To expand the available set of Baeyer–Villiger monooxygenases (BVMOs), we have created expression constructs for producing 22 Type I BVMOs that are present in the genome of
Rhodococcus jostii
RHA1. ...Each BVMO has been probed with a large panel of potential substrates. Except for testing their substrate acceptance, also the enantioselectivity of some selected BVMOs was studied. The results provide insight into the biocatalytic potential of this collection of BVMOs and expand the biocatalytic repertoire known for BVMOs. This study also sheds light on the catalytic capacity of this large set of BVMOs that is present in this specific actinomycete. Furthermore, a comparative sequence analysis revealed a new BVMO-typifying sequence motif. This motif represents a useful tool for effective future genome mining efforts.
Skeletal muscle lipid metabolism with obesity Hulver, Matthew W; Berggren, Jason R; Cortright, Ronald N ...
American journal of physiology: endocrinology and metabolism,
04/2003, Letnik:
284, Številka:
4
Journal Article
Recenzirano
1 Departments of Physiology,
2 Exercise and Sport Science, Human Performance
Laboratory, 3 Anatomy and Cell Biology, and
4 Surgery, The Brody School of Medicine, East
Carolina University, ...Greenville, North Carolina 27858; and
5 Department of Internal Medicine, Yale University
School of Medicine, New Haven, Connecticut 06510
The objectives
of this study were to 1 ) examine skeletal muscle fatty acid
oxidation in individuals with varying degrees of adiposity and
2 ) determine the relationship between skeletal muscle fatty
acid oxidation and the accumulation of long-chain fatty acyl-CoAs.
Muscle was obtained from normal-weight n = 8; body mass index (BMI) 23.8 ± 0.58 kg/m 2 ,
overweight/obese ( n = 8; BMI 30.2 ± 0.81 kg/m 2 ), and extremely obese ( n = 8; BMI
53.8 ± 3.5 kg/m 2 ) females undergoing abdominal
surgery. Skeletal muscle fatty acid oxidation was assessed in intact
muscle strips. Long-chain fatty acyl-CoA concentrations were measured
in a separate portion of the same muscle tissue in which fatty acid
oxidation was determined. Palmitate oxidation was 58 and 83% lower in
skeletal muscle from extremely obese (44.9 ± 5.2 nmol · g 1 · h 1 )
patients compared with normal-weight (71.0 ± 5.0 nmol · g 1 · h 1 )
and overweight/obese (82.2 ± 8.7 nmol · g 1 · h 1 )
patients, respectively. Palmitate oxidation was negatively
( R = 0.44, P = 0.003) associated with
BMI. Long-chain fatty acyl-CoA content was higher in both the
overweight/obese and extremely obese patients compared with
normal-weight patients, despite significantly lower fatty acid
oxidation only in the extremely obese. No associations were observed
between long-chain fatty acyl-CoA content and palmitate oxidation.
These data suggest that there is a defect in skeletal muscle fatty acid
oxidation with extreme obesity but not overweight/obesity and that the
accumulation of intramyocellular long-chain fatty acyl-CoAs is not
solely a result of reduced fatty acid oxidation.
long-chain fatty acyl-coenzyme A; intramyocellular triacylglycerol; fatty acids
Urbanization is a major global change inducing complex and multiple modifications of landscapes and ecosystems. The spatial distributions of organisms experiencing these modifications will likely ...shift specifically, depending on each species’ response to each environmental modification induced by urbanization. We sampled two ant genera (
Lasius
and
Tetramorium
) at 1248 locations along an urbanization gradient in Lyon, France and used high resolution spatial layers for 18 spatial (e.g., open habitat fragmentation, bioclimatic data and surface temperatures) and temporal (e.g., comparison of Normalized Difference Vegetation Index between 1986 and 2015) environmental variables associated with urbanization. Coupling two different analytical methods (Outlying Mean Index and Boosted Regression Trees), we showed that each species’ distribution was influenced by its own combination of environmental factors. Two morphologically cryptic
Tetramorium
species (
T
. sp.E and
T
. sp.U2) were both highly abundant but with opposite responses to urbanization: while
T
. sp.E was favored by urbanized habitat,
T
. sp.U2 avoided urbanized areas. Among
Lasius
species, we detected 63 occurrences of the invasive ant
Lasius neglectus
, the distribution of which was favored only by embankments along roads. We found that, even at this reduced spatial scale, climatic effects influenced most species and interacted with urbanization factors.
Objectives The study sought to determine whether rapid access to medical care and reperfusion results in a better prognosis in patients with in-hospital compared with out-of-hospital stent thrombosis ...(ST) in patients with ST-segment elevation myocardial infarction (STEMI) in the HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial. Background Whether the prognosis of in-hospital and out-of-hospital ST are similar is uncertain, with conflicting data reported from prior studies. Methods A total of 3,602 STEMI patients undergoing primary percutaneous coronary intervention (PCI) were randomized to bivalirudin (n = 1,800) versus unfractionated heparin (UFH) plus a glycoprotein IIb/IIIa inhibitor (GPI) (UFH+GPI; n = 1,802). Stents were implanted in 3,202 patients, 156 (4.9%) of whom developed Academic Research Consortium definite/probable ST during 3-year follow-up. We investigated the 1-year clinical outcomes after ST in 54 patients with in-hospital ST compared with 102 patients with out-of-hospital ST. Results One year after the ST event, patients with in-hospital compared with out-of-hospital ST had significantly greater mortality (27.8% vs. 10.8%, p < 0.01); most deaths in both groups occurred within 1 week of the ST event. Patients with in-hospital ST also had higher rates of major bleeding (21.2% vs. 6.0%, p < 0.01), but a lower rate of myocardial infarction (56.6% vs. 77.5%, p < 0.01). Subgroup analysis within both in-hospital and out-of-hospital ST groups indicated that subacute ST had the highest mortality. By multivariable analysis, 1-year mortality was significantly increased in patients with in-hospital compared with out-of-hospital ST (adjusted hazard ratio: 4.62, 95% confidence interval: 1.98 to 10.77, p < 0.01). Additional correlates of increased mortality after an ST event included diabetes and randomization to UFH+GPI (vs. bivalirudin). Conclusions Following primary PCI for STEMI, more than one-third of all ST events during 3-year follow-up occurred during the index hospital phase. Mortality and major bleeding were significantly higher after in-hospital ST compared with out-of-hospital ST. (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966 )
Objectives The goal of this study was to characterize the extent and composition of coronary atherosclerosis in patients with diabetes mellitus or the metabolic syndrome (Met Syn) presenting with ...acute coronary syndromes (ACS). Background Diabetes and Met Syn patients have increased rates of major adverse cardiac events (MACE), yet a systematic description of nonculprit lesions for these high-risk groups is incomplete. Methods In the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study, ACS patients underwent 3-vessel quantitative coronary angiography, grayscale, and radiofrequency intravascular ultrasound after successful percutaneous coronary intervention (PCI). Subsequent MACE (cardiac death or arrest, myocardial infarction, or rehospitalization for unstable or progressive angina) were adjudicated to the originally treated culprit versus untreated nonculprit lesions in 3 patient groups: 1) diabetes; 2) Met Syn; and 3) neither. Median length of follow-up was 3.4 years. Results Of 673 patients, 119 (17.7%) had diabetes and 239 (35.5%) had Met Syn. The cumulative 3-year MACE rate was 29.4% in patients with diabetes, 21.3% with Met Syn, and 17.4% with neither (p = 0.03). MACE adjudicated to untreated nonculprit lesions occurred in 18.7%, 11.7%, and 9.7% of patients, respectively (p = 0.06). Nonculprit lesions in diabetes and Met Syn patients were longer and had greater plaque burden, smaller lumen areas, with greater necrotic core and calcium content. Diabetes and Met Syn patients with future MACE had greater necrotic core and calcification compared with the normal cardiometabolic group. Conclusions In this PCI ACS population, patients with diabetes and Met Syn had higher 3-year MACE rates. Lesion length, plaque burden, necrotic core, and calcium content were significantly greater among nonculprit lesions of patients with diabetes and Met Syn, but only necrotic core and calcium were significantly greater in the nonculprit lesions of patients with a future MACE in this exploratory analysis.
Objectives This study investigated coronary artery remodeling patterns associated with clinical outcomes. Background In the prospective, multicenter PROSPECT (Providing Regional Observations to Study ...Predictors of Events in the Coronary Tree: An Imaging Study in Patients With Unstable Atherosclerotic Lesions) study, reported predictors of nonculprit lesion (NCL) major adverse cardiac events (MACE) were an intravascular ultrasound (IVUS) minimal lumen area (MLA) ≤4 mm2 , a plaque burden ≥70%, and a IVUS–virtual histology (VH) thin-cap fibroatheroma (TCFA), but not lesion site remodeling. Methods Overall, 697 consecutive patients with an acute coronary syndrome were enrolled and underwent 3-vessel gray-scale and IVUS-VH; 3,223 NCLs were identified by IVUS. The remodeling index (RI) was calculated as the external elastic membrane area at the MLA site divided by the average of the proximal and distal reference external elastic membrane areas. First, one third of the patients were randomly selected to determine RI cutoffs related to NCL MACE (development cohort). Receiver-operating characteristic analysis showed that there were 2 separate cut points that predicted NCL MACE: RI = 0.8789 and RI = 1.0046 (area under the curve = 0.663). These cut points were used to define negative remodeling as an RI <0.88, intermediate remodeling as an RI of 0.88 to 1.00, and positive remodeling as an RI >1.00. Second, we used the remaining two-thirds of patients to validate these cut points with respect to lesion morphology and clinical outcomes (validation cohort). Results Kaplan-Meier curve analysis in the validation cohort showed that NCL MACE occurred more frequent (and equally) in negative and positive remodeling lesions compared with intermediate remodeling lesions. In this cohort, negative remodeling lesions had the smallest MLA, positive remodeling lesions had the largest plaque burden, and VH TCFA, especially VH TCFA with multiple necrotic cores, was most common in negatively remodeling lesions. Conclusions The present study showed the novel concept that positive and negative lesion site remodeling was associated with unanticipated NCL MACE in the PROSPECT study. (PROSPECT: An Imaging Study in Patients With Unstable Atherosclerotic Lesions PROSPECT; NCT00180466 )
ZnO-based thick-film microvaristors were investigated using impedance spectroscopy. Properties of planar and sandwich structures on alumina and LTCC substrates with different electrode material are ...compared. Experimental characteristics are approximated with electrical equivalent circuit. Fabrication technology influence on proposed model parameters is presented. Temperature dependent behavior is shown. Schottky barrier height was calculated as 0.46
eV and three electrop trap levels with activation energy of 0.17
eV, 0.25
eV and 0.38
eV were found.
In type 1 diabetes, cytokine action on beta cells potentially contributes to beta cell destruction by direct cytotoxicity, inducing Fas expression, and up-regulating class I MHC and chemokine ...expression to increase immune recognition. To simultaneously block beta cell responsiveness to multiple cytokines, we overexpressed suppressor of cytokine signaling-1 (SOCS-1). This completely prevented progression to diabetes in CD8(+) TCR transgenic nonobese diabetic (NOD) 8.3 mice without affecting pancreas infiltration and partially prevented diabetes in nontransgenic NOD mice. SOCS-1 appeared to protect at least in part by inhibiting TNF- and IFN-gamma-induced Fas expression on beta cells. Fas expression was up-regulated on beta cells in vivo in prediabetic NOD8.3 mice, and this was inhibited by SOCS-1. Additionally, IFN-gamma-induced class I MHC up-regulation and TNF- and IFN-gamma-induced IL-15 expression by beta cells were inhibited by SOCS-1, which correlated with suppressed 8.3 T cell proliferation in vitro. Despite this, 8.3 T cell priming in vivo appeared unaffected. Therefore, blocking beta cell responses to cytokines impairs recognition by CD8(+) T cells and blocks multiple mechanisms of beta cell destruction, but does not prevent T cell priming and recruitment to the islets. Our findings suggest that increasing SOCS-1 expression may be useful as a strategy to block CD8(+) T cell-mediated type 1 diabetes as well as to more generally prevent cytokine-dependent tissue destruction in inflammatory diseases.
Objectives This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting ...scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California). Background Multimodality imaging of the first-in-humans trial using a ABSORB BVS scaffold demonstrated at 2 years the bioresorption of the device while preventing restenosis. However, the long-term safety and efficacy of this therapy remain to be documented. Methods In the ABSORB cohort A trial (ABSORB Clinical Investigation, Cohort A ABSORB A Everolimus-Eluting Coronary Stent System Clinical Investigation), 30 patients with a single de novo coronary artery lesion were treated with the fully resorbable everolimus-eluting Absorb scaffold at 4 centers. As an optional investigation in 3 of the 4 centers, the patients underwent multislice computed tomography (MSCT) angiography at 18 months and 5 years. Acquired MSCT data were analyzed at an independent core laboratory (Cardialysis, Rotterdam, the Netherlands) for quantitative analysis of lumen dimensions and was further processed for calculation of fractional flow reserve (FFR) at another independent core laboratory (Heart Flow, Redwood City, California). Results Five-year clinical follow-up is available for 29 patients. One patient withdrew consent after 6 months, but the vital status of this patient remains available. At 46 days, 1 patient experienced a single episode of chest pain and underwent a target lesion revascularization with a slight troponin increase after the procedure. At 5 years, the ischemia-driven major adverse cardiac event rate of 3.4% remained unchanged. Clopidogrel was discontinued in all but 1 patient. Scaffold thrombosis was not observed in any patient. Two noncardiac deaths were reported, 1 caused by duodenal perforation and the other from Hodgkin’s disease. At 5 years, 18 patients underwent MSCT angiography. All scaffolds were patent, with a median minimal lumen area of 3.25 mm2 (interquartile range: 2.20 to 4.30). Noninvasive FFR analysis was feasible in 13 of 18 scans, which yielded a median distal FFR of 0.86 (interquartile range: 0.82 to 0.94). Conclusions The low event rate at 5 years suggests sustained safety after the implantation of a fully bioresorbable Absorb everolimus-eluting scaffold. Noninvasive assessment of the coronary artery with an option of functional assessment could be an alternative to invasive imaging after treatment of coronary narrowing with such a polymeric bioresorbable scaffold. (ABSORB Clinical Investigation, Cohort A ABSORB A Everolimus-Eluting Coronary Stent System Clinical Investigation ABSORB; NCT00300131 )
Direct interaction between auto-reactive CTL and specific peptide–MHC class I complexes on pancreatic beta cells is critical in mediating beta cell destruction in type I diabetes. We used mice with ...genetic modifications in three major pathways used by CTL, perforin, Fas and pro-inflammatory cytokines to assess the relative contribution of these mechanisms to beta cell death. In vitro-activated ovalbumin (OVA)-specific CTL, from OT-I TCR-transgenic mice, specifically killed transgenic beta cells expressing OVA (from RIP-mOVA mice) in a 16-h cytotoxicity assay. Perforin-deficient CTL had a reduced ability to kill OVA-expressing islets in vitro (22.1 ± 3.8%) compared with wild-type CTL (71.4 ± 4.6%). Fas-deficient islets were only slightly protected from wild-type CTL but were completely protected from the residual killing observed with perforin-deficient CTL. Residual cytotoxicity in perforin-deficient CTL was also prevented by overexpression of SOCS-1, which blocks multiple cytokine signaling pathways. It was also prevented by pre-incubation with anti-tumor necrosis factor-alpha (anti-TNFα) antibody or by blocking IFNγ responsiveness through expressing a dominant negative IFNγ receptor. Perforin-deficient CTL produced IFNγ and TNFα that was shown to directly induce islet Fas expression during the assays. This suggests that Fas-deficiency, SOCS-1 overexpression and blockade of IFNγ and TNFα all protect beta cells from residual cytotoxicity of perforin-deficient CTL by blocking Fas upregulation. These findings indicate that wild-type CTL destroy antigen-expressing islets via a perforin-dependent mechanism. However, in the absence of perforin, the Fas/FasL pathway provides an alternative mechanism dependent on islet cell Fas upregulation by cytokines IFNγ and TNFα.
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