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Purpose: To investigate the prognostic value of survivin expression in pretreatment specimens from patients with anal cancer treated with concurrent 5-FU and mitomycin C-based chemoradiation (CRT). Material and methods: Immunohistochemical staining for survivin was performed in pretreatment biopsies of 62 patients with anal carcinoma. Survivin expression was correlated with clinical and histopathological characteristics as well as local failure free- (LFFS), distant metastases free- (DMFS), cancer specific- (CSS), and overall survival (OS). Results: Survivin staining intensity was weak in 10%, intermediate in 48% and intense in 42% of the patients. No association between survivin expression and clinicopathologic factors (tumor stage, age and HIV status) could be shown. In univariate analysis, the level of survivin staining was significantly correlated with DMFS (low survivin vs. high survivin: 94% vs. 74%, p=0.04). T-stage, N-stage and the tumor grading were significantly associated with OS and CSS and with DMFS and LFFS, respectively. In multivariate analysis, survivin was confirmed as independent prognostic parameter for DMFS (RR, 0.04; p=0.02) and for OS (RR, 0.27; p=0.04). Conclusion: Our results demonstrated that the level of pretreatment survivin is correlated with the clinical outcome in patients with anal carcinoma treated with concurrent CRT. Further studies are warranted to elucidate the complex role of survivin for the oncologic treatment and to exploit the protein as a therapeutic target in combined modality treatment of anal cancer.

Maximum photosynthetic capacity indicates that the Antarctic psychrophile Chlamydomonas raudensis H. Ettl UWO 241 is photosynthetically adapted to low temperature. Despite this finding, C. raudensis UWO 241 exhibited greater sensitivity to low-temperature photoinhibition of PSII than the mesophile Chlamydomonas reinhardtii P. A. Dang. However, in contrast with results for C. reinhardtii, the quantum requirement to induce 50% photoinhibition of PSII in C. raudensis UWO 241 (50 μmol photons) was comparable at either 8°C or 29°C. To our knowledge, this is the first report of a photoautotroph whose susceptibility to photoinhibition is temperature independent. In contrast, the capacity of the psychrophile to recover from photoinhibition of PSII was sensitive to temperature and inhibited at 29°C. The maximum rate of recovery from photoinhibition of the psychrophile at 8°C was comparable to the maximum rate of recovery of the mesophile at 29°C. We provide evidence that photoinhibition in C. raudensis UWO 241 is chronic rather than dynamic. The photoinhibition-induced decrease in the D1 content in C. raudensis recovered within 30 min at 8°C. Both the recovery of the D1 content as well as the initial fast phase of the recovery of Fv/Fm at 8°C were inhibited by lincomycin, a chloroplast protein synthesis inhibitor. We conclude that the susceptibility of C. raudensis UWO 241 to low-temperature photoinhibition reflects its adaptation to low growth irradiance, whereas the unusually rapid rate of recovery at low temperature exhibited by this psychrophile is due to a novel D1 repair cycle that is adapted to and is maximally operative at low temperature.

Using in vivo thermoluminescence, we examined the effects of growth irradiance and growth temperature on charge recombination events in photosystem IT reaction centres of the model green alga Chlamydomonas reinhardtii. We report that growth at increasing irradiance at either 29 or 15 degrees C resulted in comparable downward shifts in the temperature peak maxima (T-M) for S(2)Q(B)(-) charge pair recombination events, with minimal changes in S(2)Q(A)(-) recombination events. This indicates that such growth conditions decrease the activation energy required for S(2)QB(-) charge pair recombination events with no concomitant change in the activation energy for S(2)Q(A)(-) recombination events. This resulted in a decrease in the Delta T-M between S(2)Q(A)(-) and S(2)Q(B)(-) recombination events, which was reversible when shifting cells from low to high irradiance and back to low irradiance at 29 degrees C. We interpret these results to indicate that the redox potential of Q(B) was modulated independently of Q(A), which consequently narrowed the redox potential gap between Q(A) and Q(B) in photosystem II reaction centres. Since a decrease in the Delta T-M between S(2)Q(A)(-) and S(2)Q(B)(-) recombination events correlated with growth at increasing excitation pressure, we conclude that acclimation to growth under high excitation pressure narrows the redox potential gap between Q(A) and Q(B) in photosystem 11 reaction centres, enhancing the probability for reaction center quenching in C. reinhardtii. We discuss the molecular basis for the modulation of the redox state of Q(B), and suggest that the potential for reaction center quenching complements antenna quenching via the xanthophyll cycle in the photoprotection of C. reinhardtii from excess light., vR-Medicine, Internal

The effect of salt on the green alga Chlamydomonas raudensis Ettl (UWO241) was investigated. This physchrophilic alga was discovered in a permanently ice-covered lake in Antarctica in the beginning of the 90's and was then classified as Chlamydomonas subcaudata. A phylogenetic study by Pocock et al. (2004) revealed that this alga was in fact a C.raudensis species. The latter type species was first discovered in an alpine meadow in Czech republic and kept in the SAG culture collection as strain number 49.72.The aim of this study was to use the potential high sensitivity of the extremophile to understand the effect of salinity on photosynthesis of phytoplankton in the oceans, where microalgae play a key role in the carbon cycle on earth. It has to be determined if global warming, which is leading to the melting of the north ice cap and thus to the dilution of the North Atlantic ocean will have a negative impact on algal populations. This study lays the foundations for a larger study, which focuses on the compounds released by these green algae that could potentially counteract the greenhouse effect by increasing the albedo on earth. The study includes a comparison of C. raudensis UWO241 (psychrophilic strain) with C. raudensis SAG 49.72 (mesophilic strain) and the model organism C.reinhardtii, (mesophile). Also none of the latter two are known to be halotolerant. The growth kinetics of the three species has been investigated at different salinities ranging from 2 µM to 200 mM NaCl and between 24°C and 28°C for the mesophiles and from 2 µM to 850 mM at 8°C for the psychrophile. All algae were grown under 20 μmol quanta m-2 s-1 irradiance.Furthermore, chlorophyll a fluorescence was used to determine the stress level caused by the salt on the three species.

Phototaxis is movement induced by light; this phenomenon has been detected in several solitary green algae species and generally works as a balancing force against gravitaxis, creating a system for optimum vertical placing in relation to irradiance, (energy -demands/restrictions). We study phototaxis in the mesophilic green algae, Chlamydomonas reinhardtii and C. raudensis SAG 49.72, relative to phototaxis in the from Antarctica newly isolated obligate psychrophilic strain of C. Raudensis (UWO 241) (henceforth called UWO 241). This species has some unusual movement patterns (Pocock et. al 2004) which function is yet to be revealed. Phototactic movement has not earlier been monitored in the normal conditions (high salinity, low temperature) for this strain, though when exposed to extreme temperatures (25C) the organism displays movement patterns interpreted as positive phototaxis. (Pocock et. al 2004). This behaviour should lead to a more rapid destruction of the organism due to the damaging high light (high energy input). The study shows that the three species responds different to light stimuli, when temperature is set to 12 C (culturing temperature) or the respective optimum culture temperatures. Light response curves of phototaxis in the range of 0,5 to 3000 μmol quanta m-2 s-1, shows that C. raudensis SAG 49.72 produce positive phototaxis over the entire range while C. reinhardtii mainly shows negative reactions. UWO 241 seem to be unaffected by irradiance, thus showing only nondirectional behaviour. In a second set of experiments the cells were kept in Petri dishes and exposed to 3000 μmol quanta m-2 s-1 under 40 min, in a temperature range of 5C to 25C for each sample. The results show that C. reinhardtii was negatively phototactic at 5C, switching to positive phototaxis at 25C.

Surface water microalgae samples were collected during the ice-free period in a small subarctic wastewater stabilization pond system, complemented with chemical precipitation during the winter period (fellingsdam), and serving 310 persons. In the primary pond microalgae dominance alternated between the Cryptophyte Cryptomonas and green algae (Chlorophyta). In the second and third pond the general pattern was that Cryptomonas dominated during summer but was replaced by green algae in autumn and the following spring. Estimations of the microalgae part of the effluent COD and phosphorus showed that microalgae dominated these parameters for only 3-4 weeks of 12 evaluated. This does not support the reasoning behind the European Union directive of the use of filtered samples for effluent BOD, COD and SS from stabilization ponds, in contrast to other wastewater treatment methods. The reasons behind the EU's procedure for ponds are based on the assumption that stabilization ponds convert "sewage BOD" to "algal BOD". The results of this study suggest that further investigations of the microalgae function in subarctic wastewater stabilization ponds and fellingsdams should be conducted, before implementing the EC directive into Swedish law, or into similar laws in other countries with subarctic regions.

The sustainability of a microalgae wastewater treatment plant model (ALGA), assumed serving a small Swedish town with 10,000 inhabitants at latitude 60°N, was tested by comparing it to a conventional three-step treatment plant (WWTP), and a mechanical and chemical treatment plant (TP) complemented with a constructed wetland (TP + CW). Using two assessment methods—the socio-ecological principles method and emergy analysis—the ALGA model considered to have a better position for sustainable development, than the other two. In emergy terms the ALGA model had about half the resource use of the other two alternatives, and used most local free environmental resources, four times the TP + CW, and 100 times the WWTP. The violations against the second and third socio-ecological principles were considered equal for the three alternatives, the fourth was estimated to be in favor of the ALGA model, and the first principle was calculated to be in favor of the ALGA model with about eight times lower indicator value sum. Recirculation of nutrients back to society or production of economically viable products from the treatment by-products would strongly influence the sustainability. The ALGA model has a potential advantage due to interesting biochemical contents in the microalgae biomass, depending on what species will become dominating.

Weaning success of pond-cultured pikeperch and wild-caught perch (mean length 51 and 48 mm respectively) was evaluated using different weaning techniques and different formulated feeds. Juveniles that were fed formulated feed grew as well as or better than juveniles that were weaned successively using zooplankton or yolk. Four different formulated feeds (agglomerated marine larvae feed, marine larvae feed, trout feed and a semi-moist feed) were evaluated regarding specific growth rate (SGR), condition factor and a subjective stomach fullness estimate. The agglomerated marine larvae feed gave significantly better weaning performance than the other feeds regarding all parameters (SGR = 7.3% day(-1) and 3.4% day(-1) for pikeperch and perch respectively).

Photosynthetic acclimation to temperature and irradiance was studied in the filamentous, non-heterocystous cyanobacterium Plectonema boryanum UTEX 485. Growth rates of this cyanobacterium measured at ambient CO2 were primarily influenced by temperature with minimal effects of irradiance. Both growth temperature and irradiance affected linolenic (18:3) and linoleic acid (18:2) levels in the four major lipid classes in an independent but additive manner. In contrast, photosynthetic acclimation was not due to either growth temperature or irradiance per se, but rather, due to the interaction of these environmental factors. P. boryanum grown at low temperature and moderate irradiance mimicked cells grown at high light. Compared to cells grown at either 29°C/150 μmol m-2 s-1 (29/150) or 15/10, P. boryanum grown at either 15/150 or 29/750 exhibited: (1) reduced cellular levels of Chl a and phycobilisomes (PBS), and concomitantly higher content of an orange-red carotenoid, myxoxanthophyll; (2) higher light saturated rates (Pmax) when expressed on a Chl a basis but lower apparent quantum yields of oxygen evolution and (3) enhanced resistance to high light stress. P. boryanum grown at 15/150 regained normal blue-green pigmentation within 16 h after a temperature shift to 29°C at a constant irradiance of 150 μmol m-2 s-1. DBMIB and KCN but not DCMU and atrazine partially inhibited the change in myxoxanthophyll/Chl a ratio following the shift from 15 to 29°C. We conclude that P boryanum responds to either varying growth temperature or varying growth irradiance by adjusting the ability to absorb light through decreasing the cellular contents of Chl a and light-harvesting pigments and screening of excessive light by myxoxanthophyll predominantly localized in the cell wall/cell membrane to protect PSII from over-excitation. The possible role of redox sensing/signalling for photosynthetic acclimation of cyanobacteria to either temperature or irradiance is discussed.