Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung

Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.      

TREATMENT OF PALMOPLANTER HYPERHIDROSIS BY IONTOPHORESIS

Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis     

Aortic dissection with intimal intussusception: diagnosis and management

A man presented with acute chest and back pain with loss of consciousness. CT scan showed a mass in the arch that extended into the descending aorta. A diagnosis of type I aortic dissection was ultimately made by echocardiography. At surgery there was a circumferential intimal tear in the aortic root, and an intussuscepted dissection flap was retrieved from the arch and descending aorta.     

Mortality in Western Australian psychiatric patients

  Background: The aim was to examine mortality in psychiatric patients in Western Australia (WA), over a time period of considerable change in the delivery of mental health services. Methods: A population-based record linkage analysis was undertaken to quantify mortality among people with mental illness in WA. Mortality rates were calculated in users of mental health services and compared with rates in the whole population of WA. Trends in mortality were also examined using relative survival analysis, and proportional hazards regression. Results: The overall mortality rate ratio was 2.57 in males (95% CI: 2.51–2.64), and 2.18 in females (2.12–2.24). The highest cause-specific mortality rate ratio was for deaths due to suicide [RR: 7.37 in males (95% CI: 6.74–8.05) and 8.38 in females (95% CI: 7.11–9.89)], with mortality rate ratios being significantly greater than 1 for all other major causes of death. A relative survival analysis found that the excess mortality risk was concentrated in the first few years after first contact with mental health services. Proportional hazards regression analysis found a slight elevation of mortality rates over time. Conclusions: Mortality among psychiatric patients remains high and appears to be increasing. Highest excess mortality rate is associated with suicide, but mortality rates are significantly elevated for all major causes of death. Accepted: 10 April 2000     

Body mass index in relation to ovarian cancer survival.

Evidence for an association between indicators of adiposity and survival after ovarian cancer has been inconsistent. A prospective cohort study was conducted in China to examine the relationship between ovarian cancer survival and body mass index (BMI). From the 214 patients recruited in 1999 to 2000 with histopathologically confirmed invasive epithelial ovarian cancer, 207 patients or their close relatives (96.7% of cases) were traced and followed to 2003. Deaths were recorded and Cox proportional hazards regression was used to obtain hazard ratios (HR) and 95% confidence intervals (95% CI) from multivariate models. Reduced survival was observed among patients with BMI > or = 25 kg/m(2) at 5 years before diagnosis (P = 0.001). There were 98 (59.8%) of 164 patients with BMI <25 kg/m(2) survived to the time of interview compared with only 15 women (34.9%) among the 43 patients whose BMI was > or =25 kg/m(2). The HRs significantly increased with higher BMI at 5 years before diagnosis but not at diagnosis nor at age 21 years. The adjusted HR was 2.33 (95% CI, 1.12-4.87) for BMI of > or =25 versus <20 kg/m(2), with a significant dose-response relationship. The HR was 3.31 (95% CI, 1.26-8.73) among patients who had been overweight or obese at age 21 years, but a linear dose-response was not found. We conclude that premorbid BMI may have independent prognostic significance in ovarian cancer.     

Percutaneous nephropexy

OBJECTIVE: The authors present a 12-year (1986-98) study of a new procedure called percutaneous nephropexy (PCNP). This procedure was performed on 51 renal ptosis patients at two urological departments (in Pakistan and Hungary) with satisfactory results. The idea for PCNP was adapted from the observation that after drain insertion following nephrostomy a scar is quite sufficient to hold the kidney in place. That idea was used to fix the kidney at the required level. MATERIAL AND METHODS: Thirteen patients complained of a palpable mobile mass in the abdomen while others suffered from pain in their affected flank with recurrent attacks of urinary tract infection. On ultrasonic examination the kidney was found to be lower than the normal position. This observation was confirmed by a standing intravenous urography (IVU) examination that also showed a tortuous ureter. Nine patients also had a stone in the affected kidney. The operation involved puncture and dilatation of a channel through the lower calyx. RESULTS: Control IVU examination was performed after wound healing and was repeated 2 months after the operation, followed by consecutive ultrasonic examinations. Standing X-ray films obtained after contrast material injection showed the kidney to be at a higher level with a straight ureter. Forty-five patients (88.2%) recovered completely. CONCLUSION: In the authors' opinion PCNP is a good alternative to open nephropexy operations in renal ptosis cases, particularly when laparoscopic surgery facilities are not available. Although PCNP was developed in circumstances in which the availability of equipment was restricted, in terms of benefits it is comparable with laparoscopic nephropexy.     

Atypical respiratory complications of dengue fever

In last decade, dengue has emerged as one of the most important vector born disease. With increasing cases, uncommon presentations and complications are now commonly recognized. Here, we report two cases of rare pattern of respiratory involvement in dengue: acute respiratory distress syndrome and bronchiolitis with respiratory failure.