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991.
One-stop clinic for assessment of risk for trisomy 21 at 11-14 weeks: a prospective study of 15 030 pregnancies. 总被引:4,自引:0,他引:4
R Bindra V Heath A Liao K Spencer K H Nicolaides 《Ultrasound in obstetrics & gynecology》2002,20(3):219-225
OBJECTIVE: To evaluate the performance of a one-stop clinic for assessment of risk (OSCAR) for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation. METHOD: Screening for trisomy 21 was carried out by OSCAR in 15 030 singleton pregnancies with live fetuses at 11-14 weeks. The estimated risk for trisomy 21 was calculated, and the women were counseled regarding this risk and the option of invasive testing or expectant management. Follow-up of the outcome of all pregnancies was carried out. The detection and false-positive rates for different risk cut-offs were calculated. RESULTS: Fetal NT and maternal serum free beta-hCG and PAPP-A were successfully measured in all cases. Pregnancy outcome, including karyotype results or the birth of a phenotypically normal baby, was obtained from 14 383 cases. The median maternal age of these cases was 34 (range 15-49) years and in 6768 (47.1%) the age was 35 years or greater. The median gestation at screening was 12 (range 11-14) weeks and the median fetal crown-rump length was 64 (range 45-84) mm. The estimated risk for trisomy 21 based on maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A was 1 in 300 or greater in 6.8% (967 of 14 240) normal pregnancies, in 91.5% (75 of 82) of those with trisomy 21 and in 88.5% (54 of 61) of those with other chromosomal defects. For a fixed false-positive rate of 5% the respective detection rates of screening for trisomy 21 by maternal age alone, maternal age and serum free beta-hCG and PAPP-A, maternal age and fetal NT, and by maternal age, fetal NT and maternal serum biochemistry were 30.5%, 59.8%, 79.3% and 90.2%, respectively. CONCLUSION: Screening for trisomy 21 by a combination of maternal age, fetal NT and maternal serum biochemistry at 11-14 weeks can be provided in an OSCAR setting and is associated with a detection rate of about 90% for a false-positive rate of 5%. 相似文献
992.
Brooks TD Slomp J Quax PH De Bart AC Spencer MT Verheijen JH Charlton PA 《Clinical & experimental metastasis》2000,18(6):445-453
Recent reports suggest that elevated levels of plasminogen activator inhibitor-1 (PAI-1) may contribute to tumour progression.
The studies reported here were designed to help elucidate PAI-1's contribution to the invasive and migratory phenotype. Antibodies
to PAI-1 dose-dependently, and significantly, inhibited the invasive and migratory potential of human HT1080 fibrosarcoma
cells, as did an antibody to uPA and the plasmin inhibitor aprotinin. Invasion of the human melanoma cell line, BLM, was also
attenuated by the anti-PAI-1 monoclonal antibody MAI-12. The non-invasive human melanoma cell line, IF6, which does not express
uPA, provided further confirmation of PAI-1 and uPA's role as, upon transfection with uPA, this cell line attained an invasive
phenotype, which was again attenuated by MAI- 12. Although antibodies to PAI-1 did not affect the adhesion of HT1080 cells
to vitronectin, the antibody to uPA reduced their attachment. Addition of exogenous PAI-1, however, prevented HT1080 cell
adhesion (IC50 180nM) and promoted cell detachment from vitronectin. Furthermore melanoma cells transfected with a uPA variant, which had
an impaired interaction with PAI-1, were not invasive and had impaired binding to vitronectin. These data highlight the importance
of a balanced proteolysis and suggest an additional role for PAI-1 distinct from its role in proteolysis. These data also
suggest that uPA and PAI-1 may co-operate in the migratory process by respectively facilitating the attachment to, and subsequent
detachment from, vitronectin in the extracellular matrix. These results support the clinical findings and indicate that modulation
of PAI-1 activity may be of therapeutic benefit for the treatment of cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
993.
Dr. D. P. Girvan MCISc FRCS J. Hansky MB FRACP J. Spencer MB FRCS J. H. Baron DM FRCP 《Digestive diseases and sciences》1974,19(11):977-986
The intravenous infusion of insulin 0.04 U/kg-hr for 2-1/2 hours was performed in 26 patients with chronic duodenal ulcer. In 15 patients this infusion test was compared with the standard test of a single intravenous injection of insulin 0.2 U/kg. The mean lowest blood glucose level in the infusion group (25.1 mg/100 ml) was significantly higher than in the standard test (17.4 mg/100 ml), and the interval from injection to acid stimulation about twice as long (75versus 45 minutes). The peak acid output and mean rise in acidity were comparable in the two procedures. Serum gastrin responded reciprocally to insulin-induced hypoglycemia with a significant inverse correlation between blood glucose and gastrin. In 13 patients tested after vagotomy, there was no significant difference in the rise in acidities in the two groups, and the Hollander status was the same in all but one patient. The mean basal, peak, and absolute rise of serum gastrin in unoperated patients and patients with incomplete vagotomy were almost identical. In patients with complete vagotomy there was no significant rise in serum gastrin after insulin infusion. Unpleasant side effects as assessed by an independent observer were fewer and less severe in patients undergoing infusion tests than in the standard test. The insulin infusion test is recommended as a safer and more acceptable test than the standard insulin test since it avoids severe hypoglycemia and has milder side effects yet achieves comparable acidity and acid outputs. Measurements of serum gastrin after either insulin test provide no additional information helpful in the assessment of the completeness of vagotomy. 相似文献
994.
Russell SM Elliott R Forshaw D Kelly PJ Golfinos JG 《中国神经肿瘤杂志》2005,3(4):295-295
OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance. 相似文献
995.
PURPOSE OF REVIEW: Recent advances in epilepsy surgery have developed a resurgence of interest in the use of surgical techniques for the treatment of intractable epilepsy. RECENT FINDINGS: More invasive procedures such as hemispherectomy and multiple subpial transection have become more popular. Disconnective techniques such as multiple subpial transection have provided a surgical option for patients whose epileptogenic zone resides in the eloquent cortex. Alternatively, new minimally invasive neurostimulation therapies have been introduced to preserve maximal cerebral tissue. Radiosurgery has been recently utilized in the treatment of epilepsy with preliminary promising results. SUMMARY: In this analysis, the authors will attempt to review the more recent surgical approaches and their indications for the treatment of medically intractable epilepsy. For patients with the epileptogenic zone in the noneloquent cortex, seizure focus resection remains the most reasonable approach to therapy. 相似文献
996.
Rogers KL Stinnakre J Agulhon C Jublot D Shorte SL Kremer EJ Brûlet P 《The European journal of neuroscience》2005,21(3):597-610
Measurements of local Ca2+ signalling at different developmental stages and/or in specific cell types is important for understanding aspects of brain functioning. The use of light excitation in fluorescence imaging can cause phototoxicity, photobleaching and auto-fluorescence. In contrast, bioluminescence does not require the input of radiative energy and can therefore be measured over long periods, with very high temporal resolution. Aequorin is a genetically encoded Ca(2+)-sensitive bioluminescent protein, however, its low quantum yield prevents dynamic measurements of Ca2+ responses in single cells. To overcome this limitation, we recently reported the bi-functional Ca2+ reporter gene, GFP-aequorin (GA), which was developed specifically to improve the light output and stability of aequorin chimeras [V. Baubet, et al., (2000) PNAS, 97, 7260-7265]. In the current study, we have genetically targeted GA to different microdomains important in synaptic transmission, including to the mitochondrial matrix, endoplasmic reticulum, synaptic vesicles and to the postsynaptic density. We demonstrate that these reporters enable 'real-time' measurements of subcellular Ca2+ changes in single mammalian neurons using bioluminescence. The high signal-to-noise ratio of these reporters is also important in that it affords the visualization of Ca2+ dynamics in cell-cell communication in neuronal cultures and tissue slices. Further, we demonstrate the utility of this approach in ex-vivo preparations of mammalian retina, a paradigm in which external light input should be controlled. This represents a novel molecular imaging approach for non-invasive monitoring of local Ca2+ dynamics and cellular communication in tissue or whole animal studies. 相似文献
997.
The relationship between knowledge of recent HbA1c values and diabetes care understanding and self-management 总被引:3,自引:0,他引:3
OBJECTIVE: Knowledge of one's actual and target health outcomes (such as HbA(1c) values) is hypothesized to be a prerequisite for effective patient involvement in managing chronic diseases such as diabetes. We examined 1) the frequency and correlates of knowing one's most recent HbA(1c) test result and 2) whether knowing one's HbA(1c) value is associated with a more accurate assessment of diabetes control and better diabetes self-care understanding, self-efficacy, and behaviors related to glycemic control. RESEARCH DESIGN AND METHODS: We conducted a cross-sectional survey of a sample of 686 U.S. adults with type 2 diabetes in five health systems who had HbA(1c) checked in the previous 6 months. Independent variables included patient characteristics, health care provider communication, and health system type. We examined bivariate and multivariate associations between each variable and the respondents' knowledge of their last HbA(1c) values and assessed whether knowledge of HbA(1c) was associated with key diabetes care attitudes and behaviors. RESULTS: Of the respondents, 66% reported that they did not know their last HbA(1c) value and only 25% accurately reported that value. In multivariate analyses, more years of formal education and high evaluations of provider thoroughness of communication were independently associated with HbA(1c) knowledge. Respondents who knew their last HbA(1c) value had higher odds of accurately assessing their diabetes control (adjusted odds ratio 1.59, 95% CI 1.05-2.42) and better reported understanding of their diabetes care (P < 0.001). HbA(1c) knowledge was not associated with respondents' diabetes care self-efficacy or reported self-management behaviors. CONCLUSIONS: Respondents who knew their HbA(1c) values reported better diabetes care understanding and assessment of their glycemic control than those who did not. Knowledge of one's HbA(1c) level alone, however, was not sufficient to translate increased understanding of diabetes care into the increased confidence and motivation necessary to improve patients' diabetes self-management. Strategies to provide information to patients must be combined with other behavioral strategies to motivate and help patients effectively manage their diabetes. 相似文献
998.
Mechanisms of regulation of CXCR4/SDF-1 (CXCL12)-dependent migration and homing in multiple myeloma 总被引:7,自引:0,他引:7
Alsayed Y Ngo H Runnels J Leleu X Singha UK Pitsillides CM Spencer JA Kimlinger T Ghobrial JM Jia X Lu G Timm M Kumar A Côté D Veilleux I Hedin KE Roodman GD Witzig TE Kung AL Hideshima T Anderson KC Lin CP Ghobrial IM 《Blood》2007,109(7):2708-2717
The mechanisms by which multiple myeloma (MM) cells migrate and home to the bone marrow are not well understood. In this study, we sought to determine the effect of the chemokine SDF-1 (CXCL12) and its receptor CXCR4 on the migration and homing of MM cells. We demonstrated that CXCR4 is differentially expressed at high levels in the peripheral blood and is down-regulated in the bone marrow in response to high levels of SDF-1. SDF-1 induced motility, internalization, and cytoskeletal rearrangement in MM cells evidenced by confocal microscopy. The specific CXCR4 inhibitor AMD3100 and the anti-CXCR4 antibody MAB171 inhibited the migration of MM cells in vitro. CXCR4 knockdown experiments demonstrated that SDF-1-dependent migration was regulated by the P13K and ERK/ MAPK pathways but not by p38 MAPK. In addition, we demonstrated that AMD3100 inhibited the homing of MM cells to the bone marrow niches using in vivo flow cytometry, in vivo confocal microscopy, and whole body bioluminescence imaging. This study, therefore, demonstrates that SDF-1/CXCR4 is a critical regulator of MM homing and that it provides the framework for inhibitors of this pathway to be used in future clinical trials to abrogate MM trafficking. 相似文献
999.
Summary: The significance of the EEG after epilepsy surgery is not fully understood. We investigated the as- sociation between postoperative EEG abnormalities and persistent seizures after epilepsy surgery as they relate to pathologic lesions. Among 254 patients who underwent epilepsy surgery between 1987 and 1991, we identified 78 patients who had mesiotemporal sclerosis (MTS) and 47 patients who had low-grade brain tumors, all of whom had 6-to 18-month postoperative follow-up including EEG. Patients who had other pathology, multiple operations, callosotomy, or hemispherectomy, or who were aged <18 years or who had insufficient EEG data, were excluded. Patients were classified as having persistent seizures or being seizure-free since operation. EEG abnormalities were abstracted from EEG reports 6–18 months postoperatively. Seizures persisted in 24% of the MTS group and in 27% of the tumor group. Of those with normal EEGs, none of the MTS patients and only 1 of the tumor patients had persistent seizures (p = 0.03 for MTS and p = 0.42 for tumor). Epileptiform discharges and focal slowing were associated with seizure persistence in both groups, but to a significant extent only in the MTS group. In the MTS group, patients who had both epileptiform discharges and focal slowing were more likely to have persistent seizures than were those with either abnormality alone. 相似文献
1000.
Anti-angiogenic therapies based on targeted disruption of the tumor microvascular network have been proposed for cancer treatment. Inhibitors of the endothelial cell pro-survival pathway mediated by VEGF were shown to activate caspases and cause microvascular regression, but the efficacy of this strategy can be hindered by the engagement of redundant survival pathways. Alternatively, if direct activation of an apical pro-apoptotic caspase is sufficient to disrupt microvessels in vivo, such a strategy could potentially override upstream endothelial cell survival inputs and disrupt tumor neovascular networks. Here, we fused caspase-9 to a mutated FKBP12 domain to express an inducible caspase-9 molecule (iCaspase-9) that can be activated by a cell-permeable dimerizer drug, and transduced this construct into primary endothelial cells. We found that drug-induced dimerization of iCaspase-9 is sufficient to activate endogenous caspase-3 and trigger apoptosis even when endothelial cells are treated with the pro-survival factors VEGF or bFGF. A single intraperitoneal injection of the dimerizer drug induced apoptosis of endothelial cells expressing iCaspase-9 and elimination of human microvessels engineered in immunodeficient mice. These results demonstrate that the activation of iCaspase-9 disrupts microvessels in vivo, and suggest a novel anti-angiogenic strategy based on the expression and controlled activation of an inducible death gene in neovascular endothelial cells. 相似文献