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Publication
Journal: Acta Neuropathologica
August/11/1985
Abstract
Oligosaccharide residues on the endothelial luminal plasma membrane of rat cerebral cortical vessels were localized using biotinylated lectins. In addition, the effect of pretreatment of brain slices with neuraminidase prior to the binding of cationized ferritin (CF) and certain lectins was studied. Conjugates of biotinylated lectins and avidin-D horseradish peroxidase reaction product were evenly distributed on the endothelium of arterioles, capillaries, and venules. Lectin binding sites were observed on the plasma membrane of pinocytotic vesicles open onto the vascular lumen and at the luminal end of the interendothelial space only. The following sugar residues were localized: alpha-D-mannosyl, alpha-D-glucosyl, beta-N-acetylglucosaminyl, sialyl, D-galactosyl, alpha-L-fucosyl, and alpha-N-acetyl-D-galactosaminyl. Following pretreatment of brain slices with neuraminidase beta-D-gal-(1-3)-D-galN-acetyl groups were demonstrated on endothelium. In this respect, cerebral endothelium differs from noncerebral endothelium which is reported to have peanut agglutinin binding sites without neuraminidase pretreatment. Anionic groups on cerebral endothelium were demonstrated at the same locations as the lectin binding sites. Following neuraminidase pretreatment there was reduction, but not absence, of CF binding supporting the observation that surface charge is not wholly due to sialyl groups. The role of monosaccharide residues in states of altered cerebrovascular permeability remains to be determined.
Authors
Publication
Journal: Experimental Brain Research
November/13/2006
Abstract
In-utero alcohol exposure produces sensorimotor developmental abnormalities that often persist into adulthood. The rodent cortical barrel field associated with the representation of the body surface was used as our model system to examine the effect of prenatal alcohol exposure (PAE) on early somatosensory cortical development. In this study, pregnant female rats were intragastrically gavaged daily with high doses of alcohol (6 gm/kg body weight) throughout the first 20 days of pregnancy. Blood alcohol levels were measured in the pregnant dams on gestational days 13 (G13) and G20. The ethanol treated group (EtOH) was compared to the normal control chowfed (CF) group, nutritionally matched pairfed (PF) group, and cross-foster (XF) group. Cortical barrel development was examined in pups across all treatment groups from G25, corresponding to postnatal day 2 (P2), to G32 corresponding to P9. The EtOH and control group pups were weighed, anesthetized, and perfused. Brains were removed and weighed with, and without cerebellum and olfactory bulbs, and neocortex was removed and weighed. Cortices were then flattened, sectioned tangentially, and stained with a metabolic marker, cytochrome oxidase (CO) to reveal the barrel field. Progression of barrel development was distinguished into three categories: (a) absent, (b) cloudy barrel-like pattern, and (c) well-formed barrels with intervening septae. The major findings are: (1) PAE delayed barrel field development by one or more days, (2) the barrel field first appeared as a cloudy pattern that gave way on subsequent days to an adult-like pattern with clearly demarcated intervening septal regions, (3) the barrel field developed differentially in a lateral-to-medial gradient in both alcohol and control groups, (4) PAE delayed birth by one or more days in 53% of the pups, (5) regardless of whether pups were born on G23 (normal expected birth date for non-alcohol controls) or as in the case for the alcohol-delayed pups born as late as G27, the barrel field was never present at birth suggesting the importance of postnatal experience on barrel field development, and (6) PAE did not disrupt the normal barrel field pattern, although both total body and brain weights were compromised. These findings suggest that PAE delays the development of the somatosensory cortex (SI); such delays may interfere with timing and formation of cortical circuits. It is unknown whether other nuclei along the somatosensory pathway undergo similar delays in development or if PAE selectively disrupts cortical circuitry.
Publication
Journal: Journal of Biological Chemistry
December/26/2011
Abstract
MraY translocase catalyzes the first committed membrane-bound step of bacterial peptidoglycan synthesis leading to the formation of lipid I. The essential membrane protein therefore has a high potential as target for drug screening approaches to develop antibiotics against gram-positive as well as gram-negative bacteria. However, the production of large integral membrane proteins in conventional cellular expression systems is still very challenging. Cell-free expression technologies have been optimized in recent times for the production of membrane proteins in the presence of detergents (D-CF), lipids (L-CF), or as precipitates (P-CF). We report the development of preparative scale production protocols for the MraY homologues of Escherichia coli and Bacillus subtilis in all three cell-free expression modes followed by their subsequent quality evaluation. Although both proteins can be cell-free produced at comparable high levels, their requirements for optimal expression conditions differ markedly. B. subtilus MraY was stably folded in all three expression modes and showed highest translocase activities after P-CF production followed by defined treatment with detergents. In contrast, the E. coli MraY appears to be unstable after post- or cotranslational solubilization in detergent micelles. Expression kinetics and reducing conditions were identified as optimization parameters for the quality improvement of E. coli MraY. Most remarkably, in contrast to B. subtilis MraY the E. coli MraY has to be stabilized by lipids and only the production in the L-CF mode in the presence of preformed liposomes resulted in stable and translocase active protein samples.
Publication
Journal: Inorganic Chemistry
July/16/2003
Abstract
We have synthesized a triamidoamine ligand ([(RNCH(2)CH(2))(3)N](3)(-)) in which R is 3,5-(2,4,6-i-Pr(3)C(6)H(2))(2)C(6)H(3) (hexaisopropylterphenyl or HIPT). The reaction between MoCl(4)(THF)(2) and H(3)[HIPTN(3)N] in THF followed by 3.1 equiv of LiN(SiMe(3))(2) led to formation of orange [HIPTN(3)N]MoCl. Reduction of MoCl (Mo = [HIPTN(3)N]Mo) with magnesium in THF under dinitrogen led to formation of salts that contain the ((Mo(N(2)))(-) ion. The (Mo(N(2)))(-) ion can be oxidized by zinc chloride to give Mo(N(2)) or protonated to give MoN=NH. The latter was found to decompose to yield MoH. Other relevant compounds that have been prepared include (Mo=N-NH(2))(+) (by protonation of MoN=NH), M=1;N, (Mo=NH)(+) (by protonation of M=N), and (Mo(NH(3)))(+) (by treating MoCl with ammonia). (The anion is usually (B(3,5-(CF(3))(2)C(6)H(3))(4))(-) = (BAr'(4))(-).) X-ray studies were carried out on (Mg(DME)(3))(0.5)[Mo(N(2))], MoN=NMgBr(THF)(3), Mo(N(2)), M=N, and (Mo(NH(3)))(BAr'(4)). These studies suggest that the HIPT substituent on the triamidoamine ligand creates a cavity that stabilizes a variety of complexes that might be encountered in a hypothetical Chatt-like dinitrogen reduction scheme, perhaps largely by protecting against bimolecular decomposition reactions.
Publication
Journal: European Journal of Pediatrics
February/14/2001
Abstract
Continuous infusion (CI) of beta-lactam antibiotics provides a stable concentration which may result in a better activity against gram-negative bacteria if exceeding the minimum inhibitory concentration (MIC). Treatment outcome after 24 h CI of ceftazidime (CAZ) in cystic fibrosis (CF) children was compared with the bolus administration regimen. Fourteen CF children with chronic Pseudomonas aeruginosa pulmonary infection were treated during 14 days with the conventional CAZ thrice-a-day bolus infusion (regimen A), and few months later with 24 h Cl of CAZ (regimen B) using a portable pump. Amikacin was added to both regimens. Clinical efficacy of treatment was assessed using pulmonary, inflammatory and nutritional variables. Bacteriological analyses and CAZ concentrations in serum and sputum were also measured. All patients improved clinically with both regimens. Among the parameters used to compare both regimens, only prealbumin values improved (regimen A: + 0.08 g/l versus regimen B: +0.11 g/l P = 0.015). No clinically significant side-effects were noted. In regimen A, the mean predose (trough level) CAZ concentration in serum was highly variable (range 2.2-45.4 gg/ml) with some values (32% of samples) below the MIC of P. aeruginosa isolates found in the sputum of the patients. In regimen B, the serum CAZ level achieved was 28.5+/-8.4 microg/ml without any value below the MIC. The mean sputum levels were comparable in both regimens. No CAZ resistant strains of P. aerugino.sa appeared between and directly after the treatments.
CONCLUSIONS
The clinical outcome of children with cystic fibrosis treated with 24 h continuous infusion of ceftazidime was no different from that achieved with the conventional bolus infusion regimen. Continuous infusion provided a sustained serum ceftazidime level well above the P. aeruginosa minimum inhibitory concentration. Continuous infusion was well tolerated and appreciated by the children and this may promote home therapy for cystic fibrosis children.
Publication
Journal: Neuroendocrinology Letters
September/7/2008
Abstract
BACKGROUND
It has been shown that chronic fatigue syndrome (CFS) and major depression (MDD) are accompanied by signs of oxidative stress and by a decreased antioxidant status. The aim of the present study was to examine whether CFS and MDD are accompanied by an IgM-mediated immune response directed against nitro-serum bovine albumin (BSA), which is a neoepitope of BSA formed by damage caused by nitrosative stress.
OBJECTIVE
Toward this end, we examined serum IgM antibodies to nitro-BSA in 13 patients with CFS, 14 subjects with partial CFS, 16 patients with MDD and 11 normal controls.
RESULTS
We found that the prevalence and mean values for the serum IgM levels directed against nitro-BSA were significantly greater in patients with partial CFS, CFS and MDD than in normal controls, and significantly greater in CFS than in those with partial CFS and MDD. We found significant and positive correlations between serum IgM levels directed against nitro-BSA and symptoms of the FibroFatigue scale, i.e. aches and pain and muscular tension. There was also a strong positive correlation between serum IgM titers directed against nitro-BSA and an index of increased gut permeability ("leaky gut"), i.e. serum IgM and IgA directed against LPS of different gram-negative enterobacteria.
CONCLUSIONS
The abovementioned results indicate that both CFS and MDD are accompanied by a) an increased gut permeability which has allowed an exaggerated passage of BSA through a compromised epithelial barrier; b) increased nitrosative stress which has induced damage to BSA; and c) an IgM-mediated immune response which is directed against the nitro-BSA neoepitopes. Nitrosative stress is one of the factors underpinning the comorbidity and clinical overlap between CFS and MDD.
Publication
Journal: Journal of General Physiology
April/30/2003
Abstract
1. Lysogenic B. megatherium 899a was adapted to growth in a minimal ammonium sulfate medium (ASCM). 2. Adaptation took place slowly and the following changes in the culture occurred: (a) The growth rate increased from 0.5 to 1.5-2.0/hr. (b) The culture changed from diffuse to mucoid. (c) The total phage titer, and the gelatinase concentration decreased to 1/100 or less. (d) The types of phage produced changed from >99 per cent T (wild type) to 30 to 60 per cent miscellaneous clear types. The original T phage was replaced by a different smaller t, never observed in the original 899a culture. (e) Several new colony types also appeared, but the colony morphology was not correlated with the phage types produced. None of the colony types was stable on repeated transfer either in peptone or ASCM, but continued to disassociate into different colony types (cf. Ivánovics, 1955). 3. Control experiments showed that these changes in phage production and colony types could not be brought about by growing sensitive B. megatherium in the presence of the various new phages, in ASCM. It is therefore unlikely that the changes observed in adapted culture were due to infection of a sensitive cell with phage. 4. Continued growth of the ASCM-adapted strain in peptone resulted in increasing the total phage titer, and also the gelatinase concentration. The growth rate returned to its original value and the ability to grow rapidly in ASCM was soon lost. The phage types, however, remained the same as in the ASCM. 5. An improved cell for steady state growth is described.
Publication
Journal: Journal of Bacteriology
May/9/1967
Abstract
A mixture of beta-glucosidases from Saccharomyces fragilis (Y-18) and S. dobzhanskii (Y-19) eluted from diethylaminoethyl cellulose in two peaks, whereas the enzyme from a hybrid, S. fragilis x S. dobzhanskii (Y-42), eluted in a single broad peak. The highest Y-42 activity fractions eluted at a sodium chloride molarity which was intermediate to the molarities at which most of the Y-18 and Y-19 activity was eluted. In cellulose polyacetate strips, Y-42 enzyme migrated as a diffuse band which spanned the distances migrated by the enzymes from the parent yeast strains. Antisera against either Y-18 or Y-19 enzyme precipitated 80 to 90% of Y-42 enzyme activity. When Y-42 enzyme was dissociated by heat or urea and reacted with parental antiserum, a concomitant increase in the opposite parental activity was demonstrable in both precipitation and complement-fixation (CF) tests. Urea-dissociated beta-glucosidases were resolvable by sucrose-gradient centrifugation into multiple bands displaying specific CF activity. When the enzymes were exposed to 4 m urea for 12 min, particles of approximately 110,000 molecular weight were obtained. By extending the exposure time to 40 min, and incorporating 0.5 m urea in the gradients, smaller particles were detected with molecular weights ranging from 18,000 to 23,000. Attempts to regenerate enzyme activity after dissociation with urea were only moderately successful. Results suggested that a slightly acidic environment favored reassociation, as did the presence of 2-mercaptoethanol. Residual urea also seemed important. It is proposed that the structural genes for both Y-18 and Y-19 enzyme are present in Y-42 cells with either independent or closely interacting regulatory mechanisms. Since synthesis of the two parental-type polypeptides may be unequal, the availability of enzyme subunits for subsequent polymerization in the cell cytoplasm might be equalized at the polysome level. Random association of subunits would produce a binomial distribution of true hybrid enzyme molecules.
Publication
Journal: FEBS Letters
February/2/2000
Abstract
Rotation of the gamma subunit in chloroplast F(1)-ATPase (CF(1)) was investigated by using a single molecule observation technique, which is developed by Noji et al. to observe the rotation of a central gamma subunit portion in the alpha(3)beta(3)gamma sub-complex of F(1)-ATPase from thermophilic Bacillus PS3 (TF(1)) during ATP hydrolysis [Noji, H. et al. (1997) Nature 386, 299-302]. We used two cysteines of the gamma subunit (Cys-199 and Cys-205) of CF(1)-ATPase, which are involved in the regulation of this enzyme, to fix the fluorochrome-labeled actin filament. Then we successfully observed a unidirectional, counter-clockwise rotation of the actin filament with the fluorescent microscope indicating the rotation of the gamma subunit in CF(1)-ATPase. We conclude that the rotation of the gamma subunit in the F(1)-motor is a ubiquitous phenomenon in all F(1)-ATPases in prokaryotes as well as in eukaryotes.
Publication
Journal: Journal of Biological Chemistry
April/15/1986
Abstract
The pathway for synthesis of three glycosphingolipids bearing a common sialyl-Lex determinant (NeuAc alpha 2----3Gal beta 1----4[Fuc alpha 1----3]GlcNac beta 1----R) from their type 2 lactoseries precursors has been studied using the 0.2% Triton X-100-soluble fraction from human lung carcinoma PC9 cells. Two enzymes were found to be required for their synthesis: (i) an alpha 1----3 fucosyltransferase, the properties of which have been characterized as being similar to the enzyme from human small cell lung carcinoma NCI-H69 cells (Holmes, E. H., Ostrander, G. K., and Hakomori, S. (1985) J. Biol. Chem. 260, 7619-7627); and (ii) an alpha 2----3 sialyltransferase that was efficiently solubilized by 0.2% Triton X-100 and required divalent metal ions and 0.3% Triton CF-54 for optimal activity at pH 5.9 in cacodylate buffer. Biosynthesis of the sialyl-Lex determinant was shown to proceed via sialylation of nLc6 and nLc4, followed by alpha 1----3 fucosylation at the penultimate GlcNAc residues, based on the following: (i) transfer of NeuAc by PC9 cell sialyltransferase was found only when the nonfucosylated acceptors nLc4 and nLc6 were added, and none of the glycolipids with Lex structure (III3FucnLc4; V3FucnLc6; III3V3Fuc2nLc6) were sialylated; and (ii) the PC9 cell fucosyltransferase was active with both neutral and ganglioside neolacto (type 2 chain) acceptors. Transfer of fucose to VI3NeuAcnLc6 yielded mono- and difucosyl derivatives, whereas only a monofucosyl derivative was obtained when VI6NeuAcnLc6 was the acceptor. This is most probably due to different conformations at the terminus of the two acceptor gangliosides. The fucosyltransferase was incapable of transferring fucose to sialyl 2----3 lactotetraosylceramide (IV3NeuAcLc4).
Publication
Journal: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
January/20/2010
Abstract
To determine what capabilities wood-eating and detritivorous catfishes have for the digestion of refractory polysaccharides with the aid of an endosymbiotic microbial community, the pH, redox potentials, concentrations of short-chain fatty acids (SCFAs), and the activity levels of 14 digestive enzymes were measured along the gastrointestinal (GI) tracts of three wood-eating taxa (Panaque cf. nigrolineatus "Marañon", Panaque nocturnus, and Hypostomus pyrineusi) and one detritivorous species (Pterygoplichthys disjunctivus) from the family Loricariidae. Negative redox potentials (-600 mV) were observed in the intestinal fluids of the fish, suggesting that fermentative digestion was possible. However, SCFA concentrations were low (<3 mM in any intestinal region), indicating that little GI fermentation occurs in the fishes' GI tracts. Cellulase and xylanase activities were low (<0.03 U g(-1)), and generally decreased distally in the intestine, whereas amylolytic and laminarinase activities were five and two orders of magnitude greater, respectively, than cellulase and xylanase activities, suggesting that the fish more readily digest soluble polysaccharides. Furthermore, the Michaelis-Menten constants (K(m)) of the fishes' beta-glucosidase and N-acetyl-beta-D-glucosaminidase enzymes were significantly lower than the K(m) values of microbial enzymes ingested with their food, further suggesting that the fish efficiently digest soluble components of their detrital diet rather than refractory polysaccharides. Coupled with rapid gut transit and poor cellulose digestibility, the wood-eating catfishes appear to be detritivores reliant on endogenous digestive mechanisms, as are other loricariid catfishes. This stands in contrast to truly "xylivorous" taxa (e.g., beavers, termites), which are reliant on an endosymbiotic community of microorganisms to digest refractory polysaccharides.
Publication
Journal: Journal of Clinical Microbiology
March/28/2010
Abstract
With the recent insights into the Streptococcus milleri group (SMG) as pulmonary pathogens in patients with cystic fibrosis (CF), we sought to characterize 128 isolates from the sputum of adults with CF, along with 45 isolates from patients with invasive diseases for comparison. The tests performed included Lancefield grouping; tests for hemolysis; tests for the production of hyaluronidase, chondroitin sulfatase, DNase, proteases, and hydrogen peroxide; and PCR for the detection of the intermedilysin gene (ily). We also generated biochemical profiles with the Rapid ID Strep 32 API system and tested cell-free supernatants for the presence of the signal molecule autoinducer-2 (AI-2) using a Vibrio harveyi bioassay with a subset of CF strains. The S. intermedius isolates from both strain collections were similar, while the S. constellatus and S. anginosus isolates yielded several biotypes that differed in prevalence between the two strain collections. Beta-hemolytic, Lancefield group C S. constellatus comprised 74.4% of the S. constellatus isolates from patients with CF but only 13.3% of the corresponding isolates from patients with invasive infections. This was the only S. constellatus biotype associated with pulmonary exacerbations. Hyaluronidase-positive S. anginosus was detected only among the isolates from patients with CF. Strain-to-strain variability in AI-2 expression was evident, with the mean values being the highest for S. anginosus, followed by S. constellatus and then S. intermedius. Cluster analysis and 16S rRNA sequencing revealed that the species of SMG could be accurately determined with a minimum of three phenotypic tests: tests for the Lancefield group, hyaluronidase production, and chondroitin sulfatase production. Furthermore, isolates from patients with invasive infections clustered with isolates from the sputum of patients with CF, suggesting that the respiratory tract isolates were equally pathogenic.
Publication
Journal: Journal of the American Chemical Society
July/8/2012
Abstract
Readily prepared and bench-stable rhodium complexes containing methylene bridged diphosphine ligands, viz. [Rh(C(6)H(5)F)(R(2)PCH(2)PR'(2))][BAr(F)(4)] (R, R' = (t)Bu or Cy; Ar(F) = C(6)H(3)-3,5-(CF(3))(2)), are shown to be practical and very efficient precatalysts for the intermolecular hydroacylation of a wide variety of unactivated alkenes and alkynes with β-S-substituted aldehydes. Intermediate acyl hydride complexes [Rh((t)Bu(2)PCH(2)P(t)Bu(2))H{κ(2)(S,C)-SMe(C(6)H(4)CO)}(L)](+) (L = acetone, MeCN, [NCCH(2)BF(3)](-)) and the decarbonylation product [Rh((t)Bu(2)PCH(2)P(t)Bu(2))(CO)(SMePh)](+) have been characterized in solution and by X-ray crystallography from stoichiometric reactions employing 2-(methylthio)benzaldehdye. Analogous complexes with the phosphine 2-(diphenylphosphino)benzaldehyde are also reported. Studies indicate that through judicious choice of solvent and catalyst/substrate concentration, both decarbonylation and productive hydroacylation can be tuned to such an extent that very low catalyst loadings (0.1 mol %) and turnover frequencies of greater than 300 h(-1) can be achieved. The mechanism of catalysis has been further probed by KIE and deuterium labeling experiments. Combined with the stoichiometric studies, a mechanism is proposed in which both oxidative addition of the aldehyde to give an acyl hydride and insertion of the hydride into the alkene are reversible, with the latter occurring to give both linear and branched alkyl intermediates, although reductive elimination for the linear isomer is suggested to have a considerably lower barrier.
Publication
Journal: BMC Cancer
February/24/2009
Abstract
BACKGROUND
Epidemiological studies suggest that physical activity reduces the risk of colon cancer in humans. Results from animal studies, however, are inconclusive. The present study investigated the effects of voluntary exercise on intestinal tumor formation in two different animal models, Apc(Min/+) mice and azoxymethane (AOM)/dextran sulfate sodium (DSS)-treated mice.
METHODS
In Experiments 1 and 2, five-week old female Apc(Min/+) mice were either housed in regular cages or cages equipped with a running wheel for 6 weeks (for mice maintained on the AIN93G diet; Experiment 1) or 9 weeks (for mice on a high-fat diet; Experiment 2). In Experiment 3, male CF-1 mice at 6 weeks of age were given a dose of AOM (10 mg/kg body weight, i.p.) and, 12 days later, 1.5% DSS in drinking fluid for 1 week. The mice were then maintained on a high-fat diet and housed in regular cages or cages equipped with a running wheel for 16 weeks.
RESULTS
In the Apc(Min/+) mice maintained on either the AIN93G or the high-fat diet, voluntary exercise decreased the number of small intestinal tumors. In the AOM/DSS-treated mice maintained on a high-fat diet, voluntary exercise also decreased the number of colon tumors. In Apc(Min/+) mice, voluntary exercise decreased the ratio of serum insulin like growth factor (IGF)-1 to IGF binding protein (BP)-3 levels. It also decreased prostaglandin E2 and nuclear beta-catenin levels, but increased E-cadherin levels in the tumors.
CONCLUSIONS
These results indicate hat voluntary exercise inhibited intestinal tumorigenesis in Apc(Min/+) mice and AOM/DSS-treated mice, and the inhibitory effect is associated with decreased IGF-1/IGFBP-3 ratio, aberrant beta-catenin signaling, and arachidonic acid metabolism.
Publication
Journal: Analytical and Bioanalytical Chemistry
July/9/2009
Abstract
Presented here is the optimization and development of a desorption electrospray ionization mass spectrometry (DESI-MS) method for detecting natural products on tissue surfaces. Bromophycolides are algal diterpene-benzoate macrolide natural products that have been shown to inhibit growth of the marine fungal pathogen Lindra thalassiae. As such, they have been implicated in antimicrobial chemical defense. However, the defense mechanisms are not yet completely understood. Precise detection of these compounds on algal tissue surfaces under ambient conditions without any disruptive sample processing could shed more light onto the processes involved in chemical defense of marine organisms. Conventional DESI-MS directly on algal tissue showed relatively low sensitivity for bromophycolide detection. Sensitivity was greatly improved by the addition of various anions including Cl(-), Br(-), and CF(3)COO(-) into the DESI spray solvent. Chloride adduction gave the highest sensitivity for all assayed anions. Density functional optimization of the bromophycolide anionic complexes produced during DESI supported this observation by showing that the chloride complex has the most favorable binding energy. Optimized DESI protocols allowed the direct and unambiguous detection of bromophycolides, including A, B, and E, from the surface of untreated algal tissue.
Publication
Journal: Cardiovascular Diabetology
January/14/2016
Abstract
BACKGROUND
The cardio ankle vascular index (CAVI) is a new index of the overall stiffness of the artery from the origin of the aorta to the ankle. This index can estimate the risk of atherosclerosis. We aimed to find the relationship between CAVI and target organ damage (TOD), vascular structure and function, and cardiovascular risk factors in Caucasian patients with type 2 diabetes mellitus or metabolic syndrome.
METHODS
We included 110 subjects from the LOD-Diabetes study, whose mean age was 61 ± 11 years, and 37.3% were women. Measurements of CAVI, brachial ankle pulse wave velocity (ba-PWV), and ankle brachial index (ABI) were taken using the VaSera device. Cardiovascular risk factors, renal function by creatinine, glomerular filtration rate, and albumin creatinine index were also obtained, as well as cardiac TOD with ECG and vascular TOD and carotid intima media thickness (IMT), carotid femoral PWV (cf-PWV), and the central and peripheral augmentation index (CAIx and PAIx). The Framingham-D'Agostino scale was used to measure cardiovascular risk.
RESULTS
Mean CAVI was 8.7 ± 1.3. More than half (54%) of the participants showed one or more TOD (10% cardiac, 13% renal; 48% vascular), and 13% had ba-PWV ≥ 17.5 m/s. Patients with any TOD had the highest CAVI values: 1.15 (CI 95% 0.70 to 1.61, p < 0.001) and 1.14 (CI 95% 0.68 to 1.60, p < 0.001) when vascular TOD was presented, and 1.30 (CI 95% 0.51 to 2.10, p = 0.002) for the cardiac TOD. The CAVI values had a positive correlation with HbA1c and systolic and diastolic blood pressure, and a negative correlation with waist circumference and body mass index. The positive correlations of CAVI with IMT (β = 0.29; p < 0.01), cf-PWV (β = 0.83; p < 0.01), ba-PWV (β = 2.12; p < 0.01), CAIx (β = 3.42; p < 0.01), and PAIx (β = 5.05; p = 0.04) remained after adjustment for cardiovascular risk, body mass index, and antihypertensive, lipid-lowering, and antidiabetic drugs.
CONCLUSIONS
The results of this study suggest that the CAVI is positively associated with IMT, cf-PWV, ba-PWV, CAIx, and PAIx, regardless of cardiovascular risk and the drug treatment used. Patients with cardiovascular TOD have higher values of CAVI.
BACKGROUND
Clinical Trials.gov Identifier: NCT01065155.
Publication
Journal: Diabetic Medicine
February/21/2010
Abstract
OBJECTIVE
Although cystic fibrosis-related diabetes (CFRD), a poor prognostic factor in cystic fibrosis (CF), is characterized by insulinopenia, the role of insulin resistance is unclear. Using a prospective study design, we measured insulin resistance, pancreatic beta-cell function and correlated glycaemic status with clinical parameters.
METHODS
Oral glucose tolerance test was performed in 60 stable adult CF patients. Insulin sensitivity and beta-cell function were measured using the homeostatic model assessment (HOMA2), Stumvoll and oral glucose insulin sensitivity (OGIS) indices.
RESULTS
Forty-two (70%) had normal glucose tolerance (NGT), 10 (17%) impaired glucose tolerance (IGT) and eight (13%) CFRD. There was no difference in insulin sensitivity among the three groups (HOMA2: NGT 280, IGT 250, CFRD 339, P = 0.42; Stumvoll: NGT 0.128, IGT 0.126, CFRD 0.129, P = 0.76; and OGIS: NGT 515, IGT 472, CFRD 472, P = 0.12). Pancreatic beta-cell function (CFRD 50% vs. NGT 67%; P < 0.05) and first-phase insulin secretion were reduced in CFRD (250 vs. NGT 509; P = 0.004). First-phase insulin secretion was inversely correlated with 1-h (r = -0.74; P < 0.0001) and 2-h glucose levels (r = -0.34; P < 0.05). There was no difference in body mass index or poor lung function (forced expiratory volume in 1 s: CFRD 54% vs. NGT 65%; P = 0.43). However, there were more hospital admissions in the CFRD group (three vs. NGT one per patient per year; P < 0.05).
CONCLUSIONS
CFRD is characterized by qualitative and quantitative defects in insulin secretion, but not insulin resistance, and is associated with increased hospital admissions for pulmonary exacerbations.
Publication
Journal: Molecular Neurobiology
October/2/2017
Abstract
There is evidence that immune-inflammatory and oxidative and nitrosative stress (O&NS) pathways play a role in the pathophysiology of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). There is also evidence that these neuroimmune diseases are accompanied by hypothalamic-pituitary-adrenal (HPA) axis hypoactivity as indicated by lowered baseline glucocorticoid levels. This paper aims to review the bidirectional communications between immune-inflammatory and O&NS pathways and HPA axis hypoactivity in ME/CFS, considering two possibilities: (a) Activation of immune-inflammatory pathways is secondary to HPA axis hypofunction via attenuated negative feedback mechanisms, or (b) chronic activated immune-inflammatory and O&NS pathways play a causative role in HPA axis hypoactivity. Electronic databases, i.e., PUBMED, Scopus, and Google Scholar, were used as sources for this narrative review by using keywords CFS, ME, cortisol, ACTH, CRH, HPA axis, glucocorticoid receptor, cytokines, immune, immunity, inflammation, and O&NS. Findings show that activation of immune-inflammatory and O&NS pathways in ME/CFS are probably not secondary to HPA axis hypoactivity and that activation of these pathways may underpin HPA axis hypofunction in ME/CFS. Mechanistic explanations comprise increased levels of tumor necrosis factor-α, T regulatory responses with elevated levels of interleukin-10 and transforming growth factor-β, elevated levels of nitric oxide, and viral/bacterial-mediated mechanisms. HPA axis hypoactivity in ME/CFS is most likely a consequence and not a cause of a wide variety of activated immune-inflammatory and O&NS pathways in that illness.
Publication
Journal: Pediatric Pulmonology
November/14/2010
Abstract
BACKGROUND
Transforming factor beta(1) (TGF-beta(1)) genetic polymorphisms have been identified as a modifier of cystic fibrosis (CF) lung disease severity. However, few data link TGF-beta(1) protein levels and clinical markers of CF lung disease severity.
OBJECTIVE
To determine the association between protein levels of TGF-beta(1) in pediatric CF bronchoalveolar lavage fluid (BALF) and clinical parameters of CF lung disease severity.
METHODS
Total TGF-beta(1) was measured in BALF from 30 pediatric CF patients and 12 non-CF disease controls undergoing clinically indicated flexible bronchoscopy, and compared to four indicators of clinical disease: infection, inflammation, pulmonary function, and recent/recurrent hospitalization.
RESULTS
TGF-beta(1) was elevated in CF BALF compared to non-CF controls (135 +/- 15 pg/ml vs. 57 +/- 10 pg/ml, P < 0.01). In CF BALF, increased TGF-beta(1) was associated with elevated BALF PMN % (r = 0.67, P < 0.01). BALF TGF-beta(1) was increased in CF subjects whose FEV(1) after the completion of antibiotic therapy remained below CF age-normative median values (205.9 +/- 20.5 pg/ml vs. 106.4 +/- 24.0, P = 0.01). BALF TGF-beta(1) was increased in CF children hospitalized in the previous year compared to those not recently hospitalized (169.9 +/- 21.6 pg/ml vs. 107.5 +/- 17.5 pg/ml, P = 0.04). Neither the presence of a bacterial pathogen nor bacterial quantity was associated with BALF TGF-beta(1).
CONCLUSIONS
In CF, BALF TGF-beta(1) is elevated compared to non-CF controls. Increased BALF TGF-beta(1) is associated with neutrophilic inflammation, diminished lung function and recent hospitalization. Further investigation is needed to address mechanisms behind these associations.
Publication
Journal: American Journal of Clinical Nutrition
January/13/2003
Abstract
BACKGROUND
Oxidative stress, as measured by 8-iso-prostaglandin F(2)(alpha) (8-iso-PGF(2)(alpha)), and depleted antioxidant defenses were shown in stable cystic fibrosis (CF) patients. The plasma fatty acid status of CF patients was linked to oxidative stress after respiratory exacerbations.
OBJECTIVE
We examined changes in plasma 8-iso-PGF(2)(alpha), antioxidant defenses, plasma fatty acid status, and clinical markers resulting from short-term antioxidant supplementation.
METHODS
Forty-six CF patients were randomly assigned to either group A [low dose of supplement (10 mg vitamin E and 500 micro g vitamin A)] or group B [high dose of supplement (200 mg vitamin E, 300 mg vitamin C, 25 mg beta-carotene, 90 micro g Se, and 500 micro g vitamin A)]. Plasma concentrations of 8-iso-PGF(2)(alpha), vitamins E and C, beta-carotene, zinc, selenium, and copper; plasma fatty acid composition; erythrocyte glutathione peroxidase (EC 1.11.1.9) and superoxide dismutase (EC 1.15.1.1) activities; lung function; and dietary intake were measured before and after 8 wk of supplementation.
RESULTS
Antioxidant defenses in group B improved, whereas those in group A did not: in groups B and A, the mean (+/- SEM) changes (Delta) in vitamin E were 10.6 +/- 1.5 and -1.9 +/- 0.9 micro mol/L, respectively (P < 0.001), (Delta)beta-carotene were 0.1 +/- 0.04 and -0.01 +/- 0.02 micro mol/L, respectively (P = 0.007), (Delta)selenium were 0.51 +/- 0.10 and -0.09 +/- 0.04 micro mol/L, respectively (P < 0.001), and (Delta)glutathione peroxidase activity were 1.3 +/- 0.3 and -0.3 +/- 0.6 U/g hemoglobin, respectively (P = 0.016). There were no significant differences between the groups in Delta8-iso-PGF(2)(alpha), (Delta)vitamin C, (Delta)fatty acid composition, (Delta)superoxide dismutase activity, (Delta)lung function, or (Delta)white cell count. Within group B, (Delta)beta-carotene correlated with (Delta)percentage of forced vital capacity (r = 0.586, P = 0.005), (Delta)selenium correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.440, P = 0.046), and (Delta)plasma fatty acid concentrations correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.583, P = 0.006) and Delta8-iso-PGF(2)(alpha) (r = 0.538, P = 0.010).
CONCLUSIONS
Whereas increased beta-carotene, selenium, and fatty acid concentrations are linked to improved lung function, increased plasma fatty acid concentrations are linked to oxidative stress. If oxidative stress is deemed to be important to the clinical outcome of CF patients, means of reducing oxidative stress while maintaining a high-fat, high-energy diet must be investigated.
Publication
Journal: Journal of Cystic Fibrosis
August/20/2014
Abstract
BACKGROUND
Induced sputum (IS) is feasible and safe in young CF children and is a readily accessible, non-invasive technique. However, it has not been compared to bronchoalveolar lavage (BAL), the gold standard for diagnosing lower airway infection.
METHODS
We compared bacterial yield from IS and BAL in 11 non-expectorating CF children, aged 3 to 7.4 years. IS samples were obtained in 10/11 cases.
RESULTS
Eight out of ten had the same predominant bacteria cultured from IS and BAL: Pseudomonas aeruginosa and Stenotrophomonas maltophilia[1], Staphylococcus aureus[3], and upper respiratory tract flora [4]. In one, Serratia marcescens and Haemophilus parainfluenzae were cultured from IS alone, whereas in one, non-group B Haemophilus influenzae was cultured from BAL alone.
CONCLUSIONS
As proof of principle, IS samples showed good bacteriologic correlation with BAL. Larger studies are recommended to confirm IS as a clinically valuable tool and measure for early intervention studies in young CF children.
Publication
Journal: BMC Immunology
January/19/2016
Abstract
BACKGROUND
Abnormal immune function is often an underlying component of illness pathophysiology and symptom presentation. Functional and phenotypic immune-related alterations may play a role in the obscure pathomechanism of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). The objective of this study was to investigate the functional ability of innate and adaptive immune cells in moderate and severe CFS/ME patients. The 1994 Fukuda criteria for CFS/ME were used to define CFS/ME patients. CFS/ME participants were grouped based on illness severity with 15 moderately affected (moderate) and 12 severely affected (severe) CFS/ME patients who were age and sex matched with 18 healthy controls. Flow cytometric protocols were used for immunological analysis of dendritic cells, monocytes and neutrophil function as well as measures of lytic proteins and T, natural killer (NK) and B cell receptors.
RESULTS
CFS/ME patients exhibited alterations in NK receptors and adhesion markers and receptors on CD4(+)T and CD8(+)T cells. Moderate CFS/ME patients had increased CD8(+) CD45RA effector memory T cells, SLAM expression on NK cells, KIR2DL5(+) on CD4(+)T cells and BTLA4(+) on CD4(+)T central memory cells. Moderate CFS/ME patients also had reduced CD8(+)T central memory LFA-1, total CD8(+)T KLRG1, naïve CD4(+)T KLRG1 and CD56(dim)CD16(-) NK cell CD2(+) and CD18(+)CD2(+). Severe CFS/ME patients had increased CD18(+)CD11c(-) in the CD56(dim)CD16(-) NK cell phenotype and reduced NKp46 in CD56(bright)CD16(dim) NK cells.
CONCLUSIONS
This research accentuated the presence of immunological abnormalities in CFS/ME and highlighted the importance of assessing functional parameters of both innate and adaptive immune systems in the illness.
Publication
Journal: Respiratory Care
July/8/2009
Abstract
Cystic fibrosis (CF) is a complex genetic disease characterized by lung infections that lead to early morbidity and death. Pathogens that commonly infect the lungs of patients with CF include Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa, and Burkholderia cepacia. Aggressively treating pulmonary infection with antibiotics has contributed to improved survival in patients with CF but has also promoted multiple-drug-resistant bacteria. Other complexities include the ability of bacteria to form biofilms, which makes them more resistant to antibiotics, and emerging pathogens in CF, of which the clinical importance is not yet clear. Increasing evidence of patient-to-patient transmission of CF pathogens led the Cystic Fibrosis Foundation to produce evidence-based infection-control recommendations, which stress 4 principles: standard precautions, transmission-based precautions, hand hygiene, and care of respiratory equipment. Respiratory therapists need to know and follow these infection-control recommendations. Cohorting patients infected with B. cepacia complex is one of several interventions successful at keeping the spread of this pathogen low, but cohorting patients who are infected/colonized with other microbes is controversial, the main argument of which is not being certain of a patient's present respiratory culture status at any given patient visit.
Publication
Journal: BMC Research Notes
November/9/2011
Abstract
BACKGROUND
Blood is a convenient sample and increasingly used for quantitative gene expression measurements with a variety of diseases including chronic fatigue syndrome (CFS). Quantitative gene expression measurements require normalization of target genes to reference genes that are stable and independent from variables being tested in the experiment. Because there are no genes that are useful for all situations, reference gene selection is an essential step to any quantitative reverse transcription-PCR protocol. Many publications have described appropriate genes for a wide variety of tissues and experimental conditions, however, reference genes that may be suitable for the analysis of CFS, or human blood RNA derived from whole blood as well as isolated peripheral blood mononuclear cells (PBMCs), have not been described.
RESULTS
Literature review and analyses of our unpublished microarray data were used to narrow down the pool of candidate reference genes to six. We assayed whole blood RNA from Tempus tubes and cell preparation tube (CPT)-collected PBMC RNA from 46 subjects, and used the geNorm and NormFinder algorithms to select the most stable reference genes. Phosphoglycerate kinase 1 (PGK1) was one of the optimal normalization genes for both whole blood and PBMC RNA, however, additional genes differed for the two sample types; Ribosomal protein large, P0 (RPLP0) for PBMC RNA and Peptidylprolyl isomerase B (PPIB) for whole blood RNA. We also show that the use of a single reference gene is sufficient for normalization when the most stable candidates are used.
CONCLUSIONS
We have identified PGK1 as a stable reference gene for use with whole blood RNA and RNA derived from PBMC. When stable genes are selected it is possible to use a single gene for normalization rather than two or three. Optimal normalization will improve the ability of results from PBMC RNA to be compared with those from whole blood RNA and potentially allows comparison of gene expression results from blood RNA collected and processed by different methods with the intention of biomarker discovery. Results of this study should facilitate large-scale molecular epidemiologic studies using blood RNA as the target of quantitative gene expression measurements.
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