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T E Novak

Publications and source records attributed to T E Novak.

3 recordsLinked to original sources

Combined intralesional interferon alpha 2B and oral vitamin E in the treatment of Peyronie's disease.

It has been recently reported that intralesional therapy with alpha interferon 2B resulted in significant improvement of both objective and subjective complaints (penile curvature, pain, plaque size, sexual function) associated with Peyronie's disease. Vitamin E, with its antioxidant properties, may play a role in reducing the inflammatory response. This study was designed to determine the safety and effectiveness of a high dose of alpha INF-2B injected weekly into the Peyronie's plaque combined with oral Vitamin E therapy. Twenty-nine patients with Peyronie's disease were evaluated with penile duplex Doppler for degree of penile curvature, deformity, and plaque size both prior to and after treatment. Each patient then received 4.0 x 10(6) units of alpha INF-2B in 10 cc of normal saline after appropriate local anesthesia. Injections were given once per week directly into the Peyronie's plaque for a period of 10 weeks. Patients also received 400 units of Vitamin E by mouth twice a day. Subjective data was obtained via a questionnaire prior to and at the conclusion of the study. Preliminary results demonstrated improvement of penile curvature in 39% of patients, with one patient experiencing complete resolution. Significant decreases in plaque sizes were noted in 11 of these patients, with softening of the plaques noted in all patients completing the study. Seven patients dropped out of the study prior to completing the 10 weeks: three with severe disease proceeded to surgery, two were lost to follow-up, one had exascerbation of his arthritis symptoms, and one quit secondary to flu-like symptoms. Subjective data from questionnaires revealed improvement in sexual function in those men with decreased curvature and plaque size. Weekly intralesional injections with 4.0 x 10(6) units improved plaque consistency and decreased curvature and plaque size (P < 0.5). Overall subjective sexual performance was reportedly improved. Increased dosage of alpha INF-2B resulted in increased severity of flu-like symptoms when compared to the lower (1 x 10(6) units) biweekly dosage. No significant difference was noted with the addition of oral Vitamin E therapy.

Adult↗

Role of the C-terminal G3 domain in sorting and secretion of aggrecan core protein and ubiquitin-mediated degradation of accumulated mutant precursors.

Aggrecan is a complex multidomain macromolecule that undergoes extensive processing and post-translational modification. A thorough understanding of the events and signals that promote translocation of aggrecan through the secretory pathway is lacking. To investigate which features of the C-terminal G3 region are necessary for successful translocation of the core protein, a number of deletion constructs based on the chick aggrecan cDNA sequence were prepared and transiently expressed in COS-1 cells and the natural host, embryonic chick chondrocytes; stable cell lines were established as well. The present results clearly establish a precise requirement for that portion of the G3 C-lectin domain encoded by exon 15 for: (i) translocation from the endoplasmic reticulum (ER) to the Golgi, (ii) secretion from the cell, (iii) galactosylation of chondroitin sulfate (CS) chains, (iv) generation of Ca(+2)-dependent galactose binding ability. Furthermore, in the absence of this subdomain there is excess accumulation in the ER of expression products leading to a stress-related response involving the chaperones Grp78 and protein disulfide isomerase, followed by degradation via a ubiquitin-proteosome pathway. All of these events in the model system faithfully mimic the naturally occurring nanomelic mutant, which also elicits a ubiquitin-mediated degradation response due to the accumulation of the truncated core protein precursor. This study represents the first report of the mode of degradation of overexpressed or misfolded proteoglycans and suggests that, although proteoglycans follow different glycosylation pathways from other glycoproteins, they are monitored by an ER surveillance system similar to that which detects other misfolded proteins.

Aggrecans↗

A rat model of Peyronie's disease associated with a decrease in erectile activity and an increase in inducible nitric oxide synthase protein expression.

PURPOSE: Our objective was to assess erectile function in saline-injected, transforming growth factor-beta 1 (TGF-beta1)-injected, and surgical injury rats after six weeks and to determine the role of nitric oxide in this rat model of Peyronie's disease. MATERIALS AND METHODS: Fifty-four adult male CD rats were divided into three groups: 1) saline-injected (0.1 ml.) into the tunica albuginea; 2) TGF-beta1 (0.5 microgram.) injected into the tunica albuginea; and 3) surgical injury to the tunica albuginea. All groups underwent electrical stimulation of the cavernosal nerve and pharmacological stimulation with acetylcholine, an endothelium-dependent vasodilator, after six weeks. In a separate group of animals, aminoguanidine (5 mg./kg. i.v.), a specific iNOS inhibitor, was administered and cavernosal nerve stimulation was performed. Cavernosal tissue was homogenized and constitutive and inducible NOS enzyme activity were measured by L-arginine to L-citrulline conversion in the presence and absence of calcium after 2 days, 3 and 6 weeks in all three groups. Cross-sections of the rat penises were examined using Hart and trichrome stains. RESULTS: Erectile function as measured by cavernosal nerve stimulation and acetylcholine injection was significantly lower (p <0.05) in the TGF-beta1-injected and surgical-injury rats when compared to the saline-injected rats. iNOS inhibition significantly increased (p <0.05) erectile responses to cavernosal nerve stimulation in the rat. iNOS was significantly higher (p <0.05) and constitutive NOS was downregulated (p <0.05) in the corpus cavernosum of the TGF-beta1-injected and surgical-injury rats after 6 weeks. The TGF-beta1-injected and surgical-injury rats exhibited thickening of the tunica albuginea, fragmentation of the elastic fibers, and collagen thickening around the neurovascular bundle. CONCLUSIONS: We have shown that erectile function is significantly lower in the TGF-beta1-injected and surgical-injury rats after 6 weeks at a time when iNOS is upregulated and constitutive NOS is downregulated. Furthermore, iNOS inhibition causes a greater erectile response in the rat, suggesting that iNOS may alter the vascular tone in the penis. These data document a possible mechanism by which some men with Peyronie's disease suffer from erectile dysfunction.

Animals↗