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11.

Background

Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.

Aim

We aimed to determine the association between increased body fat and the immunoglobulin G glycosylation features, comparing body mass index to other measures of body fat distribution.

Methods

We investigated a sample of 637 community-based 45–69?year olds, with mixed phenotypes, residing in Busselton, Western Australia. Body mass index and the waist-to-hip and waist-to-height ratios were calculated using anthropometry, while dual-energy x-ray absorptiometry was performed to gain an accurate measure of total and area specific body fat. Serum immunoglobulin GN-glycans were analysed by ultra-performance liquid chromatography.

Results

Twenty-two N-glycan peaks were found to be associated with at least one of the fat measures. While the previous association of body mass index to agalactosylated immunoglobulin G was replicated, measures of central adiposity explained the most variation in the immunoglobulin G glycome.

Conclusion

Central adiposity is associated with an increased pro-inflammatory fraction of immunoglobulin G, suggesting that the android/gynoid ratio or waist-to-height ratio instead be considered when controlling for adiposity in immunoglobulin G glycome biomarker studies.  相似文献   
12.
A number of molecular genetic studies have investigated if serotonin (5-HT) receptor subtypes are involved in the pathogenesis of depression, suicidal behavior, aggression, and impulsive behavior. Existence of many receptor subtypes for a single transmitter permits a great diversity of signaling raising the possibility that they may serve as genetic markers for suicidal behavior. Most previous studies of suicide have analyzed polymorphisms of the receptors 5-HT1A, 5-HT1B, 5-HT2A, fewer have examined 5-HT1F. We report a study of possible association between the polymorphisms in the 5-HT receptor genes (1A, 1B, 1F, and 2A) and suicidal behavior on a sample of 226 suicide victims and 225 healthy control subjects. No significant differences in genotype frequency distributions between the suicide victims and healthy control subjects were observed for four polymorphisms; three were not polymorphic. A single polymorphism, C-1420T in gene 5-HT2A, showed a slight association with suicide (chi2= 4.94, df = 2, P = 0.067), but the correlation was not statistically significant. None of the tested genetic variants of serotonin receptors appears to be associated with suicidal behavior in the Slovenian population which has a relatively high suicide rate.  相似文献   
13.
Although Smith-Lemli-Opitz Syndrome (SLOS), a genetic condition of impaired cholesterol biosynthesis, is associated with autism [Tierney et al., 2001; Am J Med Genet 98:191-200.], the incidence of SLOS and other sterol disorders among individuals with autism spectrum disorders (ASD) is unknown. This study investigated (1) the incidence of biochemically diagnosed SLOS in blood samples from a cohort of subjects with ASD from families in which more than one individual had ASD and (2) the type and incidence of other sterol disorders in the same group. Using gas chromatography/mass spectrometry, cholesterol, and its precursor sterols were quantified in 100 samples from subjects with ASD obtained from the Autism Genetic Resource Exchange (AGRE) specimen repository. Although no sample had sterol levels consistent with SLOS, 19 samples had total cholesterol levels lower than 100 mg/dl, which is below the 5th centile for children over age 2 years. These findings suggest that, in addition to SLOS, there may be other disorders of sterol metabolism or homeostasis associated with ASD.  相似文献   
14.
The development of the Monte Carlo code SHIELD-HIT (heavy ion transport) for the simulation of the transport of protons and heavier ions in tissue-like media is described. The code SHIELD-HIT, a spin-off of SHIELD (available as RSICC CCC-667), extends the transport of hadron cascades from standard targets to that of ions in arbitrary tissue-like materials, taking into account ionization energy-loss straggling and multiple Coulomb scattering effects. The consistency of the results obtained with SHIELD-HIT has been verified against experimental data and other existing Monte Carlo codes (PTRAN, PETRA), as well as with deterministic models for ion transport, comparing depth distributions of energy deposition by protons, 12C and 20Ne ions impinging on water. The SHIELD-HIT code yields distributions consistent with a proper treatment of nuclear inelastic collisions. Energy depositions up to and well beyond the Bragg peak due to nuclear fragmentations are well predicted. Satisfactory agreement is also found with experimental determinations of the number of fragments of a given type, as a function of depth in water, produced by 12C and 14N ions of 670 MeV u(-1), although less favourable agreement is observed for heavier projectiles such as 16O ions of the same energy. The calculated neutron spectra differential in energy and angle produced in a mimic of a Martian rock by irradiation with 12C ions of 290 MeV u(-1) also shows good agreement with experimental data. It is concluded that a careful analysis of stopping power data for different tissues is necessary for radiation therapy applications, since an incorrect estimation of the position of the Bragg peak might lead to a significant deviation from the prescribed dose in small target volumes. The results presented in this study indicate the usefulness of the SHIELD-HIT code for Monte Carlo simulations in the field of light ion radiation therapy.  相似文献   
15.
The high temperature (up to 220°C.) polymerization of 3,3-bis(chloromethyl)oxetane catalyzed by i-Bu3Al was investigated. The conversion-time curves are of the autocatalytic type and the molecular weight increases lineary with conversion up to the point at which for lower temperatures, e.g. 60–80°C., the whole polymer becomes insoluble. An alternative explanation of this phenomenon is proposed; the formation of insoluble product is related to the entanglement of macromolecules of very high molecular weight and or macrocycle formation in the degradative chain transfer to polymer. The phenomenon of insoluble products formation was never observed at higher temperatures (> 150°C.). The dependence of molecular weight on catalyst and impurity concentrations as well as on the polymerization temperature was investigated. It was shown that the high molecular weight product (\documentclass{article}\pagestyle{empty}\begin{document}$\overline {DP}$\end{document} = 1000–1500) can be produced at 180–220°C. even at rather high impurity level.  相似文献   
16.
The standardization procedures for polymerized ragweed (PRW) must evaluate activity of PRW with assessments that differ from those used for standard unmodified extracts. This is because PRW allergens are different from conventional ragweed extracts in that they are much greater in average molecular weight and much lower in allergenicity for equivalent immunogenicity. We have evaluated seven samples of PRW for three parameters: allergenicity as determined by cutaneous end point titration, molecular weight distribution as determined by Sephadex G-200 chromatography, and availability of antigen E (AgE) determinants as measured by the ability of an extract to inhibit AgE binding to antibody by using a modification of the Farr technique. The skin test titers and molecular weight profiles provide information as to the safety of a PRW preparation and antigen-binding inhibitory activity gives information about allergenicity and immunogenicity. Appropriate limits may be set for each of these parameters to standardize PRW for clinical use.  相似文献   
17.
In the polymerization of 3,3-bis(chloromethyl)oxetane catalyzed by Aliso-C4H9/water catalyst, according to the previously reported data (FURUKAWA, SAEGUSA et al.) insoluble polymers are formed. Although neither the exact mechanism of oxetanes polymerization in the presence of AIR3/H2O catalysts nor the nature of the insoluble polymers are known it is possible to use chain transfer agents to obtain perfectly soluble polymers. The addition of low molecular weight ethers (C2H5)2O, (n-C4H9)2O, (Allyl)2O, 1,4-dioxane, (β-ClC2H4)2O, CH3OPh, and (C6H5)2O in low concentrations leads to the formation of soluble polymers with a very large range of mol. wts. (up to 106). The chain transferabilities of ethers increase with their proton-attracting powers (basicity). In the presence of a chain transfer agent the kinetics of polymerization virtually changes. On the basis of the discussion of the general kinetic behaviors of the system and the dependence of D?P? on conversion it was deduced that in this type of polymerization long living species are formed.  相似文献   
18.
The mechanism of marginal band (MB) formation in differentiating erythroid cells is not fully understood, and the proteins involved in nucleation of MB microtubules are largely unknown. To gain insights into the function of gamma-tubulin in MB formation, we have followed its distribution in developing chicken erythrocytes and characterized soluble forms of the protein. In early stages of erythroid cells differentiation, gamma-tubulin was present in microtubule-organizing centers, mitotic spindles, as well as on MB. Its subcellular localization changed in the course of differentiation, and in postnatal peripheral erythrocytes gamma-tubulin was found only in soluble forms. After cold-induced depolymerization gamma-tubulin in erythroid cells formed large clusters that were not observed in matured cells, and re-growth experiments demonstrated that gamma-tubulin was not present in distinct nucleation structures at the cell periphery. Soluble gamma-tubulin formed complexes of various size and large complexes were prone to dissociation in the presence of high salt concentration. Interaction of gamma-tubulin with tubulin dimers was revealed by precipitation experiments. gamma-Tubulin occurred in multiple charge variants whose number increased in the course of erythrocyte differentiation and corresponded with decreased binding to MB. The presented data demonstrate for the first time that gamma-tubulin is a substrate for developmentally regulated posttranslational modifications and that the binding properties of gamma-tubulin or its complexes change during differentiation events.  相似文献   
19.
Hepatic stellate cells (HSC) and liver myofibroblasts (MFB) are two cell populations most likely responsible for the synthesis of most connective tissue components in fibrotic liver. They differ in their origin and location, and possibly in patterns of gene expression. Normal and carbon tetrachloride-cirrhotic livers from rats were used to isolate HSC. Liver was perfused with pronase and collagenase solutions, followed by centrifugation of the cell suspension on a density gradient. HSC were quiescent 2 days after plating on plastic but they became activated after another 5 days in culture. When the culture was passaged 5 times, its character changed profoundly as HSC were replaced by MFB. Microarray analysis was used to determine gene expression in quiescent HSC, activated HSC and MFB. The expression of 49 genes coding for connective tissue proteins, proteoglycans, metalloproteinases and their inhibitors, growth factors and cellular markers was determined. The pattern of gene expression changed during HSC activation and there were distinct differences between HSC and MFB. Little difference between normal cells and cells isolated from cirrhotic liver was found.  相似文献   
20.
A 51-year-old man, heavy cigarette smoker, a homeless alcoholic, with disseminated lesions in lungs and with ulceration and infiltration of the tongue is presented. Treatment with antibiotics was ineffective. He was admitted to the otolaryngological department because of suspicion of the tongue cancer. The histological examination of the tongue biopsy revealed tuberculous granuloma. In the pulmonological department, on admission the patient was cachectic, with massive oedema and ulceration of the tongue, and enlargement of the cervical lymph nodes. He was fed through the gastric tube. He had severe pain of the tongue demanding treatment with opiates analgesics. Chest x-ray revealed disseminated lesions in lungs. Antituberculous therapy was administered because of suspicion of tuberculosis of the tongue and lungs. During the treatment clinical improvement was observed. Tubercule bacilli were grown in the sputum culture after 6 weeks of observation. After 8 weeks of antituberculous therapy regression of lung lesions and healing of the tongue were observed. The patient continued treatment for 6 months in the Lung Disease Outpatient Clinic.  相似文献   
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