148 research outputs found
Routine Fetal Rhd Genotyping with Maternal Plasma: A Four-Year Experience in Belgium
peer reviewedBACKGROUND: The objective was to evaluate the diagnostic value of RHD fetal genotyping from the plasma of D- mothers as soon as 10 weeks' gestation in a routine clinical practice in Belgium. STUDY DESIGN AND METHODS: A prospective study was conducted between November 2002 and December 2006. DNA extraction was performed in an automated closed tube system. Fetal RHD/SRY genotypes were detected in the plasma of 563 pregnant mothers by real-time polymerase chain reaction (PCR) targeting multiple exons 4, 5, and 10 of the RHD gene and targeting an SRY gene sequence. These were compared to the D phenotypes determined in the 581 babies they delivered. RESULTS: By combining amplification of three exons, the concordance rate of fetal RHD genotypes in maternal plasma and newborn D phenotypes at delivery was 100 percent (99.8% including one unusual false-positive). The presence of nonfunctional RHD genes and the absence of a universal fetal marker, irrespective of fetal sex, did not influence the accuracy of fetal RhD status prediction. The RHD genotyping from 18 twin pregnancies was also assessed. Five weak D women were excluded from the RHD fetal genotyping prediction. Three discrepant results (0.5%) between predicted fetal genotype and cord blood phenotype were not confirmed by the baby phenotypes from venipuncture blood. CONCLUSION: Prenatal prediction of fetal RHD by targeting multiple exons from the maternal plasma with real-time PCR is highly sensitive and accurate. Over 4 years, this experience has highly modified our management of D- pregnant women
The role of receptivity in the courtship behavior of Podocnemis erythrocephala in captivity
The courtship behavior of Podocnemis erythrocephala (Red-headed Amazon River Turtle) in captivity was studied to examine female receptivity and male response to female rejection. We observed 20 females and 39 males in 150 sessions (3β6Β h/day for a total of 450Β h). In 36% of the trials, there was no interaction between males and females, and 20% of the trials resulted in copulations. All males introduced into tanks approached females, and eventually there was aggression among the males. In 48% of the experiments, females also searched for or approached males. When males initially approached females, they either accepted the maleβs advances (14%), rejected the male passively (38%), or rejected the male aggressively (48%). In 86% of the cases where males were rejected, 4% attempted to approach females again, and in 51% they were ultimately successful
High Erk-1 activation and Gadd45a expression as prognostic markers in high risk pediatric haemolymphoproliferative diseases
Studies on activated cell-signaling pathways responsible for neoplastic transformation are numerous in solid tumors and in adult leukemias. Despite of positive results in the evolution of pediatric hematopoietic neoplasias, there are some high-risk subtypes at worse prognosis. The aim of this study was to asses the expression and activation status of crucial proteins involved in cell-signaling pathways in order to identify molecular alterations responsible for the proliferation and/or escape from apoptosis of leukemic blasts. The quantitative and qualitative expression and activation of Erk-1, c-Jun, Caspase8, and Gadd45a was analyzed, by immunocytochemical (ICC) and western blotting methods, in bone marrow blasts of 72 patients affected by acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (ALL) and stage IV non-Hodgkin Lymphoma (NHL). We found an upregulation of Erk-1, Caspase8, c-Jun, and Gadd45a proteins with a constitutive activation in 95.8%, 91.7%, 86.2%, 83.4% of analyzed specimens, respectively. It is worth noting that all AML patients showed an upregulation of all proteins studied and the high expression of GADD45a was associated to the lowest DFS median (p = 0.04). On univariate analysis, only Erk-1 phosphorylation status was found to be correlated with a significantly shorter 5-years DFS in all disease subgroups (p = 0.033) and the lowest DFS median in ALL/NHL subgroup (p = 0.04). Moreover, the simultaneous activation of multiple kinases, as we found for c-Jun and Erk-1 (r = 0.26; p = 0.025), might synergistically enhance survival and proliferation potential of leukemic cells. These results demonstrate an involvement of these proteins in survival of blast cells and, consequently, on relapse percentages of the different subgroups of patients
Survival Analysis of F98 Glioma Rat Cells Following Minibeam or Broad-Beam Synchrotron Radiation Therapy
Background: In the quest of a curative radiotherapy treatment for gliomas new delivery modes are being explored. At the Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF), a new spatially-fractionated technique, called Minibeam Radiation Therapy (MBRT) is under development. The aim of this work is to compare the effectiveness of MBRT and broad-beam (BB) synchrotron radiation to treat F98 glioma rat cells. A dose escalation study was performed in order to delimit the range of doses where a therapeutic effect could be expected. These results will help in the design and optimization of the forthcoming in vivo studies at the ESRF. Methods: Two hundred thousand F98 cells were seeded per well in 24-well plates, and incubated for 48 hours before being irradiated with spatially fractionated and seamless synchrotron x-rays at several doses. The percentage of each cell population (alive, early apoptotic and dead cells, where either late apoptotic as necrotic cells are included) was assessed by flow cytometry 48 hours after irradiation, whereas the metabolic activity of surviving cells was analyzed on days 3, 4, and 9 post-irradiation by using QBlue test. Results
Increasing incidence of childhood tumours of the central nervous system in Denmark, 1980β1996
The registered incidence rate of childhood central nervous system (CNS) tumours has increased in several countries. It is uncertain whether these increases are biologically real or owing to improved diagnostic methods. We explored the medical records of 626 CNS tumours diagnosed in Danish children between 1980 and 1996. Population-based registers were used to extract data on mortality and background population. Temporal patterns were analysed by regression techniques. Most tumours were verified by computed tomography (78%) or magnetic resonance imaging (14%). Overall, the incidence rate increased by 2.9% per year (95% confidence interval (CI): 1.3;4.5) and the mortality rate increased by 1.4% per year (95% CI: β0.4;3.3). Among children aged 0β4 years, the survival rate after diagnosis remained almost unchanged, whereas among children aged 5β14 years, the 10-year survival rate improved from 59 to 74%. These data suggest that the incidence rate of CNS tumours among Danish children has truly increased, although alternative explanations cannot be excluded
Sperm protein 17 is expressed in human nervous system tumours
BACKGROUND: Human sperm protein 17 (Sp17) is a highly conserved protein that was originally isolated from a rabbit epididymal sperm membrane and testis membrane pellet. It has recently been included in the cancer/testis (CT) antigen family, and shown to be expressed in multiple myeloma and ovarian cancer. We investigated its immunolocalisation in specimens of nervous system (NS) malignancies, in order to establish its usefulness as a target for tumour-vaccine strategies. METHODS: The expression of Sp17 was assessed by means of a standardised immunohistochemical procedure [(mAb/antigen) MF1/Sp17] in formalin-fixed and paraffin embedded surgical specimens of NS malignancies, including 28 neuroectodermal primary tumours (6 astrocytomas, 16 glioblastoma multiforme, 5 oligodendrogliomas, and 1 ependymoma), 25 meningeal tumours, and five peripheral nerve sheath tumours (4 schwannomas, and 1 neurofibroma),. RESULTS: A number of neuroectodermal (21%) and meningeal tumours (4%) were found heterogeneously immunopositive for Sp17. None of the peripheral nerve sheath tumours was immunopositive for Sp17. The expression pattern was heterogeneous in all of the positive samples, and did not correlate with the degree of malignancy. CONCLUSION: The frequency of expression and non-uniform cell distribution of Sp17 suggest that it cannot be used as a unique immunotherapeutic target in NS cancer. However, our results do show the immunolocalisation of Sp17 in a proportion of NS tumour cells, but not in their non-pathological counterparts. The emerging complex function of Sp17 makes further studies necessary to clarify the link between it and immunopositive cells
Temporal resolution of proteinβprotein interactions in the live-cell plasma membrane
We have recently devised a method to quantify interactions between a membrane protein (βbaitβ) and a fluorophore-labeled protein (βpreyβ) directly in the live-cell plasma membrane (Schwarzenbacher et al. Nature Methods 5:1053β1060 2008). The idea is to seed cells on surfaces containing micro-patterned antibodies against the exoplasmic domain of the bait, and monitor the co-patterning of the fluorescent prey via fluorescence microscopy. Here, we characterized the time course of bait and prey micropattern formation upon seeding the cells onto the micro-biochip. Patterns were formed immediately after contact of the cells with the surface. Cells were able to migrate over the chip surface without affecting the micropattern contrast, which remained constant over hours. On single cells, bait contrast may be subject to fluctuations, indicating that the bait can be released from and recaptured on the micropatterns. We conclude that interaction studies can be performed at any time-point ranging from 5Β min to several hours post seeding. Monitoring interactions with time opens up the possibility for new assays, which are briefly sketched in the discussion section
Release of Intracellular Calcium Stores Facilitates Coxsackievirus Entry into Polarized Endothelial Cells
Group B coxsackieviruses (CVB) are associated with viral-induced heart disease and are among the leading causes of aseptic meningitis worldwide. Here we show that CVB entry into polarized brain microvasculature and aortic endothelial cells triggers a depletion of intracellular calcium stores initiated through viral attachment to the apical attachment factor decay-accelerating factor. Calcium release was dependent upon a signaling cascade that required the activity of the Src family of tyrosine kinases, phospholipase C, and the inositol 1,4,5-trisphosphate receptor isoform 3. CVB-mediated calcium release was required for the activation of calpain-2, a calcium-dependent cysteine protease, which controlled the vesicular trafficking of internalized CVB particles. These data point to a specific role for calcium signaling in CVB entry into polarized endothelial monolayers and highlight the unique signaling mechanisms used by these viruses to cross endothelial barriers
Implementing academic detailing for breast cancer screening in underserved communities
<p>Abstract</p> <p>Background</p> <p>African American and Hispanic women, such as those living in the northern Manhattan and the South Bronx neighborhoods of New York City, are generally underserved with regard to breast cancer prevention and screening practices, even though they are more likely to die of breast cancer than are other women. Primary care physicians (PCPs) are critical for the recommendation of breast cancer screening to their patients. Academic detailing is a promising strategy for improving PCP performance in recommending breast cancer screening, yet little is known about the effects of academic detailing on breast cancer screening among physicians who practice in medically underserved areas. We assessed the effectiveness of an enhanced, multi-component academic detailing intervention in increasing recommendations for breast cancer screening within a sample of community-based urban physicians.</p> <p>Methods</p> <p>Two medically underserved communities were matched and randomized to intervention and control arms. Ninety-four primary care community (<it>i.e</it>., not hospital based) physicians in northern Manhattan were compared to 74 physicians in the South Bronx neighborhoods of the New York City metropolitan area. Intervention participants received enhanced physician-directed academic detailing, using the American Cancer Society guidelines for the early detection of breast cancer. Control group physicians received no intervention. We conducted interviews to measure primary care physicians' self-reported recommendation of mammography and Clinical Breast Examination (CBE), and whether PCPs taught women how to perform breast self examination (BSE).</p> <p>Results</p> <p>Using multivariate analyses, we found a statistically significant intervention effect on the recommendation of CBE to women patients age 40 and over; mammography and breast self examination reports increased across both arms from baseline to follow-up, according to physician self-report. At post-test, physician involvement in additional educational programs, enhanced self-efficacy in counseling for prevention, the routine use of chart reminders, computer- rather than paper-based prompting and tracking approaches, printed patient education materials, performance targets for mammography, and increased involvement of nursing and other office staff were associated with increased screening.</p> <p>Conclusion</p> <p>We found some evidence of improvement in breast cancer screening practices due to enhanced academic detailing among primary care physicians practicing in urban underserved communities.</p
An intranasal selective antisense oligonucleotide impairs lung cyclooxygenase-2 production and improves inflammation, but worsens airway function, in house dust mite sensitive mice
<p>Abstract</p> <p>Background</p> <p>Despite its reported pro-inflammatory activity, cyclooxygenase (COX)-2 has been proposed to play a protective role in asthma. Accordingly, COX-2 might be down-regulated in the airway cells of asthmatics. This, together with results of experiments to assess the impact of COX-2 blockade in ovalbumin (OVA)-sensitized mice in vivo, led us to propose a novel experimental approach using house dust mite (HDM)-sensitized mice in which we mimicked altered regulation of COX-2.</p> <p>Methods</p> <p>Allergic inflammation was induced in BALBc mice by intranasal exposure to HDM for 10 consecutive days. This model reproduces spontaneous exposure to aeroallergens by asthmatic patients. In order to impair, but not fully block, COX-2 production in the airways, some of the animals received an intranasal antisense oligonucleotide. Lung COX-2 expression and activity were measured along with bronchovascular inflammation, airway reactivity, and prostaglandin production.</p> <p>Results</p> <p>We observed impaired COX-2 mRNA and protein expression in the lung tissue of selective oligonucleotide-treated sensitized mice. This was accompanied by diminished production of mPGE synthase and PGE<sub>2 </sub>in the airways. In sensitized mice, the oligonucleotide induced increased airway hyperreactivity (AHR) to methacholine, but a substantially reduced bronchovascular inflammation. Finally, mRNA levels of hPGD synthase remained unchanged.</p> <p>Conclusion</p> <p>Intranasal antisense therapy against COX-2 in vivo mimicked the reported impairment of COX-2 regulation in the airway cells of asthmatic patients. This strategy revealed an unexpected novel dual effect: inflammation was improved but AHR worsened. This approach will provide insights into the differential regulation of inflammation and lung function in asthma, and will help identify pharmacological targets within the COX-2/PG system.</p
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