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1.
Nuklearmedizin ; 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38387615

RESUMEN

AIM: To investigate the relationship between off-target binding of the amyloid tracer [18F]florbetaben (FBB) in the skull and skull density. METHODS: Forty-three consecutive patients were included retrospectively (age 70.2±7.5y, 42% females, 65% amyloid-positive). For each patient, CT skull density (in Hounsfield units) and (late) FBB uptake in the skull were obtained using an individual skull mask generated by warping the skull tissue probability map provided by the statistical parametric mapping software package (version SPM12) to the native patient space. Skull FBB uptake (mean of the 10% hottest voxels) was scaled to the individual median FBB uptake in the pons. The association between skull FBB uptake and skull density was tested by correlation analyses. Univariate analysis of variance (ANOVA) of skull FBB uptake with dichotomized skull density (low: ≤ median, high), sex (female, male) and amyloid-status (positive, negative) as between-subjects factors was used to assess the impact of sex and amyloid status. RESULTS: There was a significant inverse correlation between skull FBB uptake and skull density (Pearson correlation coefficient -0.518, p < 0.001; Spearman rho -0.321, p = 0.036). The ANOVA confirmed the bone density effect on the FBB uptake in the skull (p = 0.019). In addition, sex (p = 0.012) and density*sex interaction (p = 0.016) had a significant impact. Skull FBB uptake was significantly higher in females with low skull density than for all other combinations of sex and skull density. Amyloid status did not reach statistical significance (p = 0.092). CONCLUSION: Off-target binding of FBB in the skull is inversely associated with skull density. The relationship is mainly driven by females. Amyloid status does not have a major impact on skull FBB binding.

2.
Nat Prod Bioprospect ; 13(1): 19, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37284961

RESUMEN

This study investigates the potential of cannabidiol (CBD), one major cannabinoid of the plant Cannabis sativa, alone and in combination with a terpene-enriched extract from Humulus lupulus ("Hops 1"), on the LPS-response of RAW 264.7 macrophages as an established in vitro model of inflammation. With the present study, we could support earlier findings of the anti-inflammatory potential of CBD, which showed a dose-dependent [0-5 µM] reduction in nitric oxide and tumor necrosis factor-alpha (TNF-α) released by LPS-stimulated RAW 264.7 macrophages. Moreover, we observed an additive anti-inflammatory effect after combined CBD [5 µM] and hops extract [40 µg/mL] treatment. The combination of CBD and Hops 1 showed effects in LPS-stimulated RAW 264.7 cells superior to the single substance treatments and akin to the control hydrocortisone. Furthermore, cellular CBD uptake increased dose-dependently in the presence of terpenes from Hops 1 extract. The anti-inflammatory effect of CBD and its cellular uptake positively correlated with terpene concentration, as indicated by comparison with a hemp extract containing both CBD and terpenes. These findings may contribute to the postulations for the so-called "entourage effect" between cannabinoids and terpenes and support the potential of CBD combined with phytomolecules from a non-cannabinoid source, such as hops, for the treatment of inflammatory diseases.

3.
Fish Physiol Biochem ; 34(2): 103-16, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18649028

RESUMEN

Cold-active burbot (Lota lota (L.)) display reduced food intake during the summer. The impact of temperature on their energy budget was investigated in starved fish in a laboratory setting, simulating summer (20 degrees C) and winter (4 degrees C) conditions, to elucidate the impact of high temperature on burbot metabolism. Metabolic effects in burbot were compared to roach (Rutilus rutilus (L.)), which typically fast in winter. During warm acclimation, starvation (four weeks) resulted in a metabolic depression of oxygen consumption in both species. In roach, metabolic rate decreased by 55% after two weeks of starvation. Burbot, in contrast, displayed an immediate depression of metabolic rate by 50%. In both species, no reductions were observed in the cold. The temperature-induced differences between the metabolic rates at 20 degrees C and 4 degrees C showed a lower thermal sensitivity in burbot (Q (10) = 1.9) compared to roach (Q (10) = 2.7). Notably, for each species, energy consumption during starvation was highest under experimental conditions simulating their natural active periods, respectively. Warm acclimated roach relied mainly on muscle reserves, whereas in cold acclimated burbot, liver metabolic stores made a major contribution to the energy turnover. In cold acclimated roach and warm acclimated burbot, however, starvation apparently reduced swimming activity, resulting in considerable savings of energy reserves. These lower energy expenditures in roach and burbot corresponded to their natural inactive periods. Thus, starvation in burbot caused a lower energy turnover when exposed to high temperatures. These season-dependent adaptations of metabolism represent an advantageous strategy in burbot to manage winter temperature and withstand metabolism-activating summer temperatures, whereas roach metabolism correlates with the seasonal temperature cycle.


Asunto(s)
Cyprinidae/metabolismo , Metabolismo Energético , Métodos de Alimentación , Gadiformes/metabolismo , Temperatura , Aclimatación , Animales , Privación de Alimentos , Consumo de Oxígeno , Estaciones del Año
4.
Physiol Biochem Zool ; 75(2): 123-33, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12024288

RESUMEN

Oxygen consumption (Mo(2)), heartbeat rate and form, and circulating hemolymph oxygen content were measured in relation to temperature in the large Antarctic infaunal bivalve Laternula elliptica. After elevations in temperature from 0 degrees to 3 degrees, 6 degrees, and then 9 degrees C, Mo(2) and heartbeat rate rose to new levels, whereas maximum circulating hemolymph oxygen content fell. At 0 degrees C, Mo(2) was 19.6 micromol O(2) h(-1) for a standard animal of 2-g tissue ash-free dry mass, which equates to a 8.95-g tissue dry-mass or 58.4-g tissue wet-mass animal. Elevation of metabolism following temperature change had acute Q(10) values between 4.1 and 5, whereas acclimated figures declined from 3.4 (between 0 degrees and 3 degrees C) to 2.2 (3 degrees -6 degrees C) and 1.9 (6 degrees -9 degrees C). Heartbeat rate showed no acclimation following temperature elevations, with Q(10) values of 3.9, 3.2, and 4.3, respectively. Circulating hemolymph oxygen content declined from 0 degrees to 3 degrees and 6 degrees C but stayed at a constant Po(2) (73-78 mmHg) and constant proportion ( approximately 50%) of the oxygen content of the ambient water. At 9 degrees C, Mo(2) and heartbeat rate both peaked at values 3.3 times those measured at 0 degrees C, which may indicate aerobic scope in this species. After these peaks, both measures declined rapidly over the ensuing 5 d to the lowest measured in the study, and the bivalves began to die. Hemolymph oxygen content fell dramatically at 9 degrees C to values between 2% and 12% of ambient water O(2) content and had a maximum Po(2) of around 20 mmHg. These data indicate an experimental upper lethal temperature of 9 degrees C and a critical temperature, where a long-term switch to anaerobic metabolism probably occurs, of around 6 degrees C for L. elliptica. Concurrent measures of mitochondrial function in the same species had indicated strong thermal sensitivity in proton leakage costs, and our data support the hypothesis that as temperature rises, mitochondrial maintenance costs rapidly outstrip oxygen supply mechanisms in cold stenothermal marine species.


Asunto(s)
Moluscos/metabolismo , Consumo de Oxígeno , Adaptación Fisiológica , Animales , Regiones Antárticas , Frío , Metabolismo Energético , Frecuencia Cardíaca , Hemolinfa/metabolismo , Cinética , Mitocondrias Musculares/metabolismo , Moluscos/citología , Oxígeno/metabolismo
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