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991.
Schmidt P Pruggmayer M Steinborn A Schippert C Staboulidou I Hillemanns P Scharf A 《Archives of gynecology and obstetrics》2007,276(3):259-262
Introduction First-trimester screening according to Nicolaides uses maternal age to obtain a common background risk for trisomy 21. The
likelihood ratios by nuchal translucency, free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A are
not with respect to maternal age. It was the aim of this study to investigate if likelihood ratios should better take care
of it.
Materials Pearson’s correlation and different models of regression analysis had been performed on the results of 8,116 first-trimester
screenings. The total number of pregnancies was subdivided into three subgroups of healthy fetuses (n = 8,038); fetuses with Down’s syndrome (n = 46) and fetuses with other genetic abnormalities (n = 32). Statistical testing was applied to each of the three groups.
Results Strong independence from maternal age could be found for each of the first-trimester screening measurement parameter, as well
for healthy and as for affected fetuses. Neither Pearson’s test nor nonlinear regression models could detect a correlation.
Accordingly significance of Pearson’s test is not given.
Discussion First-trimester screening would not be improved by considering the maternal age in the calculation of the likelihood ratios.
Therefore the currently used algorithm is adequate. According, to the results, it seems to be proper as well to disregard
the maternal age in newer test strategies advanced first-trimester screening (AFS) at all. 相似文献
992.
Schmidt P Staboulidou I Soergel P Wüstemann M Hillemanns P Scharf A 《Archives of gynecology and obstetrics》2007,275(6):469-474
Objective The individual risk assessment of fetal Down’s syndrome based on measurement of nuchal translucency (NT) according to Nicolaides,
optionally complemented by the determination of PAPP-A and free beta HCG has progressively supplanted other search strategies
for fetal aneuploidies. It could be shown that this diagnostic strategy equally detects other numeric aneuploidies at a comparable
rate. A positive test result is also predictive for the presence of a fetal malformation. In this field, several computer
programs are available for clinical use. The objective of our study was to re-evaluate the first consecutive 1463 NT-risk
calculations determined by Nicolaides’ method and to compare the risk calculation to the JOY software (NT-risk calculation
module, JOY Patient Database) introduced in 2002.
Material and methods At the Department of Obstetrics and Gynecology, Hannover Medical School, 1463 consecutive complete data sets comprising first
trimester screening performed between May 2, 2000 and June 26, 2003 and corresponding fetal outcome were analysed using risk
assessment based on the Nicolaides method (PIA Fetal Database NT-Module) and compared with the risk evaluation as determined
by the JOY software (JOY Patient Database NT module). A risk exceeding 1:300 was considered to indicate the need for further
invasive testing. In a first step, only cytogenetically detectable chromosomal aberrations were analysed. Then, a second evaluation
including fetal malformations was performed.
Results Among the 1463 cases, 1445 (98.77%) fetuses revealed to be cytogenetically healthy. Both softwares showed identical detection
rates at the genetic and somatic level:13 cases of Down-Syndrome (0.89%), 2 cases of trisomy 18 (0.14%), one case of triploidy,
one Turner-Syndrome, one Klinefelter-Syndrome (0.07% each) were detected. A positive test result was found in 15 cases ending
in a spontaneous abortion, intrauterine death or peripartum death (1.03%) and in 22 cases of fetal malformation (1.50%). At
the level of genetic detection the test positive rate dropped from 92 (PIA) to 71 (JOY) (-22.8%). At the level of combined
adverse outcome the test positive rate was reduced from 100 (PIA) to 76 (JOY) (-22.0%), thus yielding in a marked improvement
of the characteristic test performance parameters.
Conclusion The novel, recently developed JOY software package allowed reliable evaluation of the risk for aneuploidy with increased specificity
whereas sensitivity was unchanged. Our data suggest an improvement of the screening for aneuploidy when using this novel software:
With an identical detection rate, the number of unnecessary invasive measures may be reduced. 相似文献
993.
Staboulidou I Soergel P Schmidt P Steinborn A Hillemanns P Scharf A 《Archives of gynecology and obstetrics》2007,276(1):35-42
Introduction
The proper function of the fetal heart is indispensable for the fetal development and the normal fetal growth. For prenatal medicine, Doppler sonography offers the possibility of a non-invasive method to examine the fetal cardiovascular function under normal and pathological circumstances. The role of the Doppler sonography is to identify those fetuses who have a high risk factor for developing a pre- or intrapartual asphyxia and therefore have to be delivered promptly. This study aimed at evaluating the clinical value of the intracardiac Doppler sonography (IDS) and at scrutinizing its usefulness during the supervision of the pregnancy of intrauterine growth restricted (IUGR) fetuses.Materials and methods
In a prospective research at the Medical School of Hanover, fetal IDS was applied to 174 pregnant women between the 21 and 37 weeks of gestation (WG). The e-wave and the a-wave, the E/A ratio, and the TVI (time velocity integral) were measured at the atrioventricular (AV) valves. The PV (peak velocity) as well as the TVI were determined at both the aortic and the pulmonary valve. Normal range curves were compiled for all measured parameters.Results
Alongside a control group with untroubled gravidity, which consisted of 153 patients, IUGR fetuses, who formed a collective of 21 patients, were Doppler sonographically examined.While the gestational age advanced, an increase of both the e-wave and the a-wave above the AV-valves could be ascertained, which lead to an E/A ratio <1. Above the semilunar valves there was indicated a slight steady increase of the TPV, the PV as well as the TVI. Normal range curves, which largely correspond to those described in the literature, were compiled for the collective of the pregnancies without pathological findings (n = 153). In comparison to the standard collective, there were no significant differences from the collective of the growth restricted fetuses (n = 21).Conclusion
A temporal informational advantage of pathological intracardiac Doppler values for high risk pregnancies (IUGR) could not be retraced in the examined collective.Doppler sonography traces acute and chronic deficits, which are indicated by hemodynamic changes of the fetus’s blood supply. The clinical importance of IDS as regards dystrophic fetuses has to be ascertained in continuative studies: In the stage of compensatory placental insufficiency (IUGR, arterial Doppler without ARED-flow, venous Doppler without pathological findings) the IDS cannot provide an informational advantage. Contrastingly, the diagnostic potential of the IDS as a screening method of fetal cardiac insufficiency during decompensative placental insufficiency (IUGR, arterial Doppler with ARED-flow, venous Doppler normal or pathological) remains indistinct and should therefore be prospectively evaluated within this high risk group and contrastingly compared to the significance of the venous Doppler sonography (informational advantage?).994.
995.
Preeclampsia is a multisystem disorder affecting about 5-10% of all pregnancies. It is a major cause of maternal, fetal and neonatal mortality and morbidity. Despite intensive research the etiology of this disease still remains unknown. Until now the inadequate transformation of the smooth-muscle cells of spiral arteries in the placental bed caused by an insufficient endovascular invasion of the trophoblast has been considered to be the major reason for the development of preeclampsia. Maternal-fetal (paternal) immune maladaptation is implicated in the insufficient trophoblast invasion, which leads to an imbalance of angiogenic and antiangiogenic factors at the maternal-fetal interface. This review summarizes the actual knowledge of important pathophysiological basic principles of preeclampsia. 相似文献
996.
997.
目的 探讨双源CT联合血清C反应蛋白(CRP)水平检测对痛风性关节炎的诊断价值。方法 选择本院2018年1月—2022年3月收治的166例疑似痛风性关节炎患者,分为痛风性关节炎组与非痛风性关节炎组行双源CT及血清CRP水平检测,以美国风湿病协会(ACR)制定的痛风性关节炎诊断标准明确痛风性关节炎诊断,计算双源CT及血清CRP单独与联合诊断痛风性关节炎的效能并分析其临床价值。结果 共有126例患者(75.90%)明确痛风性关节炎诊断。痛风性关节炎组双源CT图像绿色结晶检出率高于非痛风性关节炎组,差异有统计学意义(P<0.05)。痛风性关节炎组血清CRP水平高于非痛风性关节炎组(P<0.05),但两组血清CRP阳性率比较,差异无统计学意义(P>0.05)。双源CT联合血清CRP诊断痛风性关节炎的特异性、准确率、阳性预测值、阴性预测值均高于单项诊断,差异有统计学意义(P<0.05)。结论 双源CT联合血清CRP水平检测能够为痛风性关节炎的无创诊断提供可靠参考 相似文献
998.
The subtilase cytotoxin (SubAB) belongs to the family of AB5 toxins and is produced together with Shiga toxin (Stx) by certain Stx-producing E. coli strains (STEC). For most AB-type toxins, it is assumed that cytotoxic effects can only be induced by a complete holotoxin complex consisting of SubA and SubB. However, it has been shown for SubAB that the enzymatically active subunit SubA, without its transport and binding domain SubB, induces cell death in different eukaryotic cell lines. Interestingly, the molecular structure of SubA resembles that of the SubAB complex. SubA alone is capable of binding to cells and then being taken up autonomously. Once inside the host cell, SubA is transported, similar to the SubAB holotoxin, via a retrograde transport into the endoplasmatic reticulum (ER). In the ER, it exhibits its enzymatic activity by cleaving the chaperone BiP/GRP78 and thereby triggering cell death. Therefore, the existence of toxic single SubA subunits that have not found a B-pentamer for holotoxin assembly might improve the pathogenic potential of subtilase-producing strains. Moreover, from a pharmacological aspect, SubA might be an interesting molecule for the targeted transport of therapeutic molecules into the ER, in order to investigate and specifically modulate processes in the context of ER stress-associated diseases. Since recent studies on bacterial AB5 toxins contributed mainly to the understanding of the biology of AB-type holotoxins, this mini-review specifically focus on that recently observed single A-effect of the subtilase cytotoxin and addresses whether a fundamental shift of the traditional AB5 paradigm might be required. 相似文献
999.
Michael Müller Johann Volzke Behnam Subin Christian Johann Schmidt Hilte Geerdes-Fenge Emil Christian Reisinger Brigitte Müller-Hilke 《Viruses》2022,14(2)
While numerous studies have already compared the immune responses against SARS-CoV-2 in severely and mild-to-moderately ill COVID-19 patients, longitudinal trajectories are still scarce. We therefore set out to analyze serial blood samples from mild-to-moderately ill patients in order to define the immune landscapes for differently progressed disease stages. Twenty-two COVID-19 patients were subjected to consecutive venipuncture within seven days after diagnosis or admittance to hospital. Flow cytometry was performed to analyze peripheral blood immune cell compositions and their activation as were plasma levels of cytokines and SARS-CoV-2 specific immunoglobulins. Healthy donors served as controls. Integrating the kinetics of plasmablasts and SARS-CoV-2 specific antibodies allowed for the definition of three disease stages of early COVID-19. The incubation phase was characterized by a sharp increase in pro-inflammatory monocytes and terminally differentiated cytotoxic T cells. The latter correlated significantly with elevated concentrations of IP-10. Early acute infection featured a peak in PD-1+ cytotoxic T cells, plasmablasts and increasing titers of virus specific antibodies. During late acute infection, immature neutrophils were enriched, whereas all other parameters returned to baseline. Our findings will help to define landmarks that are indispensable for the refinement of new anti-viral and anti-inflammatory therapeutics, and may also inform clinicians to optimize treatment and prevent fatal outcomes. 相似文献
1000.
Giampaolo Merlini Violaine Planté-Bordeneuve Daniel P. Judge Hartmut Schmidt Laura Obici Stefano Perlini Jeff Packman Tara Tripp Donna R. Grogan 《Journal of cardiovascular translational research》2013,6(6):1011-1020
This phase II, open-label, single-treatment arm study evaluated the pharmacodynamics, efficacy, and safety of tafamidis in patients with non-Val30Met transthyretin (TTR) amyloidosis. Twenty-one patients with eight different non-Val30Met mutations received 20 mg QD of tafamidis meglumine for 12 months. The primary outcome, TTR stabilization at Week 6, was achieved in 18 (94.7 %) of 19 patients with evaluable data. TTR was stabilized in 100 % of patients with non-missing data at Months 6 (n?=?18) and 12 (n?=?17). Exploratory efficacy measures demonstrated some worsening of neurological function. However, health-related quality of life, cardiac biomarker N-terminal pro-hormone brain natriuretic peptide, echocardiographic parameters, and modified body mass index did not demonstrate clinically relevant worsening during the 12 months of treatment. Tafamidis was well tolerated. In conclusion, our findings suggest that tafamidis 20 mg QD effectively stabilized TTR associated with several non-Val30Met variants. 相似文献