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61.
Fenella J. Kirkham Dimitrios Zafeiriou David Howe Philippa Czarpran Ashley Harris Roxanna Gunny Brigitte Vollmer 《European journal of paediatric neurology》2018,22(6):989-1005
Fetal stroke is an important cause of cerebral palsy but is difficult to diagnose unless imaging is undertaken in pregnancies at risk because of known maternal or fetal disorders. Fetal ultrasound or magnetic resonance imaging may show haemorrhage or ischaemic lesions including multicystic encephalomalacia and focal porencephaly. Serial imaging has shown the development of malformations including schizencephaly and polymicrogyra after ischaemic and haemorrhagic stroke. Recognised causes of haemorrhagic fetal stroke include alloimmune and autoimmune thrombocytopaenia, maternal and fetal clotting disorders and trauma but these are relatively rare. It is likely that a significant proportion of periventricular and intraventricular haemorrhages are of venous origin. Recent evidence highlights the importance of arterial endothelial dysfunction, rather than thrombocytopaenia, in the intraparenchymal haemorrhage of alloimmune thrombocytopaenia. In the context of placental anastomoses, monochorionic diamniotic twins are at risk of twin twin transfusion syndrome (TTTS), or partial forms including Twin Oligohydramnios Polyhydramnios Sequence (TOPS), differences in estimated weight (selective Intrauterine growth Retardation; sIUGR), or in fetal haemoglobin (Twin Anaemia Polycythaemia Sequence; TAPS). There is a very wide range of ischaemic and haemorrhagic injury in a focal as well as a global distribution. Acute twin twin transfusion may account for intraventricular haemorrhage in recipients and periventricular leukomalacia in donors but there are additional risk factors for focal embolism and cerebrovascular disease. The recipient has circulatory overload, with effects on systemic and pulmonary circulations which probably lead to systemic and pulmonary hypertension and even right ventricular outflow tract obstruction as well as the polycythaemia which is a risk factor for thrombosis and vasculopathy. The donor is hypovolaemic and has a reticulocytosis in response to the anaemia while maternal hypertension and diabetes may influence stroke risk. Understanding of the mechanisms, including the role of vasculopathy, in well studied conditions such as alloimmune thrombocytopaenia and monochorionic diamniotic twinning may lead to reduction of the burden of antenatally sustained cerebral palsy. 相似文献
62.
63.
Harald Treuer Martin Kocher Moritz Hoevels Stefan Hunsche Klaus Luyken Mohammad Maarouf Jürgen Voges Rolf-Peter Müller Volker Sturm 《Radiotherapy and oncology》2006,81(1):25-32
OBJECTIVE: Determination of the impact of inaccuracies in the determination and setup of the target point in stereotactic radiosurgery (SRS) on the expectable complication and control probabilities. METHODS: Two randomized samples of patients with arteriovenous malformation (AVM) (n=20) and with brain metastases (n=20) treated with SRS were formed, and the probability for complete obliteration (COP) or complete remission (CRP), the size of the 10 Gy-volume in the brain tissue (VOI10), and the probability for radiation necrosis (NTCP) were calculated. The dose-effect relations for COP and CRP were fitted to clinical data. Target point deviations were simulated through random vectors and the resulting probabilities and volumes were calculated and compared with the values of the treatment plan. RESULTS: The decrease of the relative value of the control probabilities at 1mm target point deviation was up to 4% for AVMs and up to 10% for metastases. At 2 mm the median decrease was 5% for AVMs and 9% for metastases. The value for the target point deviation, at which COP and CRP decreased about 0.05 in 90% of the cases, was 1.3 mm. The increase of NTCP was maximally 0.0025 per mm target point deviation for AVMs and 0.0035/mm for metastases. The maximal increase of VOI10 was 0.7 cm(3)/mm target point deviation in both patient groups. CONCLUSIONS: The upper limit for tolerable target point deviations is at 1.3mm. If this value cannot be achieved during the system test, a supplementary safety margin should be applied for the definition of the target volume. A better accuracy level is desirable, in order to ensure optimal chances for the success of the treatment. The target point precision is less important for the minimization of the probability of radiation necroses. 相似文献
64.
Volkmar Müller Sabine Riethdorf Brigitte Rack Wolfgang Janni Peter A Fasching Erich Solomayer Bahriye Aktas Sabine Kasimir-Bauer Klaus Pantel Tanja Fehm 《Breast cancer research : BCR》2012,14(4):1-8
Introduction
There is a multitude of assays for the detection of circulating tumor cells (CTCs) but a very limited number of studies comparing the clinical relevance of results obtained with different test methods. The DETECT trial for metastatic breast cancer patients was designed to directly compare the prognostic impact of two commercially available CTC assays that are prominent representatives of immunocytochemical and RT-PCR based technologies.Methods
In total, 254 metastatic breast cancer patients were enrolled in this prospective multicenter trial. CTCs were assessed using both the AdnaTest Breast Cancer and the CellSearch system according to the manufacturers' instructions.Results
With the CellSearch system, 116 of 221 (50%) evaluable patients were CTC-positive based on a cut-off level at 5 or more CTCs. The median overall survival (OS) was 18.1 months in CTC-positive patients. (95%-CI: 15.1-22.1 months) compared to 27 months in CTC-negative patients (23.5-30.7 months; p<0.001). This prognostic impact for OS was also significant in the subgroups of patients with triple negative, HER2-positive and hormone receptor-positive/HER2-negative primary tumors. The progression free survival (PFS) was not correlated with CTC status in our cohort receiving different types and lines of systemic treatment (p = 0.197). In multivariate analysis, the presence of CTCs was an independent predictor for OS (HR: 2.7, 95%-CI: 1.6-4.2). When the AdnaTest Breast was performed, 88 of 221 (40%) patients were CTC-positive. CTC-positivity assessed by the AdnaTest Breast had no association with PFS or OS.Conclusions
The prognostic relevance of CTC detection in metastatic breast cancer patients depends on the test method. The present results indicate that the CellSearch system is superior to the AdnaTest Breast Cancer in predicting clinical outcome in advanced breast cancer.Trial registration
Current Controlled Trials Registry number ISRCTN59722891. 相似文献65.
Pesty A Broca O Poirot C Lefèvre B 《Reproductive sciences (Thousand Oaks, Calif.)》2008,15(7):661-672
The dynamics of the subcellular distribution of PLCbeta1 was investigated during meiosis competence acquisition and meiosis resumption in relation to oocyte diameter and to nonsurrounded-nucleolus or surrounded-nucleolus chromatin configurations. Oocytes collected after both in vivo and in vitro folliculogenesis were studied. In both conditions, at the beginning of the process, most oocytes exhibited a nuclear PLCbeta 1 associated with a nonsurrounded-nucleolus chromatin configuration. Then at the final stage of the process, the factors shifted mainly toward a cytoplasmic PLCbeta1 and a surrounded-nucleolus chromatin configuration, typical of a preovulatory fertilizable oocyte. Additionally, only germinal vesicle oocytes with a diameter > 75 microm, and exhibiting cytoplasmic PLC beta1 distribution and surrounded-nucleolus chromatin configuration, resumed meiosis. Our findings demonstrate a strong correlation between oocyte diameter, chromatin configuration, and PLCbeta1 localization. Thus, PLCbeta1 localization appears to be a key factor determining the progressive acquisition of meiotic competence and final resumption of meiosis. 相似文献
66.
67.
Simon-Bouy B Taillandier A Fauvert D Brun-Heath I Serre JL Armengod CG Bialer MG Mathieu M Cousin J Chitayat D Liebelt J Feldman B Gérard-Blanluet M Körtge-Jung S King C Laivuori H Le Merrer M Mehta S Jern C Sharif S Prieur F Gillessen-Kaesbach G Zankl A Mornet E 《Prenatal diagnosis》2008,28(11):993-998
OBJECTIVE: We studied hypophosphatasia (HP) mutations in 19 cases prenatally detected by ultrasonography without familial history of HP. We correlated the mutations with the reported ultrasound signs, and discussed genetic counseling with regard to the particular dominantly inherited prenatal benign form of HP. METHOD: The coding sequence of the tissue nonspecific alkaline phosphatase (TNSALP) gene was analyzed by DNA sequencing, and 3D modeling was used to locate the mutated amino acids with regard to the functional domains of TNSALP. RESULTS: Although reported ultrasound signs were heterogeneous, two mutated alleles were found in 18 of the 19 cases studied, indicating recessive transmission of the disease. Functional domains of TNSALP were affected by 74% of missense mutations. In all the cases, including one with only a heterozygous mutation, molecular, biological, and familial data do not corroborate the hypothesis of prenatal benign HP. The mutation c.1133A>T observed in the prenatal benign form of HP and common in USA was not found in this series. CONCLUSION: The results point out the prenatally detectable allelic heterogeneity of HP. The nature of the detected mutations and the evidence of recessive inheritance do not support these cases being affected with prenatal benign HP. 相似文献
68.
Intraperitoneal hyperthermic chemotherapy using carboplatin: a phase I analysis in ovarian carcinoma 总被引:2,自引:0,他引:2
OBJECTIVE: Cyclic platinum-based intraperitoneal chemotherapy has proven to be effective after optimal surgical cytoreduction in ovarian carcinoma. Hyperthermia is directly cytotoxic and enhances chemotherapy tumoricidal effects. This study was designed to determine the maximum tolerated dose (MTD) of carboplatin used intraoperatively as intraperitoneal hyperthermic chemotherapy (IPHC), the effect on postoperative systemic chemotherapy administration, and the potential for repeat IPHC at second look surgery. METHODS: Using the ThermoChem HT System, escalating doses of carboplatin (400, 600, 800, 1000, and 1200 mg/m(2)) were administered intraoperatively as IPHC with a perfusion time of 90 min. A subgroup of eight patients that received initial IPHC and subsequent systemic chemotherapy underwent second look reassessment surgery with IPHC. RESULTS: The first 4 dose levels were well tolerated without dose-defining toxicity. The initial two patients treated at 1200 mg/m(2) developed grade 4 myelosuppression thus defining the MTD at 1000 mg/m(2). Newly diagnosed ovarian cancer patients receiving the initial IPHC at the MTD defined above completed standard systemic chemotherapy with six courses of systemic chemotherapy. Eight patients having initial IPHC and systemic chemotherapy subsequently had repeat IPHC performed at second look laparotomy without grade 3 or 4 toxicities. Four patients were found to have extensive adhesions at the time of second look reassessment surgery yet completed IPHC. CONCLUSIONS: The MTD for intraperitoneal carboplatin administered as IPHC was established at 1000 mg/m(2). IPHC at the initial cytoreductive procedure did not preclude subsequent systemic chemotherapy. In addition, repetitive IPHC was feasible at second look reassessment surgery. 相似文献
69.
70.
Favre R Duchange N Vayssière C Kohler M Bouffard N Hunsinger MC Kohler A Mager C Neumann M Vayssière C Viville B Hervé C Moutel G 《Prenatal diagnosis》2007,27(3):197-205
OBJECTIVES: To evaluate the level of information and informed consent for maternal serum screening (MSS) for Down syndrome (DS) in the second trimester of pregnancy and analyse the exercise of autonomy towards the test by the women concerned. METHODS: We studied the population of pregnant women attending obstetric consultations in two French hospitals over a 3-month period. The women were assigned to three groups according to MSS results for DS: women at high risk of having a child with DS (group 1), women at low risk (group 2) and women who did not undergo the test (group 3). A questionnaire was completed before the medical consultation, to assess the quality of consent before amniocentesis for the group at high risk and before the second-trimester ultrasound scan for the other two groups. RESULTS: We analysed 305 questionnaires for 89, 137 and 79 women belonging to groups 1, 2 and 3 respectively. In total, 123 women (40.3% [IC 95%, 35-46%]) were considered to be well informed; 33 (10%, [IC 95%, 8-12%]) had a high level of knowledge, but made choices not consistent with their stated attitude, and 149 (49.7% [IC 95%, 45-56%]) were considered uninformed. Logistic regression analysis showed that maternal consent depended on three independent components: The score attributed to the doctor for information about MSS (t = 4.216, p < 0.001).Whether the patient belonged to group 1 (t = -2.631, p < 0.009).Educational level (< high-school diploma, high-school diploma or at least two years of higher education after high school) (t = 2.324, p < 0.02). The rate of consent increased with educational level and was highest for the women in group 1 and for those whose doctor had a high information score. CONCLUSIONS: Our findings clearly show that women are provided with insufficient information concerning MSS screening for DS in the second trimester of pregnancy for real and valid consent to be obtained. 相似文献