971 resultados para Kaunda, K.D., Sambian presidentti


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In response to our suggestion to define substance use disorders via 'heavy use over time', theoretical and conceptual issues, measurement problems and implications for stigma and clinical practice were raised. With respect to theoretical and conceptual issues, no other criterion has been shown, which would improve the definition. Moreover, heavy use over time is shown to be highly correlated with number of criteria in current DSM-5. Measurement of heavy use over time is simple and while there will be some underestimation or misrepresentation of actual levels in clinical practice, this is not different from the status quo and measurement of current criteria. As regards to stigma, research has shown that a truly dimensional concept can help reduce stigma. In conclusion, 'heavy use over time' as a tangible common denominator should be seriously considered as definition for substance use disorder.

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Factor analysis as frequent technique for multivariate data inspection is widely used also for compositional data analysis. The usual way is to use a centered logratio (clr)transformation to obtain the random vector y of dimension D. The factor model istheny = Λf + e (1)with the factors f of dimension k & D, the error term e, and the loadings matrix Λ.Using the usual model assumptions (see, e.g., Basilevsky, 1994), the factor analysismodel (1) can be written asCov(y) = ΛΛT + ψ (2)where ψ = Cov(e) has a diagonal form. The diagonal elements of ψ as well as theloadings matrix Λ are estimated from an estimation of Cov(y).Given observed clr transformed data Y as realizations of the random vectory. Outliers or deviations from the idealized model assumptions of factor analysiscan severely effect the parameter estimation. As a way out, robust estimation ofthe covariance matrix of Y will lead to robust estimates of Λ and ψ in (2), seePison et al. (2003). Well known robust covariance estimators with good statisticalproperties, like the MCD or the S-estimators (see, e.g. Maronna et al., 2006), relyon a full-rank data matrix Y which is not the case for clr transformed data (see,e.g., Aitchison, 1986).The isometric logratio (ilr) transformation (Egozcue et al., 2003) solves thissingularity problem. The data matrix Y is transformed to a matrix Z by usingan orthonormal basis of lower dimension. Using the ilr transformed data, a robustcovariance matrix C(Z) can be estimated. The result can be back-transformed tothe clr space byC(Y ) = V C(Z)V Twhere the matrix V with orthonormal columns comes from the relation betweenthe clr and the ilr transformation. Now the parameters in the model (2) can beestimated (Basilevsky, 1994) and the results have a direct interpretation since thelinks to the original variables are still preserved.The above procedure will be applied to data from geochemistry. Our specialinterest is on comparing the results with those of Reimann et al. (2002) for the Kolaproject data

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Using ameba coculture, we grew a Naegleria endosymbiont. Phenotypic, genetic, and phylogenetic analyses supported its affiliation as Protochlamydia naegleriophila sp. nov. We then developed a specific diagnostic PCR for Protochlamydia spp. When applied to bronchoalveolar lavages, results of this PCR were positive for 1 patient with pneumonia. Further studies are needed to assess the role of Protochlamydia spp. in pneumonia.

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In this study, we quantitatively investigated the expression of beta-site amyloid precursor protein cleaving enzyme (BACE) in the entorhinohippocampal and frontal cortex of Alzheimer's disease (AD) and old control subjects. The semiquantitative estimation indicated that the intensity of BACE overall immunoreactivity did not differ significantly between AD and controls, but that a significantly stronger staining was observed in the hippocampal regions CA3-4 compared to other regions in both AD patients and controls. The quantitative estimation confirmed that the number of BACE-positive neuronal profiles was not significantly decreased in AD. However, some degeneration of BACE-positive profiles was attested by the colocalization of neurons expressing BACE and exhibiting neurofibrillary tangles (NFT), as well as by a decrease in the surface area of BACE-positive profiles. In addition, BACE immunocytochemical expression was observed in and around senile plaques (SP), as well as in reactive astrocytes. BACE-immunoreactive astrocytes were localized in the vicinity or close to the plaques and their number was significantly increased in AD entorhinal cortex. The higher amount of beta-amyloid SP and NFT in AD was not correlated with an increase in BACE immunoreactivity. Taken together, these data accent that AD progression does not require an increased neuronal BACE protein level, but suggest an active role of BACE in immunoreactive astrocytes. Moreover, the strong expression in controls and regions less vulnerable to AD puts forward the probable existence of alternate BACE functions.

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For glioblastoma (GBM), survival classification has primarily relied on clinical criteria, exemplified by the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA). We sought to improve tumor classification by combining tumor biomarkers with the clinical RPA data. To accomplish this, we first developed 4 molecular biomarkers derived from gene expression profiling, a glioma CpG island methylator phenotype, a novel MGMT promoter methylation assay, and IDH1 mutations. A molecular predictor (MP) model was created with these 4 biomarkers on a training set of 220 retrospectively collected archival GBMtumors. ThisMPwas further combined with RPA classification to develop a molecular-clinical predictor (MCP). The median survivals for the combined, 4-class MCP were 65 months, 31 months, 13 months, and 9 months, which was significantly improved when compared with the RPA alone. The MCP was then applied to 725 samples from the RTOG-0525 cohort, showing median survival for each risk group of NR, 26 months, 16 months, and 11 months. The MCP was significantly improved over the RPA at outcome prediction in the RTOG 0525 cohort with a 33%increase in explained variation with respect to survival, validating the result obtained in the training set. To illustrate the benefit of the MCP for patient stratification, we examined progression-free survival (PFS) for patients receiving standard-dose temozolomide (SD-TMZ) vs. dose-dense TMZ (DD-TMZ) in RPA and MCP risk groups. A significant difference between DD-TMZ and SD-TMZ was observed in the poorest surviving MCP risk group with a median PFS of 6 months vs. 3 months (p ¼ 0.048, log-rank test). This difference was not seen using the RPA classification alone. In summary, we have developed a combined molecular-clinical predictor that appears to improve outcome prediction when compared with clinical variables alone. This MCP may serve to better identify patients requiring intensive treatments beyond the standard of care.

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Radiotherapy with concomitant and adjuvant TMZ is the standard of care for newly diagnosed GBM. MGMT methylation status may be an important determinant of treatment response. This trial, conducted by the RTOG, EORTC, and NCCTG, determined if intensified TMZ improves survival (OS) or progression free survival (PFS) in all patients or specific to MGMT status. Eligibility criteria included age . 18 yrs, KPS ≥ 60, and existence of a tissue block with . 1cm2 tumor for prospective MGMT and retrospective molecular analysis. Patients were randomized to Arm 1: standard TMZ (150-200 mg/m2 x 5 d) or Arm 2: dd TMZ (75-100 mg/m2 x 21 d) q 4 wks for 6-12 cycles. Symptom burden, quality of life (QOL), and neurocognition were prospectively and longitudinally assessed in a patient subset. 833 patients were randomized (1173 registered). Inadequate tissue (n ¼ 144) was the most frequent reason for nonrandomization.No statistical difference was observed between Arms 1 and 2 for median OS (16.6, 14.9 mo, p ¼ 0.63), median PFS (5.5, 6.7 mo, p ¼ 0.06), or methylation status. MGMT methylation was associated with improved OS (21.2, 14 mo, p , 0.0001), PFS (8.7, 5.7 mo, p , 0.0001), and treatment response (p ¼ 0.012). Cox modeling identifiedMGMT status and RPA class as significant predictors of OS; treatment arm and radiation technique (EORTC vs. RTOG) were not. There was increased grade ≥ 3 toxicity in Arm 2 (19%, 27%, p ¼ 0.008), which was mostly lymphopenia and fatigue. This study did not demonstrate improved efficacy for dd TMZ for newly diagnosed GBM regardless of methylation status. However, it confirmed the prognostic significance of MGMT methylation in GBM, demonstrated the feasibility of tumor tissue collection, molecular stratification, and collection of patient outcomes in a large transatlantic intergroup trial, thereby establishing a viable clinical trial paradigm. Support: NCI U10 CA 21661 and U10 CA37422.

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In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.

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Little is known about the relation between the genome organization and gene expression in Leishmania. Bioinformatic analysis can be used to predict genes and find homologies with known proteins. A model was proposed, in which genes are organized into large clusters and transcribed from only one strand, in the form of large polycistronic primary transcripts. To verify the validity of this model, we studied gene expression at the transcriptional, post-transcriptional and translational levels in a unique locus of 34kb located on chr27 and represented by cosmid L979. Sequence analysis revealed 115 ORFs on either DNA strand. Using computer programs developed for Leishmania genes, only nine of these ORFs, localized on the same strand, were predicted to code for proteins, some of which show homologies with known proteins. Additionally, one pseudogene, was identified. We verified the biological relevance of these predictions. mRNAs from nine predicted genes and proteins from seven were detected. Nuclear run-on analyses confirmed that the top strand is transcribed by RNA polymerase II and suggested that there is no polymerase entry site. Low levels of transcription were detected in regions of the bottom strand and stable transcripts were identified for four ORFs on this strand not predicted to be protein-coding. In conclusion, the transcriptional organization of the Leishmania genome is complex, raising the possibility that computer predictions may not be comprehensive.

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A recombinant baculovirus expressing the murine class I MHC heavy chain H-2Kd cDNA under the transcriptional control of Autografa californica nuclear polyhedrosis virus (AcNPV) polyhedrin promoter has been isolated and used to infect Sf9 lepidopteran cells either alone or in association with a previously isolated virus expressing mouse beta 2-microglobulina (beta 2-ma). When infected with the heavy chain-encoding virus alone, H-2Kd was produced in a beta 2-m-free conformation detected on the surface of infected cells by conformation-independent antibodies. When Sf9 cells were co-infected with both viruses, approximately 10% of the heavy chain pool was engaged in the formation of native heterodimeric MHC class I molecules, which were glycosylated and transported to the cell surface as demonstrated by radio-binding experiments and flow cytometry. The assembly of the recombinant class I molecule was dependent on peptide, since heterodimer formation was brought about by H-2Kd-specific peptide ligands both in vivo, upon incubation with dually infected cells, and in vitro, in cell-free detergent extracts. In addition, a change in heavy chain conformation was brought about upon incubation with high concentrations (100 microM) of an H-2Kd-restricted octapeptide epitope from Plasmodium berghei. Furthermore, using low concentrations (3 nM) of a photoaffinity label derivative of this peptide, we show direct binding to cells co-expressing class I heavy chain and mouse beta 2-m but not to cells expressing free heavy chain only.

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BACKGROUND: The goals of our study are to determine the most appropriate model for alcohol consumption as an exposure for burden of disease, to analyze the effect of the chosen alcohol consumption distribution on the estimation of the alcohol Population- Attributable Fractions (PAFs), and to characterize the chosen alcohol consumption distribution by exploring if there is a global relationship within the distribution. METHODS: To identify the best model, the Log-Normal, Gamma, and Weibull prevalence distributions were examined using data from 41 surveys from Gender, Alcohol and Culture: An International Study (GENACIS) and from the European Comparative Alcohol Study. To assess the effect of these distributions on the estimated alcohol PAFs, we calculated the alcohol PAF for diabetes, breast cancer, and pancreatitis using the three above-named distributions and using the more traditional approach based on categories. The relationship between the mean and the standard deviation from the Gamma distribution was estimated using data from 851 datasets for 66 countries from GENACIS and from the STEPwise approach to Surveillance from the World Health Organization. RESULTS: The Log-Normal distribution provided a poor fit for the survey data, with Gamma and Weibull distributions providing better fits. Additionally, our analyses showed that there were no marked differences for the alcohol PAF estimates based on the Gamma or Weibull distributions compared to PAFs based on categorical alcohol consumption estimates. The standard deviation of the alcohol distribution was highly dependent on the mean, with a unit increase in alcohol consumption associated with a unit increase in the mean of 1.258 (95% CI: 1.223 to 1.293) (R2 = 0.9207) for women and 1.171 (95% CI: 1.144 to 1.197) (R2 = 0. 9474) for men. CONCLUSIONS: Although the Gamma distribution and the Weibull distribution provided similar results, the Gamma distribution is recommended to model alcohol consumption from population surveys due to its fit, flexibility, and the ease with which it can be modified. The results showed that a large degree of variance of the standard deviation of the alcohol consumption Gamma distribution was explained by the mean alcohol consumption, allowing for alcohol consumption to be modeled through a Gamma distribution using only average consumption.

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The glioma CpG island methylator phenotype (G-CIMP) has been shown to be highly correlated with prognosis andwas noted to be highly concordant with IDH1mutation in malignant glioma in the limited number of samples analyzed. To better understand the relationship of G-CIMP with IDH1 mutation status and patient outcome, we examined G-CIMP status in detail in a larger retrospective series of glioblastomas as well as tumor samples from the RTOG 0525 clinical trial. Sampleswere tested for 6 CIMPmarkers andwere correlated with patient outcomes. In the retrospective tumor set (n ¼ 301),we found 3 distinct survival groups based on the number of CIMP markers: 0-1 (CIMP-negative), 2-4 (CIMP-intermediate), and 5 or greater (CIMP-positive) with median survivals 13.8, 20.1, and 90.6 months, respectively. This finding was validated in the RTOG 0525 samples (median survivals 15.0, 20.3, and 37.0 months). Among 787 cases with both IDH and CIMP data, 617 were CIMP-negative, 136 were CIMP-intermediate, and 34 were CIMP-positive. Seven hundred forty-four were wild type for IDH1 mutation, and 43 were mutant. CIMP and IDH status were positively correlated but outliers were found. Among the 610 CIMP-negative tumors, there were 7 IDH-mutant tumors, which showed no difference in outcome. Similarly, among the 34 CIMP-positive tumors, there were 21 IDH-mutant cases, which also showed no difference in outcome. However, among the CIMP-intermediate cases, there were 15 IDH-mutant cases with significantly (p ¼ 0.0003) improved outcome (medians not reached vs. 18.5 months, 2 year survival 87% vs. 32%). Multivariate analysis showed that both IDH1 mutation status and CIMP status were independent predictors of outcome. These findings suggest the clinical utility of refining the CIMP status into negative, intermediate, and positive groups and the finding that both IDH1 and CIMPstatus are important molecular markers in GBM.

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AIMS: This study aimed to estimate the prevalence of life-time abstainers, former drinkers and current drinkers, adult per-capita consumption of alcohol and pattern of drinking scores, by country and Global Burden of Disease region for 2005, and to forecast these indicators for 2010. DESIGN: Statistical modelling based on survey data and routine statistics. SETTING AND PARTICIPANTS: A total of 241 countries and territories. MEASUREMENTS: Per-capita consumption data were obtained with the help of the World Health Organization's Global Information System on Alcohol and Health. Drinking status data were obtained from Gender, Alcohol and Culture: An International Study, the STEPwise approach to Surveillance study, the World Health Survey/Multi-Country Study and other surveys. Consumption and drinking status data were triangulated to estimate alcohol consumption across multiple categories. FINDINGS: In 2005 adult per-capita annual consumption of alcohol was 6.1 litres, with 1.7 litres stemming from unrecorded consumption; 17.1 litres of alcohol were consumed per drinker, 45.8% of all adults were life-time abstainers, 13.6% were former drinkers and 40.6% were current drinkers. Life-time abstention was most prevalent in North Africa/Middle East and South Asia. Eastern Europe and Southern sub-Saharan Africa had the most detrimental pattern of drinking scores, while drinkers in Europe (Eastern and Central) and sub-Saharan Africa (Southern and West) consumed the most alcohol. CONCLUSIONS: Just over 40% of the world's adult population consumes alcohol and the average consumption per drinker is 17.1 litres per year. However, the prevalence of abstention, level of alcohol consumption and patterns of drinking vary widely across regions of the world.

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Background: Gout patients initiating urate lowering therapy have an increased risk of flares. Inflammation in gouty arthritis is induced by interleukin (IL)-1b. Canakinumab inhibits IL-1b effectively in clinical studies. This study compared different doses of canakinumab vs colchicine in preventing flares in gout patients initiating allopurinol therapy.Methods: In this 24 wk double blind study, gout patients (20-79 years) initiating allopurinol were randomized (1:1:1:1:1:1:2) to canakinumab s.c. single doses of 25, 50, 100, 200, 300 mg, or 150mg divided in doses every 4 wks (50þ50þ25þ25mg [q4wk]) or colchicine 0.5mg p.o. daily for 16 wks. Primary outcome was to determine the canakinumab dose giving comparable efficacy to colchicine with respect to number of flares occurring during first 16 wks. Secondary outcomes included number of patients with flares and C-reactive protein (CRP) levels during the first 16 wks.Results: 432 patients were randomized and 391 (91%) completed the study. All canakinumab doses were better than colchicine in preventing flares and therefore, a canakinumab dose comparable to colchicine couldn't be determined. Based on a negative binomialmodel, all canakinumab groups, except 25 mg, reduced the flare rate ratio per patient significantly compared to colchicine group (rate ratio estimates 25mg 0.60, 50mg 0.34, 100mg 0.28, 200mg 0.37, 300mg 0.29, q4wk 0.38; p_0.05). Percentage of patients with flares was lower for all canakinumab groups (25mg 27.3%, 50mg 16.7%, 100mg 14.8%, 200mg 18.5%, 300mg 15.1%, q4wk 16.7%) compared to colchicine group (44.4%). All patients taking canakinumab were significantly less likely to experience at least one gout flare than patients taking colchicine (odds ratio range [0.22 - 0.47]; p_0.05 for all). Median baseline CRP levels were 2.86 mg/L for 25 mg, 3.42 mg/L for 50 mg, 1.76 mg/L for 100 mg, 3.66 mg/L for 200 mg, 3.21 mg/L for 300 mg, 3.23 mg/L for q4wk canakinumab groups and 2.69 mg/L for colchicine group. In all canakinumab groups with median CRP levels above the normal range at baseline, median levels declined within 15 days of treatment and were maintained at normal levels (ULN¼3 mg/L) throughout the 16 wk period. Adverse events (AEs) occurred in 52.7% (25 mg), 55.6% (50 mg), 51.9% (100 mg), 51.9% (200 mg), 54.7% (300 mg), 58.5% (q4wk) of patients on canakinumab vs 53.7% of patients on colchicine. Serious AEs (SAE) were reported in 2 (3.6%; 25 mg), 2 (3.7%, 50 mg), 3 (5.6%, 100 mg), 3 (5.6%, 200 mg), 3 (5.7%, 300 mg), 1 (1.9%, q4wk) patients on canakinumab and in 5 (4.6%) patients on colchicine. 1 fatal SAE (myocardial infarction, not related to study drug) occurred in colchicine group.Conclusions: In this randomized, double-blind active controlled study of flare prevention in gout patients initiating allopurinol therapy, treatment with canakinumab led to a statistically significant reduction in flares compared with colchicine and was well tolerated.Disclosure statement: U.A., A.B., G.K., D.R. and P.S. are employees of and have stock options or bold holdings with Novartis Pharma AG. E.M. is a principal investigator for Novartis Pharmaceuticals Corporation. E.N. has received consulting fees from Roche. N.S. has received research grants from Novartis Pharmaceuticals Corporation. A.S. has received consultancy fees from Novartis Pharma AG, Abbott, Bristol-Myers Squibb, Essex, Pfizer, MSD, Roche, UCB and Wyeth. All other authors have declared no conflicts of interest.