Drinking in adolescents--qualitative analysis

The aim of this paper was to explore alcohol consumption and the development of this habit in the adolescent population based on qualitative data from 59 anonymous essays written by high school students. We found that the most of adolescents had their first experiences with alcohol in the seventh or eighth grades. They reported that they usually drank alcohol to be happy, to relax, to be courageous in approaching the opposite sex, to fit into society, and to be popular. Factors affecting drinking are influence of peers, family and social attitude towards drinking, laws and enforcement of legislation. In further prevention programs, we must be able to demonstrate that "having a good time" does not mean drinking alcohol. Programs for the prevention of alcohol-related problems must begin by adolescence, including both sexes equally and can be achieved through a coordinated and intense public health effort.     

Behavioural determinants of agonistic success in invasive crayfish

Ecosystems today increasingly suffer invasions by multiple invasive species, some of which may share similar advantageous life history traits and ecological niche. In such cases, direct competition can influence invasion success of both species, and provide insights into competition without co-evolution in species equally novel to the environment. We used two widespread crayfish invaders of freshwater ecosystems of Europe, signal crayfish (Pacifastacus leniusculus) and spiny cheek crayfish (Orconectes limosus), to investigate how behavioural decisions in agonistic encounters contribute to competitive advantages in the absence of adaptation to either opponents or an environment. In direct competition against novel but comparable opponents, the key factor for establishing clear dominance of P. leniusculus in interspecific bouts was its greater tendency towards continued engagement in high-intensity fights. With O. limosus individuals consistently retreating from staged bouts as fights became more intense, P. leniusculus individuals did not need to adapt their strategy to be successful, suggesting that their agonistic behaviour intrinsically predisposed them to win. While both species are detrimental to invaded ecosystems, our results indicate that aggressive behaviour of P. leniusculus against unfamiliar opponents could allow it to more easily outcompete other comparable species and consequently present a potentially greater threat for native ecosystems.     

Giant choroid plexus cyst as an accidental finding in an older man

Choroid plexus cysts (CPC) are usually found at the end of the second trimester of pregnancy. Sometimes they can be accidentally and found on prenatal ultrasound examinations. Vast majority of CPC resolve spontaneously by 28th weeks gestation. In the older aged group the choroid plexus cysts are extremely rare pathomorphologic medical entity. Since they are almost always asymptomatic, they are therefore accidentally found on brain magnetic resonance (MR) or computed tomography (CT) scans. They are usually located in the lateral ventricles and measure around 2 cm in diameter. We present a case of a 75-year-old male with a giant choroid plexus cyst whose leading symptom was excruciating headache refractory to previous conservative therapy. He underwent surgery when osteoplastic craniotomy was performed with cyst fenestration and ablation. His recovery was uneventful with total regression of headaches. Reviewing the recent literature we did not find such a case considering the patients age and the size of the choroid plexus cyst.     

Thoracic intramedullary sarcoidosis mimicking an intramedullary tumor

Sarcoidosis is a chronic, systemic granulomatous reticulosis of unknown origin, characterized by formation of hard tubercles and noncaseatinggranulomas. Since other infectious diseases such as berylliosis, mycobacterium and fungal infections may present with a noncaseating granulomas, histological diagnosis of sarcoidosis is made using the elimination method. Central nervous system manifestations of sarcoidosis may be present in 5-10% of the cases involving cranial nerves, leptomeninges and third ventricle respectively. Any part of the central nervous system can be affected. Involvement of spinal cord in sarcoidosis is extremely rare and presents with only 0.3-0.4% in patients with systemic sarcoidosis. Intramedullary sarcoidosis is a rare first manifestation of the disease and it can mimic an intramedullary tumor, which is often manifested with symptoms that initiate from spinal cord compression, resulting in paraparesis, sensory disorders and sphincter dysfunction. We present a case of intramedullary sarcoidosis that mimics a tumor of the thoracic spinal cord. Clinical features, neuroradiological, pathohistological findings, laboratory analysis and surgical treatment of such a rare entity are being discussed.     

Regulation of β-amyloid stimulated proinflammatory responses by peroxisome proliferator-activated receptor α

Amyloid deposition within the brains of Alzheimer's Disease patients results in the activation of microglial cells and the induction of a local inflammatory response. The interaction of microglia or monocytes with β-amyloid (Aβ) fibrils elicits the activation a complex tyrosine kinase-based signal transduction cascade leading to stimulation of multiple independent signaling pathways and ultimately to changes in proinflammatory gene expression. The Aβ-stimulated expression of proinflammatory genes in myeloid lineage cells is antagonized by the action of a family of ligand-activated nuclear hormone receptors, the peroxisome proliferator-activated receptors (PPARs). We report that THP-1 monocytes express predominantly PPARγ isoform and lower levels of PPARα and PPARδ isoforms. PPAR mRNA levels are not affected by differentiation of the cells into a macrophage phenotype, nor are they altered following exposure to the classical immune stimulus, lipopolysaccharide. Previous studies have found that PPARγ agonists act broadly to inhibit inflammatory responses. The present study explored the action of the PPARα isoform and found that PPARα agonists inhibited the Aβ-stimulated expression of TNFα and IL-6 reporter genes in a dose-dependent manner. Moreover, the PPARα agonist WY14643 inhibited macrophage differentiation and COX-2 gene expression. However, the PPARα agonists failed to inhibit Aβ-stimulated elaboration of neurotoxic factors by THP-1 cells. These findings demonstrate that PPARα acts to suppress a diverse array of inflammatory responses in monocytes.     

Learning rule-based models of biological process from gene expression time profiles using gene ontology

MOTIVATION: Microarray technology enables large-scale inference of the participation of genes in biological process from similar expression profiles. Our aim is to induce classificatory models from expression data and biological knowledge that can automatically associate genes with novel hypotheses of biological process. RESULTS: We report a systematic supervised learning approach to predicting biological process from time series of gene expression data and biological knowledge. Biological knowledge is expressed using gene ontology and this knowledge is associated with discriminatory expression-based features to form minimal decision rules. The resulting rule model is first evaluated on genes coding for proteins with known biological process roles using cross validation. Then it is used to generate hypotheses for genes for which no knowledge of participation in biological process could be found. The theoretical foundation for the methodology based on rough sets is outlined in the paper, and its practical application demonstrated on a data set previously published by Cho et al. (Nat. Genet., 27, 48-54, 2001). AVAILABILITY: The Rosetta system is available at http://www.idi.ntnu.no/~aleks/rosetta. SUPPLEMENTARY INFORMATION: http://www.lcb.uu.se/~hvidsten/bioinf_cho/