403 research outputs found
Cerebral effects of glucagonâlike peptideâ1 receptor blockade before and after RouxâenâY gastric bypass surgery in obese women: A proofâofâconcept restingâstate functional MRI study
Aim:
To assess the effects of RouxâenâY gastric bypass surgery (RYGB)ârelated changes in glucagonâlike peptideâ1 (GLPâ1) on cerebral restingâstate functioning in obese women.
Materials and Methods:
In nine obese females aged 40â54âyears in the fasted state, we studied the effects of RYGB and GLPâ1 on five a priori selected networks implicated in foodâ and rewardârelated processes as well as environment monitoring (default mode, right frontoparietal, basal ganglia, insula/anterior cingulate and anterior cingulate/orbitofrontal networks).
Results:
Before surgery, GLPâ1 receptor blockade (using exendin9â39) was associated with increased right caudate nucleus (basal ganglia network) and decreased right middle frontal (right frontoparietal network) connectivity compared with placebo. RYGB resulted in decreased right orbitofrontal (insula/anterior cingulate network) connectivity. In the default mode network, after surgery, GLPâ1 receptor blockade had a larger effect on connectivity in this region than GLPâ1 receptor blockade before RYGB (all PFWEâ<â.05). Results remained similar after correction for changes in body weight. Default mode and right frontoparietal network connectivity changes were related to changes in body mass index and food scores after RYGB.
Conclusions:
These findings suggest GLPâ1 involvement in restingâstate networks related to food and reward processes and monitoring of the internal and external environment, pointing to a potential role for GLPâ1âinduced changes in restingâstate connectivity in RYGBâmediated weight loss and appetite control
Polymorphism in the oxytocin promoter region in patients with lactase non-persistence is not related to symptoms
<p>Abstract</p> <p>Background</p> <p>Oxytocin and the oxytocin receptor have been demonstrated in the gastrointestinal (GI) tract and have been shown to exert physiological effects on gut motility. The role for oxytocin in the pathophysiology of GI complaints is unknown. The aim of this study was to examine genetic variations or polymorphism of oxytocin (<it>OXT</it>) and its receptor (<it>OXTR</it>) genes in patients with GI complaints without visible organic abnormalities.</p> <p>Methods</p> <p>Genetic variants in the <it>OXT </it>promoter region, and in the <it>OXTR </it>gene in DNA samples from 131 rigorously evaluated patients with Irritable Bowel Syndrome (IBS), 408 homozygous subjects referred for lactase (LCT-13910 C>T, rs4988235) genotyping, and 299 asymptomatic blood donors were compared. One polymorphism related to the <it>OXT </it>gene (rs6133010 A>G) and 4 related to the <it>OXTR </it>gene (rs1465386 G>T, rs3806675 G>A, rs968389 A>G, rs1042778 G>T) were selected for genotyping using Applied Biosystems 7900 HT allele discrimination assays.</p> <p>Results</p> <p>There were no statistically significant differences in the genotype or allele frequencies in any of the SNPs when IBS patients were compared to healthy controls. Among subjects referred for lactase genotyping, the rs6133010 A>G <it>OXT </it>promoter A/G genotype tended to be more common in the 154 non-persistent (27.3%) subjects than in the 254 lactase persistant (18.1%) subjects and in the healthy controls (19.4%) (p = 0.08). When direct comparing, the A/G genotype was less common in the <it>OXT </it>promoter region in controls (p = 0.09) and in subjects with lactase persistence (p = 0.03) compared to subjects with lactase non-persistence. When healthy controls were viewed according to their own LCT-13910 genotypes, the C/C lactase non-persistent controls had a higher frequency for the <it>OXT </it>promoter A/G genotype than LCT-13910 T/T lactase persistent controls (41.2% vs 13.1%).</p> <p>No significant differences in frequencies of the investigated <it>OXTR </it>SNPs were noted in this study.</p> <p>Conclusion</p> <p>The results suggest that polymorphism in the promoter region of the <it>OXT </it>gene is most common in subjects with lactase non-persistence. This polymorphism may not be related to GI symptoms, as it is related to lactase non-persistence also in healthy controls.</p
Large Mesopelagic Fishes Biomass and Trophic Efficiency in the Open Ocean
With a current estimate of B1,000 million tons, mesopelagic fishes likely dominate the
world total fishes biomass. However, recent acoustic observations show that mesopelagic
fishes biomass could be significantly larger than the current estimate. Here we combine
modelling and a sensitivity analysis of the acoustic observations from the Malaspina 2010
Circumnavigation Expedition to show that the previous estimate needs to be revised to at
least one order of magnitude higher. We show that there is a close relationship between the
open ocean fishes biomass and primary production, and that the energy transfer efficiency
from phytoplankton to mesopelagic fishes in the open ocean is higher than what is typically
assumed. Our results indicate that the role of mesopelagic fishes in oceanic ecosystems and
global ocean biogeochemical cycles needs to be revised as they may be respiring B10% of
the primary production in deep water
Influence of Ecto-Nucleoside Triphosphate Diphosphohydrolase Activity on Trypanosoma cruzi Infectivity and Virulence
The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, an endemic zoonosis present in some countries of South and Central Americas. The World Health Organization estimates that 100 million people are at risk of acquiring this disease. The infection affects mainly muscle tissues in the heart and digestive tract. There are no vaccines or effective treatment, especially in the chronic phase when most patients are diagnosed, which makes a strong case for the development of new drugs to treat the disease. In this work we evaluate a family of proteins called Ecto-Nucleoside-Triphosphate-Diphosphohydrolase (Ecto-NTPDase) as new chemotherapy target to block T. cruzi infection in mammalian cells and in mice. We have used inhibitors and antibodies against this protein and demonstrated that T. cruzi Ecto-NTPDases act as facilitators of infection in mammalian cells and virulence factors in mice model. Two of the drugs used in this study (Suramin and Gadolinium) are currently used for other diseases in humans, supporting the possibility of their use in the treatment of Chagas disease
Conserved genes and pathways in primary human fibroblast strains undergoing replicative and radiation induced senescence
Additional file 3: Figure S3. Regulation of genes of Arrhythmogenic right ventricular cardiomyopathy pathway during senescence induction in HFF strains Genes of the âArrhythmogenic right ventricular cardiomyopathyâ pathway which are significantly up- (green) and down- (red) regulated (log2 fold change >1) during irradiation induced senescence (120Â h after 20Â Gy irradiation) in HFF strains. Orange color signifies genes which are commonly up-regulated during both, irradiation induced and replicative senescence
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