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201.
Alvheim AR Malde MK Osei-Hyiaman D Hong Lin Y Pawlosky RJ Madsen L Kristiansen K Frøyland L Hibbeln JR 《Obesity (Silver Spring, Md.)》2012,20(10):1984-1994
Suppressing hyperactive endocannabinoid tone is a critical target for reducing obesity. The backbone of both endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA) is the ω-6 fatty acid arachidonic acid (AA). Here we posited that excessive dietary intake of linoleic acid (LA), the precursor of AA, would induce endocannabinoid hyperactivity and promote obesity. LA was isolated as an independent variable to reflect the dietary increase in LA from 1 percent of energy (en%) to 8 en% occurring in the United States during the 20th century. Mice were fed diets containing 1 en% LA, 8 en% LA, and 8 en% LA + 1 en% eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) in medium-fat diets (35 en% fat) and high-fat diets (60 en%) for 14 weeks from weaning. Increasing LA from 1 en% to 8 en% elevated AA-phospholipids (PL) in liver and erythrocytes, tripled 2-AG + 1-AG and AEA associated with increased food intake, feed efficiency, and adiposity in mice. Reducing AA-PL by adding 1 en% long-chain ω-3 fats to 8 en% LA diets resulted in metabolic patterns resembling 1 en% LA diets. Selectively reducing LA to 1 en% reversed the obesogenic properties of a 60 en% fat diet. These animal diets modeled 20th century increases of human LA consumption, changes that closely correlate with increasing prevalence rates of obesity. In summary, dietary LA increased tissue AA, and subsequently elevated 2-AG + 1-AG and AEA resulting in the development of diet-induced obesity. The adipogenic effect of LA can be prevented by consuming sufficient EPA and DHA to reduce the AA-PL pool and normalize endocannabinoid tone. 相似文献
202.
Among postmenopausal women, declining estrogen may facilitate fat partitioning from the periphery to the intra-abdominal space. Furthermore, it has been suggested that excess androgens contribute to a central fat distribution pattern in women. The objective of this longitudinal study was to identify independent associations of the hormone milieu with fat distribution in postmenopausal women. Fifty-three healthy postmenopausal women, either using or not using hormone replacement therapy (HRT) were evaluated at baseline and 2 years. The main outcomes were intra-abdominal adipose tissue (IAAT), subcutaneous abdominal adipose tissue, and total thigh fat analyzed by computed tomography scanning and leg fat and total body fat mass measured by dual-energy X-ray absorptiometry. Serum estradiol, estrone, estrone sulfate, total testosterone, free testosterone, androstenedione, dehydroepiandrosterone sulfate), sex hormone-binding globulin (SHBG), and cortisol were assessed. On average, in all women combined, IAAT increased by 10% (10.5 cm(2)) over 2 years (P < 0.05). Among HRT users, estradiol was inversely associated with, and estrone was positively associated with, 2-year gain in IAAT. Among HRT nonusers, free testosterone was inversely associated with, and SHBG was positively associated with, 2-year gain in IAAT. These results suggest that in postmenopausal women using HRT, greater circulating estradiol may play an integral role in limiting lipid deposition to the intra-abdominal cavity, a depot associated with metabolically detrimental attributes. However, a high proportion of weak estrogens may promote fat partitioning to the intra-abdominal cavity over time. Furthermore, among postmenopausal women not using HRT, greater circulating free testosterone may limit IAAT accrual. 相似文献
203.
Elisa Alonso-Perez Marian Suarez-Gestal Manuel Calaza Gian Domenico Sebastiani Rudolf Pullmann Chryssa Papasteriades Attila Kovacs Fotini N Skopouli Marc Bijl Ana Suarez Maurizio Marchini Sergio Migliaresi Patricia Carreira Josep Ordi-Ros Torsten Witte Sarka Ruzickova Maria Jose Santos Nadia Barizzone Francisco J Blanco Bernard R Lauwerys Juan J Gomez-Reino Antonio Gonzalez 《Arthritis research & therapy》2012,14(2):1-13
Introduction
Prevalence of an abnormal Papanicolaou smear was significantly increased in lupus patients in cross-sectional studies, associated with a higher prevalence of high-risk human papillomavirus (HPV) infection. The nucleic acid-specific Toll-like receptors (TLRs) locate at the endolysosomal compartments and trigger the induction of cytokines for the innate immune response. This study evaluated whether abnormal host innate immune response in lupus patients may enhance HPV persistence.Methods
Protein levels of TLRs 3, 7, 8 and 9 in cervical epithelial cells of lupus patients and controls with or without HPV infection were assessed using flow cytometry. Characteristics associated with the differential expression of TLRs in systemic lupus erythematosus (SLE) were elucidated. The effect and interferon-stimulated genes (ISGs) (ISG15 and Mx-1) gene expressions were then measured in oncogenic HeLa (HPV18), CaSki (HPV) and C33A (HPV negative) cell lines using flow cytometry and quantitative real-time PCR. Ex vivo productions of cytokines and interferon-gamma (IFN-??) upon TLR ligands stimulations were subsequently measured using cytometric bead array and ELISA.Results
For subjects with HPV infection, levels of TLR3 and TLR7 were significantly lower in lupus patients compared with controls. Significantly decreased TLRs 7, 8 and 9 levels were observed in HPV-negative SLE compared to healthy controls. For SLE with and without HPV infection, TLR7 and 9 levels were significantly lower in infected SLE than those in HPV-negative patients. Independent explanatory variables associated with down-regulation of TLR7 level included HPV infection and a higher cumulative dose of prednisolone; while a higher cumulative dose of hydroxychloroquine and HPV infection were associated with down-regulation of TLR9 level. In cervical cell lines, TLRs 3, 7, 8, 9 protein levels and antiviral ISG15 and Mx-1 gene expressions were inhibited in two oncogenic HPV types. Functional data showed that the induction of pro-inflammatory cytokines by TLR ligands (R837, ssRNA and ODN2395) was greatly impaired in CaSki and HeLa than C33A cells.Conclusions
In conclusion, prednisolone and TLR antagonist (hydroxychloroquine) may down-regulate protein levels of TLR7 and TLR9 in lupus patients, thereby decreasing the innate immune response against HPV infection. Upon infection, HPV further down-regulate TLR7 and 9 levels for viral persistence. Furthermore, reduction of nucleic acid-sensing TLRs 7, 8 and 9 in carcinogenic HPVs ensures that the expression of inducible pro-inflammatory cytokines is minimized to prevent the expression of antiviral ISGs (ISG15 and Mx-1) on a biologically relevant antiviral response. 相似文献204.
Igor Sirák Marian Kacerovský Miroslav Hodek Jiří Petera Jiří Špaček Linda Kašaová Zdeněk Zoul Milan Vošmik 《Reports of Practical Oncology and Radiotherapy》2012,17(1):19-23
Background/AimTo evaluate whether non-closure of the visceral peritoneum after total abdominal hysterectomy (TAH) and bilateral salpingo-oophorectomy (BSO) in patients with uterine corpus carcinoma influences the volume of the small intestine within the irradiated volume during adjuvant radiotherapy or late radiation intestinal toxicity.Materials and methodsA total of 152 patients after TAH + BSO with adjuvant pelvic radiotherapy were studied. The state of peritonealization was retrospectively evaluated based on surgical protocols. The volume of irradiated bowels was calculated by CT-based delineation in a radiotherapy planning system. The influence of visceral peritonealization upon the volume of the small intestine within the irradiated volume and consequent late morbidity was analyzed.ResultsVisceral peritonealization was not performed in 70 (46%) of 152 studied patients. The state of peritonealization did not affect the volume of the irradiated small intestine (p = 0.14). Mean volume of bowels irradiated in patients with peritonealization was 488 cm3 (range 200–840 cm3, median 469 cm3); mean volume of bowels irradiated in patients without peritonealization was 456 cm3 (range 254–869 cm3, median 428 cm3). We did not prove any significant difference between both arms. Nor did we observe any influence of non-peritonealization upon late intestinal morbidity (p = 0.34).ConclusionNon-closure of the visceral peritoneum after hysterectomy for uterine corpus carcinoma does not increase the volume of the small intestine within the irradiated volume, with no consequent intestinal morbidity enhancement. 相似文献
205.
Elisa Alonso-Perez Marian Suarez-Gestal Manuel Calaza Gian Domenico Sebastiani Rudolf Pullmann Chryssa Papasteriades Attila Kovacs Fotini N Skopouli Marc Bijl Ana Suarez Maurizio Marchini Sergio Migliaresi Patricia Carreira Josep Ordi-Ros Torsten Witte Sarka Ruzickova Maria Jose Santos Nadia Barizzone Francisco J Blanco Bernard R Lauwerys Juan J Gomez-Reino Antonio Gonzalez 《Arthritis research & therapy》2012,14(2):R94
Introduction
We aimed to investigate whether the effect size of the systemic lupus erythematosus (SLE) risk alleles varies across European subpopulations.Methods
European SLE patients (n = 1,742) and ethnically matched healthy controls (n = 2,101) were recruited at 17 centres from 10 different countries. Only individuals with self-reported ancestry from the country of origin were included. In addition, participants were genotyped for top ancestry informative markers and for 25 SLE associated SNPs. The results were used to compare effect sizes between the Central Eureopan and Southern European subgroups.Results
Twenty of the 25 SNPs showed independent association with SLE, These SNPs showed a significant bias to larger effect sizes in the Southern subgroup, with 15/20 showing this trend (P = 0.019) and a larger mean odds ratio of the 20 SNPs (1.46 vs. 1.34, P = 0.02) as well as a larger difference in the number of risk alleles (2.06 vs. 1.63, P = 0.027) between SLE patients and controls than for Central Europeans. This bias was reflected in a very significant difference in the cumulative genetic risk score (4.31 vs. 3.48, P = 1.8 × 10-32). Effect size bias was accompanied by a lower number of SLE risk alleles in the Southern subjects, both patients and controls, the difference being more marked between the controls (P = 1.1 × 10-8) than between the Southern and Central European patients (P = 0.016). Seven of these SNPs showed significant allele frequency clines.Conclusion
Our findings showed a bias to larger effect sizes of SLE loci in the Southern Europeans relative to the Central Europeans together with clines of SLE risk allele frequencies. These results indicate the need to study risk allele clines and the implications of the polygenic model of inheritance in SLE. 相似文献206.
207.
208.
209.
Cercomonads are important components of microbial food webs in soils and aquatic sediments. Here, we investigated the general morphology, behaviour, life cycle and 18S rDNA phylogeny of cercomonad cultures from a German grassland soil habitat. We describe ten new species including two new genera from 23 strains. Three Cercomonas, two Eocercomonas and three Paracercomonas species are described. Based on large phylogenetic distance and distinct morphology, we erect two novel clade B genera near the root of the cercomonad tree. Nucleocercomonas nov. gen. bears a number of characters unusual for cercomonads: Its anterior flagellum is extremely long, it mostly does not glide, and in its most frequent life stage the cell body does not attach to the substratum, but produces unattached pseudopodia. Furthermore, it has a unique nucleus with a peripheral nucleolus that attaches to the nuclear envelope opposite the basal body connection. Metabolomonas nov. gen. is extremely metabolic. It is characterized by a very high beating frequency of the anterior flagellum, fast gliding, rapid changes in shape and strong cytoplasmic streams. A new genus Brevimastigomonas is erected for the previously described species Paracercomonas anaerobica. The general morphology of cercomonad species often does not correspond with their phylogenetic position: closely related species may have a very different morphology. 相似文献
210.
Garne E Loane M Dolk H Barisic I Addor MC Arriola L Bakker M Calzolari E Matias Dias C Doray B Gatt M Melve KK Nelen V O'Mahony M Pierini A Randrianaivo-Ranjatoelina H Rankin J Rissmann A Tucker D Verellun-Dumoulin C Wiesel A 《Birth defects research. Part A, Clinical and molecular teratology》2012,94(3):134-140