995 resultados para MEDIAN EMINENCE
Resumo:
The indices found are analysed as a whole and general conclusions are drawn from them which may be of use in understanding many of the problems offered by the local flora (Ilhéus). The first column of the tables presented indicates the biological form of the species, showing the nature of the flora and the constitution of the climax. A total of 200 species of phanerophyta were found; 69 macrophanerophyta (trees), 54 are mesophanerophyta (treelets) and 77 are nanophanerophyta (shrubs). The macrophanerophyta are consequently considered as dominants and the meso-and nanophanerophyta as codominants (the biological forms: chamaephyta, hemicriptophyta, criptophyta, geophyta, therophyta, epiphyta and hydrophyta are subdominants), the more so as the first cover 80% and the others more or less 50%. This points to a climax of trees and a local vegetation mainly composed of trees also. The smaller forms are left out as they are beyond the present scope of this sort of wort in Brazil. The third column of ecological formulae indicates the reaction of the constituent species to light (C = sciophilous, F = photophilous and I = indifferents), the biological types of vegetation (H = hygrophytes, X = xerophytes and M = mesophytes) and the fidelity of the species to the climax. Of the species studied: 25 are pioneers (P. Table I), 63 are accidentals (A. Table II), 35 are companion species (O. Table III), 19 show preferences (E. Table with vitality Vn), 44 are selective (S. Table V) and 13 exclusive species (L. Table VI). This leads to the conclusion that the vegetation of the region is in full reconstitution. As to the ecological characteristics of the 200 species studied, 89 are either pioneers (a class separated by the author) or accidentals; this means that the devastated zones are being reconstituted in the subsere both with members of the prisere and alien species. Of the remaining species, 54 are companion, or accompanying species, which appear in most subclimax, serclímax and quasiclimax associations, and 57 are real constituents of the local climax. As all the species except the pioneers, selectives and exclusives (xerophytes and mesophytes) may be considered as hygrophytes this type evidently predominantes in the region and may constitute a hygrophilous serclimax and quasiclímax. In regard to light 101 are sciophilous, 32 indiferents and 67 photophilous. This leads to the conclusion that the vegetation comprises mainly tolerant species, showing the hygrophilous and mesophilous character of the region with a vegetation composed mostly of trees. The presence a large number of sciophilous species is easy to understand as the hygrophilous and mesophilous habitats and the dominance of trees favour the germination and growth of tolerant species. The last two columns analyse the percentage of individuals present and the occurrent classes to which they belong: 92 species vary between 1 and 9%; 50 between to 10 and 19%; 36 between 20 and 29%; 14 between 30 and 39%; and 8 between 40 and 49%. Only 8 species belong to occurrence class V; 14 to classe IV; 36 to class III; 50 to class II; and 92 to class I. This leads to the conclusion that the local formation is very unsociable and very complex, though the median coverture is 80% and the number of species is very large. The analysis of the data also shows that the climax is being reconstituted in the subsere with elements drawn from the prisere and alien species introduced either by man (following desvastation) or by other consequent factors (such as brusque changes of microclimates due to total or partial destruction). This modifies the subclimax appreciably and apparently also the climax of the local regional subsere. As a final conclusion it is suggested that as in the subsere the pioneer formation is xerophilous, the prisere also beging as a xerosere; but as there are and probably always were hydrophilous formation evolving in the same climate, the local climax is composed of species with medium exactions, that is of relative mesophites.
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The A. remembers the history of his lepra-culture and the method he uses to prepare with it the antigen called Leprolin Souza-Araujo, giving photographic illustrations upon the subject. The A. says that the results published about the general action of his Leprolin in leprosy must be revised or rectificated. But he says that the rapid action of his antigen upon perforant ulcers in lepers is consecrated by a large experience. He cured, in relatively short time, perforant ulcers in five lepers. Dr. CASSIANO, from Baurú leper Colony (S. Paulo) treated 21 such cases. The median time of treatment was 23 days and the median dosage of Leprolin injected in each patient was 7.7 cm3. All lesions were cured. After 18 months observation three cases relapsed and 18 (or 85.7%) remained cured. Dr. CALDEIRA, Director of padre DAMIEN Leper Colony (Ubá, Minas Gerais) treated regularly with Leprolin 50 cases of severe perforant ulcers and obtained cure in 46 (or 92%). ina special meeting held in Minas Gerais nineteen leprologists examined the cases of Dr. CALDEIRA and considered the results he have obtained as "magnifico", in the sense as "unic". This experiment is being continued in various brazilian leper colonies and the Author offers, graciously, his antigen to be tried also in foreing countries.
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A new tick, Amblyomma parkeri, n. sp., is described as a parasite of Coendu sp. from S. Paulo, Brazil. Female holotype, nymph and larva are described (Figs. 2 e 3). The n. sp. differs completly from Koch's species Amblyomma longirostre, the common parasite of the Erethizotidae. Standard data for measures of the female dorsal scutum ixodidae are proposed as follows (fig. 1): PA = Antero-posterior; PB = Postero-basal; PM = Postero-median; TT = Transversal; OO = Inter-ocular; OT= Occulo-transversal; SS = Inter-scapular; CC = Cervical; PT = Postero-transversal; ST = Scapulo-transversal; NPT = Normal to the postero-transversal; NST = Normal to the scapulo-transversal. In the female holotype the standard data are as follows: PA = 2.00 mm; PB = 2.26 mm; PM = 1.10 mm; TT = 2.20 mm; OO = 2.26 mm; SS = 0,84 mm; CC = 0.63 mm; SC = 0.12 mm; NPT = 0.20mm; STN = 0.1 mm. Peritrema 0.80 x 0.42 mm with a narrow postero-internal angle and a large, elongated macula. Coxa I with two short spines and all other coxae with only one shorter spine, shortest in coxa IV. Hypostoma spatulated with formula 3/3. Gnathosoma 1.42 mm long and basis 0.63 mm long by 0.84 greatest wide. Palpi with smoth external surface, 1.00 mm long. Type lot No. 4458 from Cotia, S. Paulo, Brazil; in the acarological collection of the Escola Paulista de Medicina, S. Paulo. Ixodes didelphidis, n. sp., differing from Ixodes loricatus Neumann by the shape of the peritremata (figs. 4 a 5) of the male and female and by the number of the punctations in this organ is described form Didelphidae, Muridae and Cavidae. Twenty eight lots were obtained from Anápolis, Goiás, Brasil, where I. loricatus is subtituded by the n. sp. under description. Comparison with NEUMANN'S types of I. loricatus was possible through the courtesy of Prof. A. BRIZARD from Toulouse, who kindly loaned NEUMANN'S material. Female cotypes N° 40 and male allotype N° 531 in the Collection of Ixodidae of the Oswaldo Cruz Institute.
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This paper examines competition in a spatial model of two-candidate elections, where one candidate enjoys a quality advantage over the other candidate. The candidates care about winning and also have policy preferences. There is two-dimensional private information. Candidate ideal points as well as their tradeoffs between policy preferences and winning are private information. The distribution of this two-dimensional type is common knowledge. The location of the median voter's ideal point is uncertain, with a distribution that is commonly known by both candidates. Pure strategy equilibria always exist in this model. We characterize the effects of increased uncertainty about the median voter, the effect of candidate policy preferences, and the effects of changes in the distribution of private information. We prove that the distribution of candidate policies approaches the mixed equilibrium of Aragones and Palfrey (2002a), when both candidates' weights on policy preferences go to zero.
Resumo:
When two candidates of different quality compete in a one dimensional policy space, the equilibrium outcomes are asymmetric and do not correspond to the median. There are three main effects. First, the better candidate adopts more centrist policies than the worse candidate. Second, the equilibrium is statistical, in the sense that it predicts a probability distribution of outcomes rather than a single degenerate outcome. Third, the equilibrium varies systematically with the level of uncertainty about the location of the median voter. We test these three predictions using laboratory experiments, and find strong support for all three. We also observe some biases and show that they canbe explained by quantal response equilibrium.
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This paper studies the stability of a finite local public goods economy in horizontal differentiation, where a jurisdiction's choice of the public good is given by an exogenous decision scheme. In this paper, we characterize the class of decision schemes that ensure the existence of an equilibrium with free mobility (that we call Tiebout equilibrium) for monotone distribution of players. This class contains all the decision schemes whose choice lies between the Rawlsian decision scheme and the median voter with mid-distance of the two median voters when there are ties. We show that for non-monotone distribution, there is no decision scheme that can ensure the stability of coalitions. In the last part of the paper, we prove the non-emptiness of the core of this coalition formation game
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C. delectus sp. n., found in Sepetiba Bay, characterizes by the following peculiarities: ovoid outline; apical system slightly anterior; petals with 2-4 interplates and 3-4 interporiferous primary tubercles. The pits in the naked median space are: 20 pits in 10 mm. Test low (height by length 0,45).
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Twelve species of the genus Archytas Jennicke, 1867, eight of which described as new are studied and figured in detail. Definitions of the species are based mainly on characters of male genitalia. The male genital characters are the most significant for separation of the species and most demonstrative of their affinities. By examining a long series of species of this genus we came to the conclusion that the presence of one pair of median marginal bristles on the third abdominal tergite seems to be characteristic of the genus. This caracter apparently so important, is not however considered fundamental. The most significant example is found in Archytas lenkoi sp. n. and Archytas vexor Curran, 1928. In A. lenkoi we can find one or two pairs or thay may, less frquently, be absent. In A. vexor these bristles are lacking. The shape of the male copulatory apparatus of Jurinia nitidiventris Curran, 1928 refered to by CURRAN in his "Revision of Archytas", is not characteristic of any species of the group and so, is not considered in this paper. To help in the identification, the species studied here are divided into groups. The analis group" includes: A. apicifer (Walker, 1894), A. californiae (Walker, 1856), A. nivalis Curran, 1928, a. giacomellii (Blanchard, 1941), A. basifulvus (Walker, 1849), A. incasanus Townsend, 1912 and A. cirphis Curran, 1927. The identification of members of these group is extremely difficult owing both to their similarity in colour pattern and to their variability. They all have black testaceous or dark brown abdomen, the last segment pale or brownish pollinose; second segment without bristles; third with a pair of strong marginals, fourth and fifth with two rows of discals on apical third. The final determination often rests upon the structure of the male copulatory apparatus. Fortunately in this group, many of the forcipes superiores and palpi genitalium are strikingly different from one another. The "zikani group" includes: A. zikani sp. n., A seabrai sp. n., A. duckei sp. n. and A. vernalis Curran, 1928. This group may be characterized as follows: forcipes interiores absent; forcipes superiores strongly chitinized an dilated at anex. Within this group, the forcipes of. A. seabrai sp. n. do not present an aberrant form. The "dissimilis group" will be studied in forthcoming papers. The limits of the genus Archyta Jaen. are not as yet sharply difined, the evaluation of the significance of each character used in the definition remaining as most difficult problem. The distinction between Archytas and other related genera is very difficult, chiefly because it is based on variable characters. In this paper we place the genera Parafabricia Towsend, 1931, Itachytas Blanchard, 1940, Archynemochaeta Blanchard, 1941, Proarchytoides Blanchard, 1941 and Archytodejeania Blanchard, 1941 in the synonymy of Archytas Jaen. The detailed examination of the characters used in their definition, proved them to be fundamentally proposed on basis of chaetotasy, these characters alone being precarious, because of the considerabel intraspecifical variation. The type of the new species are in the Oswaldo Cruz Institute collection. Rio de Janeiro, Brazil, and paratypes in the collections of the followings institutions: Departamento de Zoologia da Secretaria de Agricultura do Estado de São Paulo; Instituto de Ecologia e Experimemtação Agrícolas; Departamento de Defesa Sanitária Vegetal; Campos Seabra collection; and Barbiellini collection.
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The first case of Kala-azar in Colombia was discovered in Soledad, S. Vicente do Chucuri, Dept. Santander, by Gast-Galvis who viscerotomized a three year old girl deceased in December, 1943. In 1944, fifty-three Phlebotominae were collected in the chicken pen of the girl's house, two new species included. Mangabeira helped by A. Gast Galvis, Juan Antonio Montoya and E. Osorno Mesa, collected some Phlebotomus in that country. The geographical distribution of the species of Phlebotomus collected in Colombia (P. abonnenci, P. camposi, P. columbianus, P. dubitans, P. gasti, P. montoyai, P. saulensis, P. serranus, P. triramulus) and two species of Brumptomyia (B. beaupertuyi and b mesari), are included. our description of the male P. columbianus is based on some specimens found in association with females. However, doubts exist about such association of sexes. There is no correspondence between the length of the spicules and the ducts of spermathecae. Besides, the specimens were not obtained by raising. The following new species are described and compared with previously known ones: a) Phlebotomus gasti sp. n. differs from the other species by a protruding tubercle in the gubernaculum. It has also fewer setae in the tuft of the basistyle, a different length of the inferior gonapophyses, and a differently shaped clasper. b) Phlebotomus dubitans sp. n. differs from P. walkeri and P. deanei (according to personal information from O. Theodor, who examined the types, they are identical to P. williamsi and P. sericeus respectively), mainly because these species have the inferior gonapophyses larger than the basistyle and fewer setae in the basistyle. P. evandroi is separated by the shape of the claspers and by the tuft of setae of the basistyle. P. marajoensis is the closest relative to P. dubitans. There is a possibility of their being synonymous. On the other hand, they can be differentiated by the existence of three extra distal spines in P. marajoensis. There is also a difference in their palpal indexes: for marajoensis I - II - IV - III - V, and for dubitans I - IV (III - II) - V. We notice, too, that the inferior gonapophyses in P. marajoensis is a little shorter. P. marajoensis has a long seta in the basistyle (clearly shown in the original drawing), not found in the new species. c) Phlebotomus montoyai sp. n.: The closest relatives are P. noguchii, P. peruensis, P. pescei, P. quinquifer and P. rickardi. They differ from the new species by the number and length of the setae of the basistyle tuft which are more numerous and longer in the new species. The shapes of their claspers are also different. Other differences are: the basal portion of the basistyle in P. noguchii is very wide (in montoyai it is narrower); the intermediate spine of the dististyle is located on a protruding tubercle ( in the new species there is hardly a tubercle); the spicules are long, and the inferior gonapophyses is longer than the basistyle. P. quinquifer and P. rickardi have a shorter dististyle and narrower wings, with different venation. The main difference, however lies, in the M4, which ends almost at the level of the junction of M1 with M2 (in P. montoyai the M4 ends far behind). In P. peruensis and P. pescei the intermediary spine of the dististyle is closer to the distal spine than to the basal one, whereas in the new species it is situated between the two pairs. Their inferior gonapophyses is longer than the basistyle. d) Brumptomyia mesai sp. n. - Closest relatives are: B. hamatus, B. pentacanthus, B. beaupertuyi which are easily separated from the new species because the tufts of their basistyle have thin and differently shaped hairs. Also their claspers are shaped differently. B. avellari is also easily recognized on account of the twisted aspect of its clasper and because the basal tuft of the basistyle has few setae, B. brumpti tuft of setae arise directly from the basistyle; these setae are stronger than those of the new species. It has 8 blade-like setae located on the inner surface of the distal half, whereas the new species has only six setae. In B. brumpti, there are three median and two terminal spines in the dististyle; in the new species, there are two median and two terminal spines and one between them, which is closer to the two median spines. The comparison with B. galindoi is based in a specimen determined by Fairchild and deposited in the entomological collection of the "Faculdade de Higiene e Saúde Pública da Universidade de S. Paulo". The genitalia of the new species is much shorter, in galindoi the inferior gonapophyses is 0,8 mm long whereas in B. mesai it hardly reaches 0,6 mm. The shape of the clasper and the distribution of its setae are different. The sub-median lamellae, besides being longer in B. galindoi are also longer in comparison with the other parts of the genitalia. The gubernaculum of the new species is longer, thinner, and more pointed; in B. galindoi it is shorter and triangular. In the drawing published by Fairchild and Hertig 91947), the basistyle shows 8 blade-like setae on the distal half, whereas in the new species only six are found.
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The author studies 5 species of Archytas Jaennicke, 1867, belonging to the "dissimilis group": A. seminigra (Wiedemann, 1830) and four species which are considered as new. The species of this group may be characterized as follow: Species of short body, exceptionally large ones. Abdomen yellowish, with a median blackish V-shapedspot. Second antennal segment with 2/3 length of third. Parafacialia with blackish hairs. Propleura pilose. Post alar wall with few hairs. The following key facilitates the identification of the species: 1. Third article of antennae, strongly convex in the anterior margin (fig. 10); posterior margin straight. Parafacialia with a facio-orbital bristle well differentiated . . . . A. arnaudi sp. n. Third article of antennae not so convex in the anterior margin; facio-orbital bristle absent, if present not well differentiated [...] 2; 2. Parafrontalia with golden polen [...] 3; Parafrontalia brownish to shining black with few polen . . . 4; 3. Forcipes superiores slender and sub-truncate apically (figs. 5 and 6)[...] A. seminigra; Forcipes superiores broad apically (fig .20)[...] A, gongalvesi sp. n.; 4. First, second and third sternites yellowish [...] A. angrensis sp. n.; All sternites brownish to black [...] A. sabroskpi sp. n.; The material studied belongs to the Instituto Oswaldo Cruz collections, where is located the types of new species.
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Background: Cerebral cholinergic transmission plays a key role in cognitive function and anticholinergic drugs are associated with impaired cognitive functions [1]. In the perioperative phase many substances with anticholinergic effects are administered and disturbed cholinergic transmission is a hypothetical cause of postoperative cognitive dysfunction (POCD). Serum anticholinergic activity (SAA; pmol/ml) may be measured as a summary marker of anticholinergic activity in an individual patient's blood. We hypothesised that an increase in SAA from preoperatively to one week postoperatively is associated with POCD in elderly patients. Methods: Thirty-two patients aged >65 yrs undergoing elective major surgery under standardized general anaesthesia (thiopental, sevoflurane, fentanyl) were investigated. Cognitive functions were measured preoperatively and 7 days postoperatively using the extended version of the Consortium to Establish a Registry for Alzheimer's Disease - Neuropsychological Assessment Battery. POCD was defined as a postoperative decline >1 z-score in at least 2 cognitive domains. SAA was measured preoperatively and 7 days postoperatively at the time of cognitive testing. Results: 50% of the investigated patients developed POCD. There were no statistically significant differences between patients with and without POCD regarding age, education, baseline cognitive function, duration of anaesthesia, SAA preoperatively (median (range) 1.0 (0.3 to 5.0) vs 1.5 (0.4 to 5.0), SAA 7 days postoperatively (median (range) 1.3 (0.1 to 7.0) vs 1.4 (0.6 to 5.5) or changes in SAA (median (range) 0.1 (-1.6 to 2.2) vs 0.2 (-1.4 to 2.8). The variability of SAA in individual patients was considerable and marked changes in SAA between the two examinations were observed in some patients. However, there was no significant relationship between changes in SAA and changes in cognitive function. Conclusion: In this preliminary analysis of a small group of patients, changes in SAA in the perioperative phase were highly variable. SAA was not associated with POCD suggesting that POCD is not simply caused by anticholinergic medications administered in the perioperative phase. A further analysis of a larger group of patients is in progress.
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Reduced re'nal function has been reported with tenofovir disoproxil fumarate (TDF). It is not clear whether TDF co-administered with a boosted protease inhibitor (PI) leads to a greater decline in renal function than TDF co-administered with a non-nucleoside reverse transcriptase inhibitor (NNRTI).Methods: We selected ail antiretroviral therapy-naive patients in the Swiss HIV Cohort Study (SHCS) with calibrated or corrected serum creatinine measurements starting antiretroviral therapy with TDF and either efavirenz (EFV) or the ritonavir-boosted PIs, lopinavir (LPV/r) or atazanavir (ATV/r). As a measure of renal function, we used the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation to estimate the glomerular filtration rate (eGFR). We calculated the difference in eGFR over time between two therapies using a marginal model for repeated measures. In weighted analyses, observations were weighted by the product of their point of treatment and censoring weights to adjust for differences both in the sort of patients starting each therapy and in the sort of patients remaining on each therapy over time.Results: By March 2011, 940 patients with at least one creatinine measurement on a first therapy with either TDF and EFV (n=484), TDF and LPVlr (n=269) or TDF and ATV/r (n=187) had been followed for a median of 1. 7, 1.2 and 1.3 years, respectively. Table 1 shows the difference in average estimated GFR (eGFR) over time since starting cART for two marginal models. The first model was not adjusted for potential confounders; the second mode! used weights to adjust for confounders. The results suggest a greater decline in renal function during the first 6 months if TDF is used with a PI rather than with an NNRTI, but no further difference between these therapies after the first 6 months. TDF and ATV/r may lead to a greater decline in the first 6 months than TDF and LPVlr.Conclusions: TDF co-administered with a boosted PI leads to a greater de cline in renal function over the first 6 months of therapy than TDF co-administered with an NNRTI; this decline may be worse with ATV/r than with LPV/r.
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OBJECTIVE. The purpose of this study was to evaluate the prevalence of mesenteric venous thrombosis (MVT) in the Swiss Inflammatory Bowel Disease Cohort Study and to correlate MVT with clinical outcome. MATERIALS AND METHODS. Abdominal portal phase CT was used to examine patients with inflammatory bowel disease (IBD). Two experienced abdominal radiologists retrospectively analyzed the images, focusing on the superior and inferior mesenteric vein branches and looking for signs of acute or chronic thrombosis. The location of abnormalities was registered. The presence of MVT was correlated with IBD-related radiologic signs and complications. RESULTS. The cases of 160 patients with IBD (89 women, 71 men; Crohn disease [CD], 121 patients; ulcerative colitis [UC], 39 patients; median age at diagnosis, 27 years for patients with CD, 32 years for patients with UC) were analyzed. MVT was detected in 43 patients with IBD (26.8%). One of these patients had acute MVT; 38, chronic MVT; and four, both. The prevalence of MVT did not differ between CD (35/121 [28.9%]) and UC (8/39 [20.5%]) (p = 0.303). The location of thrombosis was different between CD and UC (CD, jejunal or ileal veins only [p = 0.005]; UC, rectocolic veins only [p = 0.001]). Almost all (41/43) cases of thrombosis were peripheral. MVT in CD patients was more frequently associated with bowel wall thickening (p = 0.013), mesenteric fat hypertrophy (p = 0.005), ascites (p = 0.002), and mesenteric lymph node enlargement (p = 0.036) and was associated with higher rate of bowel stenosis (p < 0.001) and more intestinal IBD-related surgery (p = 0.016) in the outcome. Statistical analyses for patients with UC were not relevant because of the limited population (n = 8). CONCLUSION. MVT is frequently found in patients with IBD. Among patients with CD, MVT is associated with bowel stenosis and CD-related intestinal surgery.
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Molecular monitoring of BCR/ABL transcripts by real time quantitative reverse transcription PCR (qRT-PCR) is an essential technique for clinical management of patients with BCR/ABL-positive CML and ALL. Though quantitative BCR/ABL assays are performed in hundreds of laboratories worldwide, results among these laboratories cannot be reliably compared due to heterogeneity in test methods, data analysis, reporting, and lack of quantitative standards. Recent efforts towards standardization have been limited in scope. Aliquots of RNA were sent to clinical test centers worldwide in order to evaluate methods and reporting for e1a2, b2a2, and b3a2 transcript levels using their own qRT-PCR assays. Total RNA was isolated from tissue culture cells that expressed each of the different BCR/ABL transcripts. Serial log dilutions were prepared, ranging from 100 to 10-5, in RNA isolated from HL60 cells. Laboratories performed 5 independent qRT-PCR reactions for each sample type at each dilution. In addition, 15 qRT-PCR reactions of the 10-3 b3a2 RNA dilution were run to assess reproducibility within and between laboratories. Participants were asked to run the samples following their standard protocols and to report cycle threshold (Ct), quantitative values for BCR/ABL and housekeeping genes, and ratios of BCR/ABL to housekeeping genes for each sample RNA. Thirty-seven (n=37) participants have submitted qRT-PCR results for analysis (36, 37, and 34 labs generated data for b2a2, b3a2, and e1a2, respectively). The limit of detection for this study was defined as the lowest dilution that a Ct value could be detected for all 5 replicates. For b2a2, 15, 16, 4, and 1 lab(s) showed a limit of detection at the 10-5, 10-4, 10-3, and 10-2 dilutions, respectively. For b3a2, 20, 13, and 4 labs showed a limit of detection at the 10-5, 10-4, and 10-3 dilutions, respectively. For e1a2, 10, 21, 2, and 1 lab(s) showed a limit of detection at the 10-5, 10-4, 10-3, and 10-2 dilutions, respectively. Log %BCR/ABL ratio values provided a method for comparing results between the different laboratories for each BCR/ABL dilution series. Linear regression analysis revealed concordance among the majority of participant data over the 10-1 to 10-4 dilutions. The overall slope values showed comparable results among the majority of b2a2 (mean=0.939; median=0.9627; range (0.399 - 1.1872)), b3a2 (mean=0.925; median=0.922; range (0.625 - 1.140)), and e1a2 (mean=0.897; median=0.909; range (0.5174 - 1.138)) laboratory results (Fig. 1-3)). Thirty-four (n=34) out of the 37 laboratories reported Ct values for all 15 replicates and only those with a complete data set were included in the inter-lab calculations. Eleven laboratories either did not report their copy number data or used other reporting units such as nanograms or cell numbers; therefore, only 26 laboratories were included in the overall analysis of copy numbers. The median copy number was 348.4, with a range from 15.6 to 547,000 copies (approximately a 4.5 log difference); the median intra-lab %CV was 19.2% with a range from 4.2% to 82.6%. While our international performance evaluation using serially diluted RNA samples has reinforced the fact that heterogeneity exists among clinical laboratories, it has also demonstrated that performance within a laboratory is overall very consistent. Accordingly, the availability of defined BCR/ABL RNAs may facilitate the validation of all phases of quantitative BCR/ABL analysis and may be extremely useful as a tool for monitoring assay performance. Ongoing analyses of these materials, along with the development of additional control materials, may solidify consensus around their application in routine laboratory testing and possible integration in worldwide efforts to standardize quantitative BCR/ABL testing.
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BACKGROUND: Cone-beam computed tomography (CBCT) image-guided radiotherapy (IGRT) systems are widely used tools to verify and correct the target position before each fraction, allowing to maximize treatment accuracy and precision. In this study, we evaluate automatic three-dimensional intensity-based rigid registration (RR) methods for prostate setup correction using CBCT scans and study the impact of rectal distension on registration quality. METHODS: We retrospectively analyzed 115 CBCT scans of 10 prostate patients. CT-to-CBCT registration was performed using (a) global RR, (b) bony RR, or (c) bony RR refined by a local prostate RR using the CT clinical target volume (CTV) expanded with 1-to-20-mm varying margins. After propagation of the manual CT contours, automatic CBCT contours were generated. For evaluation, a radiation oncologist manually delineated the CTV on the CBCT scans. The propagated and manual CBCT contours were compared using the Dice similarity and a measure based on the bidirectional local distance (BLD). We also conducted a blind visual assessment of the quality of the propagated segmentations. Moreover, we automatically quantified rectal distension between the CT and CBCT scans without using the manual CBCT contours and we investigated its correlation with the registration failures. To improve the registration quality, the air in the rectum was replaced with soft tissue using a filter. The results with and without filtering were compared. RESULTS: The statistical analysis of the Dice coefficients and the BLD values resulted in highly significant differences (p<10(-6)) for the 5-mm and 8-mm local RRs vs the global, bony and 1-mm local RRs. The 8-mm local RR provided the best compromise between accuracy and robustness (Dice median of 0.814 and 97% of success with filtering the air in the rectum). We observed that all failures were due to high rectal distension. Moreover, the visual assessment confirmed the superiority of the 8-mm local RR over the bony RR. CONCLUSION: The most successful CT-to-CBCT RR method proved to be the 8-mm local RR. We have shown the correlation between its registration failures and rectal distension. Furthermore, we have provided a simple (easily applicable in routine) and automatic method to quantify rectal distension and to predict registration failure using only the manual CT contours.