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51.
Correlation of P-glycoprotein expression and function in childhood acute leukemia: a children's cancer group study 总被引:7,自引:0,他引:7
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents. 相似文献
52.
Shingleton BJ Rosenberg RB Teixeira R O'Donoghue MW 《Journal of cataract and refractive surgery》2007,33(11):1953-1957
PURPOSE: To determine the incidence of hypotony and intraocular pressure (IOP) elevation in the immediate and early postoperative period after temporal posterior limbal phacoemulsification and intraocular lens (IOL) implantation. SETTING: Ambulatory surgical center. METHODS: This prospective analysis comprised 310 eyes that had temporal posterior limbal phacoemulsification with IOL implantation. Surgical parameters included keratome incision of 2.85 mm, incision length of 2.5 mm, peribulbar anesthesia, case-completion IOP of 20 mm Hg, and postoperative lid taping. The IOP measurements were collected preoperatively and 30 minutes and 1 day after surgery. RESULTS: Nineteen eyes (6.1%) had an IOP lower than 5 mm Hg 30 minutes postoperatively in the absence of incision leakage at the paracentesis or keratome sites. Eighteen of the 19 eyes with postoperative hypotony received hydroxypropyl methylcellulose 2% (OcuCoat) and 1 received hypromellose 2% (Cellugel). None of the 23 eyes with an acrylic IOL implanted via a cylindrical lens inserter had an IOP lower than 5 mm Hg postoperatively. Suturing did not significantly affect the incidence of hypotony, and there were no postoperative complications related to hypotony. The mean IOP at 30 minutes was lower than at 1 day in the normal, glaucoma, and glaucoma-suspect groups. Twenty-one normal eyes (8.1%), 5 glaucoma eyes (15.6%), and 1 glaucoma-suspect eye (5%) had an IOP greater than 30 mm Hg 1 day postoperatively. CONCLUSIONS: Postoperative hypotony (IOP <5 mm Hg) occurred in 19 (6.1%) of 310 eyes. At 1 day, IOP higher than 30 mm Hg was more frequent in glaucoma eyes than in normal eyes. Although there were no direct problems related to hypotony at 30 minutes or to elevated IOP (>30 mm Hg) at 1 day, surgeons should be aware of and check for IOP variability (low and high) that can occur in normal, glaucoma, and glaucoma-suspect eyes within the first 24 hours after surgery. 相似文献
53.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献
54.
55.
Excel97在药物分析中的应用 总被引:1,自引:0,他引:1
目的:在药物分析中,电子表格软件MicrosoftExce197for Windows。方法:利用Excel的数据处理功能,进行药物的图表绘制、数据计算和统计处理,回归分析,特别是计算分析,并可建立分析数据库。结果和结论:Excel操作简单,功能强大,数据分析工作直观。 相似文献
56.
C.A.P.F. Alves U. Lbel J.S. Martin-Saavedra S. Toescu M.H. Tsunemi S.R. Teixeira K. Mankad D. Hargrave T.S. Jacques C. da Costa Leite F.G. Gonalves A. Vossough F. D'Arco 《AJNR. American journal of neuroradiology》2021,42(5):961
BACKGROUND AND PURPOSE:Primary posterior fossa tumors comprise a large group of neoplasias with variable aggressiveness and short and long-term outcomes. This study aimed to validate the clinical usefulness of a radiologic decision flow chart based on previously published neuroradiologic knowledge for the diagnosis of posterior fossa tumors in children.MATERIALS AND METHODS:A retrospective study was conducted (from January 2013 to October 2019) at 2 pediatric referral centers, Children''s Hospital of Philadelphia, United States, and Great Ormond Street Hospital, United Kingdom. Inclusion criteria were younger than 18 years of age and histologically and molecularly confirmed posterior fossa tumors. Subjects with no available preoperative MR imaging and tumors located primarily in the brain stem were excluded. Imaging characteristics of the tumors were evaluated following a predesigned, step-by-step flow chart. Agreement between readers was tested with the Cohen κ, and each diagnosis was analyzed for accuracy.RESULTS:A total of 148 cases were included, with a median age of 3.4 years (interquartile range, 2.1–6.1 years), and a male/female ratio of 1.24. The predesigned flow chart facilitated identification of pilocytic astrocytoma, ependymoma, and medulloblastoma sonic hedgehog tumors with high sensitivity and specificity. On the basis of the results, the flow chart was adjusted so that it would also be able to better discriminate atypical teratoid/rhabdoid tumors and medulloblastoma groups 3 or 4 (sensitivity = 75%–79%; specificity = 92%–99%). Moreover, our adjusted flow chart was useful in ruling out ependymoma, pilocytic astrocytomas, and medulloblastoma sonic hedgehog tumors.CONCLUSIONS:The modified flow chart offers a structured tool to aid in the adjunct diagnosis of pediatric posterior fossa tumors. Our results also establish a useful starting point for prospective clinical studies and for the development of automated algorithms, which may provide precise and adequate diagnostic tools for these tumors in clinical practice.In the past 10 years, there has been an exponential increase in knowledge of the molecular characteristics of pediatric brain tumors, which was only partially incorporated in the 2016 World Health Organization Classification of Tumors of the Central Nervous System.1 The main update in the 2016 Classification was the introduction of the molecular profile of a tumor as an important factor for predicting different biologic behaviors of entities which, on histology, look very similar or even indistinguishable.2 A typical example is the 4 main groups of medulloblastoma: wingless (WNT), sonic hedgehog (SHH) with or without the p53 mutation, group 3, and group 4. Although they may appear similar on microscopy, these categories have distinct molecular profiles, epidemiology, prognosis, and embryologic origin.3Subsequent to the publication of the 2016 World Health Organization Classification, further studies have identified even more molecular subgroups of medulloblastoma with possible prognostic implications4 and also at least 3 new molecular subgroups of atypical teratoid/rhabdoid tumor (AT/RT)5 and several subgroups of ependymoma.6 MR imaging shows promise as a technique for differentiating histologic tumors and their molecular subgroups. This capability relies on not only various imaging characteristics but also the location and spatial extension of the tumor, evident on MR imaging, which can be traced to the embryologic origin of the neoplastic cells.5,7-10One approach to the challenge of identifying imaging characteristics of different tumors in children is to use artificial intelligence. Yet despite this exciting innovation, correctly identifying the location of the mass and its possible use as an element for differential diagnosis still requires the expertise of an experienced radiologist. Previously, D''Arco et al11 proposed a flow chart (Fig 1) for the differential diagnosis of posterior fossa tumors in children based on epidemiologic, imaging signal, and location characteristics of the neoplasm. The aims of the current study were the following: 1) to validate, in a retrospective, large cohort of posterior fossa tumors from 2 separate pediatric tertiary centers, the diagnostic accuracy of that flow chart, which visually represents the neuroadiologist''s mental process in making a diagnosis of posterior fossa tumors in children, 2) to describe particular types of posterior fossa lesions that are not correctly diagnosed by the initial flow chart, and 3) to provide an improved, clinically accessible flow chart based on the results.Open in a separate windowFIG 1.Predesigned radiologic flow chart created according to the literature before diagnostic accuracy analysis. The asterisk indicates brain stem tumors excluded from the analysis. Double asterisks indicate relative to gray matter. Modified with permission from D''Arco et al.11 相似文献
57.
Lazzarini LC de Fatima do Amparo Teixeira M Souza Rodrigues R Marcos Nunes Valiante P 《Respiration; international review of thoracic diseases》2008,76(3):356-360
Necrotizing sarcoid granulomatosis (NSG) is a rare entity mainly characterized by a prominent granulomatous vasculitis affecting middle-aged or old individuals and with a favorable prognosis. Although many believe it is a variant of sarcoidosis, the proper classification is still a matter of debate as some of its features are found in sarcoidosis but also in Churg-Strauss syndrome, Wegener's disease and hypersensitivity pneumonitis. In this paper, we described for the first time a case of NSG in a family with several cases of sarcoidosis, reinforcing the relationship between NSG and sarcoidosis. Additional interesting findings were the young age of the patient (15 years old), the symptoms limited to the respiratory tract (uncommon when NSG affects youngsters) and the increase in serologic markers of autoimmune disease. Though complete criteria for autoimmune disease were not present, systemic lupus erythematosus and Sjogren's syndrome are possible candidates. As sarcoidosis is described to be associated with several autoimmune diseases, this finding is an additional suggestion of the relationship between both entities. 相似文献
58.
José Wellington Alves dos Santos Fabiani Palagi Machado Felipe Schaich Douglas Zaione Nascimento Tiago Teixeira Simon Luis Fernando Cibin Keli Cristina Mann Vinícius André Guerra Mateus Correa Marcos Ferreira Gazzoni Marta Pires da Rocha Melissa Daubermann Falster Ronaldo Manfredini Vassoler 《Respiratory Medicine Extra》2007,3(4):186-188
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60.
Izabela Guimar?es Barbosa Natália Pessoa Rocha Frankcinéia Assis érica Leandro Marciano Vieira Jair C Soares Moises Evandro Bauer Ant?nio Lúcio Teixeira 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(1)