ABSTRACT
A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering ^{66}Ni as the lightest nuclear system with shape isomerism. By employing the two-neutron transfer reaction induced by an ^{18}O beam on a ^{64}Ni target, at the sub-Coulomb barrier energy of 39 MeV, all three lowest-excited 0^{+} states in ^{66}Ni were populated and their γ decay was observed by γ-coincidence technique. The 0^{+} states lifetimes were assessed with the plunger method, yielding for the 0_{2}^{+}, 0_{3}^{+}, and 0_{4}^{+} decay to the 2_{1}^{+} state the B(E2) values of 4.3, 0.1, and 0.2 Weisskopf units (W.u.), respectively. MCSM calculations correctly predict the existence of all three excited 0^{+} states, pointing to the oblate, spherical, and prolate nature of the consecutive excitations. In addition, they account for the hindrance of the E2 decay from the prolate 0_{4}^{+} to the spherical 2_{1}^{+} state, although overestimating its value. This result makes ^{66}Ni a unique nuclear system, apart from ^{236,238}U, in which a retarded γ transition from a 0^{+} deformed state to a spherical configuration is observed, resembling a shape-isomerlike behavior.
ABSTRACT
INTRODUCTION: breast cancer has the highest incidence in women.Glutathione S-transferases (GSTs) are a large group of enzymes involved in the metabolism of xenobiotics. The members of this gene superfamily are involved in the development of multiple cancers. OBJECTIVES: the aim of the study was to see whether the GSTM1, GSTT1 and GSTP1 genetic polymorphisms are risk factors for patients diagnosed with multiple malignancies, of which at least one is located in the breast. MATERIALS AND METHODS: in the period between 2005 and 2012,of the 520 patients diagnosed with breast cancer, 69 had multiple primitive malignant tumors, of which at least one was localized in the breast. The research on GSTM1, GSTT1 and GSTP1 genotypes consisted of 59 patients diagnosed with multiple breast cancers or with breast cancer in association with another type of cancer, compared with a group of healthy controls. RESULTS: in the subgroup of patients with breast cancer in association with another type of cancer, the GSTM1 null genotype was present in 61.2% of patients, compared to 29% of controls; the subgroup of metachronous breast cancers, the presence of any of the GSTT1 or GSTM1 null genotypes was statistically significantly different from that of controls (65.2%vs. 28.5%); in the subgroup with synchronous cancers, the GSTM1 null genotype was found in 66.6% of patients compared to 9% for the controls, and the presence of any null genotype (GSTM1 and GSTT1) was also statistically significant in the case group. CONCLUSIONS: the GSTM1 null genotype is a risk factor for synchronous breast cancers and for breast cancer associated with extramammary cancer; the presence of null genotypes(GSTM1 or GSTT1) is a risk factor for multiple breast cancer(bilateral or synchronous); the GSTT1 null genotype and the heterozygous variant allele (Ile105Val) and homozygous variant allele (Val105Val) of GSTP1 are not risk factors for the cases studied.
Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/genetics , Glutathione S-Transferase pi/genetics , Glutathione Transferase/genetics , Neoplasms, Multiple Primary/genetics , Neoplasms, Second Primary/genetics , Polymorphism, Single Nucleotide , Alleles , Breast Neoplasms/diagnosis , Case-Control Studies , Female , Genotype , Humans , Isoleucine , Neoplasms, Multiple Primary/diagnosis , Neoplasms, Second Primary/diagnosis , Predictive Value of Tests , Risk Factors , Sensitivity and Specificity , ValineABSTRACT
A new method for investigation of the swelling of polymers on exposure to gas or vapour has been devised and tested. It uses an optical profilometer (based on the chromatic aberration of a lens system) which is integrated into a computer-controlled gas-dosing and mixing setup. Gas and/or vapour concentration-dependent measurements have been carried out for thick layers of the polymers commonly used in gravimetric and capacitive gas sensors: poly(acrylic acid) (PAA), poly(vinyl pyrrolidone) (PVP), poly(ether urethane) (PEUT), and polydimethylsiloxane (PDMS). The thickness of PAA, PVP, and PEUT films changed significantly on exposure to humidity. These data have been used to derive the sorption isotherms of the respective polymers, which were found to be Henry or Flory-Huggins isotherms. Comparison of the geometrical (swelling) responses with capacitive responses revealed a strong correlation. The correlation, which occurs because both types of response are proportional to the water content of the polymer, is also valid for polymers with nonlinear gas responses. Finally the geometrical and electrical characteristics of the capacitive samples were used to explain the dependence of the capacitive response of different polymers on the concentration of the target gas or vapour. In this way was deduced that PDMS, which does not swell on exposure to humidity, swells in the presence of 2,3-dimethylpentane, for which no profilometer evaluations are yet available.
ABSTRACT
Worldwide, cardiovascular events represent the major cause of morbidity and mortality. A key role in the pathogenesis of these events is played by platelets. Interventional procedures, with placement of coronary and vascular stents, often represent the preferred therapeutic strategy. Antiplatelet medications are considered first-line therapy in preventing cardiovascular thrombotic events. A wide array of antiplatelet agents is available, each with different pharmacological properties. When patients on antiplatelet agents present for surgery, the perioperative team must design an optimal strategy to manage antiplatelet medications. Each patient is stratified according to risk of developing a cardiovascular thrombotic event and inherent risk of surgical bleeding. After risk stratification analysis, various therapeutic pathways include continuing or discontinuing all antiplatelet agents or maintaining one antiplatelet agent and discontinuing the other. This review focuses on the pharmacological and pharmacokinetic properties of both older and novel antiplatelet drugs, and reviews current literature and guidelines addressing options for perioperative antiplatelet management.
Subject(s)
Perioperative Care , Platelet Aggregation Inhibitors/therapeutic use , Aspirin/adverse effects , Aspirin/therapeutic use , Blood Coagulation , Coronary Artery Disease/prevention & control , Humans , Platelet Activation , Platelet Aggregation Inhibitors/adverse effects , Purinergic P2Y Receptor Antagonists/therapeutic use , Stroke/prevention & controlABSTRACT
BACKGROUND: Mesna is a sulfohydrate administered as a supportive drug in conjunction with oxazaphosphorines to prevent bladder toxicity from metabolites. When oxazaphosphorines are given simultaneously with platinum drugs, Mesna binds with platinum drugs as well. Previously we showed in cell culture, that Mesna reduces the efficacy of some platinum drugs. Here we elucidate the chemical reaction mechanism. MATERIAL AND METHODS: Cisplatin, Carboplatin and a novel platinum agent Oxiplatin were incubated with Mesna and the rate of disappearance of Mesna was measured, using an oxidation/reduction reaction between MTT and Mesna. RESULTS: All three platinum agents reacted with Mesna, but the chemical details differed largely. The molar ratios were 3:1, 2:1, and 1:1 for the reactions of Mesna with Oxiplatin, Cisplatin, and Carboplatin, respectively. The speed of the reaction followed a similar pattern, being fastest for Oxiplatin and slowest for Carboplatin. CONCLUSION: When considering the pharmacokinetics of Mesna and these platinum compounds and their reactivity, it appears unlikely that the reaction of Mesna with Carboplatin will become clinically relevant, while Cisplatin, might react with Mesna in patient serum.
Subject(s)
Antineoplastic Agents/chemistry , Carboplatin/chemistry , Cisplatin/chemistry , Mesna/chemistry , Organoplatinum Compounds/chemistry , Platinum Compounds/chemistry , Pyridines/chemistry , Calibration , Kinetics , Molecular StructureABSTRACT
The potential of medical therapy to influence the courses and outcomes of patients with thoracic aortic aneurysms is not known. The aim of this study was to determine whether statin intake is associated with improved long-term outcomes in these patients. A total of 649 patients with thoracic aortic aneurysms were studied, of whom 147 were taking statins at their first presentation and 502 were not. After a median follow-up period of 3.6 years, 30 patients (20%) taking statins had died, compared with 167 patients (33%) not taking statins (hazard ratio 0.68, 95% confidence interval 0.46 to 1, p = 0.049); 87 patients (59%) taking statins reached the composite end point of death, rupture, dissection, or repair compared with 378 patients (75%) not taking statins (hazard ratio 0.72, 95% confidence interval 0.57 to 0.91, p = 0.006). After adjustments for co-morbidities, the association between statin therapy and the composite end point was driven mainly by a reduction in aneurysm repairs (hazard ratio 0.57 95% confidence interval 0.4 to 0.83, p = 0.003). On Kaplan-Meier analysis, the survival rate of patients taking statins was significantly better (p = 0.047). In conclusion, the intake of stains was associated with an improvement in long-term outcomes in this cohort of patients with thoracic aortic aneurysms. This was driven mainly by a reduction in aneurysm repairs.
Subject(s)
Aortic Aneurysm, Thoracic/drug therapy , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Aged , Aged, 80 and over , Aortic Aneurysm, Thoracic/mortality , Cohort Studies , Confidence Intervals , Connecticut/epidemiology , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Odds Ratio , Risk Factors , Survival Rate , Time Factors , Treatment OutcomeABSTRACT
There are reported the results of certain measurements made on 158 human cadavers of both sexes. A series of main parameters are given, such as the distance between the superior mesenteric vein and on the one hand its confluence with other vessels and on the other hand the pancreas and the horizontal part of the duodenum: the distance between the superior mesenteric vein together with the portal vein, and the inferior caval vein; the diameters of the portal trunk and the confluence angle between the roots of the portal vein. The results reflect the possibility to perform a troncular portocaval anastomosis in at least 90 per cent of the cases. The authors' attention was, however, directed towards the anatomy of the superior mesenteric vein, as this vessel is preferred by some surgeons in the achievement of the portocaval anastomosis.