233 research outputs found
Review: mitochondrial defects in breast cancer
Mitochondria play important roles in cellular energy metabolism, free radical
generation, and apoptosis. Mitochondrial DNA has been proposed to be involved in
carcinogenesis because of its high susceptibility to mutations and limited repair
mechanisms in comparison to nuclear DNA. Breast cancer is the most frequent
cancer type among women in the world and, although exhaustive research has been
done on nuclear DNA changes, several studies describe a variety of mitochondrial
DNA alterations present in breast cancer. In this review article, we to provide a
summary of the mitochondrial genomic alterations reported in breast cancer and
their functional consequences
Far Infrared Slab Lensing and Subwavelength Imaging in Crystal Quartz
We examine the possibility of using negative refraction stemming from the
phonon response in an anisotropic crystal to create a simple slab lens with
plane parallel sides, and show that imaging from such a lens should be possible
at room temperature despite the effects of absorption that are inevitably
present due to phonon damping. In particular, we consider the case of crystal
quartz, a system for which experimental measurements consistent with all-angle
negative refraction have already been demonstrated. Furthermore, we investigate
the possibility of subwavelength imaging from such materials, and show that it
should be possible for certain configurations.Comment: 12 pages, 10 figure
Congenital Destructive Hemispheric Lesions And Epilepsy: Clinical Features And Relevance Of Associated Hippocampal Atrophy.
We studied the clinical, EEG and MRI findings in 19 patients with epilepsy secondary to congenital destructive hemispheric insults. Patients were divided in two groups: 10 with cystic lesions (group 1), and 9 with atrophic lesions (group 2). Seizure and EEG features, as well as developmental sequelae were similar between the two groups, except for the finding that patients of group 2 more commonly presented seizures with more than one semiological type. MRI showed hyperintense T2 signal extending beyond the lesion in almost all patients of both groups, and it was more diffuse in group 2. Associated hippocampal atrophy (HA) was observed in 70% of group 1 patients and 77.7% of group 2, and it was not correlated with duration of epilepsy or seizure frequency. There was a good concordance between HA and electroclinical localization. The high prevalence of associated HA in both groups suggests a common pathogenesis with the more obvious lesion. Our findings indicate that in some of these patients with extensive destructive lesions, there may be a more circumscribed epileptogenic area, particularly in those with cystic lesions and HA, leading to a potential rationale for effective surgical treatment.58990-100
De Novo Psychogenic Seizures After Epilepsy Surgery: Case Report.
The occurrence of de novo psychogenic seizures after epilepsy surgery is rare, and is estimated in 1.8% to 3.6%. Seizures after epilepsy surgery should be carefully evaluated, and de novo psychogenic seizures should be considered especially when there is a change in the ictal semiology. We report a patient with de novo psychogenic seizures after anterior temporal lobe removal for refractory temporal lobe epilepsy. Once psychogenic seizures were diagnosed and psychiatric treatment was started, seizures stopped.58535-
A gene signature of 8 genes could identify the risk of recurrence and progression in Dukes' B colon cancer patients
The benefit of postoperative adjuvant chemotherapy in patients with Dukes' B colorectal cancer is still uncertain and its routine use is not recommended. The five-year relapse rate is approximately 25-40% and the identification of patients at high risk of recurrence would represent an important strategy for the use of adjuvant chemotherapy. We retrospectively analyzed gene expression profiles in frozen tumor specimens from patients with Dukes' B colorectal cancer by using high density oligonucleotide microarrays. Our results show a subset of 48 genes differentially expressed with an associated probability <0.001 in the t-test. Another statistical procedure based on the Fisher criterion resulted in 11 genes able to separate both groups. We selected the 8 genes present in both subsets. The differential expression of five genes (CHD2, RPS5, ZNF148, BRI3 and MGC23401) in colon cancer progression was confirmed by real-time PCR in an independent set of patients of Dukes' B and C stages
Conformational polymorphism of the antidiabetic drug chlorpropamide
In this paper, the main features of Raman spectroscopy, one of the first choice methods in the study of polymorphism in pharmaceuticals, are presented taking chlorpropamide as a case of study. The antidiabetic drug chlorpropamide (1-[4- chlorobenzenesulphonyl]-3-propyl urea),which belongs to the sulfonylurea class, is known to exhibit, at least, six polymorphic phases. These forms are characterized not onlyby variations in their molecular packingbut also intheir molecular conformation. In this study, the polymorphism of chlorpropamide is discussed on the basis of Raman scattering measurements and quantum mechanical calculations. The main spectroscopic features that fingerprint the crystalline forms are correlated with the corresponding crystalline structures. Using a theoretical approach on the energy dependence of the conformers, simulated molecular torsion angles are plotted versus the formation energy,which provides a satisfactory agreement between the torsion angles at the energy minima and the experimental values observed in the different solid forms of chlorpropamide angles at the energy minima and the experimental values observed in the different solid forms of chlorpropamide angles at the energy minima and the experimental values observed in the different solid forms of chlorpropamide versus the formation energy,which provides a satisfactory agreement between the torsion angles at the energy minima and the experimental values observed in the different solid forms of chlorpropamide.Fil: Ayala, A. P.. Universidade de Sao Paulo; Brasil. Universidade Estadual do Ceará; BrasilFil: Caetano, M. W. C.. Universidade Estadual do Ceará; BrasilFil: Honorato, S. B.. Universidade Estadual do Ceará; BrasilFil: Mendes Filho, J.. Universidade Estadual do Ceará; BrasilFil: Siesler, H. W.. Universitat Essen; AlemaniaFil: Faudone, Sonia Nerina. Universidade Federal de Santa Catarina; BrasilFil: Cuffini, Silvia Lucia. Universidade Federal de Santa Catarina; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Martins, F. T.. Universidade de Sao Paulo; BrasilFil: Da Silva, C. C. P.. Universidade de Sao Paulo; BrasilFil: Ellena, J.. Universidade de Sao Paulo; Brasi
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