Association between CYP2E1 polymorphisms and susceptibility to prostate cancer

Several genetic alterations have been associated with sporadic prostate cancer (PCa). In this study, the association between RsaI and DraI polymorphisms of CYP2E1 and PCa risk was analysed in a case-control study of 227 individuals using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Regarding DraI polymorphisms, the DD genotype is over-represented in PCa cases when compared with the control group (odds ratio (OR) 2.12; 95% confidence interval (CI) 1.11-4.05; P=0.022). Regarding the RsaI polymorphism, no significant differences were found. The results of this study indicate that DraI polymorphisms of the CYP2E1 gene may be associated with a twofold increased risk for the development of PCa.

Endothelial nitric oxide synthase gene polymorphisms and genetic susceptibility to prostate cancer

The endothelial cell-specific form of nitric oxide synthases (ecNOS) is localized at 7q35-q36 and is involved in vascular development and tumour growth in human prostate cancer. We have conducted a case-control study to investigate the prevalence of two polymorphisms at intron 4 (ecNOS4a/b) and exon 7 (Glu-Asp298) of ecNOS gene in 125 prostate cancer (PCa) patients and in 153 controls. We observed that the a-allele (aa or ab genotypes from ecNOS4a/b) was over-presented in the group of PCa with Gleason histological grade >or=7 (P=0.041). With regard to the Glu-Asp298 polymorphism, patients with the T-allele were younger than patients with no T-allele (P=0.037), and a statistically significant difference was noted in the Glu-Asp298 genotype distribution between cases with advanced disease and cases with localized disease (P=0.0013). When comparing cases and controls with logistic regression analysis we observed that the presence of the a-allele is associated with prostate cancer risk (odds ratio (OR) 1.83; 95% confidence interval (CI) 1.06-3.17; P=0.029), to high histological grade (Gleason >or=7) of PCa (OR 2.18; 95% CI 0.95-4.98; P=0.062) and with the risk of progression of the cancer disease (OR 2.85; 95% CI 1.19-6.82; P=0.018). Furthermore, we found that carriers with the combination of the a-allele (aa and ab ecNOS4a/b genotypes) and T-allele (GT and TT from Glu-Asp298) have a threefold increase in prostate cancer risk (OR 3.13; 95% CI 1.41-6.91, P=0.004). In summary, we have identified an NO-related genetic risk factor for prostate cancer that may help in understanding the molecular mechanism involved in the individual susceptibility to prostate cancer.

Hemagglutinin residues of recent human A(H3N2) influenza viruses that contribute to the inability to agglutinate chicken erythrocytes

To identify the molecular determinants contributing to the inability of recent human influenza A(H3N2) viruses to agglutinate chicken erythrocytes, phenotypic revertants were selected upon passage in eggs or MDCK cells. The Leu194Ile or Val226Ile substitutions were detected in their hemagglutinin (HA) sequence concomitantly with the phenotypic reversion. Remarkably, as little as 3.5% of variants bearing a Val226Ile substitution was found to confer the ability to agglutinate chicken erythrocytes to the virus population. Hemadsorption assays following transient expression of mutated HA proteins showed that the successive Gln226 --> Leu --> Ile --> Val changes observed on natural isolates resulted in a progressive loss of the ability of the HA to bind chicken erythrocytes. The Val226Ile change maintained the preference of the HA for SAalpha2,6Gal over SAalpha2,3Gal and enhanced binding of the HA to alpha2,6Gal receptors present on chicken erythrocytes. In contrast, simultaneous Ser193Arg and Leu194Ile substitutions that were found to confer the ability to agglutinate sheep erythrocytes increased the affinity of the HA for SAalpha2,3Gal.

The "in vivo" and "ex vivo" roles of cylcooxygenase-2, nuclear factor-kappaB and protein kinases pathways in the up-regulation of B1 receptor-mediated contraction of the rabbit aorta

This study investigates some of the mechanisms involved in the up-regulation of the B1 receptor in the rabbit aorta. Pre-treatment of rabbit aorta with cyclooxygenase (COX) inhibitors 5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsuphonyl) phenyl-2 (5H)-furanone (DFU), N-[2-cyclohexyloxy-4-nitrophenyl] methanesulfonamide (NS-398) or with indomethacin, but not with piroxicam, for 6 h, resulted in a significant inhibition of time-dependent contraction to the B1 selective agonist des-Arg9-Bradykinin (des-Arg9-BK), without affecting noradrenaline (NA) response. The kinase inhibitors bisindoylmaleimidine IX (RO 318220), staurosporine, genistein or tyrphostin B42 and the nuclear factor-kappaB (NF-kappaB) inhibitors pyrrolidinedithiocarbamate (PDTC), N(alpha)-p-tosyl-L-lysine chloro-methyl ketone (TLCK) or sulfasalazine, incubated for 6 h each, resulted in similar inhibition of des-Arg9-BK-induced contraction. When these inhibitors were pre-incubated for only 30 min, 6 h after setting up the preparations, sulfasalazine was the only drug tested that inhibited des-Arg9-BK-induced contraction, an effect which was reverted after the washing-out of the preparations. In preparations obtained from animals treated with lipopolysaccharide i.v. (LPS) 12 h prior, the up-regulation of B1 receptor in the aorta was markedly increased. The treatment of rabbits with PDTC, dexamethasone (Dexa), genistein or an association of subliminal doses of Dexa or with PDTC 12 h prior, which alone had no effect, all caused significant inhibition of des-Arg9-BK-induced contraction in the rabbit aorta. These results indicate that the time-dependent up-regulation of des-Arg9-BK-mediated contraction in the rabbit aorta involves the activation of protein kinase C, tyrosine kinase, through participation of COX-2 and the NF-kappaB transcription factor pathways.

Neuroethologic differences in sleep deprivation induced by the single- and multiple-platform methods

It has been proposed that the multiple-platform method (MP) for desynchronized sleep (DS) deprivation eliminates the stress induced by social isolation and by the restriction of locomotion in the single-platform (SP) method. MP, however, induces a higher increase in plasma corticosterone and ACTH levels than SP. Since deprivation is of heuristic value to identify the functional role of this state of sleep, the objective of the present study was to determine the behavioral differences exhibited by rats during sleep deprivation induced by these two methods. All behavioral patterns exhibited by a group of 7 albino male Wistar rats submitted to 4 days of sleep deprivation by the MP method (15 platforms, spaced 150 mm apart) and by 7 other rats submitted to sleep deprivation by the SP method were recorded in order to elaborate an ethogram. The behavioral patterns were quantitated in 10 replications by naive observers using other groups of 7 rats each submitted to the same deprivation schedule. Each quantification session lasted 35 min and the behavioral patterns presented by each rat over a period of 5 min were counted. The results obtained were: a) rats submitted to the MP method changed platforms at a mean rate of 2.62 +/- 1.17 platforms h-1 animal-1; b) the number of episodes of noninteractive waking patterns for the MP animals was significantly higher than that for SP animals (1077 vs 768); c) additional episodes of waking patterns (26.9 +/- 18.9 episodes/session) were promoted by social interaction in MP animals; d) the cumulative number of sleep episodes observed in the MP test (311) was significantly lower (chi-square test, 1 d.f., P < 0.05) than that observed in the SP test (534); e) rats submitted to the MP test did not show the well-known increase in ambulatory activity observed after the end of the SP test; f) comparison of 6 MP and 6 SP rats showed a significantly shorter latency to the onset of DS in MP rats (7.8 +/- 4.3 and 29.0 +/- 25.0 min, respectively; Student t-test, P < 0.05). We conclude that the social interaction occurring in the MP test generates additional stress since it increases the time of forced wakefulness and reduces the time of rest promoted by synchronized sleep.

[Cryopreservation of bone marrow and peripheral blood stem cells using a controlled rate freezing system: experience with 86 procedures]

The cryopreservation of hematopoietic stem cells can be used for rescuing the hematopoiesis after high dose chemotherapy.

PURPOSE

The ice crystal formation during the freezing procedure is the key point that can be harmful to the cells. The cryopreservation of hematopoietic stem cells in a controlled-rate freezer could decrease the cell damage.

METHODS

Twenty-three patients with a median age of 26 years (range 03-57) had bone marrow and/or peripheral blood stem cells harvested from March 1993 through October 1994, ending up to 86 freezing procedures. The patient's diagnoses are as follows: Non-Hodgkin's Lymphoma (n = 5); Acute Myelogenous Leukemia (n = 8); Acute Lymphocytic Leukemia (n = 6); Hodgkin's disease (n = 3); Multiple Myeloma (n = 1). The cells were frozen away in a controlled-rate freezer chamber at the following rate: -1 degree C/min from room temperature to -45 degrees C and then, at -10 degrees C/min down to -80 degrees C. After freezing, the cells were kept into mechanical freezers until the marrow infusion. To mobilize PBSC (peripheral blood stem cells), G-CSF (granulocyte colony stimulating factor) was given.

RESULTS

A median of 3.16 x 10(8) cells/kg (range 0.86-24.22) of PBSC and 2.03 x 10(8) cells/kg (0.19-12.21) of bone marrow cells were frozen. The median time to reach granulocytes greater than 500/microL and platelets greater than 20,000/microL was 12 days (range 8-40) and 31 days (range 8-80), respectively. All patients had marrow engraftment after infusion of hematopoietic stem cells.

CONCLUSION

The cryopreservation procedure using a controlled-rate freezer can store hematopoietic stem cells and potentially, cause less damage to the cells.

Unrelated peripheral blood stem cell transplantation for Fanconi anemia

The Brazilian unrelated bone marrow donor program began in 1993 and an unrelated matched donor was found for a Fanconi anemia patient without a sibling match. An 11-year-old female recipient received FTBI (6.0 Gy) and cyclophosphamide (40 mg/kg) as conditioning. The 41-year-old female unrelated donor received G-CSF at 5 micrograms/kg x 5 days, and on day 6 and 7 postmobilization, peripheral blood stem cells were harvested. Engraftment was seen on day 19 post-BMT and she remains alive and well on day 191+. This case supports the potential role of harvesting G-CSF-stimulated PBSC for unrelated bone marrow transplantation.

[Pulmonary arteriovenous fistula. A case report and review of the literature]

The aim of this paper is to review clinical and laboratory features of this unusual pathology and its complications, indicating transcatheter embolization as a first choice for its management. Our case report is of a seven year-old child, with complex pulmonary arteriovenous fistula of the anterior segment of right superior lobe, which was diagnosed mainly by cintilography and pulmonary angiogram. Clinically she had cyanosis, fatigue with exertion, clubbing of the fingers and polycythemia with low partial pressure of oxygen (PAO2: 68.1 mmHg; Sat O2: 92.4%; Hct: 47.5%; Hb: 16 gr%). She did not have Rendu-Osler-Weber disease. The anatomic structure and localization of the complex fistula was showed by cineangiographic study. We preferred to manage this fistula with transcatheter embolization with a 02 gauge stainless steel coil occluding device (Gianturco-Wallace), as it was single and the patient was too young for sustain surgical trauma and the outcome would be positively satisfactory. After the embolization cyanosis was relieved and we could see normal pulmonary circulation following the point of the pre-existing fistula. We concluded that a judicious assessment by cineangiography could help select the transcatheter embolization procedure as an attractive therapeutic approach instead of surgery.