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41.
42.
Urinary pharmacokinetics of betalains following consumption of red beet juice in healthy humans. 总被引:1,自引:0,他引:1
Thomas Frank Florian Conrad Stintzing Reinhold Carle Irmgard Bitsch Daniela Quaas Gabriele Strass Roland Bitsch Michael Netzel 《Pharmacological research》2005,52(4):290-297
The aim of the present pilot study was to characterise the renal elimination of betalains after consumption of red beet juice (RBJ). Six healthy, non-smoking female volunteers were given a single oral dose of either 500 mL of a commercial RBJ containing 362.7 mg of betalains and 500 mL of tap water, respectively, in a sequential manner. Urine was collected in intervals up to 24 h post-dose. Renal excretion of betalains was determined spectrophotometrically and quantified as betanin-equivalents. In addition, the identity of individual compounds was confirmed by HPLC coupled with diode-array detection and positive ion electrospray mass spectrometry, respectively. The amount (mean+/-S.D.) of intact betalains (betanin and isobetanin) recovered in urine was 1001+/-273 microg corresponding to 0.28+/-0.08% of the administered dose. Maximum excretion rates were observed after a median tmax,R of 3.0 h (range 2.5-8.0 h) amounting to 91.7+/-30.1 microg/h. The terminal elimination rate constant (lambdaz) and the corresponding half-life were 0.097+/-0.021 h(-1) and 7.43+/-1.47 h, respectively. Using the lambdaz estimates obtained the expected total betalain amount excreted in urine was 1228+/-291 microg. Based on the results obtained it is assumed that either the bioavailability of the betalains is low or that renal clearance is a minor route of systemic elimination for these compounds. The urinary excretion rates of unmetabolised betalains were fast and appeared to be monoexponential suggesting a one-compartment model. In order to get a more complete picture of the pharmacokinetics and health-promoting properties of red beet betalains, quantitative data on betalain bioavailability should include measurements of unchanged compounds and their corresponding metabolites in plasma, urine and bile. 相似文献
43.
TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) is a reproductive toxicant and endocrine disruptor in nearly all vertebrates; however, the mechanisms by which TCDD alters the reproductive system is not well understood. The zebrafish provides a powerful vertebrate model system to investigate molecular mechanisms by which TCDD affects the reproductive system, but little is known regarding reproductive toxic response of zebrafish following chronic, sublethal exposure to TCDD. Here we investigate the accumulation of TCDD in selected tissues of adult female zebrafish and maternal transfer to offspring following dietary exposure to TCDD (0.08-2.16 ng TCDD/fish/day). TCDD accumulated in tissues of zebrafish in a dose- and time-dependent manner, except for brain. Chronic dietary exposure resulting in the accumulation of 1.1-36 ng/g fish did not induce an overt toxic response or suppress spawning activity. The ovosomatic index was impacted with an accumulation of as little as 0.6 ng/g fish, and 10% of the females showed signs of ovarian necrosis following accumulation of approximately 3 ng/g TCDD. Offspring health was impacted with an accumulation of as little as 1.1 ng/g female; thus the lowest observed effect level (LOEL) for reproductive toxicity in female zebrafish is approximately 0.6-1.1 ng/g fish. Maternal transfer resulted in the accumulation of 0.094-1.2 ng/g, TCDD, which was sufficient to induce the typical endpoints of larval TCDD toxicity, commonly referred to as blue sac syndrome. This study provides the necessary framework to utilize the zebrafish model system for further investigations into the molecular mechanisms by which TCDD exerts its reproductive toxic responses. 相似文献
44.
Saman K. Hashmi Katie Bergstrom Alison A. Bertuch Jenny M. Despotovic Eyal Muscal Fan Xia Weimin Bi Andrea Marcogliese Rosa Diaz 《Pediatric blood & cancer》2019,66(1)
Neutropenia in pediatric patients can be due to a variety of disorders. We describe two patients who underwent extensive evaluation over many years for arthralgias and moderate neutropenia of unclear etiology. Genetic testing identified a pathogenic variant in PSTPIP1 (proline‐serine‐threonine phosphatase‐interacting protein 1) in both patients. Markedly elevated inflammatory markers and zinc levels confirmed the rare diagnosis of PSTPIP1‐associated myeloid‐related proteinemia inflammatory (PAMI) syndrome, tailoring treatment. Neutropenia is common in patients with PAMI syndrome. Unique mutations seen in PAMI syndrome may account for the specific phenotypic features of this disorder. 相似文献
45.
M. Rosaria Galanti Lisbeth Hansson Reinhold Bergström Alicja Wolk Anette Hjartåker Eiliv Lund Lars Grimelius Anders Ekbom 《Cancer causes & control : CCC》1997,8(2):205-214
A population-based case-control study was conducted in two regions ofSweden and Norway to investigate the association between dietary habits andthe risk of thyroid cancer. The consumption of selected foods was reported ina self-completed food-frequency questionnaire by 246 cases withhistologically confirmed papillary (n = 209) and follicular (n = 37) thyroidcarcinoma, and 440 age- and gender-matched controls. Odds ratios (OR) andtheir 95 percent confidence interval (CI) were calculated as estimates of therelative risk using conditional logistic regression. High consumption ofbutter (OR = 1.6, CI = 1.1-2.5) and cheese (OR = 1.5, CI = 1.0-2.4) wasassociated with increased risks. Residence in areas of endemic goiter inSweden was associated with an elevated risk, especially among women (OR =2.5, CI = 1.3-4.9). High consumption of cruciferous vegetables was associatedwith increased risk only in persons who ever lived in such areas. A decreasedrisk was associated with consumption of iodized salt in northern Norway, andwith use of iodized salt during adolescence among women (OR = 0.6, CI =0.6-1.0). The results of this study suggest a role of diet and environment inthe risk of thyroid cancer. 相似文献
46.
Immunotherapy of metastatic renal cell carcinoma with tumor lysate-pulsed autologous dendritic cells. 总被引:34,自引:0,他引:34
Lorenz H?ltl Claudia Zelle-Rieser Hubert Gander Christine Papesh Reinhold Ramoner Georg Bartsch Hermann Rogatsch Adel L Barsoum Joseph H Coggin Martin Thurnher 《Clinical cancer research》2002,8(11):3369-3376
PURPOSE: We wanted to evaluate feasibility and safety of dendritic cell-based immunotherapy in patients with metastatic renal cell carcinoma (RCC). EXPERIMENTAL DESIGN: Patients with metastatic RCC (n = 35) received vaccinations (i.v. or i.d.) of CD83+ autologous monocyte-derived dendritic cells (moDCs). MoDCs were loaded with lysate of cultured autologous or allogeneic permanent tumor cells (A-498) as well as keyhole limpet hemocyanin as control and helper antigen. Maturation of moDCs was induced by a combination of tumor necrosis factor alpha, interleukin 1 beta, interleukin 6, and prostaglandin E2. RESULTS: Treatment was associated with transient flu-like symptoms. In 2 of 27 evaluable patients, any evidence of disease disappeared (complete response). In both cases, metastatic tissue had been the source of tumor antigen. One patient had an objective partial response. Seven patients had stable disease, the remaining 17 patients had progressive disease. In 11 of 11 patients evaluated, moDCs induced strong immune responses against keyhole limpet hemocyanin. In 5 of 6 patients tested, enhanced immune responses against oncofetal antigen (immature laminin receptor; OFA/LRP) could also be detected. The strongest responses against OFA/LRP were detectable in 2 patients with complete response and partial response, respectively. At the time of submission, mean follow up is 32 months and 8 patients are currently alive. CONCLUSIONS: Our data indicate that moDC-based vaccination is well tolerated and has immunological as well as clinical effects in patients with metastatic RCC. OFA/LRP might be an attractive candidate antigen for DC-based immunotherapy of RCC. 相似文献
47.
Greta Walz Nicola Blazynski Lukas Frey Katja Schneider-Momm Hans-Willi Clement Reinhold Rauh Eberhard Schulz Monica Biscaldi Christina Clement Christian Fleischhaker 《Nutrients》2022,14(23)
In the early 1920s, it was discovered that nutrition is associated with what is known today as Attention-Deficit/Hyperactivity Disorder (ADHD) and that certain foods can worsen the symptoms. In previous studies, approximately 60% of the participants experience at least a 40% reduction in ADHD symptoms after an oligoantigenic diet (OD). The purpose of this study was to evaluate ADHD symptoms in children approximately 3.5 years after completing a 4-week oligoantigenic diet. Among 28 participants who completed the 4-week diet, 21 were re-assessed for this study after 3.5 years. The severity of ADHD symptoms was assessed with the ADHD-Rating-Scale-IV (ARS). Of 21 participants, 14 fulfilled the responder criterion, whereas 7 did not. At follow-up, 28% of the participants were taking medication. The mean ARS total score improved significantly from T1: M = 29.62 (SD = 9.80) to T2: M = 15.86 (SD = 8.56) between the time points before and after the diet (d = −1.91). There was also a lower ARS total score at the follow-up T5: M = 16.00 (SD = 10.52) compared to before the diet (d = −1.17). This study shows that individually adjusted nutrition significantly improved the ADHD symptomatology of the participants long-term. This suggests that an oligoantigenic diet with subsequent individual nutritional recommendations could become an additional treatment option for children with ADHD. 相似文献
48.
The putatively selective D-1 dopamine receptor antagonist SCH 23390 was used to study the role of the D-1 dopamine receptor in mediating the pre- and postsynaptic effects of dopamine agonists in the basal ganglia. SCH 23390 (1 mg/kg) had no significant effect on the tonic activity of substantia nigra dopamine neurons in 47% of the 19 cells studied, while the firing rates of 53% of the cells were increased. SCH 23390 did not shift the dose response of these cells to apomorphine, whereas the selective D-2 antagonist, YM-09151-2 completely blocked apomorphine's inhibitory effects on nigral dopamine cell activity. These results suggest that SCH 23390 does not interact with the D-2 dopamine autoreceptors, but does excite a subpopulation of dopamine neurons presumably through postsynaptic actions. In contrast to its inability to modify the effects of apomorphine on dopamine autoreceptors, SCH 23390 partially to fully reversed the effects of apomorphine on globus pallidus and substantia nigra pars reticulata cell activity and significantly attenuated the effects of apomorphine, pergolide, quinpirole (LY 171555) and d-amphetamine on firing rates of globus pallidus neurons. The D-1 antagonist alone had no significant effect on tonic globus pallidus neuronal activity. SCH 23390 was more potent than haloperidol in its ability to attenuate the effects of apomorphine on pallidal activity, but unlike haloperidol, was unable to totally inhibit these effects, suggesting that the two antagonists block the excitatory effects of apomorphine on pallidal cell firing rates by different mechanisms. The serotonin2 receptor antagonist, ketanserin, had no effect on pallidal or dopamine cell activity, indicating that the effects of SCH 23390 were not mediated through interactions with serotonin2 receptors. These results suggest that D-1 receptor blockade attenuates the postsynaptic, but not autoreceptor-mediated effects of dopamine agonists. 相似文献
49.
50.
Dynamic enhancement of upper abdominal organs in normal volunteers with MRI and effects of contrast dose reduction 总被引:3,自引:0,他引:3
Background: To quantify enhancement parameters of the upper abdominal organs over time during magnetic resonance (MR) examinations and
to evaluate the effect of a dose reduction of contrast medium on these parameters.
Methods: Ten volunteers underwent two separate dynamic enhanced MR examinations with 0.1 and 0.075 mmol/kg of contrast medium, respectively.
Breath-hold gradient-echo T1-weighted images were acquired every second for 118 s followed by delayed images. The percentages
of enhancement, the time to maximum enhancement, and the area under the time-versus-enhancement curve were calculated for
each organ.
Results: The mean times to maximum percentage of enhancement were less than 25 s for the pancreas, kidneys, and spleen and 50 s for
the liver. The mean values of maximum percentage of enhancement for the standard/reduced doses were 72%/62% (pancreas), 165%/155%
(kidneys), 114%/87% (spleen), and 67%/53% (liver). This difference was significant when liver enhancement was considered (p= 0.02). In addition, when the areas under the time-versus-enhancement curves were compared, the difference between the standard
dose and reduced dose was significant for all organs tested (p < 0.05).
Conclusions: Dynamic scanning of the upper abdomen should start early after contrast injection. Injection parameters should be standardized
to capture arterial and venous enhancements in liver examinations. A 25% dose reduction did not significantly affect peak
enhancement (except for the liver) but did significantly reduce overall enhancement.
Received: 8 September 1998/Revision accepted: 13 January 1999 相似文献