928 resultados para Classical correlation


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The lengths of the male genital filaments and female spermathecal ducts were measured in phlebotomine sand flies of the Lutzomyia intermedia species complex and the ratios between these characters calculated. Ratios for L. intermedia s. s. from Northeast vs Southeast Brazil (Espírito Santo and Minas Gerais), Espírito Santo/Minas Gerais vs Rio de Janeiro/São Paulo and L. intermedia vs L. neivai were significantly different at P < 0.1, 0.05 and 0.01 respectively when compared using ANOVA. The spermathecal ducts and genital filaments of L. intermedia were significantly longer than those of L. neivai (P < 0.01) and could be used to differentiate these species. The taxonomic and biological significance of these differences is discussed.

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The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results.

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Background: The imatinib trough plasma concentration (C(min)) correlates with clinical response in cancer patients. Therapeutic drug monitoring (TDM) of plasma C(min) is therefore suggested. In practice, however, blood sampling for TDM is often not performed at trough. The corresponding measurement is thus only remotely informative about C(min) exposure. Objectives: The objectives of this study were to improve the interpretation of randomly measured concentrations by using a Bayesian approach for the prediction of C(min), incorporating correlation between pharmacokinetic parameters, and to compare the predictive performance of this method with alternative approaches, by comparing predictions with actual measured trough levels, and with predictions obtained by a reference method, respectively. Methods: A Bayesian maximum a posteriori (MAP) estimation method accounting for correlation (MAP-ρ) between pharmacokinetic parameters was developed on the basis of a population pharmacokinetic model, which was validated on external data. Thirty-one paired random and trough levels, observed in gastrointestinal stromal tumour patients, were then used for the evaluation of the Bayesian MAP-ρ method: individual C(min) predictions, derived from single random observations, were compared with actual measured trough levels for assessment of predictive performance (accuracy and precision). The method was also compared with alternative approaches: classical Bayesian MAP estimation assuming uncorrelated pharmacokinetic parameters, linear extrapolation along the typical elimination constant of imatinib, and non-linear mixed-effects modelling (NONMEM) first-order conditional estimation (FOCE) with interaction. Predictions of all methods were finally compared with 'best-possible' predictions obtained by a reference method (NONMEM FOCE, using both random and trough observations for individual C(min) prediction). Results: The developed Bayesian MAP-ρ method accounting for correlation between pharmacokinetic parameters allowed non-biased prediction of imatinib C(min) with a precision of ±30.7%. This predictive performance was similar for the alternative methods that were applied. The range of relative prediction errors was, however, smallest for the Bayesian MAP-ρ method and largest for the linear extrapolation method. When compared with the reference method, predictive performance was comparable for all methods. The time interval between random and trough sampling did not influence the precision of Bayesian MAP-ρ predictions. Conclusion: Clinical interpretation of randomly measured imatinib plasma concentrations can be assisted by Bayesian TDM. Classical Bayesian MAP estimation can be applied even without consideration of the correlation between pharmacokinetic parameters. Individual C(min) predictions are expected to vary less through Bayesian TDM than linear extrapolation. Bayesian TDM could be developed in the future for other targeted anticancer drugs and for the prediction of other pharmacokinetic parameters that have been correlated with clinical outcomes.

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BACKGROUND: After age, sex is the most important risk factor for coronary artery disease (CAD). The mechanism through which women are protected from CAD is still largely unknown, but the observed sex difference suggests the involvement of the reproductive steroid hormone signaling system. Genetic association studies of the gene-encoding Estrogen Receptor α (ESR1) have shown conflicting results, although only a limited range of variation in the gene has been investigated. METHODS AND RESULTS: We exploited information made available by advanced new methods and resources in complex disease genetics to revisit the question of ESR1's role in risk of CAD. We performed a meta-analysis of 14 genome-wide association studies (CARDIoGRAM discovery analysis, N=≈87,000) to search for population-wide and sex-specific associations between CAD risk and common genetic variants throughout the coding, noncoding, and flanking regions of ESR1. In addition to samples from the MIGen (N=≈6000), WTCCC (N=≈7400), and Framingham (N=≈3700) studies, we extended this search to a larger number of common and uncommon variants by imputation into a panel of haplotypes constructed using data from the 1000 Genomes Project. Despite the widespread expression of ERα in vascular tissues, we found no evidence for involvement of common or low-frequency genetic variation throughout the ESR1 gene in modifying risk of CAD, either in the general population or as a function of sex. CONCLUSIONS: We suggest that future research on the genetic basis of sex-related differences in CAD risk should initially prioritize other genes in the reproductive steroid hormone biosynthesis system.

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While the syncretistic Tibetan tradition known as rDzogs chen ("Great Perfection") has attracted considerable attention over the past few decades, its philosophical foundations remain largely unknown to those unacquainted with its primary sources. This thesis looks at the essentials of rDzogs chen philosophy through the lens of two principal distinctions that the tradition has considered indispensable for understanding its distinctive views and practices: dualistic mind (sems) versus primordial knowing (ye shes) and dharmakâya versus the 'ground of all' (kun gzhi) conditioned experience. Arguing that the distinctions provided classical rDzogs chen scholars with a crucial framework for (a) articulating the necessary conditions of nondual primordial knowing, the conditio sine qua non of rNying ma soteriology, and (b) schematizing the relationship between the exoteric and esoteric vehicles of Indian Buddhism within a unifying conception of the Buddhist path as the progressive disclosure of primordial knowing, the thesis shows how the rDzogs chen philosophy of mind has been integral to the tradition's complex soteriology. The thesis consists of two parts: (1) a detailed philosophical investigation of the distinctions and (2) an anthology of previously untranslated Tibetan materials on the distinctions accompanied by critical editions and introductions. The first part systematically invesigates the nature and scope of the distinctions and traces their evolution and complex relationships with Indian Buddhist Cittamâtra, Madhyamaka, Pramàriavàda, and Vajrayâna views. It concludes with an exploration of some soteriological implications of the mind/primordial knowing distinction that became central to rDzogs chen path hermeneutics in the classical period as authors of rDzogs chen path summaries used this distinction to reconcile progressivist sutric and non-progressivist tantric models of the Buddhist path. The translations and texts included in part two of the thesis consist of (a) a short treatise from Klong chen pa's Miscellaneous Writings entitled Sems dang ye shes kyi dris lan (Reply to Questions Concerning Mind and Primordial Knowing), (b) selected passages on the distinctions from this author's monumental summary of the rDzogs chen snying thig system, the Theg mchog mdzod (Treasury of the Supreme Vehicle), and (c) an excerpt on rDzogs chen distinctions taken from 'Jigs med gling pa's (1729-1798) 18th century Klong chen sNying thig path summary entitled Treasury of Qualities (Yon tan mdzod) along with a word-by- word commentary by Yon tan rgya mtsho (b. 19th c.).

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Measuring antibiotic-induced killing relies on time-consuming biological tests. The firefly luciferase gene (luc) was successfully used as a reporter gene to assess antibiotic efficacy rapidly in slow-growing Mycobacterium tuberculosis. We tested whether luc expression could also provide a rapid evaluation of bactericidal drugs in Streptococcus gordonii. The suicide vectors pFW5luc and a modified version of pJDC9 carrying a promoterless luc gene were used to construct transcriptional-fusion mutants. One mutant susceptible to penicillin-induced killing (LMI2) and three penicillin-tolerant derivatives (LMI103, LMI104, and LMI105) producing luciferase under independent streptococcal promoters were tested. The correlation between antibiotic-induced killing and luminescence was determined with mechanistically unrelated drugs. Chloramphenicol (20 times the MIC) inhibited bacterial growth. In parallel, luciferase stopped increasing and remained stable, as determined by luminescence and Western blots. Ciprofloxacin (200 times the MIC) rapidly killed 1.5 log10 CFU/ml in 2-4 hr. Luminescence decreased simultaneously by 10-fold. In contrast, penicillin (200 times the MIC) gave discordant results. Although killing was slow (&lt; or = 0.5 log10 CFU/ml in 2 hr), luminescence dropped abruptly by 50-100-times in the same time. Inactivating penicillin with penicillinase restored luminescence, irrespective of viable counts. This was not due to altered luciferase expression or stability, suggesting some kind of post-translational modification. Luciferase shares homology with aminoacyl-tRNA synthetase and acyl-CoA ligase, which might be regulated by macromolecule synthesis and hence affected in penicillin-inhibited cells. Because of resemblance, luciferase might be down-regulated simultaneously. Luminescence cannot be universally used to predict antibiotic-induced killing. Thus, introducing reporter enzymes sharing mechanistic similarities with normal metabolic reactions might reveal other effects than those expected.

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Telomerase activity (TA) is detected in most human cancers but, with few exceptions, not in normal somatic cells. Little is known about TA in soft tissue tumors. We have examined a series of benign and malignant soft tissue tumors for TA using the telomerase repeat amplification protocol assay. Analysis of the expression of the human telomerase reverse transcriptase was also carried out using RT-PCR. TA was undetectable in benign lesions (15 of 15) and low-grade sarcomas (6 of 6) and was detectable in 50% (19 of 38) of intermediate-/high-grade sarcomas. Although the presence of TA in soft tissue tumors is synonymous with malignancy, it is neither a reliable method in making the distinction between reactive/benign and malignant (especially low-grade) lesions nor a reliable marker of tumor aggressiveness. Leiomyosarcomas and storiform/pleomorphic malignant fibrous histiocytomas rarely showed TA, irrespective of their grade. A strong correlation between human telomerase reverse transcriptase mRNA expression and TA was observed, supporting the close relationship between both parameters. No significant relationship was observed between proliferative activity (as assessed by MIB-1 immunolabeling) and TA. We verified that the absence of telomerase expression was not due to the presence of telomerase inhibitors and therefore alternative mechanism(s) for cell immortalization, yet to be determined, seem to be involved in the development and/or maintenance of some soft tissue sarcomas.

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Purpose: To identify patterns of initially pain freedom response in patients with classical trigeminal neuralgia (CTN) with Gamma Knife surgery (GKS) and to compare their associated hypoesthesia and recurrence rates. Methods: In this study we analysed only 497 patients treated between July 1992 and November 2010, with a follow-up longer than 1 year, after excluding megadolichobasilar artery and multiple sclerosis related trigeminal neuralgia, as well as the second GKS treatments so as to have only cases with CTN and single radiosurgical treatment. GKS using a Gamma Knife (model B or C or Perfexion) was performed, based on both MRI and computer tomography (CT) targeting. A single 4-mm isocenter was positioned in the cisternal portion of the trigeminal nerve at a median distance of 7.8 mm (range 4.5-14) anteriorly to the emergence of the nerve. A median maximum dose of 85 Gy (range 70-90) was delivered. After empiric methods but also by using a chart with clear cut-off periods of pain free distribution, we were able to divide the initially pain free patients into 3 separate groups: within the first 48 hours, after 48 hours till 30 days and after 30 days, respectively. Results: The median follow- up period was 43.75 months (range 12-174.41). Four hundred and fifty-four patients (91.75%) were initially pain free in a median time of 10 days (range 1-459): 169 (37.2%) became pain free within the first 48 hours (pf<=48 h), compared to 194 (42.8%) between the 3-rd day and the day 30 (pf (>48 h, <=30 d)), inclusively and 91 (20%) patients after 30 days (pf>30d). Differences in terms of postoperative hypoesthesia were found with a p value of 0.014 as follows: the group pf<=48 h had 18 (13.7%) compared to pf (>48 h, <=30 d) with 30 (19%) and pf>30d with 22 (30.5%) patients developing a postoperative GKS hypoesthesia. One hundred and fifty seven (34.4%) patients initially pain free experienced a recurrence with a median delay of 24 months (range 0.62-150.06). There were no statistically significant differences between the three groups concerning recurrence (p value of 0.515). Conclusions: An important number of patients (169 cases, 37.2%) became pain free in the first 48 hours. Hypoesthesia rate was higher within the group becoming pain free after 30 days with a statistically significant difference between the three populations (p= 0.014). Further analysis will eventually help to elucidate the differences observed among groups.

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Introduction: CD22 is expressed on most B-non-Hodgkin lymphomas (NHL); inotuzumab ozogamicin (INO) is an anti-CD22 antibody conjugated to calicheamicin. This study evaluated the safety and tolerability of INO plus R-CVP in patients (pts) with relapsed/refractory CD22+ B-NHL. Efficacy data were also collected. Methods: Part 1 of this open-label study identified a maximum tolerated dose (MTD) of INO 0.8mg/m,2 on day 2 plus R-CVP (rituximab 375mg/m,2 cyclophosphamide 750mg/m,2 and vincristine 1.4mg/m,2 on day 1; prednisone 40mg/m,2 on days 1-5) every 21 days. Subsequently, pts were enrolled in the MTD confirmation cohort (part 2, n = 10), which required a dose-limiting toxicity rate of <33% in cycle 1 and <4 pts discontinuing prior to cycle 3 due to an adverse event (AE) in the MTD expansion cohort (part 3, n = 22), which explored preliminary activity. Results: Parts 2 and 3 enrolled 32 pts: 16 pts with diffuse large B-cell lymphoma, 15 with follicular lymphoma and one with mantle cell lymphoma. Median age was 64.5 years (range 44-81 years); 34% of pts had 1 prior regimen, 34% had 2, 28% had ≥3 and 3% had none (median 2; range 0-6).Median treatment duration was five cycles (range 1-6). Part 2 confirmed the MTD as standard dose R-CVP plus INO 0.8mg/m,2; 2/10 pts had a dose-limiting toxicity (grade 3 increased ALT/AST, grade 4 neutropenia requiring G-CSF). One pt discontinued because of an AE prior to cycle 3. Common treatment-related AEs were thrombocytopenia (78%), neutropenia (66%), fatigue (50%), leukopenia (50%), nausea (41%) and lymphopenia (38%); common grade 3/4 AEs were neutropenia (63%), thrombocytopenia (53%), leukopenia (38%) and lymphopenia (31%). There was one case of treatment-related fatal pneumonia with grade 4 neutropenia. Ten pts discontinued treatment due to AEs; thrombocytopenia/delayed platelet recovery was the leading cause (grade 1/2, n = 6; grade 3/4, n = 3). Objective response rate (ORR) was 77% (n = 24/31 evaluable pts), including 26% (n=8/31) with complete response (CR); three pts had stable disease. Of the pts with follicular lymphoma, ORR was 100% (n = 15/15), including seven pts with CR. Of the pts with diffuse large B-cell lymphoma, ORR was 60% (n = 9/16), including one pt with CR. Conclusions: Results suggest that INOplus R-CVP has acceptable toxicity and promising activity in relapsed/refractory CD22+ B-NHL. The most common grade 3/4 AEs were hematologic. Follow-up for progression-free and overall survival is ongoing.

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The goals of the present study were to evaluate the kinetics of blood parasitism by examination of fresh blood, blood culture (BC) and PCR assays and their correlation with heart parasitism during two years of infection in Beagle dogs inoculated with the Be-78, Y and ABC Trypanosoma cruzi strains. Our results showed that the parasite or its kDNA is easily detected during the acute phase in all infected animals. On the other hand, a reduced number of positive tests were verified during the chronic phase of the infection. The frequency of positive tests was correlated with T. cruzi strain. The percentage of positive BC and blood PCR performed in samples from animals inoculated with Be-78 and ABC strains were similar and significantly larger in relation to animals infected with the Y strain.Comparison of the positivity of PCR tests performed using blood and heart tissue samples obtained two years after infection showed two different patterns associated with the inoculated T. cruzi strain: (1) high PCR positivity for both blood and tissue was observed in animals infected with Be-78 or ABC strains; (2) lower and higher PCR positivity for the blood and tissue, respectively, was detected in animals infected with Y strains. These data suggest that the sensitivity of BC and blood PCR was T. cruzi strain dependent and, in contrast, the heart tissue PCR revealed higher sensitivity regardless of the parasite stock.

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Sequence variation among different hepatitis C virus (HCV) isolates has adaptive significance and reflects the modes and intensities of selection mechanisms operating on the virus. In this work, we sought to investigate using classical population genetics parameters, the genetic variability of HCV genotype 1 using the 5' UTR and NS5A regions from treatment non-responding and responding groups of patients. Both regions showed low genetic varia-bility and the 5' UTR showed neutral deviation. No differences were observed in the nonsynonymous/synonymous nucleotide substitution ratio among groups for NS5A. The analysis of molecular variance test of the 5' UTR region showed an 11.94% variation among groups. Phylogenetic analysis showed no correlation between sequence variations and therapeutic responses.