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1.
Myosin isozymes in avian skeletal muscles. I. Sequential expression of myosin isozymes in developing chicken pectoralis muscles 总被引:11,自引:0,他引:11
Susan Lowey Pamela A. Benfield Denise D. LeBlanc Guillermina S. Waller 《Journal of muscle research and cell motility》1983,4(6):695-716
Myosin has been purified from chicken pectoralis muscle at various stages of development, from 10 days' incubation to approximately 10 months after hatching. Embryonic myosin from the earliest stage showed a high level of ATPase activity, similar to that obtained for adult pectoralis myosin. Two-dimensional peptide mapping of partial chymotryptic digests showed, however, that is heavy chain is quite different from that of adult fast myosin. The immunological crossreactivity observed between embryonic myosin and adult fast (pectoralis) myosin is therefore due to shared antigenic determinants rather than the presence of any adult isoforms. In an accompanying paper we will show that embryonic myosin at 10 days' incubation is not a single species, but consists of at least two heavy chain isozymes. The minor fraction binds slow light chains preferentially, and appears to be largely responsible for the observed crossreactivity with slow (ALD) myosin. None of the embryonic myosins is equivalent to the adult forms. Prior to hatching, LC3f is present only in very small amounts (less than 5%), and the adult light chain pattern, containing LC1f and LC3f in equimolar amounts, is not generated until after one week post-hatching. At about that time a new heavy chain population is detected, different from either the embryonic heavy chain or the adult heavy chain. The adult heavy chain peptide pattern appears from about three weeks' post-hatching, but a map indistinguishable from that of adult myosin is not observed until about 26 weeks. None of the observed differences in peptide maps can be related to different strains of chicken; pectoralis myosin from adult White Rock gave an identical map to that from White Leghorn. Unexpectedly, posterior latissimus dorsi (PLD) myosin from White Leghorn appears to be different from pectoralis myosin from the same strain, despite the histochemical and immunocytochemical similarity of the two muscles. We conclude that myosin polymorphism is widespread in muscle tissue, and that the expression of myosin isozymes and their subunits is under developmental regulation. 相似文献
2.
A. Isla F. Alvarez M. Gutiérrez C. Gamallo M. García-Blázquez A. Vega 《Neuroradiology》1996,38(3):211-213
Primary lymphomas of the cranial vault are rare; only six patients have been described in the literature. We report a 75-year-old woman who was admitted to our hospital after a focal seizure. CT showed a homogeneous mass which, on contrast enhancement, was similar to a meningioma. The tumour was excised and found to be a centroblastic, centrocytic non-Hodgkin's lymphoma. Treatment was completed with radiotherapy and chemotherapy. 相似文献
3.
V Alberola C Camps M Provencio D Isla R Rosell C Vadell I Bover A Ruiz-Casado P Azagra U Jiménez J L González-Larriba P Diz F Cardenal A Artal A Carrato S Morales J J Sanchez R de las Pe?as E Felip G López-Vivanco 《Journal of clinical oncology》2003,21(17):3207-3213
PURPOSE: To compare the survival benefit obtained with cisplatin plus gemcitabine, a cisplatin-based triplet, and nonplatinum sequential doublets in advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Stage IIIB to IV NSCLC patients were randomly assigned to receive cisplatin 100 mg/m2 day 1 plus gemcitabine 1,250 mg/m2 days 1 and 8, every 3 weeks for six cycles (CG); cisplatin 100 mg/m2 day 1 plus gemcitabine 1,000 mg/m2 and vinorelbine 25 mg/m2 days 1 and 8, every 3 weeks for six cycles (CGV); or gemcitabine 1,000 mg/m2 plus vinorelbine 30 mg/m2 days 1 and 8, every 3 weeks for three cycles, followed by vinorelbine 30 mg/m2 days 1 and 8 plus ifosfamide 3 g/m2 day 1, every 3 weeks for three cycles (GV-VI). RESULTS: Five hundred fifty-seven patients were assigned to treatment (182 CG, 188 CGV, 187 GV-VI). Response rates were significantly inferior for the nonplatinum sequential doublet (CG, 42%; CGV, 41%; GV-VI, 27%; CG v GV-VI, P =.003). No differences in median survival or time to progression were observed. Toxicity was higher for the triplet: grade 3 to 4 neutropenia (GC, 32%; CGV, 57%; GV-VI, 27%; P <.05); neutropenic fever (CG, 4%; CGV, 19%; GV-VI, 5%; P <.0001); grade 3 to 4 thrombocytopenia (CG, 19%; CGV, 23%; GV-VI, 3%; P =.0001); and grade 3 to 4 emesis (GC, 22%; GCV, 32%; GV-VI, 6%; P <.0001). CONCLUSION: On the basis of these results, CG remains a standard regimen for first-line treatment of advanced NSCLC. 相似文献
4.
Análisis y minimización del riesgo de rotura de stock aplicado a la gestión en farmacia hospitalaria
José María Maestre Torreblanca Beatriz Isla Tejera María Isabel Fernández García José Ramón del Prado Llergo Teodoro Álamo Cantarero Eduardo Fernández Camacho 《Farmacia hospitalaria》2012,36(3):130-134
ObjectiveTo determine how many dispensary drugs should be in the safety stock in a tertiary hospital in accordance with the risk level and the number of days that the hospital is able to withstand a stockout.MethodsWe statistically analysed the infliximab order recorded over a period of 120 days. This drug is relevant for this study as it is costly and is immediately supplied to the clinic. Using the data records for purchasing and dispensing in our department, we created a table to compare the level of risk assumed with the number of units in stock and the number of days that the safety stock should last. In addition, we calculated how much stock there should be in accordance with different heuristic rules used by pharmacy departments.ResultsIn the period being studied, the daily order was 11.4 ± 14.8 units of infliximab. Using the methodology proposed, we discovered that there should be 79 units in the safety stock. Other hospital rules determine values of 47 and 119 units.ConclusionsThe method proposed allows us to discover the risk level that is assumed when selecting the safety stock. Therefore, we are able to design a safety stock policy consistent with the risk level adopted. Under certain assumptions the safety stock quota provided by this method could be reduced. Lastly, there is a notable difference between the safety stock values suggested by different rules, as it has been shown in this article. 相似文献
5.
6.
Reversible anergy of sIgM-mediated signaling in the two subsets of CLL defined by VH-gene mutational status 下载免费PDF全文
The 2 subsets of chronic lymphocytic leukemia (CLL), of worse or better prognosis, likely derive from pre-GC unmutated B cells, or post-GC mutated B cells, respectively. Different clinical behavior could relate to the ability of tumor cells to respond to surface (sIg)-mediated signals. Unmutated cases (U-CLL) have an increased ability to phosphorylate p72(Syk) in response to sIgM ligation compared to mutated cases (M-CLL). We now confirm and further investigate this differential signaling in a large cohort by [Ca(2+)](i) mobilization. Cases responding to sIgM ligation express higher levels of CD38, ZAP-70, and sIgM. However, CD38 does not influence signaling in vitro or associate with response in bimodal CD38-expressing cases. Similarly, ZAP-70 expression is not required for response in either U-CLL or M-CLL. Strikingly, partially or completely anergized sIgM responses from each subset can recover both sIgM expression and signal capacity spontaneously in vitro or following capping/endocytosis. This provides direct evidence for engagement of putative antigen in vivo. Signaling via sIgD differs markedly being almost universally positive in both U-CLL and M-CLL, with no association with CD38 or ZAP-70 expression. Downstream signaling pathways, therefore, appear intact in CLL, locating anergy to sIgM, mainly in M-CLL. Integration of differential isotype-specific effects mediated by (auto)antigen may determine tumor behavior. 相似文献
7.
8.
In the United States, between 1 and 3% of women suffer recurrent miscarriages; 50-70% of all conceptions fail. [1,2] Although in the majority of affected women the cause of recurrent miscarriages is unknown, an immune mechanism involving the inappropriate and subsequently injurious recognition of the conceptus by the mother's immune system has been proposed. Murine models have recently been developed that are relevant to this issue. We and others have identified a novel role for complement as an early effector in the pathway leading to pregnancy loss associated with placental inflammation. Indeed, it appears that inhibition of complement activation is an absolute requirement for normal pregnancy, and that in the antiphosphospholid syndrome overwhelming activation of complement triggered by antibodies (Ab) deposited in placenta leads to fetal injury. Identification of complement activation as a mediator of pregnancy loss and definition of the complement components necessary to trigger such injury is likely to lead to a better understanding of its pathogenesis and to new and improved treatments. 相似文献
9.
Moreno R Zamorano JL Serra V Almería C Rodrigo JL Herrera D Pérez de Isla L Mataix L Aubele A de Marco E Sánchez-Harguindey L Macaya C 《International journal of cardiology》2003,92(2-3):187-191
BACKGROUND: The effect of beta-radiation on extra-stent vascular remodeling in patients with in-stent restenosis has not been studied. The correlation between the extent of extra-stent plaque proliferation and that of intimal hyperplasia (IH) in in-stent restenosis in patients who received beta-radiation therapy as well as conventional therapy has also not been studied. METHODS: We evaluated the extra-stent remodeling in diffuse in-stent restenosis between a beta-radiation therapy patient group (188Re-MAG3, n=50) and a control group (n=9) by applying serial intravascular ultrasound (IVUS) analysis. Matching (post-intervention and follow-up) images were acquired at the follow-up lesion site and were available in 44 of 50 patients who received radiation therapy and in seven of nine control patients. RESULTS: There was a significant increase of the external elastic membrane (EEM) area in both groups: 16.4 +/- 3.3 mm2 post-intervention to 17.1 +/- 3.3 mm2 at follow-up, P=0.001 in the radiation therapy group, and 16.8 +/- 4.0 mm2 post-intervention to 17.4 +/- 4.1 mm2 at follow-up, P=0.008 in the control group. There were no statistically significant differences of the Delta EEM area between the two groups: 0.7 +/- 0.4 mm2 in the radiation therapy group vs. 0.6 +/- 0.4 mm2 in the control group, P=0.389. The Delta IH area correlated with the Delta EEM area in the control group (r=0.826, P=0.022), but not in the radiation therapy group (r=0.016, P=0.919). CONCLUSIONS: The findings of this IVUS study were that positive remodeling (increased EEM area) occurred equally in both control and irradiated patients with in-stent restenosis. The extent of remodeling was directly in proportion to IH in the control group, but no such relationship existed in the irradiated patient group. 相似文献
10.
Ulises Rodriguez-Prado Diego Emiliano Jimenez-Gonzalez Guillermina Avila Armando E. Gonzalez Williams Arony Martinez-Flores Carmen Mondragon de la Pe?a Rigoberto Hernandez-Castro Mirza Romero-Valdovinos Ana Flisser Fernando Martinez-Hernandez Pablo Maravilla Jose Juan Martinez-Maya 《The American journal of tropical medicine and hygiene》2014,91(6):1149-1153
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.1–3 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 ), 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, KF734649-KF73466015,16 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 ) 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 KF734649-KF734660Population A Population B FST AMOVA References ΦST SS VC Percent G6 G7 0.031 0.085 1.640 0.060 8.5 30–38 G6 G8 0.893 0.937 37.767 5.395 93.7 G6 G10 0.624 0.613 15.798 0.726 61.3 G7 G8 0.783 0.760 27.250 4.315 76.0 30,31,39,40 G7 G10 0.359 0.336 8.722 0.532 33.6 G8 G10 0.882 0.881 40.025 5.991 88.1 30,34,36,39 Mexico (G7) Europe (G7) 0.201 0.179 3.494 0.259 17.9 30,31,40,41 Latin America (G7) Europe (G7) 0.146 0.113 2.461 0.138 11.3 Latin America (G7) Africa (G6) 0.147 0.154 3.334 0.171 15.4 31,33,35 Latin America (G7) Asia (G6) 0.156 0.126 2.722 0.144 12.6 30,31 Latin America (G7) Africa–Asia (G6) 0.151 0.205 3.833 0.180 20.6 30,31,33,35 Europe (G7) Africa (G6) 0.047 0.043 0.727 0.022 4.3 30,33,35,40,41 Europe (G7) Asia (G6) 0.061 0.019 0.472 0.024 9.1 30,40,41 Europe (G7) Africa-Asia (G6) 0.042 0.060 0.650 0.233 6.0 30,33,35,40,41