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91.
Nathaniel H. Robin Beatrice Sellinger Donna McDonald-McGinn Elaine H. Zackai Beverly S. Emanuel Deborah A. Driscoll 《American journal of medical genetics. Part A》1995,56(1):94-96
Deletions of 22qll cause DiGeorge sequence (DGS), velo-cardio-facial syndrome (VCFS), conotruncal anomaly face syndrome, and some isolated conotruncal heart anomalies. Demonstration of a 22qll deletion in a patient with manifestations of DGS and Noonan syndrome (NS) has raised the question of whether NS is another of the chromosome 22 microdeletion syndromes. This prompted us to evaluate a cohort of patients with NS for evidence of 22qll deletions. Five of 6 NS propositi studied in our laboratory with marker N25 (D22S75) did not have a 22qll deletion. A 2-month-old infant with several findings suggestive of NS did have a 22qll deletion, suggesting that a small number of 22qll deletion propositi may present with a NS-like picture. However, most cases of NS must have another cause. © 1995 Wiley-Liss, Inc. 相似文献
92.
Endoscopic sclerotherapy as compared with endoscopic ligation for bleeding esophageal varices. 总被引:30,自引:0,他引:30
G V Stiegmann J S Goff P A Michaletz-Onody J Korula D Lieberman Z A Saeed R M Reveille J H Sun S R Lowenstein 《The New England journal of medicine》1992,326(23):1527-1532
BACKGROUND. Endoscopic sclerotherapy is an accepted treatment for bleeding esophageal varices, but it is associated with substantial local and systemic complications. Endoscopic ligation, a new form of endoscopic treatment for bleeding varices, may be safer. We compared the effectiveness and safety of the two techniques. METHODS. In this randomized trial we compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices. Sixty-five patients were treated with sclerotherapy, and 64 with ligation. Initial treatment for acute bleeding was followed by elective retreatment to eradicate varices. The patients were followed for a mean of 10 months, during which we determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival. RESULTS. Active bleeding at the first treatment was controlled by sclerotherapy in 10 of 13 patients (77 percent) and by ligation in 12 of 14 patients (86 percent). Slightly more sclerotherapy-treated patients had recurrent hemorrhage during the study (48 percent vs. 36 percent for the ligation-treated patients, P = 0.072). The eradication of varices required a lower mean (+/- SD) number of treatments with ligation (4 +/- 2 vs. 5 +/- 2, P = 0.056) than with sclerotherapy. The mortality rate was significantly higher in the sclerotherapy group (45 percent vs. 28 percent, P = 0.041), as was the rate of complications (22 percent vs. 2 percent, P less than 0.001). The complications of sclerotherapy were predominantly esophageal strictures, pneumonias, and other infections. CONCLUSIONS. Patients with cirrhosis who have bleeding esophageal varices have fewer treatment-related complications and better survival rates when they are treated by esophageal ligation than when they are treated by sclerotherapy. 相似文献
93.
Identification and disruption of the gene encoding the third member of the low-molecular-mass rhoptry complex in Plasmodium falciparum 下载免费PDF全文
The low-molecular-mass rhoptry complex of Plasmodium falciparum consists of three proteins, rhoptry-associated protein 1 (RAP1), RAP2, and RAP3. The genes encoding RAP1 and RAP2 are known; however, the RAP3 gene has not been identified. In this study we identify the RAP3 gene from the P. falciparum genome database and show that this protein is part of the low-molecular-mass rhoptry complex. Disruption of RAP3 demonstrated that it is not essential for merozoite invasion, probably because RAP2 can complement the loss of RAP3. RAP3 has homology with RAP2, and the genes are encoded on chromosome 5 in a head-to-tail fashion. Analysis of the genome databases has identified homologous genes in all Plasmodium spp., suggesting that this protein plays a role in merozoite invasion. The region surrounding the RAP3 homologue in the Plasmodium yoelii genome is syntenic with the same region in P. falciparum; however, there is a single gene. Phylogenetic comparison of the RAP2/3 protein family from Plasmodium spp. suggests that the RAP2/3 duplication occurred after divergence of these parasite species. 相似文献
94.
In vitro histamine release induced by radiocontrast media and various chemical analogs in reactor and control subjects 总被引:1,自引:0,他引:1
M C Rice P Lieberman R L Siegle J Mason 《The Journal of allergy and clinical immunology》1983,72(2):180-186
The factors governing in vitro basophil histamine release induced by radiocontrast material (RCM) were evaluated by the use of two RCMs (diatrizoate and metrizamide) and three structural analogs of RCM (benzoic acid, diaminobenzoic acid, and 3-acetamidobenzoic acid) in basophil histamine-release studies. Diatrizoate was chosen because it is a commonly used RCM and is routinely administered as a hypertonic drug (958 mOsm/kg or greater). Metrizamide is a newly synthesized RCM and is routinely administered in isotonic form (approximately 280 mOsm/kg). The analogs were used in hope of identifying any structure-function relationship that might exist between RCMs and the activation of a proposed basophil membrane receptor responsible for the induction of de granulation. In addition, results in a control group of normal subjects were compared with those in a group of patients who had experienced anaphylactoid reactions to intravenous RCM. Basophils from both groups were incubated with diatrizoate and metrizamide to assess their relative sensitivity to these drugs. Both metrizamide and diatrizoate induced in vitro histamine release. Therefore hypertonicity is not an absolute requirement for RCM-induced in vitro basophil de granulation. Although there was a trend far reagents without a prosthetic group at position 5 on the benzene ring (especially 3-acetamidobenzoic acid) to induce more release of histamine than reagents with such a prosthetic group, differences between these reagents did not reach statistical significance. Therefore no clearcut structure-function relationship could be demonstrated. “Reactor” subjects released significantly-larger percents of their intracellular histamine than did “nonreactors” (p < 0.05). Degranulated cells retained their ability to exclude trypan blue, an observation suggesting that RCM-induced histamine release does not involve cell death. 相似文献
95.
Chemiluminescent and flow cytometric analysis of gamma interferon preincubation on neonatal and adult rat polymorphonuclear leukocytes. 下载免费PDF全文
R R Wittler M M Lieberman D D Paine S L Muehlbauer J E Lima D M Sachanandani C A Pinney 《Clinical and Vaccine Immunology : CVI》1996,3(5):527-532
Gamma interferon (IFN-gamma) has multiple immunomodulating effects and has been postulated as a possible immunopotentiating agent for the prevention or treatment of neonatal infections. This report describes the effect of rat recombinant IFN-gamma on the oxidative burst activity and CD11b expression of neonatal and adult rat polymorphonuclear leukocytes (PMNL). Oxidative burst activity was assessed by chemiluminescence and dihydrorhodamine flow cytometry. Neonatal PMNL exhibited significantly less oxidative burst activity than did adult PMNL. IFN-gamma mildly enhanced the chemiluminescence response of PMNL from both the rat pups and adults, but this effect was not statistically significant when analyzed by a multivariate model of repeated-measures analysis of variance for both chemiluminescence and dihydrorhodamine flow cytometry. CD11b expression was also not significantly enhanced by IFN-gamma. 相似文献
96.
Mitogenic response of marmoset lymphocytes: cytokinetics and identification of responsive cells 下载免费PDF全文
Isotope (tritiated thymidine, [3H]Tdr) incorporation into lymphocytes from two marmoset species, New World primates which are haemopoietic chimeras, was studied using peripheral blood lymphocyte (PBL) cultures incubated in vitro for 1–5 days with different concentrations of Concanavalin A (Con A), leucoagglutinin (LA), bacterial lipopolysaccharide (LPS) from gram-negative bacteria, rabbit anti-marmoset immunoglobulin (anti-Ig) serum, thymosin or irradiated histoincompatible (xenogeneic) lymphocytes. Only the plant lectins and xenogeneic lymphoid cells stimulated the uptake of [3H]Tdr. Lymphocyte enrichment experiments demonstrated that cells responsive to plant lectins and xenoantigens were primarily thymus-derived (T) lymphocytes. Bacterial endotoxin (LPS), however, enhanced the mitogenic response of PBL to Con A when LPS and plant lectin were added together at culture initiation. Thymosin caused either enhancement or suppression of the response to Con A depending on its time of addition relative to lectin stimulation. Addition of thymosin to lymphocyte cultures with Con A or 24 h later caused a decrease in isotope incorporation, while addition of thymosin 48 h later caused a 12–100% increase in [3H]Tdr uptake. Lymphocyte chimerism did not influence the mitogenic response since single-born, nonchimeric marmosets responded to plant lectins in a manner similar to marmosets with varying proportions of chimeric blood elements. Cytological analysis of stimulated lymphocytes from heterosexual marmosets revealed the percentage chimerism in the polyclonal mitogenic response and the clonal mixed lymphocyte reaction to be similar. 相似文献
97.
Oligonucleotide Ligation Assay for Detecting Mutations in the Human Immunodeficiency Virus Type 1 pol Gene That Are Associated with Resistance to Zidovudine, Didanosine, and Lamivudine 总被引:3,自引:0,他引:3 下载免费PDF全文
Reva E. Edelstein Deborah A. Nickerson Vincent O. Tobe Laura A. Manns-Arcuino Lisa M. Frenkel 《Journal of clinical microbiology》1998,36(2):569-572
This report describes the detection of mutations in the pol gene of human immunodeficiency virus type 1 associated with resistance to zidovudine, didanosine, and lamivudine by genotyping by an oligonucleotide ligation assay specific codons in the pol gene amplified by PCR. Our studies demonstrate the sensitivity, simplicity, and specificity of this genotyping system. 相似文献
98.
Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women 总被引:4,自引:0,他引:4
Tworoger SS Yasui Y Vitiello MV Schwartz RS Ulrich CM Aiello EJ Irwin ML Bowen D Potter JD McTiernan A 《Sleep》2003,26(7):830-836
STUDY OBJECTIVES: To examine the effects of a moderate-intensity exercise or stretching intervention and changes in fitness, body mass index, or time spent outdoors on self-reported sleep quality and to examine the relationship between the amount and timing of exercise and sleep quality. DESIGN: A randomized intervention trial. SETTING: A cancer research center in Seattle, Washington. PARTICIPANTS: Postmenopausal, overweight or obese, sedentary women not taking hormone replacement therapy, aged 50 to 75 years, and recruited from the Seattle metropolitan area. INTERVENTIONS: A yearlong moderate-intensity exercise (n=87) and a low-intensity stretching (n=86) program. MEASUREMENTS AND RESULTS: Among morning exercisers, those who exercised at least 225 minutes per week had less trouble falling asleep (odds ratio [OR]: 0.3, P < or = .05) compared with those who exercised less than 180 minutes per week. However, among evening exercisers, those who exercised at least 225 minutes per week had more trouble falling asleep (OR: 3.3, P < or = .05) compared to those who exercised less than 180 minutes per week. Stretchers were less likely to use sleep medication (OR = 0.4, P < or = .05) and have trouble falling asleep (OR: 0.7, P < or = .10) during the intervention period compared with baseline. A greater than 10% versus a 1% or less increase in maximum O2 consumption over the year was associated with longer sleep duration (P < or = .05), less frequently falling asleep during quiet activities (P < or = .05), and less use of sleep medication (P < or = .05). Reductions in body mass index and increases in time spent outdoors had inconsistent effects on sleep quality. CONCLUSIONS: Both stretching and exercise interventions may improve sleep quality in sedentary, overweight, postmenopausal women. Increased fitness was associated with improvements in sleep. However, the effect of moderate-intensity exercise may depend on the amount of exercise and time of day it is performed. 相似文献
99.
Bedside to bench and back again: how animal models are guiding the development of new immunotherapies for cancer 总被引:3,自引:0,他引:3
Finkelstein SE Heimann DM Klebanoff CA Antony PA Gattinoni L Hinrichs CS Hwang LN Palmer DC Spiess PJ Surman DR Wrzesiniski C Yu Z Rosenberg SA Restifo NP 《Journal of leukocyte biology》2004,76(2):333-337
Immunotherapy using adoptive cell transfer is a promising approach that can result in the regression of bulky, invasive cancer in some patients. However, currently available therapies remain less successful than desired. To study the mechanisms of action and possible improvements in cell-transfer therapies, we use a murine model system with analogous components to the treatment of patients. T cell receptor transgenic CD8+ T cells (pmel-1) specifically recognizing the melanocyte differentiation antigen gp100 are adoptively transferred into lympho-depleted mice bearing large, established, 14-day subcutaneous B16 melanoma (0.5-1 cm in diameter) on the day of treatment. Adoptive cell transfer in combination with interleukin interleukin-2 or interleukin-15 cytokine administration and vaccination using an altered form of the target antigen, gp100, can result in the complete and durable regression of large tumor burdens. Complete responders frequently develop autoimmunity with vitiligo at the former tumor site that often spreads to involve the whole coat. These findings have important implications for the design of immunotherapy trials in humans. 相似文献
100.
Raymond E Biagini Barbara A MacKenzie Deborah L Sammons Jerome P Smith Edward F Krieg Shirley A Robertson Robert G Hamilton 《Annals of allergy, asthma & immunology》2006,97(2):196-202
BACKGROUND: In the absence of a US Food and Drug Administration (FDA)-cleared latex skin testing reagent, in vitro tests remain important for the diagnosis of latex allergy. OBJECTIVE: To evaluate the performance characteristics of IMMULITE 2000 3gAllergy (Immulite), a third-generation, FDA-cleared, continuous random-access immunoanalyzer, for the quantification of latex specific IgE. METHODS: Stored serum samples (N = 201) from patients classified as having positive or negative latex puncture skin test results were measured for latex specific IgE levels using Immulite, and these data were compared with historical results from 3 second-generation, FDA-cleared IgE antilatex assays (AlaSTAT [Ala], AutoCAP [CAP], and HY*TEC enzyme immunoassay [HT]). RESULTS: The diagnostic performances of the CAP, Ala, and Immulite assays (> or = 0.35 kU/L cutoff value) were equivalent in sensitivity and specificity (P > .05). The HT assay (> or = 0.05 kU/L cutoff value) was more sensitive and less specific (P < .05). Immulite (> or = 0.10 kU/L cutoff value) had greater sensitivity than Ala and CAP and greater specificity than HT (P < .05 for both). Diagnostic efficiency was greater for Immulite than for CAP, Ala, and HT (P < .05). CONCLUSIONS: The Immulite system is superior in diagnostic performance, especially at the 0.10 kU/L or greater cutoff level, for the diagnosis of latex allergy compared with older, second-generation assays. Immulite still misclassifies 15.5% of puncture skin test-positive individuals as negative for latex specific IgE. Compared with second-generation assays, Immulite represents a technological advance, with enhanced speed and less operator intervention. 相似文献