67 (4588 0 Da), Bg 34 22 (4684 1 Da) On the other hand U-AITX-Bg

67 (4588.0 Da), Bg 34.22 (4684.1 Da). On the other hand U-AITX-Bg1a was not completely sequenced at the N-terminus; nonetheless the multiple sequence alignment (Fig. 4A) suggested

that the missing fragment is GT. Accordingly, the molecular mass of U-AITX-Bg1a should be 4593.3 Da which is in good agreement with the molecular mass of Bg 30.66b (4592.5 Da). For more clarity, refer to Fig. 2 and Fig. 3 to observe the peaks from RPC18 chromatography corresponding to the mentioned peptides. We should also stress that on sequence similarity search procedure, a translated nucleotide sequence from Anthopleura elegantissima encoding a putative neurotoxin (GenBank ID: gi|193259782) similar see more to these U-AITX-Bg1a–e peptides was identified [68]. We named it as U-AITX-Ael1a, following AZD2281 supplier the nomenclature

proposed by King et al. [44]. Even though its initial Met amino acid in the precursor is not determined, we may assume that its full CDS is as shown in Fig. 4B, based on the similarity in the alignment with the U-AITX-Bg1a–e peptides here reported. Interestingly, the precursors of U-AITX-Ael1a, U-AITX-Bg1b–d are closely related and present the KR cleavage site, as usual for most of the sea anemone neurotoxins. On the other hand, U-AITX-Bg1e precursor is more variable, being nine amino acids longer than the others and presenting the RR cleavage site. This is the first report of full CDS and precursors for this family of sea anemone toxins, and curiously, species from different genera (Bunodosoma vs. Anthopleura) present similar precursors, an unusual characteristic of sea anemone genes [58], [59] and [60]. On the contrary, the similarity search against the EST database of A. viridis (39,939 ESTs) provided no match to these toxins, revealing that such a category of peptides is not expressed in that species, in agreement to Kozlov and Grishin [45]. Molecular models of U-AITX-Bg1

(a–e), U-AITX-Ael1a and BcIV obtained by the I-Tasser server are represented in Fig. 5. The C-score for each model, as predicted by I-TASSER server were 0.861, 0.814, 0.769, 0.882, 0.570, Terminal deoxynucleotidyl transferase 0.953 and 0.395 (typically in the range from −5 to 2, higher values signifies a model with a high confidence), respectively. Also, their QMEAN scores and other parameters showed adequate values (data not shown), confirming a good agreement of structures based on APETx1 template and validating our models. Similarly to APETx1 [15] and APETx2 [16], the new APETx-like peptides U-AITX-Bg1 (a, b, d, and e) are composed of a compact core comprising four-stranded β sheets, from which the loop (16–27) and the N- and C-termini emerge. The β sheets sequence obeys (with slight differences) the APETx pattern: residues 3–6 (strand I), 9–14 (strand II), 28–32 (strand III) and 35–39 (strand IV), are connected by a type II β-turn (between strands I and II), a loop (between strands II and III) and a type I β-turn (between strands III and IV).

8–5 1 mg g− 1) [1], [23] and [24] The NIR models of protein
<

8–5.1 mg g− 1) [1], [23] and [24]. The NIR models of protein

and oil have been seen in soybean (Glycine max [L.] Merr.) (153 intact beans), soybean in Brazil (100 powder samples), field pea (Pisum arvense L.) and chickpea (Cicer arietinum L.) (165 and 151 in powder and intact seeds) were to improve seed quality in breeding program [25], [26] and [27]. In this study, a total of 244 genotypes of faba bean were evaluated with NIR models to determine content range of the seed constituents which is a far greater number than previous study [28]. The model for intact seed of faba bean was less precise than powder model possibly due to wide differences in particle size. The seed models click here could be optimized through principal component analysis (PCA). Several studies indicated that physical characteristics of seed samples, such as particle size, water

content and interaction between constituents significantly, influenced near infrared absorption and led to variation in the NIR results [29] and [30]. For field pea and chickpea, the calibration accuracy for the chemical constituents of the ground powder was also generally better BMS-354825 nmr than those for the intact seed samples [27] and [31]. Zong et al. [32] and [33] divided the varieties of faba bean germplasm into spring and winter types according to their natural seeding time and discussed their regional distribution. Based on the current research, a two-step cluster analysis determined the relationship between the contents of the seed constituents and regional differences accounted for differences in the seed characteristics of the faba bean samples. The majority

of faba bean varieties in the same producing area would be clustered into one group and the minority might be kicked out because of their special genotypes or growing conditions [1]. Additionally, the clustering results were in accordance with those of cluster research on faba bean using ISSR (Inter-simple Sequence Repeat) markers reported by Wang et al. [34]. In current study, influences of STK38 longitude, latitude, and elevation were observed on the nutrients content in faba bean. Nevertheless, latitude and elevation had a greater influence on these traits than longitude. Compared with faba bean, the influence of latitude on protein (negative, P < 0.01) and oil (positive, P < 0.05) in soybean was different [35]. In Poland, the highest crude protein yields were obtained on an altitude of 300 m and the lowest at 700 m [36]. Over a range of altitudes from 0 to 2256 m in Guatemala, the content of protein, starch, tannin and catechin were not affected [37]. Higher altitude is often associated with lower temperature and higher UV absorbance. The starch content of faba bean plants was significantly increased at lower temperature and higher UV exposure [38]. High level of UV irradiation will enhance the damage caused lipid peroxidation.

45 μm enclosed syringe filter unit and aliquots transferred to co

45 μm enclosed syringe filter unit and aliquots transferred to colourimetric reagents or subject to appropriate acid preservation. For on-site separation of As(III) species about ∼50 mL of 0.45 μm-filtered water was passed through solid arsenic-speciation cartridges

(Metalsoft) and preserved with concentrated HCl. The cartridge contains highly selective aluminosilicate that adsorbs As(V) and allows only As(III) to pass through the column (Le et al., 2000). For cations and trace metals, 50 mL of filtrate was preserved with 0.3 mL of concentrated HNO3−. For anions, the filtrate was pre-treated with 2 g per 50 mL of cation exchange resin [BioRad AG50W-XB (142–1421)] to prevent metal precipitation and subsequent scavenging of anions. All the water samples were protected

from sunlight and stored at 4 °C until further selleck chemicals analysis. Spectrophotometric analysis was performed on the same day of sample collection for dissolved Fe2+ and total Fe (FeTot) by the 1,10 Phenanthroline method (APHA, 2005); sulfide by the methylene blue method (Cline, 1969); alkalinity by the bromophenol blue method (Sarazin et al., 1999); phosphate by the ammonium molybdate method (Murphy and Riley, 1958); and ammonia by the salicylate method (Chemetrics® vacuvials kits). Additional UV–visible spectra were collected Ku-0059436 chemical structure on a filtered aliquot of each sample using an ocean optics portable spectrophotometer equipped with a 10 mm path length quartz cell (Dahlen et al., 2000). Arsenic was analyzed by Hydride Generation Atomic Absorption Spectrophotometry (HG-AAS; AA280FS, VARIAN Australia Pyt Ltd, Australia) (McCleskey et al., 2004) with a detection limit of 3.4 nM and a precision within 5%. Individual samples were analyzed in quadruplicate and data presented are means. Major cations, anions and trace elements were analyzed at the Environmental Analysis Laboratory (EAL), Southern Cross University (SCU). Cations (Na, K, Ca, Mg), trace elements (arsenic, Methocarbamol manganese, boron, molybdenum, vanadium, silver, mercury, silicon, iron, lead, chromium, cobalt, zinc, nickel, copper, barium, cadmium, aluminum and selenium) and anions (chloride, sulfur, phosphorus

and bromide) were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) (Perkin-Elmer ELAN-DRCe). For the purposes of this study, sulfur was assumed to be primarily SO42−, as S(-II) was below detection limits. Nitrate, nitrite and fluoride were analyzed by flow injection analysis (FIA) (LACHAT QuikChem 8000). Saturation indices (SI) were calculated using PHREEQC-2 for Windows V 2.15.06 (Parkhurst and Appelo, 1999) with stability constants derived from the Minteq database. Tubewell geochemical data are summarized in Table 1 and presented in relation to the depth of tubewell in Fig. 2. The groundwater is circum-neutral with pH (6.7–7.5) and the redox potential (pE) between 0.9 and 4.1 indicating the groundwaters are predominately moderately reducing and suboxic.

Wykazano, że w peroksysomach zachodzi ponad 50 reakcji biochemicz

Wykazano, że w peroksysomach zachodzi ponad 50 reakcji biochemicznych [4]. Obecnie zidentyfikowanych jest 87 białek peroksysomalnych uczestniczących w różnych rodzajach procesów biochemicznych, obejmujących zarówno syntezę, jak i katabolizm różnorodnych cząsteczek. Peroksysomy są między innymi miejscem biosyntezy fosfolipidów (plasmalogen), biosyntezy cholesterolu i dolicholu, β- i α-oksydacji kwasów tłuszczowych nasyconych, nienasyconych, 2-hydroksy- i 2-metylo- podstawionych kwasów, katabolizmu D-aminokwasów,

poliamin, metabolizmu transaminaz i puryn (tab. 1) [5]. Lista przemian biochemicznych związanych z peroksysomami wskazuje, że spełniają one rolę jako ważne, wielofunkcyjne, elementy Dapagliflozin ic50 struktur biochemicznych organizmu. Najważniejsze funkcje to uczestnictwo w detoksyfikacji nadtlenku wodoru i metabolizmie kwasów tłuszczowych. Ponad połowa białek (62%) zidentyfikowanych w strukturze peroksysomu jest związana z metabolizmem Selleckchem Anti-infection Compound Library lipidów, z tego 63% z procesem oksydacji. W tym dla β-oksydacji nasyconych kwasów o prostych łańcuchach węglowych zidentyfikowano 7 białek,

dla aktywacji długo- i bardzo długołańcuchowych kwasów tłuszczowych – 9, zaś w regulacji acyl-CoA/CoA – 11. Procesy utleniania kwasów tłuszczowych stanowią jedne z głównych szlaków metabolicznych przebiegających w tych organellach [5]. Błędy na szlakach przemian prowadzą do chorób manifestujących się ciężkimi objawami klinicznymi. Ze względu na to, że znaczna część reakcji jest związana właśnie z metabolizmem Roflumilast lipidów, związków niezbędnych w procesie tworzenia i funkcjonowania układu nerwowego, większości chorób peroksysomalnych towarzyszą objawy wynikające głównie z uszkodzenia OUN i CNS. Nieprawidłowości struktury i funkcji aparatu peroksysomalnego dotyczące biogenezy czy też funkcji/aktywności enzymów peroksysomalnych stanowią grupę wrodzonych błędów metabolicznych (inborn

errors of metabolizm) określanych jako choroby peroksysomalne [2]. Pierwsze opisy kliniczne chorób peroksysomalnych opublikowano w latach 20 i 60 XX wieku [6, 7]. W 1973 r. Goldfisher, w badaniach morfologicznych wykazał brak peroksysomów w hepatocytach i komórkach kanalików nerkowych u niemowląt z zespołem mózgowo-wątrobowo-nerkowym, zespołem Zellwegera. Spostrzeżenie to dało początek klasyfikacji nowej grupy chorób metabolicznych i umożliwiło właściwy kierunek badań [8]. Podłoże patogenetyczne chorób peroksysomalnych dzieli się zasadniczo na trzy grupy: choroby związane z (I) zaburzeniem biogenezy peroksysomów (peroxisomal biogenesis disorders, PBD), z (II) defektem pojedynczego enzymu lub białka oraz (III) choroby ze współistniejącym defektem peroksysomalnym ( tab. 2) [9]. Częstość występowania chorób peroksysomalnych jest zróżnicowana od bardzo rzadko występujących, jak np.

Preventing cytoplasmic relocalisation of Tfe3 blocks the loss of

Preventing cytoplasmic relocalisation of Tfe3 blocks the loss of ES cell pluripotency [ 35]. Interestingly, Wnts have recently been demonstrated to sustain ES cells in culture BMN 673 manufacturer when provided alongside LIF [36••]. Although this

has been proposed to occur by blockade of the ES to EpiSC transition, the mechanisms involved are not fully resolved [37]. Gene repression by TCF3 appears to play a part and has been proposed to explain how GSK3β inhibition can promote ES cell self-renewal [38 and 39]. Interestingly, the Nanog target gene Esrrb is amongst the most functionally relevant targets of GSK3β inhibition [40•]. Recently, E-cadherin, which is physically linked to Wnt signalling Selleck Neratinib via β-catenin, has been demonstrated to cooperate with LIFR/gp130 for LIF signalling [41], which could contribute

to the Wnt mediated effect. Relative to the in vitro generation of EpiSC, reprogramming by enforced expression can provide complementary information on the role of TFs in promoting acquisition of pluripotency. Nanog is not in the original reprogramming factor cocktail [ 42]. However, Nanog is expressed late during reprogramming [ 43, 44 and 45•] and is required to complete reprogramming [ 6]. Nanog−/− somatic cells can be reprogrammed to a state in which they acquire the morphology and growth factor dependence of ES cells [ 6]. However, as they neither activate endogenous pluripotency TF gene transcription, nor silence the reprogramming factor transgenes they are not fully reprogrammed [ 6]. This is interesting in light of recent data suggesting that pre-iPS cells may have high Oct4 transgene expression, which is incompatible with self-renewal of ES/iPS cells [ 46• and 47]. Restoring Nanog expression to partially reprogrammed lines facilitates the transition to a fully reprogrammed state [ 6]. This raises Tacrolimus (FK506) the intriguing possibility that Nanog plays a critical role in imposing the transcriptional and epigenetic state required to silence transgene expression. Recent evidence provides

some insight into the mechanisms by which Nanog may achieve reprogramming. Forced expression of the direct Nanog target gene Esrrb, in Nanog−/− pre-iPS cells triggers complete reprogramming when combined with 5’Azacytidine treatment [ 33••]. Furthermore, Nanog interacts with Tet1 ([ 48••] and our unpublished information) and induces Tet2 expression ([ 33•• and 48••] and Figure 2). Concomitant elevation of Tet1 and Nanog in Nanog−/− pre-iPSCs cooperatively enhances iPS cell generation [ 48••]. The overlap in chromatin binding between Tet1 and Nanog suggests that Nanog may bring Tet1 to the methylated regulatory regions of key pluripotency genes, thereby triggering hydroxymethylation, potential subsequent demethylation and activation of the PGRN.

As shown in Fig  6C and D, there was an increase in the oxidative

As shown in Fig. 6C and D, there was an increase in the oxidative damage score after incubation with Fpg and Endo III, indicating the presence of oxidized purines and pyrimidines. As the levels of ordinary and oxidatively generated DNA adducts were similar (mainly between 6 and 12 h), the majority of the DNA damage observed in the kidneys was likely due to oxidative insult (Fig. 6B–D). Since the administration of antilonomic serum (ALS) is the only specific

treatment actually available for L. obliqua envenomation, we decided to test its efficacy in neutralizing biochemical and coagulation abnormalities using our experimental model. For this purpose, ALS was intravenously administered at 2 or 6 h post-LOBE injection (1 mg/kg, s.c.). After 24 h of envenomation, different biochemical Fluorouracil nmr markers and coagulation parameters were determined ( Table 3). Generally, treatment with ALS is able to neutralize LOBE-induced biochemical alterations only if administered within the first 2 h of envenomation.

For example, animals treated with ALS at 2 h had a decrease of 3.6- and 2.5-fold in the levels of serum creatinine and urea, respectively, when compared with the group treated 6 h after LOBE injection. In addition, both the creatinine and urea levels of the envenomed animals that had been treated at 2 h with ALS were not significantly different from the values observed Duvelisib purchase in non-envenomed rats that had been treated with PBS or ALS, indicating Morin Hydrate that these levels had returned

to control values. Similar results were obtained for other parameters, such as CK, CK-MB, AST and ALT, which became normalized only in envenomed rats that had received ALS within the first 2 h. Likewise, plasma hemoglobin levels were also decreased in envenomed rats when ALS was injected at 2 h. However, this reduction was not statistically significant in comparison to envenomed animals that had been treated with PBS instead of ALS. Thus, ALS was not able to completely reverse intravascular hemolysis, even if given early after envenomation. As expected, envenomed animals that were treated with PBS developed consumptive coagulopathy, with lower levels of fibrinogen and prolonged activated partial thromboplastin time (Table 3). In this case, the treatment with ALS both at 2 or 6 h after venom injection normalized the coagulation parameters. The macroscopic and histological signs of hemorrhage were also absent in the envenomed groups that had received ALS injections at 2 or 6 h (results not shown). In the present study, we used an experimental model in rats to investigate the acute physiopathological effects of L. obliqua venom. This model allowed for the broad characterization of venom-induced tissue damage, including biochemical, hematological, histopathological, myotoxic, cardiotoxic and genotoxic alterations.

Porém, em pacientes com disfunção cognitiva leve, a gênese das al

Porém, em pacientes com disfunção cognitiva leve, a gênese das alterações na cognição ainda não está bem estabelecida21. Muitos testes neuropsicológicos têm sido projetados para a detecção de alterações na cognição27, mas podem não ser aplicáveis a estes pacientes. É importante a realização de estudos sobre testes neuropsicológicos

adequados para detectar sutis alterações cognitivas em hepatopatas e isto pode impulsionar o desenvolvimento de mais estudos sobre este problema através da aplicação de instrumentos de avaliação psicométrica uniformes. Conclui-se que a prevalência de encefalopatia clinicamente evidente foi 43,1%, enquanto 53,3% dos pacientes apresentaram déficit cognitivo, Docetaxel mouse atribuindo-se, portanto, uma prevalência estimada de «encefalopatia hepática mínima» a 10,2% da amostra, que não teriam sido detectados apenas com a aplicação dos critérios de Parsons-Smith. Contudo, reconhece-se AZD2281 mouse a limitação representada por esta avaliação, cuja aplicação pode ter causado uma subestimação da presença

de alterações cognitivas nos pacientes. As 2 avaliações (encefalopatia clínica pelos critérios de Parsons-Smith e avaliação pelo MEEM) não se correlacionaram com sinais clínicos de insuficiência hepática crônica, porém, se associaram com os escores da classificação de Child-Turcotte-Pugh, indicando que aqueles instrumentos de avaliação apresentaram acuidade satisfatória. Contudo, não se trata de um teste suficientemente sensível para medir alterações psicológicas e cognitivas em encefalopatia clínica e precisa ser submetido a outros estudos para avaliação de seu desempenho psicométrico em pacientes com encefalopatia subclínica. Ainda na discussão, poder-se-ia argumentar que o pequeno acréscimo, de 10%, conseguido pelos testes psicológicos na detecção de perturbação cerebral, pode ser consequência de se estudarem doentes internados, na sua maioria com encefalopatia clínica, e que os mesmos testes realizados em doentes de ambulatório, com doença hepática menos grave, poderá ter maior utilidade, como this website referido

por diversos outros autores que estudaram doentes de consulta, alguns com diagnóstico histológico e poucas alterações bioquímicas. Portanto, é importante a realização de estudos posteriores sobre testes neuropsicológicos adequados para detectar sutis alterações cognitivas em hepatopatas. Os autores declaram que os procedimentos seguidos estavam de acordo com os regulamentos estabelecidos pelos responsáveis da Comissão de Investigação Clínica e Ética e de acordo com os da Associação Médica Mundial e da Declaração de Helsinki. Os autores declaram ter seguido os protocolos de seu centro de trabalho acerca da publicação dos dados de pacientes e que todos os pacientes incluídos no estudo receberam informações suficientes e deram o seu consentimento informado por escrito para participar nesse estudo.

While recent years have brought a surge of attention to this area

While recent years have brought a surge of attention to this area of study, we believe this is just the beginning of a rich scientific enterprise. What are the factors that influence integration (Box 1)? How do neural representations simultaneously support the maintenance of episodic

detail and generalization across experiences? How do memory integration and behavioral flexibility change across the lifespan [51]? Everolimus in vitro These are merely examples of the many important questions that remain the subject of future investigation. Nothing declared. Papers of particular interest, published within the period of review, have been highlighted as: • of special interest This work was supported by the National Institute of Mental Health of the National Institutes of Health (R01 MH100121 to A.R.P.); by the National Science Foundation CAREER award (1056019 to A.R.P.); and by the Department of Defense (DoD) through the National Defense Science

& Engineering Graduate Fellowship (NDSEG) Program (to M.L.S.). “
“Current Opinion in Behavioral Sciences Tanespimycin research buy 2015, 1:9–16 This review comes from a themed issue on Cognitive neuroscience Edited by Cindy Lustig and Howard Eichenbaum http://dx.doi.org/10.1016/j.cobeha.2014.07.004 2352-1546/© 2014 Elsevier Ltd. All rights reserved. Interference control, which is the ability to protect ongoing cognitive processing from internal or environmental distraction, has long been a subject of interest in cognitive psychology. The ability to achieve interference control is strongly correlated with the performance of higher-order cognitive functions such as language comprehension, problem-solving, and fluid intelligence. Human

cognition studies have focused on inhibition-related functions 1, 2 and 3, and dual-task paradigms Montelukast Sodium have been used to investigate the mechanisms that underlie interference control. The general principle of the dual-task paradigm is for subjects to perform two relatively complex tasks simultaneously, each of which includes a distinct goal and stimulus-response association. Despite the remarkable flexibility of cognitive abilities, human subjects often exhibit decreased performance in either or both component tasks of the dual-task paradigm, since information processing for one task interferes with the other [4•]. The addition of a more cognitively demanding secondary task can strongly disrupt performance of the primary task. Since heavy cognitive demands on the information processing system are thought to produce dual-task interference, either a control mechanism to coordinate multiple processing streams, such as the central executive in working memory model 5 and 6•, or a control mechanism to flexibly allocate cognitive resource for each task 7 and 8, is required in addition to the control process for each component task. Recent behavioral studies have indicated that humans and animals exhibit a similar dual-task interference effect.

Strong archeological evidence suggests that the islands within th

Strong archeological evidence suggests that the islands within the northern

Lagoon have been inhabited since Roman times and up to the Medieval Age. Examples of wooden waterside structures were found dating back between the first century BC and the second century AD (Canal, 1998, Canal, 2013 and Fozzati, 2013). As explained in Housley et al. (2004), due to the need for dry land suitable for building, salt marshes were enclosed and infilled to support small islands on which early settlements were built. Sites that go back to Roman imperial times are now well documented in the northern part of the lagoon. In the city of Venice itself, however, the first archeological evidence found PD-0332991 ic50 so far dates back to the 5th century AD. Only later, in the 8th to 9th century AD, did Venice start to take the character of a city (Ammerman, 2003). By the end of the 13th century, Venice was a prosperous city with a population of about 100,000 inhabitants (Housley et al., 2004). At the beginning of the 12th century, sediment delivered by the system of rivers threatened to fill the lagoon (Gatto and Carbognin, 1981). In the short term, the infilling of sediment affected the navigation and harbor activity of Venice, while in the long term,

it opened up the city to military attack by land. This situation motivated the Venetians to divert the rivers away from the lagoon, so that the sediment load of the rivers would discharge directly into the Sitaxentan Adriatic Sea. This human intervention was carried out over the next few centuries so that all the main rivers see more flowing into the lagoon were diverted by the 19th century (Favero, 1985 and Bondesan and Furlanetto, 2012). If the Venetians had not

intervened, the fate of the Venice Lagoon could have been the same as that of a lagoon in the central part of the Gulf of Lions in the south of France. This lagoon was completely filled between the 12th and 13th century (Sabatier et al., 2010). In the 19th century, significant modifications included a reduction of the number of inlets from eight to three. The depth of the remaining inlets also increased from ∼5 m to ∼15 m, with a consequent increase in tidal flow and erosive processes (Gatto and Carbognin, 1981). In the last century, dredging of major navigation channels took place in the central part of the lagoon to enhance the harbor activity. The exploitation of underground water for the industrial area of Marghera (Fig. 1) contributed to a sinking of the bottom of the basin (Carbognin, 1992 and Brambati et al., 2003). Also, the lagoon surface decreased by more than 30 percent due to activities associated with land reclamation and fish-breeding. The morphological and ecological properties of the lagoon changed dramatically: salt marsh areas decreased by more than 50 percent (from 68 km2 in 1927 to 32 km2 in 2002) and some parts of the lagoon deepened (Carniello et al., 2009, Molinaroli et al., 2009 and Sarretta et al.

e photo-oxidative stress (Havaux & Kloppstech, 2001) Consistent

e. photo-oxidative stress (Havaux & Kloppstech, 2001). Consistently, Boo et al. (2011) found higher anthocyanin concentrations in lettuce when low temperature was applied Ipatasertib cost during the photoperiod than during the night. This interacting, enhancing effect of low temperature and radiation has also been reported for Arabidopsis thaliana, emphasizing that the combination of chilling and elevated PPFD is especially likely to induce photoinhibition and photo-oxidation in

higher plants ( Havaux & Kloppstech, 2001). This may explain why our results differ from those of Oh et al. (2009). Apart from the different time span investigated (1 day as compared to several weeks in our experiment), they subjected their lettuce plants to 4 °C concurrent with radiation. Furthermore, they reduced the temperature by 16 K to 4 °C while we only reduced by 8 K to 7 °C. The larger magnitude of change and the application of a lower temperature during the photoperiod may exert more severe stress on plants and thus lead to an enhanced response. The conditions we applied are more realistic regarding lettuce production in greenhouses than the drastic conditions applied by other studies. In agreement with Løvdal et al. (2010), we conclude that in our experiment, the cyanidin glycoside truly responded to changes in temperature alone Small molecule library ic50 while quercetin and luteolin glycosides did not. As mentioned

above (Section 3.3.1), an over-excited electron transport chain in chloroplasts mainly produces O2- by electron transfer. Although cyanidin and quercetin are both flavonoids and both comprise an ortho   3′,4′-dihydroxy moiety, cyanidin has a higher O2- scavenging activity than quercetin ( Chun, Kim, & Lee, 2003). Quercetin on the other hand, is very effective against singlet oxygen (1O2) which is formed by energy transfer from excited triplet-state chlorophyll ( Tournaire et al., 1993). The life time of triplet chlorophyll increases in

excess radiation ( Havaux & Kloppstech, 2001). This may explain the differential regulation of these two substances. This interpretation Tobramycin is corroborated by Gill and Tuteja (2010) who report that 1O2 is involved in the activation of early stress response genes that are different from those activated by O2-. Cool-cultivated small heads contained higher concentrations of caffeoylmalic acid than warm-cultivated ones (Fig. 4 and Table 1). However, regarding mature heads, this difference is not detectable any more (Fig. 4 and Table 1). This also supports the hypothesis that the applied conditions were more stressful to small heads than to larger ones (see Section 3.3.1). Neither with small heads nor with mature heads we detected significantly different concentrations of chicoric acid or chlorogenic acid between the temperature treatments (Fig. 4 and Table 1).