Radium-226 concentration in spring water sampled in high radon regions

Water ²²⁶Ra concentration in springs was measured in regions with high indoor radon: Ural, North Caucasus (Russia), Niska Banja (Serbia), Piestany (Slovakia), and Issyk-Kul (Kyrgyzstan). This paper presents the results for ²²⁶Ra concentration above 0.03 Bq l^–1. Radium in water could indicate indoor radon problem in the region and water investigation is useful at the initial stage of radon survey. Even low ²²⁶Ra concentration in water (0.1–0.6 Bq l^–1) caused high ²²⁶Ra activity in travertine (up to 1500 Bq kg^?1), which resulted in indoor radon concentration above 2000 Bq m^?3 (Niska Banja).     

Prolonged myelination in human neocortical evolution

Nerve myelination facilitates saltatory action potential conduction and exhibits spatiotemporal variation during development associated with the acquisition of behavioral and cognitive maturity. Although human cognitive development is unique, it is not known whether the ontogenetic progression of myelination in the human neocortex is evolutionarily exceptional. In this study, we quantified myelinated axon fiber length density and the expression of myelin-related proteins throughout postnatal life in the somatosensory (areas 3b/3a/1/2), motor (area 4), frontopolar (prefrontal area 10), and visual (areas 17/18) neocortex of chimpanzees (N = 20) and humans (N = 33). Our examination revealed that neocortical myelination is developmentally protracted in humans compared with chimpanzees. In chimpanzees, the density of myelinated axons increased steadily until adult-like levels were achieved at approximately the time of sexual maturity. In contrast, humans displayed slower myelination during childhood, characterized by a delayed period of maturation that extended beyond late adolescence. This comparative research contributes evidence crucial to understanding the evolution of human cognition and behavior, which arises from the unfolding of nervous system development within the context of an enriched cultural environment. Perturbations of normal developmental processes and the decreased expression of myelin-related molecules have been related to psychiatric disorders such as schizophrenia. Thus, these species differences suggest that the human-specific shift in the timing of cortical maturation during adolescence may have implications for vulnerability to certain psychiatric disorders.     

Rotation of the Sacrum During Bellyboard Pelvic Radiotherapy

Patients with cervical, uterine, and rectal carcinomas are usually treated in the prone position using the bellyboard positioning device. Specific and uncomfortable prone position gives rise to uncertainties in the daily set-up of patients during the treatment. During investigation of translational movements, rotational movements of the pelvis are observed and investigated. The film portal imaging is used to discover patient positioning errors during treatment. We defined the rotational set-up errors by angle deviations of the sacrum. Thirty-six patients were included in the study; 15 patients were followed during the whole treatment and 21 during the first 5 consecutive treatment days. The image acquisitions were completed in 84%. Systematic and random positioning errors were analyzed in 725 images. Approximately half of the patients had adjusted to the bellyboard in the first few fractions, with sacrum angles remaining the same for the rest of the treatment. The other half had drifts of the sacrum angle during the whole treatment. The rotation of the sacrum during treatment ranged up to 14°, causing the usual set-up verification and correction procedure to result in errors up to 15 mm. Rotational movements of the patient pelvis during bellyboard pelvis radiotherapy can introduce considerable patient position error.     

Recruitment barriers in a randomized controlled trial from the physicians' perspective – A postal survey

Background  

The feasibility of randomized trials often depends on successful patient recruitment. Although numerous recruitment barriers have been identified it is unclear which of them complicate recruitment most. Also, most surveys have focused on the patients' perspective of recruitment barriers whereas the perspective of recruiting physicians has received less attention. Therefore, our aim was to conduct a postal survey among recruiting physicians of a multi-center trial to weigh barriers according to their impact on recruitment.     

Partial Left Ventriculectomy and Limited Heart Transplantation Availability

BACKGROUND AND AIM: Partial left ventriculectomy, a novel cardiac volume reduction operation, is applied in countries without a developed heart transplantation program. We sought to determine its impact in our population of patients. METHODS: Partial left ventriculectomy was performed in 38 patients during the last 4 years. Basic inclusion criteria were nonischemic dilated cardiomyopathy and poor response to medical therapy for heart failure. Hemodynamic evaluation was carried out before and after operation. A modified surgical technique of mitral valve repair and ventricle suturing was applied. RESULTS: Thirty-day, 6-month, and 2-year survival rates were 82% +/- 7%, 65% +/- 8%, and 61% +/- 9%, respectively. Duration of heart failure symptoms was the only predictor of survival (p = 0.042). A high proportion of noncardiac causes of death was noted. Functional capacity in surviving patients improved at every successive measurement up to 1 year postoperatively. CONCLUSIONS: The introduction of partial left ventriculectomy in a country with limited heart transplantation availability had a great impact on the management of end-stage heart failure and may represent the only surgical option for some patients. The average cost per patient was substantially lower when compared to heart transplantation.     

Mutant androgen receptors in prostatic tumors distinguish between amino-acid-sequence requirements for transactivation and ligand binding

Mutant androgen receptors are thought to contribute to hormone resistance in prostate carcinoma. The part they play in this process, however, is ill-defined. Here we report on transactivation by 2 mutant androgen receptors from prostatic tumors with single amino-acid exchanges in their hormone-binding domains. These exchanges enhance the transactivation property of the receptors, particularly to androsterone and androstanediol, 2 metabolized derivatives of testosterone present in the prostate. Additionally, they enhance the transactivation potential of the mutant receptors to hydroxyflutamide, an anti-androgen frequently used in hormone ablation therapy. The increased transactivation by the mutant receptors did not result from altered affinity of the receptors to the inducing ligands nor from measurable changes in conformation of the liganded receptors. Thus the single amino-acid exchanges identify differences in amino-acid-sequence requirements for transactivation and ligand binding in the hormone-binding domain of the androgen receptor. These results provide new insights into ligand-dependent transactivation, and form a framework for the search for effective antagonists to be used in prostate-cancer therapy.     

Does the cerebellum contribute to specific aspects of attention?

We present data on attentional and neuropsychological functions of 16 patients with focal cerebellar lesions (13 tumours, 3 haematomas) compared to normative test data, and to 11 control subjects matched for age, gender, and years of education. Patients showed distinct deficits in qualitative aspects of a divided attention task, and in a working memory task. Performance in selective attention was unimpaired. The results support the concept that the cerebellum plays a role not only in motor, but also in higher cognitive functions. They are discussed on the basis of the idea that prediction and preparation are fundamental functions of the cerebellum. Therefore, the results confirm the idea that cerebellar lesions lead to reduced performance in specific attention tasks.     

Membrane association of myotubularin-related protein 2 is mediated by a pleckstrin homology-GRAM domain and a coiled-coil dimerization module

Mutations in the myotubularin (MTM)-related protein 2 (MTMR2) gene are responsible for the severe autosomal recessive neuropathy Charcot-Marie-Tooth disease type 4B1. MTMR2 belongs to the MTM family of dual-specific phosphatases that use phosphatidylinositol (PI) 3,5-bisphosphate [PI(3,5)P2] and PI 3-phosphate [PI(3)P] as their substrate. Because these substrates are localized in the membrane bilayer, membrane targeting of Mtmr2 is an important regulatory mechanism. In hypoosmotically stressed COS cells with increased levels of PI(3,5)P2, Mtmr2 is bound to the membrane of vacuoles formed under these conditions. Using several mutant forms of Mtmr2, we identified two domains that are necessary for membrane association: (i) A pleckstrin homology-GRAM domain; and (ii) a coiled-coil module. Protein-lipid overlay assays show that the pleckstrin homology-GRAM domain binds to PI(3,5)P2 and PI(5)P, a substrate and a product of the Mtmr2 enzyme, respectively. We also demonstrate that Mtmr2 forms a dimer and that the C-terminal coiled-coil is responsible for homodimerization, in addition to membrane association. Our data indicate that phosphoinositide-protein interactions, as well as protein-protein interactions, are necessary for the correct regulation of MTMR2.