IG20, in contrast to DENN-SV, (MADD splice variants) suppresses tumor cell survival, and enhances their susceptibility to apoptosis and cancer drugs

We identified seven putative splice variants of the human IG20 gene. Four variants namely, IG20, MADD, IG20-SV2 and DENN-SV are expressed in human tissues. While DENN-SV is constitutively expressed in all tissues, expression of IG20 appears to be regulated. Interestingly, overexpression of DENN-SV enhanced cell replication and resistance to treatments with TNFalpha, vinblastine, etoposide and gamma-radiation. In contrast, IG20 expression suppressed cell replication and increased susceptibility to the above treatments. Moreover, cells that were resistant and susceptible to TNFalpha-induced apoptosis exclusively expressed endogenous DENN-SV and IG20, respectively. When PA-1 ovarian cancer cells that are devoid of endogenous IG20 variant, but express higher levels of DENN-SV, were transfected with IG20, they showed reduced cell proliferation and increased susceptibility to apoptosis induced by TNFalpha, TRAIL and gamma-radiation. This indicated that overexpression of IG20 can override endogenous DENN-SV function. CrmA reversed the effects of IG20, but not DENN-SV. In contrast, dominant-negative-I-kappa B reversed the effects of DENN-SV, but not IG20, and showed that DENN-SV most likely exerted its effects through NFkappaB activation. Together, our data show that IG20 gene can play a novel and significant role in regulating cell proliferation, survival and death through alternative mRNA splicing.     

Outpatient treatment of spontaneous pneumothorax using an improved pocket sized Heimlich valve

We report two patients, who have used Pneumostat to replace the conventional underwater seal drainage system for recurrent pneumothorax. Both patients had required repeated chest tube insertion for recurrent pneumothorax and needed a longer hospital stay. Both patients were able to be discharged with the Pneumostat device and were reviewed in outpatient clinic. Both patients had optimal clinical improvement and chest X-ray showed no residual pneumothorax.     

Serial C-reactive Protein Measurements in Infective Complications Following Cardiac Operation: Evaluation and Use in Monitoring Response to Therapy

Serum C-reactive protein (CRP) was studied serially in 100 patients who underwent cardiac operation and in another 17 patients in whom serious infections including prosthetic valve endocarditis developed in the early postoperative period. Eleven patients with late onset of prosthetic valve endocarditis and infective endocarditis were also investigated. The assay method used was radial immunodiffusion. Patients without postoperative infective complications showed a rapid increase in CRP levels, which reached a peak within 72 hours after operation followed by a progressive decline. The differences between the CRP levels in infected and uninfected patients were significant (p < 0.01). Serial measurements were of prognostic value in evaluating the response to chemotherapy and in predicting the outcome of the disease.