Identification of the conjugated linoleic acid isomer that inhibits milk fat synthesis

Conjugated linoleic acids (CLA) are octadecadienoic fatty acids that have profound effects on lipid metabolism. Our previous work showed that CLA (mixture of isomers) markedly reduced milk fat synthesis. In this study, our objective was to evaluate the effects of specific CLA isomers. Multiparous Holstein cows were used in a 3x3 Latin square design, and treatments were 4-day abomasal infusions of 1) skim milk (control), 2) 9,11 CLA supplement, and 3) 10,12 CLA supplement. CLA supplements provided 10 g/day of the specific CLA isomer (cis-9,trans-11 or trans-10,cis-12). Treatments had no effect on intake, milk yield, or milk protein yield. Only the 10,12 CLA supplement affected milk fat, causing a 42 and 44% reduction in milk fat percentage and yield, respectively. Milk fat composition revealed that de novo synthesized fatty acids were extensively reduced. Increases in ratios of C(14:0) to C(14:1) and C(18:0) to C(18:1) indicated the 10,12 CLA supplement also altered Delta(9)-desaturase. Treatments had minimal effects on plasma concentrations of glucose, nonesterified fatty acids, insulin, or insulin-like growth factor-I. Overall, results demonstrate that trans-10,cis-12 CLA is the isomer responsible for inhibition of milk fat synthesis.     

Dietary galacto-oligosaccharides prevent airway eosinophilia and hyperresponsiveness in a murine house dust mite-induced asthma model

Background

Allergic asthma is strongly associated with the exposure to house dust mite (HDM) and is characterized by eosinophilic pulmonary inflammation and airway hyperresponsiveness (AHR). Recently, there is an increased interest in using dietary oligosaccharides, also known as prebiotics, as a novel strategy to prevent the development of, or reduce, symptoms of allergy.

Aim

We investigated the preventive capacity of dietary galacto-oligosaccharides (GOS) compared to an intra-airway therapeutic treatment with budesonide on the development of HDM-induced allergic asthma in mice.

Methods

BALB/c mice were intranasally sensitized with 1 μg HDM on day 0 followed by daily intranasal challenge with PBS or 10 μg HDM on days 7 to 11. Two weeks prior to the first sensitization and throughout the experiment mice were fed a control diet or a diet containing 1% GOS. Reference mice were oropharyngeally instilled with budesonide (500 μg/kg) on days 7, 9, 11, and 13, while being fed the control diet. On day 14, AHR was measured by nebulizing increasing doses of methacholine into the airways. At the end of the experiment, bronchoalveolar lavage fluid (BALF) and lungs were collected.

Results

Sensitization and challenge with HDM resulted in AHR. In contrast to budesonide, dietary intervention with 1% GOS prevented the development of AHR. HDM sensitization and challenge resulted in a significant increase in BALF leukocytes numbers, which was suppressed by budesonide treatment and dietary intervention with 1% GOS. Moreover, HDM sensitization and challenge resulted in significantly enhanced concentrations of IL-6, CCL17, IL-33, CCL5 and IL-13 in lung tissue. Both dietary intervention with 1% GOS or budesonide treatment significantly decreased the HDM-induced increased concentrations of CCL5 and IL-13 in lung tissue, while budesonide also reduced the HDM-enhanced concentrations of IL-6 and CCL17 in lung tissue.

Conclusion

Not only did dietary intervention with 1% GOS during sensitization and challenge prevent the induction of airway eosinophilia and Th2-related cytokine and chemokine concentrations in the lung equally effective as budesonide treatment, it also prevented AHR development in HDM-allergic mice. GOS might be useful for the prevention and/or treatment of symptoms in asthmatic disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0171-0) contains supplementary material, which is available to authorized users.     

Generation of potent mouse monoclonal antibodies to self-proteins using T-cell epitope “tags”

Immunization of mice or rats with a "non-self" protein is a commonly used method to obtain monoclonal antibodies, and relies on the immune system''s ability to recognize the immunogen as foreign. Immunization of an antigen with 100% identity to the endogenous protein, however, will not elicit a robust immune response. To develop antibodies to mouse proteins, we focused on the potential for breaking such immune tolerance by genetically fusing two independent T-cell epitope-containing sequences (from tetanus toxin (TT) and diphtheria toxin fragment A (DTA)) to a mouse protein, mouse ST2 (mST2). Wild-type CD1 mice were immunized with three mST2 tagged proteins (Fc, TT and DTA) and the specific serum response was determined. Only in mice immunized with the T-cell epitope-containing antigens were specific mST2 serum responses detected; hybridomas generated from these mice secreted highly sequence-diverse IgGs that were capable of binding mST2 and inhibiting the interaction of mST2 with its ligand, mouse interleukin (IL)-33 (mIL-33). Of the hundreds of antibodies profiled, we identified five potent antibodies that were able to inhibit IL-33 induced IL-6 release in a mast cell assay; notably one such antibody was sufficiently potent to suppress IL-5 release and eosinophilia infiltration in an Alternaria alternata challenge mouse model of asthma. This study demonstrated, for the first time, that T-cell epitope-containing tags have the ability to break tolerance in wild-type mice to 100% conserved proteins, and it provides a compelling argument for the broader use of this approach to generate antibodies against any mouse protein or conserved ortholog.     

Are patients with non-ST elevation myocardial infarction undertreated?

Background

We have previously documented significant differences in orthogonal P wave morphology between patients with and without paroxysmal atrial fibrillation (PAF). However, there exists little data concerning normal P wave morphology. This study was aimed at exploring orthogonal P wave morphology and its variations in healthy subjects.

Methods

120 healthy volunteers were included, evenly distributed in decades from 20–80 years of age; 60 men (age 50+/-17) and 60 women (50+/-16). Six-minute long 12-lead ECG registrations were acquired and transformed into orthogonal leads. Using a previously described P wave triggered P wave signal averaging method we were able to compare similarities and differences in P wave morphologies.

Results

Orthogonal P wave morphology in healthy individuals was predominately positive in Leads X and Y. In Lead Z, one third had negative morphology and two-thirds a biphasic one with a transition from negative to positive. The latter P wave morphology type was significantly more common after the age of 50 (P < 0.01). P wave duration (PWD) increased with age being slightly longer in subjects older than 50 (121+/-13 ms vs. 128+/-12 ms, P < 0.005). Minimal intraindividual variation of P wave morphology was observed.

Conclusion

Changes of signal averaged orthogonal P wave morphology (biphasic signal in Lead Z), earlier reported in PAF patients, are common in healthy subjects and appear predominantly after the age of 50. Subtle age-related prolongation of PWD is unlikely to be sufficient as a sole explanation of this finding that is thought to represent interatrial conduction disturbances. To serve as future reference, P wave morphology parameters of the healthy subjects are provided.     

Skewed distribution of proinflammatory CD4+CD28null T cells in rheumatoid arthritis

Expanded populations of CD4+ T cells lacking the co-stimulatory molecule CD28 (CD4+CD28null T cells) have been reported in several inflammatory disorders. In rheumatoid arthritis, increased frequencies of CD4+CD28null T cells in peripheral blood have previously been associated with extra-articular manifestations and human cytomegalovirus (HCMV) infection, but their presence in and contribution to joint manifestations is not clear. In the present article we investigated the distribution of CD4+CD28null T cells in the synovial membrane, synovial fluid and peripheral blood of RA patients, and analysed the association with erosive disease and anti-citrullinated protein antibodies. CD4+CD28null T cells were infrequent in the synovial membrane and synovial fluid, despite significant frequencies in the circulation. Strikingly, the dominant TCR-Vbeta subsets of CD4+CD28null T cells in peripheral blood were often absent in synovial fluid. CD4+CD28null T cells in blood and synovial fluid showed specificity for HCMV antigens, and their presence was clearly associated with HCMV seropositivity but not with anti-citrullinated protein antibodies in the serum or synovial fluid, nor with erosive disease. Together these data imply a primary role for CD4+CD28null T cells in manifestations elsewhere than in the joints of patients with HCMV-seropositive rheumatoid arthritis.     

Sequestration of adenosine in crude extract from mouse liver and other tissues.

Adenosine (1 microM) was incubated in the presence of dialyzed crude tissue extract from mouse liver and its degradation determined. At high concentration of tissue extract, a fraction of adenosine was not metabolized. This phenomenon, termed sequestration of adenosine, was shown to be affected in the same way by the same factors (pH, salt, reducing agent and adenine) as those affecting the protection of adenosine against deamination in the presence of the purified cyclic AMP-adenosine binding protein/S-adenosylhomocysteinase from mouse liver (Saeb?, J. and Ueland, P.M. (1979) Biochim. Biophys. Acta 587, 333--340). These data point to a role of this protein in the sequestration of adenosine in crude extract. The sequestration potency in crude extract could be determined by diluting the extract in the presence of a constant amount of adenosine deaminase added to the tissue extract. Under these conditions there was linearity of adenosine not available for degradation versus the concentration of tissue extract, and a total recovery of the sequestration potency of purified binding protein added to the crude extract was observed. The tissue level of the cyclic AMP-adenosine binding protein/S-adenosylhomocysteinase in mouse liver was determined by two independent procedures based on the sequestration of adenosine and the hydrolysis of S-adenosylhomocysteine, respectively. The intracellular concentration was calculated to be 10 microM. The sequestration of adenosine in crude extract from mouse, rat, rabbit and bovine tissues was determined and showed requirements similar to those of the sequestration in mouse liver extract. The ability to sequester adenosine was high in liver and decreased in the following order: liver, kidney, adrenal cortex, brain, uterus, cardiac and skeletal muscle.     

ACE I/D and MTHFR C677T polymorphisms are significantly associated with type 2 diabetes in Arab ethnicity: A meta-analysis

In this meta-analysis study, SNPs were investigated for their association with type 2 diabetes (T2D) in both Arab and Caucasian ethnicities. A total of 55 SNPs were analyzed, of which 11 fulfilled the selection criteria, and were used for analysis. It was found that TCF7L2 rs7903146 was significantly associated with a pooled OR of 1.155 (95%C.I. = 1.059–1.259), p < 0.0001 and I² = 78.30% among the Arab population, whereas among Caucasians, the pooled OR was 1.45 (95%C.I. = 1.386–1.516), p < 0.0001 and I² = 77.20%. KCNJ11 rs5219 was significantly associated in both the populations with a pooled OR of 1.176(1.092–1.268), p < 0.0001 and I² = 32.40% in Caucasians and a pooled OR of 1.28(1.111–1.475), p = 0.001 among Arabs. The ACE I/D polymorphism was found to be significantly associated with a pooled OR of 1.992 (95%C.I. = 1.774–2.236), p < 0.0001 and I² = 83.20% among the Arab population, whereas among Caucasians, the pooled OR was 1.078 (95%C.I. = 0.993–1.17), p = 0.073 and I² = 0%. Similarly, MTHFR C677T polymorphism was also found to be significantly associated among Arabs with a pooled OR of 1.924 (95%C.I. = 1.606–2.304), p < 0.0001 and I² = 27.20%, whereas among Caucasians, the pooled OR was 0.986 (95%C.I. = 0.868–1.122), p = 0.835 and I² = 0%. Meanwhile PPARG-2 Pro12Ala, CDKN2A/2B rs10811661, IGF2BP2 rs4402960, HHEX rs7923837, CDKAL1 rs7754840, EXT2 rs1113132 and SLC30A8 rs13266634 were found to have no significant association with T2D among Arabs. In conclusion, it seems from this study that both Arabs and Caucasians have different SNPs associated with T2D. Moreover, this study sheds light on the profound necessity for further investigations addressing the question of the genetic components of T2D in Arabs.     

Impact of 900 MHz electromagnetic field exposure on main male reproductive hormone levels: a Rattus norvegicus model

This work analyzes the effects of radiofrequency-electromagnetic field (RF-EMF) exposure on the reproductive system of male rats, assessed by measuring circulating levels of FSH, LH, inhibin B, activin B, prolactin, and testosterone. Twenty adult male Sprague–Dawley rats (180?±?10 g) were exposed to 900 MHz RF-EMF in four equal separated groups. The duration of exposure was 1, 2, and 4 h/day over a period of 30 days and sham-exposed animals were kept under the same environmental conditions as the exposed group except with no RF-EMF exposure. Before the exposure, at 15 and 30 days of exposure, determination of the abovementioned hormone levels was performed using ELISA. At the end of the experiment, FSH and LH values of the long time exposure (LTE) group were significantly higher than the sham-exposed group (p?p?p?相似文献   

Comparative Estimation of Genetic Diversity in Population Studies using Molecular Sampling and Traditional Sampling Methods

Entomopathogenic nematodes (EPN) are efficient biological pest control agents. Population genetics studies on EPN are seldom known. Therefore, it is of interest to evaluate the significance of molecular sampling method (MSM) for accuracy, time needed, and cost effectiveness over traditional sampling method (TSM). The study was conducted at the Mohican Hills golf course at the state of Ohio where the EPN H. bacteriophora has been monitored for 18 years. The nematode population occupies an area of approximately 3700 m² with density range from 0.25-2 per gram soil. Genetic diversity of EPN was studied by molecular sampling method (MSM) and traditional sampling method (TSM) using the mitochondrial gene pcox1. The MSM picked 88% in compared to TSM with only 30% of sequenced cox 1 gene. All studied genetic polymorphism measures (sequence and haplotype) showed high levels of genetic diversity of MSM over TSM. MSM minimizes the chance of mitochondrial genes amplification from non target organisms (insect or other contaminating microorganisms). Moreover, it allows the sampling of more individuals with a reliable and credible representative sample size. Thus, we show that MSM supersedes TSM in labour intensity, time consumption and requirement of no special experience and efficiency.