Heme released from heme-binding proteins on internal hemorrhage, hemolysis, myolysis, or other cell damage is highly toxic due to oxidative and proinflammatory effects. Complex formation with ...hemopexin, the high-affinity heme-binding protein in plasma and cerebrospinal fluid, dampens these effects and is suggested to facilitate cellular heme metabolism. Using a ligand-affinity approach, we purified the human hemopexin-heme receptor and identified it as the low-density lipoprotein receptor-related protein (LRP)/CD91, a receptor expressed in several cell types including macrophages, hepatocytes, neurons, and syncytiotrophoblasts. Binding experiments, including Biacore analysis, showed that hemopexin-heme complex formation elicits the high receptor affinity. Uptake studies of radio-labeled hemopexin-heme complex in LRP/CD91-expressing COS cells and confocal microscopy of the cellular processing of fluorescent hemopexin-heme complex established the ability of LRP/CD91 to mediate hemopexin-heme internalization resulting in cellular heme uptake and lysosomal hemopexin degradation. Uptake of hemopexin-heme complex induced LRP/CD91-dependent heme-oxygenase 1 mRNA transcription in cultured monocytes. In conclusion, hemopexin-heme complexes are removed by a receptor-mediated pathway showing striking similarities to the CD163-mediated haptoglobin-hemoglobin clearance in macrophages. Furthermore, the data indicate a hitherto unknown role of LRP/CD91 in inflammation. (Blood. 2005; 106:2572-2579)
•The PdCu alloy formation during reduction was proven.•The presence of Cu+ and Cu0 species on the catalysts surface was confirmed by XPS.•High selectivity of Pd–Cu catalyst to hydrogen is explained ...by alloy formation.
This paper deals with the study of the bimetallic Pd–Cu and monometallic Cu catalyst in steam reforming of methanol. FTIR spectroscopy, X-ray diffraction (XRD) and XPS techniques were used to characterize both mono and bimetallic catalysts. This study presents evidence of Pd–Cu formation in copper catalysts supported on spinel structure ZnAl2O4 during reduction in 5%H2–95%Ar mixture at 300°C in the presence of palladium. The intermetallic compound is formed by a spillover effect between Pd and Cu.
An assessment of operating conditions in a baffled fish passage with pool dimensions of 2.2 × 3.0 m, and 180° horizontally turning pools, was carried out using numerical computations and a site ...survey of water flow velocity distribution. Velocity was measured with a PMS electromagnetic flowmeter and a hydrometric current meter in representative cross-sections of the fish passage in the pool centres and in the baffle barrier cross-section area. Numerical computations were also performed for two alternative baffle locations in the fishway. One reflected the actual conditions, and the other was an alternative arrangement designed to improve hydraulic conditions for fish migration. The numerical model used the Large Eddy Simulation (LES) method, which makes it possible to detect large vortexes. The study pays close attention to the velocity field analysis as well as the distribution and sizes of vortexes in the turning pool of the culvert. The results of numerical computations and the site survey show high consistency, and the proposed baffle placement modification significantly improves flow conditions, especially in the entry section of the passage.
A series of TiO
2
photocatalysts loaded with various metals (Pt, Pd, Ni, and Cu) were prepared by using the wet impregnation method. Their physicochemical properties were studied by using XRD, BET, ...TPR-H
2
, FTIR and TPD-NH
3
/CO
2
techniques. The photocatalytic activity of samples was investigated in the gas-phase reduction of carbon dioxide under continuous flow operation mode. Among all investigated catalysts, the Pt and Ni were the most active in terms of the formation rate of methanol. In general, the photocatalytic activity of modified TiO
2
decreased with increasing metal loading and reaction time. The reversible deactivation of photocatalysts was associated with the covering of TiO
2
surface by the reaction products.
The activity of monometallic Pd, Ru, Ni and Cu catalysts supported on spinel ZnAl
2
O
4
for water gas shift reaction (WGS) was investigated. The physicochemical properties of each catalyst was ...studied by XRD, TPR, BET and chemisorption methods. The highest activity was obtained for Cu/ZnAl
2
O
4
among the catalysts tested. The activation process carried out in a reducing atmosphere 5%H
2
-95%Ar in the case of Cu/ZnAl
2
O
4
system lead to the catalytic activity improvement. In the case of copper catalysts, the water gas shift reaction proceeded by the redox surface mechanism between Cu
0
/Cu
+
. The PdZn alloy formation after reduction at 350°C was shown.
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•Esculin, hesperidin, or thyme oil were encapsulated in biopolymer (CMC, ALG, CHIT, and GEL) macro- and microparticles.•The in vitro release profiles were elaborated under simulated ...gastric and intestinal conditions.•The obtained hydrogels enabled prolonged payload release (~90–300 min) under simulated gastrointestinal conditions.•Various kinetic models were applied to determine the payload release and loading mechanisms.•The release mechanism of the studied particles was dominated by super case II transport.
Understanding the factors that control biopolymeric carriers' drug release profiles is essential to determine their applicability as drug delivery systems. We attempted to evaluate the relationships between the kinetics of the release of selected phytopharmaceuticals from a series of polysaccharide-based particles and the physicochemical properties of the resulting macro- and microcarriers, including alginate (ALG)- and carboxymethyl cellulose (CMC)-based particles with gelatine (GEL) or chitosan (CHIT) shells. Hydrogel beads (612–1080 μm) and microparticles (8.5–44 μm) were successfully loaded with esculin (ESC), hesperidin (HES), or thyme oil (TO), their morphology was elucidated by scanning electron microscopy (SEM), and the encapsulation efficiency was determined by spectrophotometry. The hydrogel carriers exhibited a prolonged payload release (~90–300 min) under simulated gastrointestinal conditions, dependent on the coating type and pH environment. The variations in the particle composition influenced the drug release profiles, which were directly related to the carrier composition and payload characteristics. The Korsmeyer-Peppas and Peppas-Sahlin models, as well as a newly proposed hybrid model, provided the most appropriate description of the payload release from our particles when considered separately under the simulated gastric and intestinal conditions. Additionally, the Gallagher-Corrigan model was selected as the adequate one for predicting the consecutive payload release under those conditions. Establishing the most desirable mathematical model to predict the release profiles facilitated our comprehensively study the mechanism and release kinetics from multiple types of polysaccharide-based delivery vehicles loaded with phytopharmaceuticals possessing different structural and chemical features (i.e., water solubility and log P).
This study tests the hypothesis that the mannose receptor (MR/CD206), which is expressed primarily by macrophages and dendritic cells, can be found in a soluble form (sMR, sMR) in human serum. ...Furthermore, we wished to establish and validate an enzyme-linked immunosorbent assay (ELISA) for sMR and to perform initial studies exploring the potential of sMR as a biomarker.
Western blotting identified a single band of approximately 170 kDa in human serum, and MALDI MS/MS of the purified protein confirmed it to be sMR. An ELISA was established and validated with a measurement range of 1–256 µg/L.
The 95% reference interval was 0.10–0.43 mg/L based on measurements of serum samples from healthy individuals (n=217). Samples from hospitalised patients (n=219) revealed that more than 50% of patients had concentrations above 0.43 mg/L. Very high concentrations (up to 6.2 mg/L) were observed in critically ill patients with sepsis and/or severe liver disease.
This study documents, for the first time, the presence of sMR in human serum and describes an optimised ELISA suitable for quantitative measurements. Levels of sMR are strongly elevated in several disease states, including sepsis and liver disease, and the protein therefore shows promise as a new biomarker.
ObjectivesPakistan has a hepatitis C virus (HCV) infection prevalence of 6%–9% and aims to achieve World Health Organisation (WHO) targets for elimination of HCV by the year 2030. We aim to evaluate ...the potential cost-effectiveness of a reference laboratory-based (centralised laboratory testing; CEN) confirmatory testing approach versus a molecular near-patient point-of-care (POC) confirmatory approach to screen the general population for HCV in Pakistan.Study designWe used a decision tree-analytic model from a governmental (formal healthcare sector) perspective.Study settingIndividuals were assumed to be initially screened with an anti-HCV test at home, followed by POC nucleic acid test (NAT) at nearby district hospitals or followed by NAT at centralised laboratories.ParticipantsWe included the general testing population for chronic HCV in Pakistan.InterventionScreening with an anti-HCV antibody test (Anti-HCV) followed by either POC NAT (Anti-HCV-POC), or reference laboratory NAT (Anti-HCV-CEN), was compared, using data from published literature and the Pakistan Ministry of Health.MeasuresOutcome measures included: number of HCV infections identified per year, percentage of individuals correctly classified, total costs, average costs per individual tested, and cost-effectiveness (assessed as cost per additional HCV infection identified). Sensitivity analysis was also performed.ResultsAt a national level (25 million annual screening tests), the Anti-HCV-CEN strategy would identify 142 406 more HCV infections in 1 year and increase correct classification of individuals by 0.57% compared with the Anti-HCV-POC strategy. The total annual cost of HCV testing was reduced using the Anti-HCV-CEN strategy by US$7.68 million (US$0.31/person). Thus, incrementally, the Anti-HCV-CEN strategy costs less and identifies more HCV infections than Anti-HCV-POC. The incremental difference in HCV infections identified was most sensitive to the probability of loss to follow-up (for POC confirmatory NAT).ConclusionsAnti-HCV-CEN would provide the best value for money when scaling up HCV testing in Pakistan.
The impact of heterogeneous catalytic systems, which are based on rare earth metals, on the properties of biodiesel produced via the transesterification process in a stationary reactor (autoclave) ...was thoroughly investigated. The physicochemical attributes, including the specific surface area, were analyzed employing the Brunauer–Emmett–Teller (BET) method. The basicity and acidity levels of the catalytic systems were evaluated through temperature-programmed desorption of ammonia and carbon dioxide (TPD-NH3, TPD-CO2), respectively. Furthermore, High-Performance Liquid Chromatography (HPLC) analysis facilitated the assessment of triglyceride conversion and the determination of methyl ester (FAME) selectivity within these processes. Our findings indicate that catalytic systems augmented with lanthanum showcased superior performance. A significant correlation was discerned between the conversion and selectivity to methyl esters and both the specific surface area and the acidity and basicity properties of the catalytic systems under study. These results underscore the crucial role that the physicochemical characteristics of catalytic systems play in optimizing the transesterification process, thereby enhancing the quality of the produced biodiesel. This study contributes valuable insights into the development of more efficient and effective biodiesel production methodologies, highlighting the potential of rare earth metal-based catalysts in renewable energy technologies.
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