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21.
Polyamine metabolism in gliomas 总被引:2,自引:0,他引:2
Ralf-Ingo Ernestus Gabriele Röhn Roland Schröder Thomas Els Jin-Yul Lee Norfrid Klug Wulf Paschen 《Journal of neuro-oncology》1996,29(2):167-174
Summary Biosynthesis of the polyamines putrescine, spermidine, and spermine has been found to be activated in tissues with cellular proliferation. In the present study we have investigated polyamine levels and the activity of the first rate-limiting enzyme ornithine decarboxylase (ODC) in tumour samples obtained during operation of 202 patients with gliomas. Biochemical data were closely related to the grading of malignancy and to the morphological characteristics of each sample. Mean ODC activity was significantly higher in all gliomas as compared to peritumoural non-neoplastic brain. Furthermore, it was significantly higher (p 0.001) in anaplastic gliomas who grade III and IV (9.0 ± 9.6 nmol/g/h) than in gliomas WHO grade I and II (3.3 ± 4.2 nmol/g/h). Highest enzyme activity (58.5 nmol/g/h) was found in solid and vital parts of malignant tumours, whereas predominantly necrotic areas exhibited low ODC activity (< 1 nmol/g/h). Thus, intra- and interindividual variability of ODC activity corresponded well to histomorphological heterogeneity in high-grade gliomas. Putrescine levels also increased with rising grade of malignancy, whereas spermidine and spermine levels did not correlate with the histological grading. In conclusion, high ODC activity represents a biochemical marker of malignancy in gliomas, but low values do not prove benignity. The present study reinforces the need of further and more extensive tumour sampling closely related to follow-up investigations in the heterogeneous group of gliomas. 相似文献
22.
Elevated expression of carcinoembryonic antigen-related cell adhesion molecule 1 promotes progression of non-small cell lung cancer. 总被引:7,自引:0,他引:7
Wulf Sienel Sebastian Dango Ute Woelfle Alicia Morresi-Hauf Christoph Wagener Jens Brümmer Wolf Mutschler Bernward Passlick Klaus Pantel 《Clinical cancer research》2003,9(6):2260-2266
PURPOSE: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM-1) has recently been implicated in cancer development and progression. This study was performed to assess whether CEACAM-1 expression in primary tumors is correlated to long-term survival in patients with operable non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Primary tumors of 145 consecutive patients with completely resected NSCLC (pT(1-4) pN(0-2) M(0) R(0)) were stained immunohistochemically using the monoclonal anti-CEACAM-1 antibody 4D1/C2. The prognostic relevance of CEACAM-1 expression was evaluated by univariate Kaplan-Meier and multivariate Cox regression analysis. The median follow-up period was 72 months (range, 10-130 months). RESULTS: Normal bronchiolar epithelium present in all sections exhibited no immunostaining. In contrast, 73 tumors (50.4%) showed between 1 and 66% CEACAM-1 positive tumor cells, and 72 tumors (49.6%) exhibited even a higher percentage of positive tumor cells. A high CEACAM-1 expression rate (i.e., >/=66% positive tumor cells) was more frequent in adenocarcinomas than in squamous cell carcinomas (61.9 versus 35.7%, respectively). Multivariate Cox regression analysis demonstrated that CEACAM-1 represents an independent prognosticator for cancer-related survival (P = 0.018; relative risk, 1.8; 95% confidence interval, 1.1-2.8). Subgroup analysis revealed that a high CEACAM-1 expression rate was of significant prognostic impact in pN(1)-pN(2) patients (n = 60; P = 0.024), pT(3)-pT(4) patients (n = 22; P = 0.009), and stage IIa-IIIa patients (n = 69; P = 0.012). CONCLUSIONS: The absence of CEACAM-1 in normal lung tissue and its expression in tumor cells argues against a tumor-suppressive role of CEACAM-1 in NSCLC. The correlation between elevated CEACAM-1 expression and an unfavorable prognosis indicates rather that CEACAM-1 might promote lung cancer progression. 相似文献
23.
J?rn Wulf Ulrich H?dinger Ulrich Oppitz Wibke Thiele Michael Flentje 《Radiotherapy and oncology》2003,66(2):141-150
BACKGROUND AND PURPOSE: Previous analyses of target reproducibility in extracranial stereotactic radiotherapy have revealed standard security margins for planning target volume (PTV) definition of 5mm in axial and 5-10mm in longitudinal direction. In this study the reproducibility of the clinical target volume (CTV) of lung and liver tumors within the PTV over the complete course of hypofractionated treatment is evaluated. The impact of target mobility on dose to the CTV is assessed by dose-volume histograms (DVH). MATERIALS AND METHODS: Twenty-two pulmonary and 21 hepatic targets were treated with three stereotactic fractions of 10 Gy to the PTV-enclosing 100%-isodose with normalization to 150% at the isocenter. A conformal dose distribution was related to the PTV, which was defined by margins of 5-10mm added to the CTV. Prior to each fraction a computed tomography (CT)-simulation over the complete target volume was performed resulting in a total of 60 CT-simulations for lung and 58 CT-simulations for hepatic targets. The CTV from each CT-simulation was segmented and matched with the CT-study used for treatment planning. A DVH of the simulated CTV was calculated for each fraction. The target coverage (TC) of dose to the simulated CTV was defined as the proportion of the CTV receiving at least the reference dose (100%). RESULTS: A decrease of TC to <95% was found in 3/60 simulations (5%) of pulmonary and 7/58 simulations (12%) of hepatic targets. In two of 22 pulmonary targets (9%) and in four of 21 hepatic targets (19%) a TC of <95% occurred in at least one fraction. At risk for a decreased TC <95% were pulmonary targets with increased breathing mobility and hepatic targets with a CTV exceeding 100 cm(3). CONCLUSIONS: Target reproducibility was precise within the reference isodose in 91% of lung and 81% of liver tumors with a TC of the complete CTV >or=95% at each fraction of treatment. Pulmonary targets with increased breathing mobility and liver tumors >100 cm(3) are at risk for target deviation exceeding the standard security margins for PTV-definition at least for one fraction and require individual evaluation of sufficient margins. 相似文献
24.
Zum Thema
Im Vergleich der Perinatalerhebungen mit früheren Jahren ist eine zunehmende Verschiebung zu Gunsten der Sektio zu beobachten,
ohne da? damit ein weiterer Abfall der kindlichen Mortalit?t verbunden ist. Es ist anzunehmen, da? der Rückgang der mütterlichen
Mortalit?t und postoperativen Letalit?t zu einer gro?zügigeren Indikationsstellung geführt hat. So hat inzwischen die kindliche
Indikation zum Kaiserschnitt die mütterliche überflügelt.
Die in der Perinatalerhebung am h?ufigsten angegebenen Risiken für die Indikation einer Entbindung durch Sektio sind das pathologische
CTG, die protrahierte Geburt und die Beckenendlage. Beim pathologischen CTG ist gleichzeitig ein Rückgang der vaginaloperativen
Entbindungen zu beobachten. Trotzdem wurden die perinatale Mortalit?t und Frühmorbidit?t nicht verbessert!
Der protrahierte Geburtsverlauf als Sektioindikation unterliegt sehr der subjektiven Beurteilung. Eine l?ngere Geburtsdauer
wird heutzutage trotz erheblich verbesserter Analgesiem?glichkeiten immer weniger akzeptiert. Auch bei protrahierter Austreibungsperiode
steigt die Rate der Kaiserschnitte an bei parallel dazu absinkender Zahl vaginal-operativer Geburtsbeendigungen.
Für die Geburtsleitung bei Beckenendlagen finden sich von Klinik zu Klinik erhebliche Differenzen. Für Erstgeb?rende werden
Sektioraten zwischen 7 % und 100 % angegeben. Insgesamt hat aber die Zunahme vaginaler BEL-Entbindungen durch erfahrene Geburtshelfer
zu einem drastischen Rückgang prim?rer Kaiserschnitte geführt, ohne da? dadurch die Rate der sekund?ren Sektiones angestiegen
ist.
Der sprunghafte Anstieg der Frühgeburten steht im Zusammenhang mit der ?nderung des Personenstandsgesetzes, wonach auch Frühgeburten
unter 1000 g in die Perinatalerhebung einbezogen werden müssen. Dennoch bleibt die Sektiorate bei den Frühgeburten mit 0,8–0,9
% der Gesamtgeburtenzahl unver?ndert.
Die Gründe für eine Zunahme der Sektiofrequenz liegen nicht zuletzt auch im au?ermedizinischen Bereich, z. B. in mangelnder
apparativer und personeller Ausstattung der Klinikabteilungen für eine Intensivbetreuung rund um die Uhr. Unumwunden wird
aber auch zugestanden, da? h?ufig forensische Aspekte bei der Indikationsstellung eine Rolle spielen. 相似文献
25.
Except in emergencies, the medical treatment of incompetent patients also has to be based upon an informed consent between the physician and a legitimate legal representative (durable power of attorney). Consequently, the German 'Betreuungsrecht' advices persons to designate in advance such a proxy or surrogate. However, an additional court-decision is demanded, if a medical measure poses significant risks for the future health or the life of the incompetent patient. On the base of the available epidemiologic data we illustrate that neither our medical nor our legal system could realistically cope with the practical consequences of this legislation: The vast majority of our present decisions in such cases is not covered by a legally valid informed consent, which implies possible forensic consequences. This article provides relevant clinical and legal advice on how to protect the legitimate interests of all concerned within the present framework, which should urgently be revised. 相似文献
26.
John Lasekan Yong Choe Svyatoslav Dvoretskiy Amy Devitt Sue Zhang Amy Mackey Karyn Wulf Rachael Buck Christine Steele Michelle Johnson Geraldine Baggs 《Nutrients》2022,14(13)
Background: Five of the most abundant human milk oligosaccharides (HMOs) in human milk are 2′-fucosyllactose (2′-FL), 3-fucosyllactose (3-FL), lacto-N-tetraose (LNT), 3′-sialyllactose (3′-SL) and 6′-sialyllactose (6′-SL). Methods: A randomized, double-blind, controlled parallel feeding trial evaluated growth in healthy term infants fed a control milk-based formula (CF; n = 129), experimental milk-based formula (EF; n = 130) containing five HMOs (5.75 g/L; 2′-FL, 3-FL, LNT, 3′-SL and 6′-SL) or human milk (HM; n = 104). Results: No significant differences (all p ≥ 0.337, protocol evaluable cohort) were observed among the three groups for weight gain per day from 14 to 119 days (D) of age, irrespective of COVID-19 or combined non-COVID-19 and COVID-19 periods. There were no differences (p ≥ 0.05) among the three groups for gains in weight and length from D14 to D119. Compared to the CF group, the EF group had more stools that were soft, frequent and yellow and were similar to the HM group. Serious and non-serious adverse events were not different among groups, but more CF-fed infants were seen by health care professionals for illness from study entry to D56 (p = 0.044) and D84 (p = 0.028) compared to EF-fed infants. Conclusions: The study demonstrated that the EF containing five HMOs supported normal growth, gastrointestinal (GI) tolerance and safe use in healthy term infants. 相似文献
27.
28.
Antibodies against follicle-stimulating hormone (anti-FSH) are present in infertile female sera. Follicle-stimulating hormone as antigen is present in female sera and introduced to the genital tract mucosa as a constituent of semen. The female immune system is activated by semen constituents during insemination to induce mucosal tolerance. We found that circulating anti-FSH IgA correlated with IgA against sperm surface antigens in female patients undergoing IVF. Our results suggest that anti-FSH and anti-sperm IgA could share antigenic origin, being induced possibly by mucosal tolerance to semen. 相似文献
29.
Bergman E Kieler H Petzold M Sonesson C Axelsson O 《Acta obstetricia et gynecologica Scandinavica》2007,86(6):671-677
BACKGROUND: Antenatal identification of infants small for gestational age (SGA) improves their perinatal outcome. Repeated measurement of symphysis-fundus (SF) heights performed by midwives is the most widespread screening method for detection of SGA. However, the inefficiency of this method necessitates improved practices. Earlier start and more frequent SF measurements, which could be accomplished by self-administered measurements, might improve the ability to detect deviant growth. The present study was set up to evaluate whether pregnant women can reliably perform SF measurements by themselves. METHOD: Forty healthy women with singleton and ultrasound-dated pregnancies from 2 antenatal clinics in Uppsala, Sweden, were asked to perform 4 consecutive SF measurements once every week, from 20 to 25 weeks of gestation until delivery. The self-administered SF measurements were recorded and systematically compared with midwives' SF measurements. RESULTS: Thirty-three pregnant women performed self-administered SF measurements over a 14-week period (range: 1-21). The SF curves constructed from self-administered SF measurements had the same shape as previously constructed population-based reference curves. The variance for self-administered SF measurements was higher than that of the midwives. CONCLUSIONS: Pregnant women are capable of measuring SF heights by themselves, but with higher individual variance than midwives. Repeated measurements at each occasion can compensate for the higher variance. The main advantage of self-administered SF measurements is the opportunity to follow fetal growth earlier and more frequently. 相似文献
30.
Michael S. Gold Patrick J. Quinn Dianne E. Campbell Jane Peake Joanne Smart Marnie Robinson Michael OSullivan Josef Korbinian Vogt Helle Krogh Pedersen Xiaoqiu Liu Elham Pazirandeh-Micol Ralf G. Heine 《Nutrients》2022,14(11)
This open-label, non-randomized, multicenter trial (Registration: ) aimed to assess if an amino acid-based formula (AAF) supplemented with two human milk oligosaccharides (HMO) supports normal growth and is well tolerated in infants with a cow’s milk protein allergy (CMPA). Term infants aged 1–8 months with moderate-to-severe CMPA were enrolled. The study formula was an AAF supplemented with 2′-fucosyllactose (2′-FL) and lacto-N-neotetraose (LNnT). Infants were fed the study formula for 4 months and were offered to remain on the formula until 12 months of age. Tolerance and safety were assessed throughout the trial. Out of 32 infants (mean age 18.6 weeks; 20 (62.5%) male), 29 completed the trial. During the 4-month principal study period, the mean weight-for-age Z score (WAZ) increased from –0.31 at the baseline to +0.28 at the 4-months’ follow-up. Linear and head growth also progressed along the WHO child growth reference, with a similar small upward trend. The formula was well tolerated and had an excellent safety profile. When comparing the microbiome at the baseline to the subsequent visits, there was a significant on-treatment enrichment in HMO-utilizing bifidobacteria, which was associated with a significant increase in fecal short-chain fatty acids. In addition, we observed a significant reduction in the abundance of fecal Proteobacteria, suggesting that the HMO-supplemented study formula partially corrected the gut microbial dysbiosis in infants with CMPA. NCT 03661736相似文献