The present review is based mainly on papers published between 2000 and 2011 and gives information about the properties of the carotenoid lycopene in chemical and biological systems and its possible ...role in preventing cardiovascular diseases (CVD). The main aim of this report is to highlight its role as an antioxidant, also reported are bioactive properties that may influence the development of foam cells and protection against endothelial cell damage. The paper will also examine recent observations that lycopene may improve blood flow and reduce inflammatory responses. Lycopene possesses antioxidant properties in vitro, and some epidemiological studies have reported protective effects against the progression of CVD. The oxidation of human low density lipoproteins (LDL) is a fundamental mechanism in the initiation of atherosclerosis. A beneficial role of lycopene as antioxidant in the prevention of CVD is suggested but the data are still controversial. Lycopene is believed to be the most potent carotenoid antioxidant in vitro. Tissue culture experiments and animal studies support potential cardioprotective effects for lycopene and other carotenoids in the blood. Most studies showed beneficial effects of lycopene to individuals who are antioxidant-deficient like elderly patients, or humans exposed to higher levels of oxidative stress like smokers, diabetics, hemodialysis patients and acute myocardial infarction patients. By defining the right population and combining antioxidant potentials of lycopene with vitamins and other bioactive plant compounds, the beneficial role of lycopene in CVD can be clarified in future studies.
► Carotenoids did not show DPPH-radical scavenging activity. ► Lycopene was the most effective carotenoid in bleaching the ABTS radical cation. ► Of the carotenes, solely lycopene presented ferric ...reducing activity. ► Ketocarotenoids were most effective in scavenging peroxyl radicals. ► Weighted averages of antioxidant activities were calculated to summarise effects.
The purpose of this study was to assess the antioxidant activity of carotenes and xanthophylls measured by various methods, compared to α-tocopherol, BHA and BHT. Four assays were selected to achieve a wide range of technical principles. Besides αTEAC, which uses ABTS
+
radical cation, ferric reducing activity (measured by using FRAP assay), and 2,2-diphenyl-1-picrylhydrazyl (DPPH
) scavenging assay were used. In addition, a luminol-chemiluminescence based peroxyl radical scavenging capacity (LPSC) assay, was used. Most of the compounds showed significant differences in their activity of scavenging radicals depending on the assay used. Of the 22 compounds tested, only a few such as lutein, zeaxanthin and capsanthin gave comparable results in the various assays. Surprisingly, in contrast to α-tocopherol, BHA and BHT, carotenoids did not show any DPPH
scavenging activity. To standardise the relative contribution of the assays used, weighted means of the values obtained in αTEAC, FRAP, DPPH and LPSC assay were calculated. This strategy was used to assess the antioxidant capacity of several juices and oil samples. The highest lipophilic antioxidant capacity in all assays was observed for sea buckthorn berry juice, followed by tomato juice, carrot juice and orange juice. Within the oil samples, the order of antioxidant capacity depended on the assay used.
Conjugated organoboranes have emerged as attractive hybrid materials for optoelectronic applications. Herein, a highly efficient, environmentally benign catalytic B–C bond formation method is ...presented that uses organosilicon compounds, dibromoboranes, and the metal-free organocatalyst Me3SiNTf2. This Si/B exchange approach has been successfully applied to the synthesis of arylborane molecules 4a–c, oligomers 8a,b, and polymers 8a′,b′. Photophysical investigations, supported by TD-DFT calculations, reveal highly effective π-conjugation in thienyl- and furylborane species; the latter are also highly emissive.
Recurrent varicosities after endovascular laser ablation (EVLA) of the great saphenous vein (GSV) are frequently due to varicose transformed, initially unsealed major ascending tributaries of the ...saphenofemoral junction (SFJ). Preventive ablation of these veins, especially the anterior accessory saphenous vein, is discussed as an option, along with flush occlusion of the GSV. However, few related data exist to date.
A consecutive case series of 278 EVLA procedures of the GSV for primary varicosis in 213 patients between May and December 2019 was retrospectively reviewed. The ablations were performed with a 1470 nm dual-ring radial laser and always included flush occlusion of the GSV, and concomitant ablation of its highest ascending tributaries by additional cannulation and ablation when this seemed anatomically appropriate. The initial technical success, comprising occlusion of the GSV and its major tributaries, was set as the primary endpoint. Possible determinants were explored using downstream multiple logistic regression analysis.
The early technical success was 92.8%, with the GSV occluded in 99.6% and the highest ascending SFJ tributary, if present, in 92.4%. Additional ablations of ascending tributaries were performed in 171 cases (61.5%), the latter being associated with success (OR 10.39; 95% CI 3.420-36.15; p < 0.0001). Presence of anterior as opposed to posterior accessory saphenous vein was another positive predictor (OR 3.959; 95% CI 1.142-13,73; p = 0.027), while a confluence of the tributary in the immediate proximity to the SFJ had a negative impact (OR 0.2253; 95% CI 0.05456-0.7681; p = 0.0253). An endothermal heat-induced thrombosis (EHIT) ≥ grade 2 was observed in three cases (1.1%).
A co-treatment of the tributaries is feasible and could improve the technical success of EVLA if a prophylactic closure of these veins is desired, especially if their distance to the SFJ is short. Its effect on the recurrence rate needs further research.
Aim To assess the feasibility and technical success of endovenous laser ablation (EVLA) of recurrent varicose veins arising from the former sapheno-femoral junction (SFJ). Methods We retrospectively ...analyzed all EVLA procedures treated in our institution by one surgeon between March 2019 and April 2020 and selected all consecutive cases with SFJ recurrence occuring after surgical high ligation and stripping or endovenous thermal ablation for incompetence of the great saphenous vein (GSV) in superficial venous insufficiency. The feasibility, technical success as determined by duplex ultrasound on the postoperative visit, complications and rate of endothermal heat-induced thrombosis (EHIT) were recorded. A subgroup definition was performed based on sonographic morphology of the recurrence and resulting strategy of ablation. Results Thirty-five limbs with SFJ recurrence in 34 patients were treated with EVLA in order to shut down the highest refluxing point. In 22 interventions, it was required to switch off a short stump or a neovascularization by direct puncture (Subgroup 1). In 13 treatments, the presence of residual GSV segments, or persistent, varicose transformed major tributaries like the anterior accessory great saphenous vein, enabled cannulation and advancing the laser fiber from distal to the former SFJ (Subgroup 2). The EVLA procedures could be successfully carried out in all 35 cases. There were no major complications, no thromboembolism or EHIT, and no local groin complications. In one case, the patient developed a phlebitic response that required temporary medication. Technical success was achieved with 34/35 treatments (97.1%). When comparing the subgroups, the morphological pattern of the SFJ recurrence and the resulting technique of puncture, cannulation and ablation did not influence the result. Conclusions The results of this case series suggest that SFJ recurrences can also be successfully treated in situations where there are tortuous or short stumps that require direct puncture and ablation.
Fanconi anemia (FA) is a recessive syndrome characterized by progressive fatal BM failure and chromosomal instability. FA cells have inactivating mutations in a signaling pathway that is critical for ...maintaining genomic integrity and protecting cells from the DNA damage caused by cross-linking agents. Transgenic expression of the implicated genes corrects the phenotype of hematopoietic cells, but previous attempts at gene therapy have failed largely because of inadequate numbers of hematopoietic stem cells available for gene correction. Induced pluripotent stem cells (iPSCs) constitute an alternate source of autologous cells that are amenable to ex vivo expansion, genetic correction, and molecular characterization. In the present study, we demonstrate that reprogramming leads to activation of the FA pathway, increased DNA double-strand breaks, and senescence. We also demonstrate that defects in the FA DNA-repair pathway decrease the reprogramming efficiency of murine and human primary cells. FA pathway complementation reduces senescence and restores the reprogramming efficiency of somatic FA cells to normal levels. Disease-specific iPSCs derived in this fashion maintain a normal karyotype and are capable of hematopoietic differentiation. These data define the role of the FA pathway in reprogramming and provide a strategy for future translational applications of patient-specific FA iPSCs.
Bending, in addition to compression, is recognized to be a common loading pattern in long bones in animals. However, due to the technical difficulty of measuring bone deformation in humans, our ...current understanding of bone loading patterns in humans is very limited. In the present study, we hypothesized that bending and torsion are important loading regimes in the human tibia. In vivo tibia segment deformation in humans was assessed during walking and running utilizing a novel optical approach. Results suggest that the proximal tibia primarily bends to the posterior (bending angle: 0.15°-1.30°) and medial aspect (bending angle: 0.38°-0.90°) and that it twists externally (torsion angle: 0.67°-1.66°) in relation to the distal tibia during the stance phase of overground walking at a speed between 2.5 and 6.1 km/h. Peak posterior bending and peak torsion occurred during the first and second half of stance phase, respectively. The peak-to-peak antero-posterior (AP) bending angles increased linearly with vertical ground reaction force and speed. Similarly, peak-to-peak torsion angles increased with the vertical free moment in four of the five test subjects and with the speed in three of the test subjects. There was no correlation between peak-to-peak medio-lateral (ML) bending angles and ground reaction force or speed. On the treadmill, peak-to-peak AP bending angles increased with walking and running speed, but peak-to-peak torsion angles and peak-to-peak ML bending angles remained constant during walking. Peak-to-peak AP bending angle during treadmill running was speed-dependent and larger than that observed during walking. In contrast, peak-to-peak tibia torsion angle was smaller during treadmill running than during walking. To conclude, bending and torsion of substantial magnitude were observed in the human tibia during walking and running. A systematic distribution of peak amplitude was found during the first and second parts of the stance phase.
Background Radial head arthroplasty is considered the treatment of choice for unreconstructable radial head fractures in the acute fracture situation. Although short-term results in the current ...literature are promising, replacement of the radial head remains controversial as long-term results are still missing. We report our 8.8-year results after treatment with a bipolar radial head prosthesis by Judet. Materials and methods In our department, 19 patients were treated with bipolar radial head arthroplasty between 1997 and 2001. Seventeen of these patients—14 men and 3 women—were examined retrospectively after 106 months (range, 78-139). Of these, 9 patients were treated primarily, 7 patients secondarily, and 1 because of a tumor. Results On the Mayo Elbow Performance Score, 6 patients achieved excellent results, 10 good, and one fair. The mean DASH score was 9.8 (range, 0-34). No differences were seen between primary and secondary implantation. Flexion averaged 124° (range, 110-150°), the extension deficit was 21° (range, 0-40°), pronation 64° (range, 30-90°), and supination 64° (range, 30-90°). The following complications were seen: 2 dislocations and 8 cases of degenerative changes of the capitellum, 1 with severe erosion. Signs of ulnohumeral arthrosis were found in 12 patients. No evidence of loosening, radiolucencies, or proximal bone resorption was detected. Conclusion Despite major primary complications and high incidence of radiographic signs of degenerative changes after 8.8 years, mainly good clinical results were achieved with Judet's bipolar prosthesis.
Oxide/silver/oxide multilayers as semitransparent top electrode for small molecule organic solar cells (OSCs) are presented. It is shown that two oxide layers sandwiching a central metal layer ...greatly improve the stability and lifetime of the organic solar cell. Thermally evaporated MoO3, WO3, or V2O5 layers are employed as an interlayer for subsequent silver deposition and significantly change the morphology of the ultrathin silver layer, improving charge extraction and electrodes series resistance. The transmittance of the electrode is increased by introducing oxide or oxide and organic multilayers as capping layer, which leads to higher photocurrent generation in the absorber layer. Application of 1 nm MoO3/11 nm Ag/10 nm MoO3/50 nm Alq3 multilayer electrodes in OSCs lead to an efficiency of 2.6% for a standard ZnPc:C60 cell, showing superior performance compared to devices with pure silver top contacts. The device lifetime is also strongly increased. MoO3 layers can saturate and stabilize the inner and outer metal surface, passivating it against most of the degradation mechanisms. With such an oxide/silver/oxide multilayer electrode, the time until the glass encapsulated OSC is degraded to 80% of its starting efficiency is enhanced from 86 h to approximately 4500 h compared to an OSC without an oxide interlayer.
A stable semitransparent thin silver top contact for organic solar cells is fabricated by sandwiching it between thermally evaporated MoO3 layers. By using a MoO3 interlayer, the morphology of the Ag electrode is improved, leading to better charge collection. The sandwich increases the electrode transmittance, photocurrent generation, and lifetime. With this, more efficient solar cells with lifetimes of 4500 h are achieved.
Efficient electrical doping of organic semiconductors is a necessary prerequisite for the fabrication of high performance organic electronic devices. In this work, we study p-type doping of ...poly(3-hexylthiophene) (P3HT) with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) spin-cast from two different solvents. Using electron diffraction, we find strong dopant-induced π–π-stacking for films from the solvent chloroform, but not from chlorobenzene. This image is confirmed and expanded by the analysis of vibrational features of P3HT and polaron absorptions using optical spectroscopy. Here, a red-shifted polaron absorption is found in doped films from chloroform, caused by a higher conjugation length of the polymer backbone. These differences result in a higher conductivity of films from chloroform. We use optical spectroscopy on the corresponding blend solutions to shed light on the origin of this effect and propose a model to explain why solutions of doped P3HT reveal more aggregation of charged molecules in chlorobenzene, whereas more order is finally observed in dried films from chloroform. Our study emphasizes the importance of solvent parameters exceeding the bare solubility of pure dopant and host material for the preparation of highly conductive doped films.
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