Website discussion forums: results of an Australian project to promote telecommunication in dermatology

Discussion forums on the Internet allow doctors to discuss issues of interest in a rapid, convenient and educational manner. In March 2002, the department of dermatology at the St George Hospital in Sydney launched a national Website with an online discussion forum for dermatologists. Features of the Website forum include the ability to moderate the discussion boards, a choice of public or private discussions and receipt of automatic email notifications. Over three months, three dermatologists posted a total of 13 messages on three different topics. The low rate of participation by dermatologists may have been due to lack of time or familiarity with the technology. Increased promotion to and education of dermatologists who are most likely to use the discussion forum may improve utilization of this means of communication.     

Severe amphethamine-induced bruxism: treatment with botulinum toxin

While chewing and grinding movements have been observed in amphetamine addicts, recognition and management of this problem have rarely been highlighted. Botulinum toxin (BTX) has previously been demonstrated to be effective for bruxism associated with movement disorders, such as cranial-cervical dystonia. However, there is little information on its use in tardive bruxism. Here we report an amphetamine addict who presented with medically intractable bruxism, and discuss its pathophysiology and successful treatment with BTX.     

Conditioned stimulus-induced reinstatement of extinguished cocaine seeking in C57BL/6 mice: a mouse model of drug relapse

The scarcity of mouse models for relapse to cocaine seeking has curtailed the study of genetic factors that may contribute to susceptibility for drug relapse. To contribute to the development of a new mouse model of drug relapse, C57BL/6 (B6) mice were trained to press a lever for infusions of cocaine (0.35 mg/kg, i.v.) on a fixed ratio 1 schedule of reinforcement during daily 2-h sessions. A light+tone stimulus complex was presented simultaneously with each cocaine infusion. Mice then underwent a series of extinction sessions during which lever presses had no scheduled consequences. As a result, lever pressing gradually declined. In experiment 1, the ability of the cocaine-paired light+tone stimulus complex to reinstate extinguished cocaine-seeking behavior (i.e. non-reinforced responses) was assessed. In experiment 2, the ability of cocaine priming (0, 1, 2.5, 5, 10, 20, and 40 mg/kg, i.p.) to reinstate cocaine-seeking behavior was measured. B6 mice failed to reinstate in response to i.p. cocaine priming; however, they exhibited robust conditioned stimulus-induced reinstatement. These findings suggest that conditioned stimulus-induced reinstatement in B6 mice is a promising model to study genetic and neurobiological factors that alter the ability of cocaine-paired stimuli to elicit relapse to cocaine seeking behavior.     

Epidemiology and pathogenesis of scleroderma

Scleroderma is a heterogenous connective tissue disorder characterized by fibrosis of the skin, with or without internal organ involvement. The aetiology of scleroderma may involve both environmental and genetic factors. Abnormalities involving the immune system, vascular tissue and extracellular matrix have been demonstrated. Recent research has focused on microchimerism as a risk factor for the development of scleroderma. This article reviews the epidemiology and pathogenesis of this disorder.     

Combined angiotensin and endothelin receptor blockade attenuates adverse cardiac remodeling post-myocardial infarction in the rat: possible role of transforming growth factor beta(1)

A. Tzanidis, S. Lim, R. D. Hannan, F. See, A. M. Ugoni and H. Krum. Combined Angiotensin and Endothelin Receptor Blockade Attenuates Adverse Cardiac Remodeling Post-Myocardial Infarction in the Rat: Possible Role of Transforming Growth Factor beta(1). Journal of Molecular and Cellular Cardiology (2001) 33, 969-981. Myocardial infarction (MI) is associated with activation of the vasoconstrictor peptides, angiotensin II (AngII) and endothelin-1 (ET-1), which are thought to contribute to adverse cardiac remodeling and dysfunction. The present study sought to determine whether combined AngII and ET receptor blockade improves cardiac remodeling over individual treatments in an experimental model of left ventricular myocardial infarction (LVMI) in the rat. Groups of eight female Sprague-Dawley rats were randomized at 24 h post-LVMI to 1 week treatment with either vehicle, an ET(A/B)receptor antagonist (bosentan), an AT(1)receptor antagonist (valsartan), or combined treatment. Vehicle-treated animals developed LV dysfunction with extensive accumulation of collagen type I and increased alpha(1)(I) procollagen mRNA compared to sham controls. Whilst individual receptor blockade with either bosentan or valsartan reduced LVEDP towards sham control levels, there were no significant changes to myocardial collagen deposition in comparison to vehicle. In contrast, improved ventricular function by combined treatment was associated with reduced type I collagen deposition within left ventricular non-infarct regions, as well as reduced peptide distribution and cardiac gene expression of the profibrogenic peptide, transforming growth factor beta(1)(TGF beta(1)). These data demonstrate that combined AngII and ET receptor blockade has beneficial effects on myocardial fibrogenesis over individual treatments during adverse cardiac remodeling early post-MI.     

Evaluation of gene transfer efficiency by viral vectors to murine bladder epithelium

PURPOSE: In pre-clinical gene therapy studies of bladder cancer there is tremendous variation in the ability of viral vectors to deliver genetic material to bladder epithelium. Possible explanations for this variability may involve the physical parameters of delivering vectors in these experimental models. We examined the effects of intravesical volume and pressure during instillation as well as chemical modification of the bladder epithelium on subsequent gene expression in the bladder in mice. MATERIALS AND METHODS: Female C57B1/6 mice underwent intravesical instillation of the replication restricted canarypox virus (ALVAC) recombinant for the reporter genes luciferase or beta-galactosidase. Similar viral titers were instilled at different volumes and a pressure transducer measured intravesical pressure when the vector was instilled. Also, various agents, including 0.6 N hydrochloric acid, 0.4% oxychlorosene, poly-L-lysine and 0.25 M. ammonium chloride, were used to modify the bladder surface before vector instillation and then assayed for transgene expression. RESULTS: As expected, maximum intravesical pressure measured during instillation was significantly greater in mice instilled with a higher volume (33.1 versus 9.8 mm. Hg). Significantly more gene expression was detected in bladders instilled with a higher volume of viral vectors (p <0.05). Likewise, higher instillation pressures resulted in higher transgene expression in distant organs. Modification of the bladder epithelium with agents such as oxychlorosene and poly-L-lysine resulted in elevated gene expression with only minimal increases in systemic activity. CONCLUSIONS: Significant differences in gene expression are achieved by varying physical parameters during intravesical instillation. Increased gene expression associated with larger volume instillation may be responsible for some reported variability of gene transfer to the bladder. Alternate manipulations, such as modifying the bladder surface, may be done to enhance gene transfer to the urothelium without increasing systemic distribution.     

Intracorporeal needle breakage: an unusual complication of papaverine injection therapy for impotence.

We report an unusual complication of papaverine injection therapy for impotence. After 2.5 years of uneventful injections excessive syringe manipulation following needle insertion resulted in needle breakage and a retained intracavernous needle fragment requiring surgical extraction. A synopsis of the presentation, diagnosis and therapy is presented.