cell harvesting Dotaz Zobrazit nápovědu
Úvod: V koronární chirurgii představuje endoskopický odběr vena safena magna (EVH) moderní techniku, která při zachování kvality získaného žilního štěpu významně snižuje výskyt ranných a neurologických komplikací, ve srovnání s tradiční technikou odběru vena safena magna. Metody: Endoskopický odběr vena safena magna (EVH) byl proveden u 60 nemocných indikovaných k chirurgické revaskularizaci myokardu v období VII-XII/2005. K odběru bylo použito instrumentárium Vasoview 6™ (Guidant, Europe S.A., Belgium). Sedmý pooperační den byl hodnocen u všech nemocných v souboru výskyt ranných a neurologických komplikací a reziduálních otoků po odběru VSM. Výsledky: Střední věk v souboru byl 67,4 ± 11,2 roku, muži dominovali (68 %) a u 39 nemocných (63 %) byl přítomen minimálně jeden rizikový faktor rozvoje ranných komplikací spojených s odběrem vena safena magna. Průměrný počet odebraných žilních štěpů byl 2,0 ± 1,2 a průměrný odběrový čas byl 46,2 ± 7,4 minut. Konverze na tradiční odběr vena safena byla nutná u 1 nemocného (1,7 %). Při hodnocení sedmý pooperační den byl přítomen ranný hematom 31 nemocných (51 %). Nebyly zaznamenány žádné jiné ranné a neurologické komplikace. U 7 nemocných (12 %) byl přítomen reziduální otok dolní končetiny. Kvalita získaných žilních štěpu byla srovnatelná se štěpy odebranými tradiční technikou. Závěr: EVH významně snižuje výskyt ranných a neurologických komplikací spojených s odběrem vena safena magna. Odběr je možno bezpečně provést i u nemocných s rizikovými faktory jako jsou diabetes mellitus, ischemická choroba dolních končetin, obezita či dlouhodobá imunosupresivní léčba. Kvalita žilních štěpů a časová náročnost odběru je plně srovnatelná s tradiční technikou odběru VSM.
Background: Traditional great saphenous vein harvest for coronary artery bypass grafting is associated with a significant risk of impaired wound healing. Endoscopic saphenous vein harvesting (EVH) has been introduced in an effort to reduce the incidence of leg-wound complications, whereas the histological quality and long-term patency of harvested grafts are comparable with grafts harvested by means of traditional technique. Methods: From July to December 2005, EVH was performed in a group of 60 patients employing the Vasoview 6™ system (Guidant, Europe S.A., Belgium). Patients were evaluated on 7th postoperative day for wound healing disturbances, residual leg oedema and saphenous neuropathy. Results: The mean age was 67.4 ± 11.2 years, male patients dominated (68%). At least one independent risk factor of legwound disturbances such as obesity, diabetes, peripheral vascular disease and female gender, was presented in 39 patients (63%). The mean number of harvested venous grafts was 2.0 ± 1.2 and the mean total vein harvesting time was 46.2 ± 7.4. In one case (1.7%), EVH was converted to the traditional harvesting technique due to superficial course of the great saphenous vein. The presence of wound haematoma was noted in 31 patients (51%). No other wound disturbances such as wound infection, wound dehiscence, skin necrosis, lymphatic wound drainage, nor saphenous neuropathy were recorded in the group of patients. The leg oedema associated with EVH was presented in 7 patients (12%). Conclusions: EVH is a safe method associated with a significant reduction of leg-wound complications, residual leg oedema and saphenous neuropathy. EVH should become method of choice, particularly in the presence of independent risk factors of leg-wound disturbances. The quality and the harvesting time of harvested grafts were comparable to grafts harvested by means of the traditional harvesting technique.
Light-harvesting capacity was investigated in six species of aerobic anoxygenic phototrophic (AAP) bacteria using absorption spectroscopy, fluorescence emission spectroscopy, and pigment analyses. Aerobically grown AAP cells contained approx. 140-1800 photosynthetic reaction centers per cell, an order of magnitude less than purple non-sulfur bacteria grown semiaerobically. Three of the studied AAP species did not contain outer light-harvesting complexes, and the size of their reaction center core complexes (RC-LH1 core complexes) varied between 29 and 36 bacteriochlorophyll molecules. In AAP species containing accessory antennae, the size was frequently reduced, providing between 5 and 60 additional bacteriochlorophyll molecules. In Roseobacter litoralis, it was found that cells grown at a higher light intensity contained more reaction centers per cell, while the size of the light-harvesting complexes was reduced. The presented results document that AAP species have both the reduced number and size of light-harvesting complexes which is consistent with the auxiliary role of phototrophy in this bacterial group.
- MeSH
- aerobióza MeSH
- Alphaproteobacteria chemie metabolismus MeSH
- bakteriochlorofyly metabolismus MeSH
- fotosyntetická reakční centra (proteinové komplexy) chemie metabolismus MeSH
- fototrofní procesy MeSH
- Gammaproteobacteria chemie metabolismus MeSH
- světlosběrné proteinové komplexy chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: The volume effect of fat grafting is highly dependent on the presence of viable adipocytes and other nucleated cells within the lipoaspirate. We suspected that one of the crucial factors influencing cell viability is the negative pressure applied during the fat graft harvesting and the suitability of various harvest sites when compared to others. Despite much discussion, there is no consensus on the optimal negative pressure or the best site for harvesting so we designed an experiment to test this. METHODS: Fat graft taken under low negative pressure (- 200 mmHg) or high negative pressure (- 700 mmHg) from the thigh or abdominal regions from 21 healthy human donors was evaluated. The principal variables studied were: a) total number and viability of nucleated cells, b) liposuction duration and c) blood admixture. Other variables studied were body mass index, the impact of age and enzymatic digestion. RESULTS: The absolute number and viability of nucleated cells and the blood admixture did not differ significantly between lipoaspirates obtained under different vacuum conditions or from different regions. The time taken to acquire the same volume of lipoaspirate was significantly increased using low negative pressure. The time taken to collect cells in the thigh region significantly increased with increasing BMI but this correlation was not found when harvesting in the abdominal region. The BMI and age did not impact the results in any of the measured variables. The enzymatic digestion rate was independent of the negative pressure used to harvest. CONCLUSION: Our results indicate that neither the negative pressure used nor the area chosen has any significant influence on the viability and yield of harvested cells. The time taken to obtain lipoaspirate using low pressure is significantly longer than when using high pressure. No significant difference was found in the value of blood admixture using different vacuum pressures, and no correlation exists between the body mass index and the cell viability or age of the patients and the time of liposuction. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .
- MeSH
- lidé MeSH
- lipektomie * MeSH
- odběr tkání a orgánů MeSH
- tuková tkáň MeSH
- tukové buňky MeSH
- viabilita buněk MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Survival of phototrophic organisms depends on their ability to collect and convert enough light energy to support their metabolism. Phototrophs can extend their absorption cross section by using diverse pigments and by tuning the properties of these pigments via pigment-pigment and pigment-protein interaction. It is well known that some cyanobacteria can grow in heavily shaded habitats by utilizing far-red light harvested with far-red-absorbing chlorophylls d and f. We describe a red-shifted light-harvesting system based on chlorophyll a from a freshwater eustigmatophyte alga Trachydiscus minutus (Eustigmatophyceae, Goniochloridales). A comprehensive characterization of the photosynthetic apparatus of T. minutus is presented. We show that thylakoid membranes of T. minutus contain light-harvesting complexes of several sizes differing in the relative amount of far-red chlorophyll a forms absorbing around 700 nm. The pigment arrangement of the major red-shifted light-harvesting complex is similar to that of the red-shifted antenna of a marine alveolate alga Chromera velia. Evolutionary aspects of the algal far-red light-harvesting complexes are discussed. The presence of these antennas in eustigmatophyte algae opens up new ways to modify organisms of this promising group for effective use of far-red light in mass cultures.
- MeSH
- biologické pigmenty metabolismus MeSH
- diuron MeSH
- fluorescenční spektrometrie MeSH
- Heterokontophyta metabolismus účinky záření MeSH
- membránové proteiny metabolismus MeSH
- sladká voda * MeSH
- světlo * MeSH
- světlosběrné proteinové komplexy metabolismus MeSH
- teplota MeSH
- tylakoidy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
Photosynthetic eukaryotes whose cells harbor plastids originating from secondary endosymbiosis of a red alga include species of major ecological and economic importance. Since utilization of solar energy relies on the efficient light-harvesting, one of the critical factors for the success of the red lineage in a range of environments is to be found in the adaptability of the light-harvesting machinery, formed by the proteins of the light-harvesting complex (LHC) family. A number of species are known to employ mainly a unique class of LHC containing red-shifted chlorophyll a (Chl a) forms absorbing above 690 nm. This appears to be an adaptation to shaded habitats. Here we present a detailed investigation of excitation energy flow in the red-shifted light-harvesting antenna of eustigmatophyte Trachydiscus minutus using time-resolved fluorescence and ultrafast transient absorption measurements. The main carotenoid in the complex is violaxanthin, hence this LHC is labeled the red-violaxanthin-Chl a protein, rVCP. Both the carotenoid-to-Chl a energy transfer and excitation dynamics within the Chl a manifold were studied and compared to the related antenna complex, VCP, that lacks the red-Chl a. Two spectrally defined carotenoid pools were identified in the red antenna, contributing to energy transfer to Chl a, mostly via S2 and hot S1 states. Also, Chl a triplet quenching by carotenoids is documented. Two separate pools of red-shifted Chl a were resolved, one is likely formed by excitonically coupled Chl a molecules. The structural implications of these observations are discussed.
- MeSH
- chlorofyl a * MeSH
- Chlorophyta fyziologie MeSH
- fluorescenční spektrometrie metody MeSH
- Heterokontophyta fyziologie MeSH
- plastidy MeSH
- přenos energie fyziologie MeSH
- Rhodophyta fyziologie MeSH
- světlosběrné proteinové komplexy chemie MeSH
- xanthofyly MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The effects of combining naturally evolved photosynthetic pigment-protein complexes with inorganic functional materials, especially plasmonically active metallic nanostructures, have been a widely studied topic in the last few decades. Besides other applications, it seems to be reasonable using such hybrid systems for designing future biomimetic solar cells. In this paper, we describe selected results that point out to various aspects of the interactions between photosynthetic complexes and plasmonic excitations in Silver Island Films (SIFs). In addition to simple light-harvesting complexes, like peridinin-chlorophyll-protein (PCP) or the Fenna-Matthews-Olson (FMO) complex, we also discuss the properties of large, photosynthetic reaction centers (RCs) and Photosystem I (PSI)-both prokaryotic PSI core complexes and eukaryotic PSI supercomplexes with attached antenna clusters (PSI-LHCI)-deposited on SIF substrates.
- MeSH
- chlorofyl a metabolismus MeSH
- fluorescenční spektrometrie metody MeSH
- formaldehyd chemie MeSH
- fotosyntéza * MeSH
- fotosystém I (proteinový komplex) metabolismus MeSH
- glukosa chemie MeSH
- karotenoidy metabolismus MeSH
- nanostruktury chemie ultrastruktura MeSH
- stříbro chemie MeSH
- světlosběrné proteinové komplexy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Kostní dřeň (BM) je jedním ze zdrojů hematopoetických kmenových buněk pro účely jejich alogenní transplantace. V retrospektivní studii jsme analyzovali odběry kostní dřeně 216 zdravých dárců za desetileté období 2007–2017. Dárcům byl vzhledem k jejich vyšší tělesné hmotnosti odebírán větší objem dřeně oproti dárkyním (1300 ml vs. 1100 ml), což vedlo k zisku většího množství jaderných buněk (156 vs. 124 x 106 TNC, p = ns). Získaný výtěžek závisel na objemu dřeně (p < 0,0001) a hmotnosti dárce (p = 0,01). Suboptimální transplantát s obsahem ≤ 2,0 x 108 TNC/kg příjemce byl odebrán v 6 % případů, vždy byl přítomen velký hmotnostní rozdíl mezi dárcem a příjemcem (medián 20 kg). Všem dárcům byla připravena k odběru BM jedna jednotka autologní krve. Vstupní hladina hemoglobinu dárců (Hb; 153 g/l u mužů, 135 g/l u žen) se snížila odběrem autotransfuze (AT) o cca 8 g/l a odběrem kostní dřeně o dalších cca 23 g/l. AT byla podána celkem u 70 % dárců, 30 % přípravků zůstalo nevyužito. Vyhodnocení rizika dosažení substitučních hodnot hemoglobinu (< 115 g/l u mužů, < 105 g/l u žen) ukázalo, že dárci s hladinou nad 145 g/l před odběrem a hmotností nad 75 kg mají minimální riziko potřeby substituce (cca 10 %). Výskyt komplikací v souvislosti s odběrem byl nízký (5 %) a žádná z nich nebyla klasifikována jako závažná. Analýza ukázala, že parametry dárce (hmotnost, hladina Hb) a příjemce (hmotnost) určují množství odebraných nukleárních buněk a také potřebu zajištění odběru AT. Vzhledem k tomu, že se mění postoj k využití AT při odběrech kostní dřeně, je na místě diskuze o benefitu a rizicích vyplývajících z odběrů autologní krve u dárců kostní dřeně.
Bone marrow (BM) is one of the sources of hematopoietic stem cells used for allogeneic transplantation. In this retrospective study, we analysed bone marrow harvests in 216 healthy donors over a ten-year period (2007–2017). Larger volumes of bone marrow were obtained from male compared to female donors (1300 ml vs. 1100 ml) due to their higher body weight, resulting in a higher number of nucleated cells (156 vs. 124 x 106 TNC, ns). The total yield was dependent on the volume of marrow (p < 0.0001) and donor weight (p = 0.01). Suboptimal grafts containing ≤ 2.0 x 108 TNC/kg (recipient) were collected in 6 % of cases, always with significant differences of weight between donor and recipient (median 20 kg). All donors underwent preoperative autologous blood donation (PAD). The initial haemoglobin level of 153 g/L (male donors) and 135 g/L (female donors) decreased by about 8 g/L after preoperative blood donation and by 23 g/L after bone marrow harvest. Auto-transfusion was administered to 70 % of donors, 30 % of the units remained unused. Evaluation of the risk of reaching transfusion threshold (<115 g/L males, < 105 g/L females) revealed that donors with initial haemoglobin level above 145 g/L and those weighing more than 75 kg have a minimal risk of requiring blood substitution (about 10 %). The incidence of adverse events associated with bone marrow harvests was low (5 %) and none of these were classified as serious. The analysis proved that the amount of nucleated cells harvested and substitution requirements are determined by donor parameters (weight, haemoglobin level) and recipient parameters (weight). Given the changing policy to auto-transfusion during bone marrow collection, the issue of balancing the benefits and risks of administering preoperative autologous transfusion should be addressed.
