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Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system.  相似文献   
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Zusammenfassung Es wird eine Methode beschrieben, die eine fortlaufende Aufzeichnung der Pupillenbewegungen beim Menschen ermöglicht.Es wird die Reaktion der Pupille auf einen kurz dauernden Lichtblitz und auf eine längerdauernde Belichtung bei verschiedenen gesunden Versuchspersonen aufgezeichnet und eingehend beschrieben.Durch gleichzeitige Registrierung an beiden Augen wird der Verlauf von konsensueller und direkter Lichtreaktion miteinander verglichen.Die Latenzzeit der Pupillenreaktion auf Licht und Verdunkelung wird bestimmt.Die Reaktion der Pupille auf Lidschlu\ wird registriert und mit dem Lichtreflex verglichen.Es wird die Konvergenzreaktion der Pupille gleichzeitig mit der Konvergenzbewegung des Auges registriert und beschrieben.  相似文献   
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BACKGROUND & AIMS: Collagenous colitis (CC) is a well-described entity causing chronic diarrhea and characteristic histologic findings. Several treatment options have been suggested, but no controlled data are available. We conducted a placebo-controlled trial to show the clinical and histologic effects of budesonide in CC. METHODS: Twenty-eight patients were randomly assigned to receive placebo (n = 14) or budesonide 9 mg daily (n = 14) for 8 weeks. Patients were evaluated clinically, and blinded biopsy specimens were analyzed from fixed locations at weeks 0 and 8. Clinical response was defined as a decrease of at least 50% in the disease activity score (number of bowel movements in the last 7 days). At week 8, nonresponders received open-label budesonide for the next 8-week period; responders discontinued treatment and were followed up. RESULTS: Three patients discontinued the study prematurely. Intention-to-treat analysis showed clinical response in 8 of 14 patients in the budesonide group compared with 3 of 14 responders for placebo (P = 0.05) after 8 weeks of blinded therapy, together with improved stool consistency. Histologically, there was no change in the mean thickness of the collagen band but a significant decrease of the lamina propria infiltrate in the budesonide group (P < 0.001). CONCLUSIONS: Budesonide is efficacious in inducing short-term clinical response in CC with significant reduction of the histologic infiltrate in the lamina propria.  相似文献   
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Antiinflammatory Effects of Murine Malignant Cells   总被引:21,自引:4,他引:21       下载免费PDF全文
Development of teratocarcinoma does not impair immunization of mice against Listeria monocytogenes. Endotoxin injection a short time before tumor cell inoculation allows the growth of teratocarcinoma in non syngenic mice despite immune stimulation. In contrast with this absence of impaired systematic immunity, teratocarcinoma cells were found to repulse macrophages in vitro. This effect on macrophages was also found with three other malignant cells and with trophoblast cells. In vivo, teratocarcinoma cells were found to impair local inflammation. These cells and other malignant cells are able to produce a compound(s) of molecular weight between 10(3) and 10(4), which prevents inflammatory reaction. These results suggest that mouse teratocarcinomas and other tumors by-pass the host immunological system of surveillance by at least two mechanisms: a direct toxic effect on macrophages and the release of an inhibitor of inflammation. The possible relations between these properties of malignant cells and physiological functions of trophoblast are discussed.  相似文献   
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Parental incarceration is associated with mental and physical health problems in children, yet little research directly tests mechanisms through which parental incarceration could imperil child health. We hypothesized that the incarceration of a woman or her romantic partner in the year before birth constituted an additional hardship for already-disadvantaged women, and that these additionally vulnerable women were less likely to engage in positive perinatal health behaviors important to infant and early childhood development. We analyzed 2006–2010 data from the Pregnancy Risk Assessment and Monitoring System to assess the association between incarceration in the year prior to the birth of a child and perinatal maternal hardships and behaviors. Women reporting incarceration of themselves or their partners in the year before birth of a child had .86 the odds (95 % CI .78–.95) of beginning prenatal care in the first trimester compared to women not reporting incarceration. They were nearly twice as likely to report partner abuse and were significantly more likely to rely on WIC and/or Medicaid for assistance during pregnancy. These associations persist after controlling for socioeconomic measures and other stressors, including homelessness and job loss. Incarceration of a woman or her partner in the year before birth is associated with higher odds of maternal hardship and poorer perinatal health behaviors. The unprecedented scale of incarceration in the US simultaneously presents an underutilized public health opportunity and constitutes a social determinant of health that may contribute to disparities in early childhood development.  相似文献   
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The frequency following response (FFR), a scalp-recorded measure of phase-locked brainstem activity, is often assumed to reflect the pitch of sounds as perceived by humans. In two experiments, we investigated the characteristics of the FFR evoked by complex tones. FFR waveforms to alternating-polarity stimuli were averaged for each polarity and added, to enhance envelope, or subtracted, to enhance temporal fine structure information. In experiment 1, frequency-shifted complex tones, with all harmonics shifted by the same amount in Hertz, were presented diotically. Only the autocorrelation functions (ACFs) of the subtraction-FFR waveforms showed a peak at a delay shifted in the direction of the expected pitch shifts. This expected pitch shift was also present in the ACFs of the output of an auditory nerve model. In experiment 2, the components of a harmonic complex with harmonic numbers 2, 3, and 4 were presented either to the same ear (“mono”) or the third harmonic was presented contralaterally to the ear receiving the even harmonics (“dichotic”). In the latter case, a pitch corresponding to the missing fundamental was still perceived. Monaural control conditions presenting only the even harmonics (“2 + 4”) or only the third harmonic (“3”) were also tested. Both the subtraction and the addition waveforms showed that (1) the FFR magnitude spectra for “dichotic” were similar to the sum of the spectra for the two monaural control conditions and lacked peaks at the fundamental frequency and other distortion products visible for “mono” and (2) ACFs for “dichotic” were similar to those for “2 + 4” and dissimilar to those for “mono.” The results indicate that the neural responses reflected in the FFR preserve monaural temporal information that may be important for pitch, but provide no evidence for any additional processing over and above that already present in the auditory periphery, and do not directly represent the pitch of dichotic stimuli.  相似文献   
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