Impaired helix 12 dynamics due to proline 892 substitutions in the androgen receptor are associated with complete androgen insensitivity

Human Molecular Genetics (2006) 15, 921–931;     

Enantioselective metabolism and cytotoxicity of R-ifosfamide and S-ifosfamide by tumor cell-expressed cytochromes P450.

The anticancer prodrug ifosfamide (IFA) contains a chiral phosphorous atom and is administered in the clinic as a racemic mixture of R-IFA and S-IFA. Hepatic cytochrome P450 (P450) enzymes exhibit enantioselective preferences in the metabolism of R-IFA and S-IFA; however, the impact of this selectivity on P450-dependent anticancer activity is not known. Presently, the metabolism and cytotoxicity of R-IFA and S-IFA were determined in 9L gliosarcoma and Chinese hamster ovary tumor cells expressing an IFA-activating P450 enzyme and by in vitro steady-state kinetic analysis using cDNA-expressed P450 enzymes. Tumor cells expressing P450 enzyme CYP3A4 were the most sensitive to R-IFA cytotoxicity, whereas tumor cells expressing CYP2B1 or CYP2B6 were most sensitive to cyclophosphamide (CPA), an isomer of IFA. Correspondingly, CYP3A4-expressing cells and cDNA-expressed CYP3A4 metabolized R-IFA to yield the active, 4-hydroxylated metabolite at a 2- to 3-fold higher rate than they metabolized S-IFA or CPA. CYP2B cells and cDNA-expressed CYP2B enzymes metabolized CPA almost exclusively by 4-hydroxylation, whereas R-IFA and S-IFA were substantially converted to inactive, N-dechloroethylated metabolites. Further investigation revealed that CYP3A1, a rat enzyme, exhibited superior kinetic properties compared with the human enzyme CYP3A4, with R-IFA and S-IFA both metabolized with high catalytic efficiency by 4-hydroxylation and with a K(m) value of 200 microM, approximately 5-fold lower than CYP3A4. Based on these kinetic parameters and metabolic profiles, R-IFA is expected to exert greater anticancer activity than S-IFA or CPA against tumors that express CYP3A enzymes, whereas tumors expressing CYP2B enzymes may be more sensitive to CPA treatment.     

Xanthogranulomatous orchitis: Review of the published work and report of one case

Xanthogranulomatous orchitis is an extremely rare inflammatory non-neoplastic destructive lesion of the testis. We report a 44-year-old man who presented with right scrotal swelling and two discharging sinuses. Testicular tumor markers were normal. Scrotal ultrasound showed heterogeneous testicular areas and irregular margin of the tunica. Surgical exploration revealed infected, unhealthy testicular tissue with necrosis and tumor-like lesion. Orchidectomy was done and histopathology showed xanthogranulomatous orchitis.     

Cetirizine dihydrochloride interaction with some diclofenac complexes.

IR, 1H NMR and mass spectrometric studies showed that cetirizine dihydrochloride interacted strongly with diclofenac sodium, even when the latter was metal bound, forming high molecular weight stable adducts. These new formations were unaffected by the possible steric constraints that may exist because of coordination yet did not have the power to break the formed coordinate bonds. The formed ionic bond took place between the carbonyl ion of diclofenac and the positively charged piperazine ring of cetirizine, forming a ternary compound in the case of the divalent metal clusters (Ca{(dic)2.2H2O}, Mg{(dic)2.2H2O}, Zn{(dic)2.2H2O}) and a quaternary one with the trivalent iron cluster (Fe{dic}3.3H2O). IR bands assigned to nuNH, deltaNH and nuC-N were shifted to lower frequency values in the spectra of the complexes; thus showing that coordination took place at the NH of the diphenylamine. TG and elemental analysis confirmed these results.     

Magnum system for routine coronary angioplasty: A randomized study

The Magnum system, initially designed for coronary angioplasty (PTCA) of chronic total occlusion, consists of a balloon catheter and a solid steel 0.021 inch (0.53 mm) steerable and removable wire with a soft and moldable distal portion, tipped with a 1 mm olive. To evaluate its performance in routine PTCA, 200 unselected consecutive patients were randomized to two equal groups, i.e., group Magnum (100 patients, 115 vessels) and group Standard (100 patients, 118 vessels) including 18 and 21 patients with chronic total occlusions, respectively. Randomization was performed by the sealed envelope system in the catheterization laboratory and crossover of system was imposed if it was not possible to place a balloon correctly within 20 min of fluoroscopy time. There were no significant differences between groups concerning clinical and angiographic baseline characteristics, size of initial balloons (3.0±0.3 mm in both groups), fluoroscopy time to cross the lesion with the wire (Magnum: 4±5, Standard: 5±6 min), total fluoroscopy time (Magnum: 11 ± 9, Standard: 12±12 min), and need for crossover (Magnum: 10%, Standard: 16%). Success rates per lesion were comparable with 90% in group Magnum and 84% in group Standard, as were the complications with one inhospital death in group Standard, occurring three weeks after PTCA and stent implantation. There was no emergency operation. Six patients per group had myocardial infarction of whom two in group Magnum and one in group Standard developed a Q-wave. The following variables were significantly in favor of the Magnum system compared with the Standard system: success rate in nontotal lesions (97% versus 90%) crossover success in total occlusions (0 vs. 33%), fluoroscopy time to cross the lesion with the balloon once the wire was in place (1 ± 2 vs. 2 ± 4 min), and use of a single versus 1.2±0.5 wires per lesion. The only advantage of the Standard systems was the more common use of 7 French guiding catheters (Magnum: 40%, Standard: 53%, p = 0.09). The Magnum system compares favorably with standard systems for routine PTCA. The robust design of the Magnum wire does not impair ease of placement and safety but saves material and facilitates balloon advancement across the lesion.     

Candida albicans osteomyelitis of the spine: progressive clinical and radiological features and surgical management in three cases

Candida albicans vertebral osteomyelitis is rare. Three cases are presented. Without antifungal treatment, they developed spinal collapse and neurological deterioration within 3–6 months from the onset of symptoms. There was a delay of 4.5 and 7.5 months between the onset of symptoms and surgery. All patients were managed with surgical debridement and reconstruction and 12-week fluconazole treatment. The neurological deficits resolved completely. The infection has not recurred clinically or radiologically at 5–6 years follow-up. Although rare, Candida should be suspected as a causative pathogen in cases of spinal osteomyelitis. Without treatment the disease is progressive. As soon as osteomyelitis is suspected, investigations with MRI and percutaneous biopsy should be performed followed by medical therapy. This may prevent the need for surgery. However, if vertebral collapse and spinal cord compression occurs, surgical debridement, fusion and stabilisation combined with antifungal medications can successfully eradicate the infection and resolve the neurological deficits.     

Feasibility of cranio-spinal axis radiation with the Hi-Art tomotherapy system.

BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT.     

Fatal Dieulafoy's type ulcer in a case of gastric AL-amyloidosis

Dieulafoy's ulcer is a particular form of gastric ulcer confined to a persistent caliber artery and may lead to severe hemorrhage. We report a case of fatal gastric bleeding in a woman with benign biclonal gammapathy. Autopsy found a typical Dieulafoy's ulcer centered by a persistent caliber artery which wall was thickened by AL-amyloid deposits. Amyloidosis involved the gastric wall, but also middle caliber arteries of the liver, the lung, the pancreas, the kidney and the myocardium. AL-amyloidosis is a rare and late complication of monoclonal gammapathy and may be asymptomatic. Pathogenesis of Dieulafoy's ulcer remains unclear. In our case, local ischemia may have facilitated gastric ulceration, and amyloid deposits may have contributed to arterial rupture.