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1.
Because of their physiological similarity to humans, pigs provide an excellent model for the study of obesity. This study evaluated diet-induced adiposity in genetically lean pigs and found that body weight and energy intake did not differ between controls and pigs fed the high-fat (HF) diet for three months. However, fat mass percentage, adipocyte size, concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), insulin, and leptin in plasma were significantly higher in HF pigs than in controls. The HF diet increased the expression in backfat tissue of genes responsible for cholesterol synthesis such as Insig-1 and Insig-2. Lipid metabolism-related genes including sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase 1 (FASN1), diacylglycerol O-acyltransferase 2 (DGAT2), and fatty acid binding protein 4 (FABP4) were significantly up-regulated in backfat tissue, while the expression of proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase 2 (CPT2), both involved in fatty acid oxidation, was reduced. In liver tissue, HF feeding significantly elevated the expression of SREBP-1c, FASN1, DGAT2, and hepatocyte nuclear factor-4α (HNF-4α) mRNAs. Microarray analysis further showed that the HF diet had a significant effect on the expression of 576 genes. Among these, 108 genes were related to 21 pathways, with 20 genes involved in adiposity deposition and 26 related to immune response. Our results suggest that an HF diet can induce genetically lean pigs into obesity with body fat mass expansion and adipose-related inflammation.  相似文献   

2.
Intramuscular fat (IMF) is a crucial factor in the quality of chicken meat. The genetic basis underlying it is complex. Follicle-stimulating hormone (FSH), well-known as an effector in reproductive tissues, was recently discovered to stimulate abdominal fat accumulation in chicken. The effect of FSH on IMF accumulation and the underlying molecular regulatory mechanisms controlling both IMF and abdominal fat deposition in vivo are largely unknown. In this study, two groups of chickens were treated with chicken FSH or a placebo. The lipid content of breast muscle, abdominal fat volume, and serum concentrations of FSH were examined. Related genes implicated in breast muscle and abdominal fat accumulation were also investigated. Compared to the control group, the triglyceride (TG) content of breast muscle and the percentage of abdominal fat in FSH-treated chickens were significantly increased by 64.9% and 56.5% (P<0.01), respectively. The FSH content in the serum of FSH-treated chickens was 2.1 times than that of control chickens (P<0.01). Results from quantitative real-time polymerase chain reaction (qRT-PCR) assays showed that relative expression levels of fatty acid synthase (FAS), lipoprotein lipase (LPL), diacylglycerol acyltransferase 2 (DGAT2), adipocyte fatty acid binding protein (A-FABP), and peroxisome proliferator-activated receptor γ (PPARγ) were significantly upregulated in breast muscle following FSH treatment (P<0.01). Treatment with FSH also significantly increased relative expression levels of FAS, LPL, DGAT2, A-FABP, and PPARγ in abdominal fat tissue (P<0.05). The results of principal component analysis (PCA) for gene expression (breast muscle and abdominal fat) showed that the control and FSH treatment groups were well separated, which indicated the reliability of the data. This study demonstrates that FSH plays an important role in IMF accumulation in female chickens, which likely involves the regulation of biosynthesis genes related to lipid metabolism.  相似文献   

3.

Objective

Being overweight or obese comprises a significant risk factor for atherosclerosis. Fat tissue also generates factors stimulating angiogenesis, the process by which new blood vessels form. The purpose of this paper is to assess concentrations of the vascular endothelial growth factor A (VEGF-A) and its soluble type-1 and type-2 receptors (sVEGFR-1 and sVEGFR-2) in plasma of patients with peripheral arterial disease (PAD) depending on the level of nutrition according to body mass index (BMI).

Methods

The study group included patients suffering from symptomatic PAD (n=46) in Fontaine classes IIa–IV without any history of neoplastic disease and who have a normal BMI (n=15), are overweight (n=21) or are obese (n=10). The control group (n=30) consisted of healthy non-smoking volunteers who were neither overweight nor obese. Venous blood plasma samples were collected from both groups at rest in the morning to determine plasma concentrations of VEGF-A, sVEGFR-1, and sVEGFR-2 using the enzymelinked immunosorbent assay (ELISA) method.

Results

The group of patients with PAD co-existent with being overweight or obese tended to have higher mean concentration levels of VEGF-A and sVEGFR-2 when compared with patients suffering from PAD with normal BMI. A statistically significant positive correlation was obtained between BMI and average plasma concentrations of sVEGFR-2 (R=0.37, P=0.0103). However, no significant correlation was noticed between BMI and VEGF-A or sVEGFR-1 concentrations.

Conclusions

A positive correlation determined between the level of antiangiogenic factor and BMI value may be indicative of the linearly growing prevalence of some antiangiogenic factors in patients with metabolic disorders, which may be one of numerous factors contributing to incomplete efficiency of collateral circulation development in patients with PAD.
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4.
We have investigated comprehensively the effects of thyroid function on gallstone formation in a mouse model. Gonadectomized gallstone-susceptible male C57BL/6 mice were randomly distributed into three groups each of which received an intervention to induce hyperthyroidism, hypothyroidism, or euthyroidism. After 5 weeks of feeding a lithogenic diet of 15% (w/w) butter fat, 1% (w/w) cholesterol, and 0.5% (w/w) cholic acid, mice were killed for further experiments. The incidence of cholesterol monohydrate crystal formation was 100% in mice with hyperthyroidism, 83% in hypothyroidism, and 33% in euthyroidism, the differences being statistically significant. Among the hepatic lithogenic genes, Trβ was found to be up-regulated and Rxr down-regulated in the mice with hypothyroidism. In contrast, Lxrα, Rxr, and Cyp7α1 were up-regulated and Fxr down-regulated in the mice with hyperthyroidism. In conclusion, thyroid dysfunction, either hyperthyroidism or hypothyroidism, promotes the formation of cholesterol gallstones in C57BL/6 mice. Gene expression differences suggest that thyroid hormone disturbance leads to gallstone formation in different ways. Hyperthyroidism induces cholesterol gallstone formation by regulating expression of the hepatic nuclear receptor genes such as Lxrα and Rxr, which are significant in cholesterol metabolism pathways. However, hypothyroidism induces cholesterol gallstone formation by promoting cholesterol biosynthesis.  相似文献   

5.
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6.
It is widely accepted that body weight and adipose mass are tightly regulated by homeostatic mechanisms, in which leptin plays a critical role through hypothalamic pathways, and obesity is a result of homeostatic disorder. However, in C57BL/6J mice, we found that Rcan2 increases food intake and plays an important role in the development of age- and diet-induced obesity through a leptin-independent mechanism. RCAN2 was initially identified as a thyroid hormone (T3)-responsive gene in human fibroblasts. Expression of RCAN2 is regulated by T3 through the PI3K-Akt/PKB-mTOR-Rps6kb1 signaling pathway. Intriguingly, both Rcan2?/? and Rps6kb1?/? mutations were reported to result in lean phenotypes in mice. In this study we compared the effects of these two mutations on growth and body weight in C57BL/6J mice. We observed reduced body weight and lower fat mass in both Rcan2?/? and Rps6kb1?/? mice compared to the wild-type mice, and we reported other differences unique to either the Rcan2?/? or Rps6kb1?/? mice. Firstly, loss of Rcan2 does not directly alter body length; however, Rcan2?/? mice exhibit reduced food intake. In contrast, Rps6kb1?/? mice exhibit abnormal embryonic development, which leads to smaller body size and reduced food intake in adulthood. Secondly, when fed a normal chow diet, Rcan2?/? mice weigh significantly more than Rps6kb1?/? mice, but both Rcan2?/? and Rps6kb1?/? mice develop similar amounts of epididymal fat. On a high-fat diet, Rcan2?/? mice gain body weight and fat mass at slower rates than Rps6kb1?/? mice. Finally, using the double-knockout mice (Rcan2?/?Rps6kb1?/?), we demonstrate that concurrent loss of Rcan2 and Rps6kb1 has an additive effect on body weight reduction in C57BL/6J mice. Our data suggest that Rcan2 and Rps6kb1 mutations both affect growth and body weight of mice, though likely through different mechanisms.  相似文献   

7.
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8.
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9.
In plants, lipoxygenases (LOXs) play a crucial role in biotic and abiotic stresses. In our previous study, five 13-LOX genes of oriental melon were regulated by abiotic stress but it is unclear whether the 9-LOX is involved in biotic and abiotic stresses. The promoter analysis revealed that CmLOX09 (type of 9-LOX) has hormone elements, signal substances, and stress elements. We analyzed the expression of CmLOX09 and its downstream genes—CmHPL and CmAOS—in the leaves of four-leaf stage seedlings of the oriental melon cultivar “Yumeiren” under wound, hormone, and signal substances. CmLOX09, CmHPL, and CmAOS were all induced by wounding. CmLOX09 was induced by auxin (indole acetic acid, IAA) and gibberellins (GA3); however, CmHPL and CmAOS showed differential responses to IAA and GA3. CmLOX09, CmHPL, and CmAOS were all induced by hydrogen peroxide (H2O2) and methyl jasmonate (MeJA), while being inhibited by abscisic acid (ABA) and salicylic acid (SA). CmLOX09, CmHPL, and CmAOS were all induced by the powdery mildew pathogen Podosphaera xanthii. The content of 2-hexynol and 2-hexenal in leaves after MeJA treatment was significantly higher than that in the control. After infection with P. xanthii, the diseased leaves of the oriental melon were divided into four levels—levels 1, 2, 3, and 4. The content of jasmonic acid (JA) in the leaves of levels 1 and 3 was significantly higher than that in the level 0 leaves. In summary, the results suggested that CmLOX09 might play a positive role in the response to MeJA through the hydroperoxide lyase (HPL) pathway to produce C6 alcohols and aldehydes, and in the response to P. xanthii through the allene oxide synthase (AOS) pathway to form JA.  相似文献   

10.
This study was conducted to investigate the effects of fresh fermented soybean meal (FSM) on the growth performance of nursery piglets, nitrogen excretion in feces, and the concentrations of ammonia (NH3) and particulate matter (PM) in the piggery. A total of 472 nursery piglets (Landrace×Yorkshire, (16.3±0.36) kg body weight) were randomly allocated into two treatments with 236 pigs in each treatment. The pigs were fed the basal diet without fresh FSM (control) or diet containing 10% (100 g/kg) fresh FSM (FSM group), and the crude protein content of the two groups was consistent. The feeding trial lasted for 28 d. The results showed that the pigs fed fresh FSM had increased (P<0.05) average daily gain (ADG) compared with the control. There was no significant difference (P>0.05) in feed to gain ratio (F:G) between the two groups. During the whole experiment, the concentration of NH3 in the piggery decreased (P<0.05) by 19.0%, and the concentrations of PM (PM10 and PM2.5) in the piggery decreased (P<0.05) by 19.9% and 11.6%, respectively, in the FSM group, compared with the control. The ammonia nitrogen and nitrite content in feces increased (P<0.05) by 32.9% and 28.4%, respectively, in the FSM group. The fecal pH declined (P<0.05) significantly in the FSM group compared with the control. At the end of experiment, total protein (TP) concentration was increased (P<0.05) significantly and blood urea nitrogen (BUN) concentration was decreased (P<0.05) for pigs fed the diet with fresh FSM. The results indicated that dietary fresh FSM not only improved the growth performance of nursery piglets, but also reduced the NH3 concentration in the piggery due to nitrogen conversion, and decreased the concentrations of PM10 and PM2.5 in the piggery.  相似文献   

11.
As an easy application of the intermediate value theorem, one can show that for any continuous function f: [0, 1] → ? with f (0) = f (1), there are points a, a + 1/2 both in [0, 1] such that f (a) = f (a + 1/2). In this note, we show that this property holds with 1/2 replaced by any number of the form 1/n for a positive integer n. More interestingly, we show that this is false for every number not of the form 1/n.  相似文献   

12.
To address the need for effective, efficient ways to apply active learning in undergraduate biology courses, in this paper, we propose a problem-centered approach that utilizes supplemental web-based instructional materials based on principles of active learning. We compared two supplementary web-based modules using active learning strategies: the first used Merrill’s First Principles of Instruction as a framework for organizing multiple active learning strategies; the second used a traditional web-based approach. Results indicated that (a) the First Principles group gained significantly from pretest to posttest at the Remember level (t(40) = ?1.432, p = 0.08, ES = 0.4) and at the Problem Solving level (U = 142.5, N1 = 21, N2 = 21, p = .02, ES = 0.7) and (b) the Traditional group gained significantly from pretest to posttest at the Remember level (t(36) = 1.762, p = 0.043, ES = 0.6). Those in the First Principles group were significantly more likely than the traditional group to be confident in their ability to solve problems in the future (χ2 (2, N = 40) = 3.585, p = 0.09).  相似文献   

13.

Background

Coronary heart disease (CHD) is characterized by arterial wall inflammation and matrix degradation. Matrix metalloproteinase (MMP)-22 and -29 and pro-inflammatory cytokine interleukin-18 (IL18) are present in human hearts. IL18 may regulate MMP-22 and -29 expression, which may correlate with CHD progression.

Methods and results

Immunoblot analysis showed that IL18 induced MMP-22 expression in human aortic smooth muscle cells. The Mann Whitney test from a prospective study of 194 CHD patients and 68 non-CHD controls demonstrated higher plasma levels of IL18, MMP-22 and -29 in CHD patients than in the controls. A logistic regression test suggested that plasma IL18 (odds ratio (OR)=1.131, P=0.007), MMP-22 (OR=1.213, P=0.040), and MMP-29 (OR=1.198, P=0.033) were independent risk factors of CHD. Pearson’s correlation test showed that IL18 (coefficient (r)=0.214, P=0.045; r=0.246, P=0.031) and MMP-22 (r=0.273, P=0.006; r=0.286, P=0.012) were associated with the Gensini score before and after adjusting for potential confounding factors. The multivariate Pearson’s correlation test showed that plasma MMP-22 levels correlated positively with high-sensitive-C-reactive protein (hs-CRP) (r=0.167, P=0.023), and MMP-29 levels correlated negatively with triglyceride (r=?0.169, P=0.018). Spearman’s correlation test indicated that plasma IL18 levels associated positively with plasma MMP-22 (r=0.845, P<0.001) and MMP-29 (r=0.548, P<0.001).

Conclusions

Our observations suggest that IL18, MMP-22 and -29 serve as biomarkers and independent risk factors of CHD. Increased systemic IL18 in CHD patients may contribute to elevated plasma MMP-22 and -29 levels in these patients.
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14.

Objective

The aim of this study was to explore the association of dopamine receptor D2 (DRD2) polymorphism and alleviation of obesity in children and adolescents after 8-year follow-up.

Methods

This retrospective cohort study included obese children and adolescents with a follow-up period of 8 years. Baseline clinical characteristics and DRD2 polymorphisms (including rs1076562, rs2075654, and rs4586205) were extracted from medical records. A follow-up visit was performed in May 2017 to collect related data including height, weight, diet compliance, and exercise compliance.

Results

One hundred and nine obese children and adolescents were included in the current study. Among three DRD2 single nucleotide polymorphisms, only rs2075654 had a statistically significant association with alleviation of obesity, as the alleviation rate for minor allele carriers (68.6% for TC+TT) was higher compared to the major allele homozygote (43.3% for CC). After adjusting for all related factors, the hazard ratio of rs2075654 minor allele carriers for the alleviation of obesity was 3.34 (95% confidence interval (CI): 1.30?8.58).

Conclusions

The rs2075654 polymorphism of DRD2 is related to long-term obesity alleviation in obese Chinese children and adolescents.
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15.
1　Introduction　AmatrixA∈Cn×missaidtobecentrohermitianifA =Jn AJm,andskewcentrohermitianifA =-Jn AJm,where Adenotetheconjugateofthema trixAandJlisthepermutationmatrixoforderlwithonesonthecrossdiagonal(bottomlefttotopright)andzeroselsewhere .ThehermitianToeplitzmatricesformanimportantsubclassofcentrohermi tianmatriceswhichoccurnaturallyindigitalsignalprocessingandotherareas ,seeforinstance[1] andreferencetherein .Thecentrohermitianandrelatedmatricesrecentlyplayanimportantroleinthesolu…  相似文献   

16.
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17.
A circular jet has broad and important applications in practical engineering. Most research in this area has focused on a free jet, a wall jet or a vertical jet in a bounded domain. In this study, the mean velocities of circular offset jets were studied for four jet exit Froude numbers (Fr), three offset heights (S) (S/d=1, 2, 3) and three submergence ratios (ht/S) (surface jet, mixed jet, and submerged jet) in a bounded basin. Based on the results, we propose a velocity decay formula for a circular jet. The lateral velocity spread was more consistent with Gaussian and Cauchy–Lorentz distributions than the vertical velocity. Moreover, Fr had little effect on the decay of the mean velocity for a circular jet when Re>1×104. The lateral and vertical spreads showed a quadratic relationship with the streamwise distance for different values of Fr at X/d<10. The positions of maximum mean velocity decay were independent of Fr and S/d when X/d<10. The spread rate was more uniform in the lateral direction than that in the vertical direction in a certain region for different S/d and ht/S. Therefore, the decay, spread, and maximum velocity position of the mean velocity for a circular offset jet can remain stable under different values of Fr, offset height, and submergence ratio.  相似文献   

18.
Chlamydia psittaci is an important zoonotic pathogen in birds and may be transmitted to humans and result in severe respiratory disease. To assess the prevalence and genotype of C. psittaci in birds in Kunming, Yunnan, China, a total of 136 specimens of psittacine birds involving 8 species were collected from the city’s zoos (n=60) and pet markets (n=76). The frequency of C. psittaci infection was 19.9% (27/136) in the psittacine birds. The prevalence of C. psittaci was higher in pet birds (26.3%; 20/76) than in zoo birds (11.7%; 7/60) (P=0.034). In particular, among Agapornis fischeri, the C. psittaci infection (50%; 10/20) was significantly more frequent in the pet markets than in the zoos (P=0.006). In addition, the highest prevalence of 41.2% (7/17) was found in Ara ararauna. To determine the genotype of C. psittaci, 23 OmpA gene fragments (about 1.4 kb) in 27 positive samples were successfully amplified and sequenced. Phylogenetic analysis showed that all the 23 strains belonged to genotype A. Our results demonstrate the high prevalence of C. psittaci genotype A infection in psittacine birds in Yunnan Province, suggesting a potential threat to human health in this area. Therefore, it is necessary to take effective measures to prevent the spread of C. psittaci among psittacine birds, as well as among employees and customers.  相似文献   

19.
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20.

Objective

Salmonella enterica remains a major cause of food-borne disease in humans, and Salmonella Typhimurium (ST) contamination of poultry products is a worldwide problem. Since macrophages play an essential role in controlling Salmonella infection, the aim of this study was to evaluate the effect of glycyrrhizic acid (GA) on immune function of chicken HD11 macrophages.

Methods

Chicken HD11 macrophages were treated with GA (0, 12.5, 25, 50, 100, 200, 400, or 800 μg/ml) and lipopolysaccharide (LPS, 500 ng/ml) for 3, 6, 12, 24, or 48 h. Evaluated responses included phagocytosis, bacteria-killing, gene expression of cell surface molecules (cluster of differentiation 40 (CD40), CD80, CD83, and CD197) and antimicrobial effectors (inducible nitric oxide synthase (iNOS), NADPH oxidase-1 (NOX-1), interferon-γ (IFN-γ), LPS-induced tumor necrosis factor (TNF)-α factor (LITAF), interleukin-6 (IL-6), and IL-10), and production of nitric oxide (NO) and hydrogen peroxide (H2O2).

Results

GA increased the internalization of both fluorescein isothiocyanate (FITC)-dextran and ST by HD11 cells and markedly decreased the intracellular survival of ST. We found that the messenger RNA (mRNA) expression of cell surface molecules (CD40, CD80, CD83, and CD197) and cytokines (IFN-γ, IL-6, and IL-10) of HD11 cells was up-regulated following GA exposure. The expression of iNOS and NOX-1 was induced by GA and thereby the productions of NO and H2O2 in HD11 cells were enhanced. Notably, it was verified that nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) pathways were responsible for GA-induced synthesis of NO and IFN-γ gene expression.

Conclusions

Taken together, these results suggested that GA exhibits a potent immune regulatory effect to activate chicken macrophages and enhances Salmonella-killing capacity.
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