KC) isolated at specific intervals after partial hepatectomy to produce interleukin-6 (IL-6) and prostaglandin E2 (PGE2) in response to endotoxin was evaluated in standard RPMI-1640 (1200 microM L-arginine) and arginine-depleted RPMI-1640 (10 microM L-arginine) media. Regenerating liver KC 48 to 120 hours after partial hepatectomy responded to endotoxin stimulation with a significantly greater (p less than 0.05) production of IL-6 in standard RPMI-1640. Because Kupffer cells function in an environment where high arginase activity results in negligible L-arginine levels, the 10 microM L-arginine RPMI-1640 was used to simulate the true hepatic microenvironment. Production of IL-6 by regenerating liver KC was further increased (p less than 0.05) by placing these same KC in 10 microM L-arginine RPMI-1640 tissue culture media. During the same period, regenerating liver KC produced significantly (p less than 0.01) more PGE2 than sham-operated KC in both standard and low-arginine media. When the cyclo-oxygenase inhibitor indomethacin (1 x 10(-5) M) was added to cultures, the PGE2 production was inhibited, and IL-6 production was upregulated (p less than 0.05) in arginine-depleted cultures. The authors conclude that during hepatic regeneration KC IL-6 production is elevated but controlled in an autoregulatory fashion by KC PGE2 production.     

INFERENTIAL THERAPY TO PROMOTE UNION OF MANDIBULAR FRACTURES

Non-union of mandibular fractures is uncommon, but when it does occur it requires protracted treatment including further surgery. Nine patients with factors known to predispose to non-union out of 150 consecutive mandibular fractures received interferential therapy (I.T.) during the fixation period; all fractures united satisfactorily. In a retrospective study of 150 consecutive mandibular fractures previously treated by the same surgeons without I. T., three fractures resulted in non-union requiring grafting. Thus the incidence of non-union was 0% when I. T. was used and 2% in the control group.