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11.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
12.
13.
We evaluated the genetic variation of Echinococcus G7 strain in larval and adult stages using a fragment of the mitochondrial cox1 gen. Viscera of pigs, bovines, and sheep and fecal samples of dogs were inspected for cystic and canine echinococcosis, respectively; only pigs had hydatid cysts. Bayesian inferences grouped the sequences in an E. canadensis G7 cluster, suggesting that, in Mexico, this strain might be mainly present. Additionally, the population genetic and network analysis showed that E. canadensis in Mexico is very diverse and has probably been introduced several times from different sources. Finally, a scarce genetic differentiation between G6 (camel strain) and G7 (pig strain) populations was identified.Echinococcus granulosus sensu lato (s.l.) includes species that cause cystic echinococcosis (CE), one of the most important and widespread parasitic zoonoses. Recent phylogenetic studies based on both mitochondrial and nuclear DNA genes show that E. granulosus s.l. consists of at least four valid species: E. granulosus sensu stricto (s.s.; genotypes G1–G3), E. equinus (G4), E. ortleppi (G5), and E. canadensis (G6–G10). Genotypes G6/G7 are closely related and referred to as camel and pig strains, respectively.13 The pig–dog cycle is mainly present in Mexico and maintains the G7 strain.4,5 Although there are isolated reports of E. oligarthrus in a wild cat,6 E. ortleppi (E. granulosus s.l.; G5) in a patient,7 and E. granulosus s.s. (G1) in a rural pig, there is no evidence that these species are maintained in Mexico.8 No data of CE caused by G7 have been documented in Mexican patients, although there is a high number of E. canadensis G7-infected patients in central Europe, pointing to the importance of this strain as a cause of human CE.9,10 There are only two genetic studies performed in samples from Mexico. Cruz-Reyes and others5 documented that G7 parasites of Mexican and Polish pig isolates showed similar patterns by restriction fragment length polymorphism (RFLP) of ribosomal DNA (rDNA) internal transcribed spacer 1 (ITS1) and random amplified polymorphic DNA (RAPD) techniques, and although polymerase chain reaction (PCR) -sequencing analysis of mitochondrial cox1 gen fragment was performed, no polymorphism data were reported. Sharma and others11 identified two variants (A and B) inside of the G6/G7 group consisting of samples from Mexico and Argentina using five nuclear markers (elongation factor 1α, transforming growth factor-β receptor kinase, thioredoxin peroxidase, calreticulin, and ezrin-radixin-moesin-like protein). Because some local slaughter records from northern Mexico indicate the presence of Echinococcus spp. in livestock animals,5 the objective of this study was to investigate if parasites in pigs and dogs correspond to G7 and if so, describe its genetic variation.Infected animals were identified in the municipal slaughterhouse of Calera, Zacatecas (north central Mexico), where farm and backyard livestock animals coming from the whole state and other surrounding states were included. For this purpose, viscera from 387 pigs, 243 bovines, and 32 sheep were inspected for the larval stage of Echinococcus. Nine pigs (six pigs from Zacatecas, two pigs from Aguascalientes, and one pig from Morelos) were found infected, and hydatid cysts were obtained under aseptic conditions. After cyst contents were aspirated and centrifuged, aliquots were examined under microscopy to confirm the presence of protoscolices, and pellets were kept in 70% ethanol at −20°C until DNA extraction. Each cyst from each animal was considered as an isolate.Based on the presence of the parasites previously identified in Calera''s slaughterhouse, a rural community located in the central area of Zacatecas at 22°55′ N, 102°48′ W was selected to look for the adult stage of this parasite. For this search, all dogs (60) present in the community were sampled one time for feces after obtaining verbal consent from the owner; samples were used to identify taeniid eggs by the Faust technique, antigens in stool samples (copro-antigens) by enzyme-linked immunosorbent assay (ELISA; CpAg ELISA), and DNA by Copro-PCR. The CpAg ELISA was performed as described by Allan and others12 and Moro and others.13 For Copro-PCR, only positive samples by CpAg ELISA were analyzed using JB3 and JB4 primers to amplify a cox1 gen fragment.14 Coprological analysis of dogs showed that 11 samples were positive by CpAg ELISA (18.3%); only 2 of these samples had taeniid tapeworms (3.4%), and 3 of 11 samples yielded products of approximately 450 bp. All amplicons obtained of hydatid cysts and fecal samples were purified, sequenced on both strands, submitted to GenBank (accession numbers KF734649-KF734660), and compared with several mitochondrial DNA sequences of cox1. Dogs positive for taeniid eggs or antigens were purged and treated with praziquantel at 30 mg/kg and arecoline bromide at 2 mg/kg. The protocol was previously approved by the Ethics and Research Committees of the General Hospital “Dr. Manuel Gea Gonzalez”; government and health authorities of the municipality and community also authorized our study.All sequences were subjected to the Basic Local Alignment Search Tool (BLAST) search in the GenBank database; multiple alignments were performed with the CLUSTAL W and MUSCLE programs,15,16 with manual adjusted in MEGA program v517 to determine the appropriate model of molecular evolution in the Modeltest 3.7 program.18 The phylogenetic reconstruction using Bayesian inference was performed with Mr Bayes 3.2.1 program.19 Unrooted haplotype networks were created using NETWORK 4.611 software and nested according to the rules in median-joining networks.20 An analysis of genetic diversity within and between populations was performed using DnaSPv421 and included nucleotide diversity (π), haplotype polymorphism (θ), genetic differentiation index (FST), and Tajima''s D test. Analysis of molecular variance (AMOVA) was used to examine the population genetic structure between populations by ΦST as the genetic fixation index (analogous to FST) obtained by ARLEQUIN software.22After multiple alignments, all sequences of larval and adult stages showed 98% or higher identity with E. canadensis, whereas the Bayesian phylogenetic tree and the haplotype network inference grouped these sequences in the E. canadensis G7 cluster. Sequences for cox1 of E. canadensis from Africa, Asia, Europe, Latin America, and North America deposited in the GenBank databases (N = 58) as well as our sequences (accession numbers KF734649-KF734660) were analyzed. The results for π and θ were 0.0118 and 0.718, and the result of Tajima''s D test was −2.1885 (P < 0.01). Genetic differentiation indexes between different paired sequences of E. canadensis genotypes are shown in
Population APopulation BFSTAMOVAReferences
ΦSTSSVCPercent
G6G70.0310.0851.6400.0608.53038
G6G80.8930.93737.7675.39593.7
G6G100.6240.61315.7980.72661.3
G7G80.7830.76027.2504.31576.030,31,39,40
G7G100.3590.3368.7220.53233.6
G8G100.8820.88140.0255.99188.130,34,36,39
Mexico (G7)Europe (G7)0.2010.1793.4940.25917.930,31,40,41
Latin America (G7)Europe (G7)0.1460.1132.4610.13811.3
Latin America (G7)Africa (G6)0.1470.1543.3340.17115.431,33,35
Latin America (G7)Asia (G6)0.1560.1262.7220.14412.630,31
Latin America (G7)Africa–Asia (G6)0.1510.2053.8330.18020.630,31,33,35
Europe (G7)Africa (G6)0.0470.0430.7270.0224.330,33,35,40,41
Europe (G7)Asia (G6)0.0610.0190.4720.0249.130,40,41
Europe (G7)Africa-Asia (G6)0.0420.0600.6500.2336.030,33,35,40,41
Open in a separate windowEurope (G7) includes G7 sequences from Italy, Poland, and Romania. Latin America (G7) includes G7 sequences from Mexico and Peru. Africa (G6) includes G6 sequences from Algeria, Ethiopia, Mauritania, and Sudan. Asia (G6) includes G6 sequences from Iran and Kazakhstan. Africa–Asia (G6) includes G6 sequences from China, Iran, Mauritania, Mongolia, and Russia. SS = sum of squared; VC = variance of components.For the network analysis, haplotypes of E. canadensis (G6, G7, G8, and G10), according to their hosts and country of origin, were included and exhibited three relevant dispersion centers (clustering more than nine haplotypes in each one of them): one for G10 from North America with elk/wolf, one for G6/G7 from Iran, Mauritania, and Peru with camel and sheep, and one for G6/G7 from Africa, Asia, and Latin America with cattle, camel, dog, elk, goat, and human. Interestingly, some G7 pig haplotypes from Mexico are displayed around the third dispersion center; in contrast, other G7 haplotypes from European and Asian countries are clustered around the second dispersion center (Figure 1).Open in a separate windowFigure 1.Haplotype network for E. canadensis using cox1 sequences of different countries and hosts. Numbers on branches refer to mutational changes. Sizes of circles are proportional to haplotype frequencies (numbers of haplotypes are shown inside circles). Thus, major circles represent ancestral haplotypes, and small circles represent missing haplotypes. Hosts are shown on a side of the haplotypes, and the three big ellipses with discontinuous lines containing G6/G7, G8, and G10.The sequences obtained from three dogs and nine infected pigs showed that E. canadensis (G7) was the only strain identified, indicating that it is the main genotype present in Mexico, which had been previously reported.4,5 This study also shows that E. canadensis (G6, G7, G8, and G10) is lightly more polymorphic than other species of the genus Echinococcus (π = 0.0118), and the negative value of Tajima''s D test suggests a recent expansion for the populations. Haag and others23 reported π = 0.0005 for E. multilocularis and π = 0.0090 for E. granulosus using mitochondrial (nad) and nuclear (ActII, Hbx2, and AgB) sequences; in addition, Sharma and others11 performed a population genetic analysis of E. granulosus s.s. using cox1 sequences and found that π ranged from 0.0039 to 0.0093 for E. granulosus s.s. isolates from India, and they also found a negative value for Tajima''s D test. Small sample sizes and lengths of the nucleotide sequences might affect the π values, showing a tendency toward underestimation.24 In addition, most studies of genetic variation in Echinococcus have used around a dozen sequences; therefore, π results might not be directly comparable among them. However, even under these considerations, this comparison allows us to highlight the genetic diversity among populations of E. canadensis. Furthermore, we found that, in E. canadensis populations, G6 and G7 have a scarce differentiation (FST and ΦST close to 0.1), whereas it is high for E. canadensis G8 and G10 (FST and ΦST > 0.6). In contrast, in a study focused on the genetic diversity of E. granulosus s.s., hydatid cysts from four European countries (Bulgaria, Hungary, Romania, and Italy) were evaluated by sequences of cox1 and showed FST values up 0.187.25 In this study, when G6 and G7 were divided in geographic areas, a similar genetic differentiation was observed with FST and ΦST < 0.1, except when Latin America (G7) was matched with Europe, Africa, or Asia (FST and ΦST = 0.15–0.2), suggesting that the former population reflects a great genetic differentiation regarding the latter populations. This is strengthened by the network analysis, in which some haplotypes of pigs from Mexico are clustered in different branches from those from pigs of European countries.Based on the network analysis, we might deduce the following inferences. (1) E. canadensis G7 in Mexico is very diverse and has probably been introduced from abroad several times from different sources (i.e., Figure 1 shows that six Mexican isolates have from 4 to 14 mutational changes between the isolate and the main haplotype). (2) Haplotypes grouped in the North American wildlife cluster (G10) are closer within them (with one or two mutational changes), and they are placed far away from Mexican isolates; thus, they might be ruled out as sources of introduction to Mexico. (3) Differentiation between G6 and G7 would not make any sense based on the differentiation of genetic indexes found for both genotypes (FST and ΦST close to 0.1). Additionally, one of the main ancestral dispersion centers in the network analysis clustered identical haplotypes of G6 and G7 from China, Mexico, Peru, Sudan, and Russia. The species status of E. canadensis is still controversial,13,5,25 because biologically different strains (G6–G10) have been unified. The camel (G6) and pig (G7) strains (both maintained primarily by dog-mediated domestic lifecycles from tropical to temperate zones) are ecologically and geographically segregated from G8 to G102,26; therefore, some works have suggested that G6 and G7 should be treated as a single species: E. intermedius.5,27 However, in recent taxonomic revisions, this proposal has been considered inappropriate,2,26 and the specific name of E. canadensis seems to be the most suitable for handling the closely related genotypes. Thompson and Lymbety28 have argued that knowledge of the genetic structure of cestodes can be applied to the epidemiology and the control of these parasites, because genetic variation within and between populations determines future evolutionary changes, genetic differentiation, and speciation. According to our results, it is probable that E. canadensis G7 has been accidentally introduced from abroad several times through different sources, except from North America (where G10 is more prevalent). This knowledge may have important implications for control of the zoonosis, mainly in areas that lack adequate veterinary control, which could prompt an important health problem. Although presently there are few cases of human cystic echinococcosis in Mexico, interestingly, a study performed in a rural community where an autochthonous human case of CE was detected in 2006 showed that, although some risk practices (such as feeding dogs with infected viscera) were observed, no data of CE in livestock and canine echinococcosis were found, suggesting that CE in Mexico has an unclear pattern.29  相似文献   
14.
Impact of Bispectral Index for monitoring propofol remifentanil anaesthesia. A randomised clinical trial     
P. BRESIL  M. S. NIELSSON  L. P. MALVER  K. KRÆMER  O. SCHJØRRING  C. DETHLEFSEN  P. H. LAMBERT 《Acta anaesthesiologica Scandinavica》2013,57(8):978-987
  相似文献   
15.
Refrigerated storage of lyophilized and rehydrated, lyophilized human red cells   总被引:6,自引:0,他引:6  
SO Sowemimo-Coker  ; RP Goodrich  ; CR Zerez  ; KR Tanaka 《Transfusion》1993,33(4):322-329
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods.  相似文献   
16.
Laparoscopic transthoracic liver resection     
Jaime Arthur Pirola KRüGER  Fabrício Ferreira COELHO  Marcos Vinícius PERINI  Paulo HERMAN 《Brazilian archives of digestive surgery》2014,27(4):288-290
  相似文献   
17.
PCR-positivity in harvested bone marrow predicts relapse after transplantation with autologous purged bone marrow in children in second remission of precursor B-cell acute leukaemia     
SUSAN F.  VERVOORDELDONK  PAULINE A.  MERLE  HENK  BEHRENDT  ERIC J.  STEENBERGEN  HENK  VAN DEN BERG  ELISABETH R.  VAN WERING  ALBERT E. G.  KR. VON DEM BORNE  C. ELLEN  VAN DER SCHOOT  ELEONORE F.  VAN LEEUWEN & INEKE C. M.  SLAPER-CORTENBACH 《British journal of haematology》1997,96(2):395-402
Purging of autologous bone marrow (BM) grafts of children in second remission after a relapse of precursor B acute lymphoblastic leukaemia (ALL) in the BM has been carried out in our laboratory since 1987, initially by complement mediated cell lysis. This protocol was extended by performing an immunorosette depletion before lysis with complement. The aim of the present study was to assess by polymerase chain reaction the presence of residual leukaemic cells in the BM grafts before and after purging. The results were then correlated to clinical outcome. In 24/28 patients a PCR product was obtained by amplification of IgH and/or TcR junctional regions. BM before purging was available for analysis in 13 patients. We found that leukaemic cells could be detected in 8/13 (62%) of these grafts before purging . All these eight patients experienced a relapse, regardless of whether the purging procedure had been successful (defined as achievement of PCR-negativity) or not. In contrast, none of the five patients with PCR-negative grafts before purging relapsed ( P  = 0.0008). One patient died due to transplant-related toxicity. Of the remaining 23 patients, nine patients received a PCR-positive BM graft after purging. All these nine patients experienced a relapse as compared to 6/14 whose BM was PCR-negative after purging ( P  = 0.0072). Two of eight PCR-positive BM grafts could be purged to PCR-negativity. Thus, improvements both in treatment of leukaemia and in purging efficacy are still needed.  相似文献   
18.
MR shoulder arthrography in patients younger than 40 years of age: Frequency of rotator cuff tear versus labroligamentous pathology     
KR Rowan  G Andrews  A Spielmann  J Leith 《Journal of Medical Imaging and Radiation Oncology》2007,51(3):257-259
The purpose of this study was to compare the frequency of rotator cuff pathology versus labroligamentous pathology in patients younger than 40 years and to determine whether routine MR arthrography is justified in all patients in this age group, regardless of the clinical symptoms. The MR arthrography was carried out on 332 patients 40 years of age and younger. Two hundred and forty‐three patients had clinical history of instability and possible labroligamentous pathology. Eighty‐nine patients had no history or physical signs of instability and were referred for reasons other than instability, such as assessment for rotator cuff tear. In the 243 patients younger than 40 years with clinical history of potential labral pathology, 39% (95/243) showed a labral tear and 2.1% (5/243) had a full‐thickness rotator cuff tendon tear. In the 89 patients with no history suggesting labral pathology, 19% (17/89) showed an unsuspected labral tear and 4.5% (4/89) had a full‐thickness rotator cuff tear. These findings suggest that, regardless of the clinical indication for referral, patients aged 40 and less referred for shoulder MRI should be imaged using MR arthrography because of the significant risk that symptoms are related to unsuspected labral pathology.  相似文献   
19.
Lecture 3: dynamic MR imaging of the female genitalia using AngioMARK: initial experience evaluating the female sexual response     
Deliganis AV  Maravilla KR  Heiman JR  Carter W  Weisskoff RM  Garland P  Echelard D  Hackbert L  Schmiedl UP 《International journal of impotence research》2000,12(Z3):S45
  相似文献   
20.
Computer graphics for digitally formatted images     
Templeton  AW; Johnson  JA; Anderson  WH; Cook  LT; Dwyer  SJ  d; Preston  DF; Lee  KR; Rosenthal  SJ; Batnitzky  S; Levine  E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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